ATP OIL & GAS CORPORATION as the Issuer, and THE BANK OF NEW YORK MELON TRUST COMPANY, N.A., as Trustee and Collateral Agent INDENTURE Dated as of April 23, 2010 11.875% Senior Second Lien Notes due 2015

Exhibit 4.1

ATP OIL & GAS CORPORATION

as the Issuer,

and

THE BANK OF NEW YORK MELON TRUST COMPANY, N.A.,

as Trustee and Collateral Agent

INDENTURE

Dated as of April 23, 2010

11.875% Senior Second Lien Notes due 2015

CROSS-REFERENCE TABLE


TIA Section		Indenture Section

310(a)(1)		7.10
(a)(2)		7.10
(a)(3)		N.A.
(a)(4)		N.A.
(a)(5)		7.8; 7.10
(b)		7.3; 7.8; 7.10; 11.2
(c)		N.A.
311(a)		7.11
(b)		7.11
(c)		N.A.
312(a)		2.5
(b)		11.3
(c)		11.3
313(a)		7.6
(b)(1)		N.A.
(b)(2)		7.6; 13.2
(c)		7.6; 11.2
(d)		7.6
314(a)		4.6; 4.8
(b)		N/A
(c)(1)		11.4
(c)(2)		11.4
(c)(3)		N.A.
(d)		N.A.
(e)		11.5
(f)		N.A.
315(a)		7.1(b)
(b)		7.5
(c)		7.1(a)
(d)		7.1(c)
(e)		6.11
316(a)(last sentence)		2.9
(a)(1)(A)		6.5
(a)(1)(B)		6.4
(a)(2)		N.A.
(b)		6.7
(c)		9.4
317(a)(1)		6.8
(a)(2)		6.9
(b)		2.4
318(a)		11.1
(b)		N.A.
(c)		11.1

N.A. means Not Applicable

NOTE: This Cross-Reference Table shall not, for any purpose, be deemed to be a part of the Indenture.

TABLE OF CONTENTS


		Page

	ARTICLE I.

	DEFINITIONS AND INCORPORATION BY REFERENCE

SECTION 1.1.	Definitions	1
SECTION 1.2.	Incorporation by Reference of TIA	55
SECTION 1.3.	Rules of Construction	55

	ARTICLE II.

	THE NOTES

SECTION 2.1.	Form and Dating	56
SECTION 2.2.	Execution and Authentication; Aggregate Principal Amount	57
SECTION 2.3.	Registrar and Paying Agent	58
SECTION 2.4.	Paying Agent To Hold Assets in Trust	58
SECTION 2.5.	Holder Lists	59
SECTION 2.6.	Transfer and Exchange	59
SECTION 2.7.	Replacement Notes	71
SECTION 2.8.	Outstanding Notes	71
SECTION 2.9.	Treasury Notes	72
SECTION 2.10.	Temporary Notes	72
SECTION 2.11.	Cancellation	72
SECTION 2.12.	Reserved	73
SECTION 2.13.	CUSIP Number	73
SECTION 2.14.	Deposit of Monies	73
SECTION 2.15.	Restrictive Legends	73
SECTION 2.16.	Designation	76

	ARTICLE III.

	REDEMPTION

SECTION 3.1.	Notices to Trustee	76
SECTION 3.2.	Selection of Notes To Be Redeemed	76
SECTION 3.3.	Optional Redemption	77
SECTION 3.4.	Notice of Redemption	77
SECTION 3.5.	Effect of Notice of Redemption	78
SECTION 3.6.	Deposit of Redemption Price	79
SECTION 3.7.	Notes Redeemed in Part	79

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	ARTICLE IV.

	COVENANTS

SECTION 4.1.	Payment of Notes	79
SECTION 4.2.	Maintenance of Office or Agency	80
SECTION 4.3.	Organizational Existence	80
SECTION 4.4.	Payment of Taxes and Other Claims	80
SECTION 4.5.	Maintenance of Properties and Insurance	80
SECTION 4.6.	Compliance Certificate; Notice of Default	81
SECTION 4.7.	Compliance with Laws	82
SECTION 4.8.	Reports to Holders	82
SECTION 4.9.	Waiver of Stay, Extension or Usury Laws	83
SECTION 4.10.	Limitation on Restricted Payments	83
SECTION 4.11.	Limitations on Affiliate Transactions	89
SECTION 4.12.	Limitation on Incurrence of Indebtedness and Preferred Stock	92
SECTION 4.13.	Limitation on Restrictions on Distributions from Restricted Subsidiaries	96
SECTION 4.14.	Reserved	100
SECTION 4.15.	Change of Control	100
SECTION 4.16.	Limitation on Sales of Assets and Subsidiary Stock	102
SECTION 4.17.	Reserved	106
SECTION 4.18.	Limitation on Liens	106
SECTION 4.19.	Limitation on Lines of Business	107
SECTION 4.20.	Additional Subsidiary Guarantees	107

	ARTICLE V.

	SUCCESSOR CORPORATION

SECTION 5.1.	Merger, Consolidation and Sale of All or Substantially All Assets	108

	ARTICLE VI.

	REMEDIES

SECTION 6.1.	Events of Default	110
SECTION 6.2.	Acceleration	112
SECTION 6.3.	Other Remedies	113
SECTION 6.4.	Waiver of Past Defaults	113
SECTION 6.5.	Control by Majority	114
SECTION 6.6.	Limitation on Suits	114

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		Page

SECTION 6.7.	Right of Holders To Receive Payment	115
SECTION 6.8.	Collection Suit by Trustee	115
SECTION 6.9.	Trustee May File Proofs of Claim	115
SECTION 6.10.	Priorities	116
SECTION 6.11.	Undertaking for Costs	116
SECTION 6.12.	Restoration of Rights and Remedies	116

	ARTICLE VII.

	TRUSTEE

SECTION 7.1.	Duties of Trustee	117
SECTION 7.2.	Rights of Trustee	118
SECTION 7.3.	Individual Rights of Trustee	119
SECTION 7.4.	Trustee’s Disclaimer	120
SECTION 7.5.	Notice of Default	120
SECTION 7.6.	Reports by Trustee to Holders	120
SECTION 7.7.	Compensation and Indemnity	120
SECTION 7.8.	Replacement of Trustee	121
SECTION 7.9.	Successor Trustee by Merger, Etc.	122
SECTION 7.10.	Eligibility; Disqualification	123
SECTION 7.11.	Preferential Collection of Claims Against the Issuer	123
SECTION 7.12.	Force Majeure	123
SECTION 7.13.	Defaults and Events of Default	123

	ARTICLE VIII.

	DISCHARGE OF INDENTURE; DEFEASANCE

SECTION 8.1.	Termination of Issuer’s Obligations	124
SECTION 8.2.	Application of Trust Money	126
SECTION 8.3.	Repayment to the Issuer	127
SECTION 8.4.	Reinstatement	127
SECTION 8.5.	Acknowledgment of Discharge by Trustee	128

	ARTICLE IX.

	MODIFICATION OF THE INDENTURE

SECTION 9.1.	Without Consent of Holders	128
SECTION 9.2.	With Consent of Holders	130
SECTION 9.3.	Compliance with Trust Indenture Act	131
SECTION 9.4.	Revocation and Effect of Consents	131
SECTION 9.5.	Notation on or Exchange of Notes	132

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		Page

SECTION 9.6.	Trustee To Sign Amendments, Etc.	132

	ARTICLE X.

	[RESERVED]

	ARTICLE XI.

	MISCELLANEOUS

SECTION 11.1.	TIA Controls	133
SECTION 11.2.	Notices	133
SECTION 11.3.	Communications by Holders with Other Holders	134
SECTION 11.4.	Certificate and Opinion as to Conditions Precedent	134
SECTION 11.5.	Statements Required in Certificate or Opinion	135
SECTION 11.6.	Rules by Trustee, Paying Agent, Registrar	135
SECTION 11.7.	Legal Holidays	135
SECTION 11.8.	Governing Law	135
SECTION 11.9.	No Adverse Interpretation of Other Agreements	136
SECTION 11.10.	No Personal Liability	136
SECTION 11.11.	Successors	136
SECTION 11.12.	Duplicate Originals	136
SECTION 11.13.	Severability	136
SECTION 11.14.	Independence of Covenants	136
SECTION 11.15.	Waiver of Jury Trial	137
SECTION 11.16.	U.S.A. Patriot Act	137

	ARTICLE XII.

	SUBSIDIARY GUARANTEE OF NOTES

SECTION 12.1.	Unconditional Subsidiary Guarantee	137
SECTION 12.2.	Limitations on Subsidiary Guarantees	139
SECTION 12.3.	Execution and Delivery of Subsidiary Guarantee Notation	139
SECTION 12.4.	Release of a Subsidiary Guarantor	139
SECTION 12.5.	Waiver of Subrogation	140
SECTION 12.6.	Immediate Payment	141
SECTION 12.7.	No Set-Off	141
SECTION 12.8.	Obligations Absolute	141
SECTION 12.9.	Obligations Continuing	141
SECTION 12.10.	Obligations Not Reduced	142
SECTION 12.11.	Obligations Reinstated	142
SECTION 12.12.	Obligations Not Affected	142

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		Page

SECTION 12.13.	Waiver	144
SECTION 12.14.	No Obligation To Take Action Against the Issuer	144
SECTION 12.15.	Dealing with the Issuer and Others	144
SECTION 12.16.	Default and Enforcement	145
SECTION 12.17.	Amendment, Etc.	145
SECTION 12.18.	Acknowledgment	145
SECTION 12.19.	Costs and Expenses	145
SECTION 12.20.	No Merger or Waiver; Cumulative Remedies	145
SECTION 12.21.	Survival of Obligations	146
SECTION 12.22.	Subsidiary Guarantee in Addition to Other Obligations	146
SECTION 12.23.	Severability	146
SECTION 12.24.	Successors and Assigns	146

	ARTICLE XIII.

	SECURITY

SECTION 13.1.	Collateral and Security Documents; Further Assurances;	147
SECTION 13.2.	Recordings and Opinions	148
SECTION 13.3.	Release of Collateral	149
SECTION 13.4.	Maintenance of Collateral	150
SECTION 13.5.	Information Regarding Collateral	151
SECTION 13.6.	Suits to Protect the Collateral	152
SECTION 13.7.	Authorization of Receipt of Funds by the Trustee Under the Security Documents	153
SECTION 13.8.	Purchase Protected	153
SECTION 13.9.	Powers Exercisable by Receiver or Trustee	153
SECTION 13.10.	Release upon Termination of the Issuer’s Obligations	154
SECTION 13.11.	Collateral Agent	154
SECTION 13.12.	Compensation and Indemnification	159
SECTION 13.13.	Security Documents; Intercreditor Agreement; Other Security Documents	159

	ARTICLE XIV.

	RANKING OF LIENS

SECTION 14.1.	Relative Rights	160


EXHIBITS

Exhibit A		Form of Note
Exhibit B		Form of Certificate of Transfer

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Exhibit C		Form of Certificate of Exchange
Exhibit D		Form of Subsidiary Guarantee Notation

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INDENTURE, dated as of April 23, 2010, among ATP Oil & Gas Corporation, a Texas corporation (the “Issuer”), and The Bank of New York Mellon Trust Company, N.A., as trustee (in such capacity, the “Trustee”) and as collateral agent (in such capacity, the “Collateral Agent”).

The Issuer has duly authorized the creation of an issue of 11.875% Senior Second Lien Notes due 2015 (the “Notes”) and, to provide therefor, the Issuer has duly authorized the execution and delivery of this Indenture. All things necessary to make the Notes, when duly issued and executed by the Issuer, and authenticated and delivered under this Indenture, the valid obligations of the Issuer, and to make this Indenture a valid and binding agreement of the Issuer, have been done.

Each party hereto agrees as follows for the benefit of the other party and for the equal and ratable benefit of the Holders of the Notes.

ARTICLE I.

DEFINITIONS AND INCORPORATION BY REFERENCE

SECTION 1.1. Definitions.

“144A Global Note” means a Global Note substantially in the form of Exhibit A hereto bearing the Global Note Legend and the Private Placement Legend and deposited with or on behalf of, and registered in the name of, the Depository or its nominee that will be issued in a denomination equal to the outstanding principal amount of the Notes sold in reliance on Rule 144A.

“Acquired Indebtedness” means Indebtedness (i) of a Person or any of its Subsidiaries existing at the time such Person becomes or is merged with and into a Restricted Subsidiary or (ii) assumed in connection with the acquisition of assets from such Person, in each case whether or not Incurred by such Person in connection with, or in anticipation or contemplation of, such Person becoming a Restricted Subsidiary or such acquisition. Acquired Indebtedness shall be deemed to have been Incurred, with respect to clause (i) of the preceding sentence, on the date such Person becomes or is merged with and into a Restricted Subsidiary and, with respect to clause (ii) of the preceding sentence, on the date of consummation of such acquisition of assets.

“Additional Assets” means:

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(1) any properties or assets (i) to be used or that will be useful by the Issuer or a Restricted Subsidiary in the Oil and Gas Business or (ii) that replace properties or assets that were the subject of an Asset Disposition;

(2) capital expenditures by the Issuer or a Restricted Subsidiary in the Oil and Gas Business;

(3) the Capital Stock of a Person that becomes a Restricted Subsidiary as a result of the acquisition of such Capital Stock by the Issuer or a Restricted Subsidiary; or

(4) Capital Stock constituting a minority interest in any Person that at such time is a Restricted Subsidiary;

provided, however, that, in the case of clauses (3) and (4), such Restricted Subsidiary is primarily engaged in the Oil and Gas Business.

“Additional Notes” means Notes, in addition to, and having identical terms (except for a date of original issuance different than the Issue Date) as, the $1,500,000,000 aggregate principal amount of Notes issued on the Issue Date, issued pursuant to Article II and in compliance with Section 4.12.

“Adjusted Consolidated Net Tangible Assets” of a Person means (without duplication), as of the date of determination, the remainder of:

(a) the sum of:

(i) discounted future net revenues from proved oil and gas reserves of such Person and its Restricted Subsidiaries calculated in accordance with SEC guidelines before any state or federal income taxes, as estimated by the Issuer in a reserve report prepared as of the end of the Issuer’s most recently completed fiscal year for which audited financial statements are available, as increased by, as of the date of determination, the estimated discounted future net revenues from

(A) estimated proved oil and gas reserves acquired since such year end, which reserves were not reflected in such year-end reserve report, and

(B) estimated oil and gas reserves attributable to extensions, discoveries and other additions and upward revisions of estimates of proved oil and gas reserves since such year end due to exploration, development or exploitation, production or other activities which would,

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in accordance with standard industry practice, cause such revisions, in the case of clauses (A) and (B) calculated in accordance with SEC guidelines (utilizing the prices utilized in such Person’s year-end reserve report),

and decreased by, as of the date of determination, the estimated discounted future net revenues from

(D) estimated oil and gas reserves attributable to downward revisions of estimates of proved oil and gas reserves since such year end due to changes in geological conditions or other factors which would, in accordance with standard industry practice, cause such revisions, in each case calculated on a pretax basis and substantially in accordance with SEC guidelines in the case of clauses (C) and (D) (utilizing the prices utilized in such Person’s year-end reserve report),

provided, however, that in the case of each of the determinations made pursuant to clauses (A) through (D), such increases and decreases shall be as estimated by the Issuer’s petroleum engineers;

(ii) the capitalized costs that are attributable to Oil and Gas Properties of such Person and its Restricted Subsidiaries to which no proved oil and gas reserves are attributable, based on such Person’s books and records as of a date no earlier than the date of such Person’s latest available annual or quarterly financial statements;

(iii) the Net Working Capital of such Person on a date no earlier than the date of such Person’s latest annual or quarterly financial statements; and

(iv) the greater of:

(A) the net book value of other tangible assets of such Person and its Restricted Subsidiaries, as of a date no earlier than the date of such Person’s latest annual or quarterly financial statement, and

(B) the appraised value, as estimated by independent appraisers, of other tangible assets of such Person and its Restricted Subsidiaries, as of a date no earlier than the date of such Person’s latest audited financial statements; provided, that, if no such appraisal has been

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performed the Issuer shall not be required to obtain such an appraisal and only clause (a)(iv)(A) of this definition shall apply;

minus

(b) the sum of:

(i) Minority Interests;

(ii) any net gas balancing liabilities of such Person and its Restricted Subsidiaries reflected in such Person’s latest annual or quarterly balance sheet (to the extent not deducted in calculating Net Working Capital of such Person in accordance with clause (a)(iii) above of this definition);

(iii) to the extent included in (a)(i) above, the discounted future net revenues, calculated in accordance with SEC guidelines (utilizing the prices utilized in such Person’s year end reserve report), attributable to reserves which are required to be delivered to third parties to fully satisfy the obligations of the Issuer and its Restricted Subsidiaries with respect to Volumetric Production Payments (determined, if applicable, using the schedules specified with respect thereto);

(iv) the discounted future net revenues, calculated in accordance with SEC guidelines, attributable to reserves subject to Dollar-Denominated Production Payments which, based on the estimates of production and price assumptions included in determining the discounted future net revenues specified in (a)(i) above, would be necessary to fully satisfy the payment obligations of such Person and its Subsidiaries with respect to Dollar-Denominated Production Payments (determined, if applicable, using the schedules specified with respect thereto); and

(v) the present value of any overriding royalty interests in the form of net profits interests which are recorded as liabilities on the Issuer’s most recent balance sheet included in its annual or quarterly financial statements.

If the Issuer changes its method of accounting from the successful efforts method of accounting to the full cost or a similar method, “Adjusted Consolidated Net Tangible Assets” will continue to be calculated as if the Issuer were still using the successful efforts method of accounting.

“Affiliate” of any specified Person means any other Person directly or indirectly controlling or controlled by or under direct or indirect common control with such specified Person. For the purposes of this definition, “control” when used with respect to any Per-

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son means the power to direct the management and policies of such Person, directly or indirectly, whether through the ownership of voting securities, by contract or otherwise; and the terms “controlling” and “controlled” have meanings correlative to the foregoing.

“Affiliate Transaction” has the meaning provided in Section 4.11.

“Agent” means any Registrar, Paying Agent or co-Registrar.

“Applicable Premium” means, with respect to any Note on any applicable Redemption Date, the greater of:

(1) 1.0% of the principal amount of such Note; and

(2) the excess, if any, of:

(a) the present value at such Redemption Date of (i) the Redemption Price of such Note at May 1, 2013 (such Redemption Price being set forth in the table appearing in Section 3.3) plus (ii) all required interest payments (excluding accrued and unpaid interest to, but not including, such Redemption Date) due on such Note through May 1, 2013, computed using a discount rate equal to the Treasury Rate as of such Redemption Date plus 50 basis points; over

(b) the principal amount of such Note.

“Applicable Procedures” means, with respect to any transfer or exchange of or for beneficial interests in any Global Note, the rules and procedures of the Depository, Euroclear and/or Clearstream that apply to such transfer or exchange.

“Asset Disposition” means any direct or indirect sale, lease (other than an operating lease entered into in the ordinary course of the Oil and Gas Business), transfer, issuance or other disposition, or a series of related sales, leases, transfers, issuances or dispositions that are part of a common plan, of (A) shares of Capital Stock of a Subsidiary (other than Preferred Stock of Restricted Subsidiaries issued in compliance with Section 4.12, and directors’ qualifying shares or shares required by applicable law to be held by a Person other than the Issuer or a Restricted Subsidiary), (B) all or substantially all the assets of any division or line of business of the Issuer or any Restricted Subsidiary (excluding any division or line of business the assets of which are owned by an Unrestricted Subsidiary) or (C) any other assets of the Issuer or any Restricted Subsidiary outside of the ordinary course of business of the Issuer or such Restricted Subsidiary (each referred to for the purposes of this definition as a “disposition”), in each case by the Issuer or any of its Restricted Subsidiaries, including any disposition by means of a merger, consolidation or similar transaction.

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Notwithstanding the preceding, the following items shall not be deemed to be Asset Dispositions:

(1) a disposition by a Restricted Subsidiary to the Issuer or by the Issuer or a Restricted Subsidiary to a Restricted Subsidiary;

(2) the sale of cash and Cash Equivalents in the ordinary course of business;

(3) a disposition of Hydrocarbons or mineral products inventory in the ordinary course of business;

(4) a disposition of damaged, unserviceable, obsolete or worn-out equipment or equipment that is no longer necessary for the proper conduct of the business of the Issuer and its Restricted Subsidiaries and that is disposed of in each case in the ordinary course of business;

(5) transactions in accordance with Section 5.1;

(6) an issuance of Capital Stock by a Restricted Subsidiary to the Issuer or to a Restricted Subsidiary;

(7) the making of a Permitted Investment or a Restricted Payment (or a disposition that would constitute a Restricted Payment but for the exclusions from the definition thereof) permitted in Section 4.10;

(8) an Asset Swap;

(9) dispositions of assets with a fair market value (as determined by the Issuer’s Board of Directors in good faith) of less than $20.0 million in the aggregate in any particular fiscal year;

(10) Permitted Liens;

(11) dispositions of receivables in connection with the compromise, settlement or collection thereof in the ordinary course of business or in bankruptcy or similar proceedings and exclusive of factoring or similar arrangements;

(12) the licensing or sublicensing of intellectual property (including, without limitation, the licensing of seismic data) or other general intangibles and licenses, leases or subleases of other property in the ordinary course of business which do not materially interfere with the business of the Issuer and its Restricted Subsidiaries;

(13) foreclosure on assets;

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(14) any Production Payments and Reserve Sales solely to the extent that any such Production Payments and Reserve Sales, other than incentive compensation programs on terms that are reasonably customary in the Oil and Gas Business for geologists, geophysicists and other providers of technical services to the Issuer or a Restricted Subsidiary, are created, Incurred, issued, assumed or Guaranteed in connection with the financing of, and within 60 days after the acquisition of, the property that is subject thereto;

(15) a disposition of oil and natural gas properties in connection with tax credit transactions complying with Section 29 or any successor or analogous provisions of the Code;

(16) surrender or waiver of contract rights, oil and gas leases, or the settlement, release or surrender of contract, tort or other claims of any kind;

(17) the abandonment, farm-out, lease or sublease of developed or undeveloped Oil and Gas Properties in the ordinary course of business;

(18) the sale or transfer (whether or not in the ordinary course of business) of any Oil and Gas Property or interest therein to which no proved reserves are attributable at the time of such sale or transfer;

(19) any overriding royalty interests in the form of net profits interests in Oil and Gas Properties granted to vendors in exchange for Oil and Gas Property development services related to such Oil and Gas Properties; and

(20) a designation of any Infrastructure Subsidiary as an Unrestricted Subsidiary in accordance with the requirements therefor set forth in the definition of “Unrestricted Subsidiary.”

“Asset Disposition Offer” has the meaning set forth in Section 4.16.

“Asset Disposition Offer Amount” has the meaning set forth in Section 4.16.

“Asset Disposition Offer Period” has the meaning set forth in Section 4.16.

“Asset Disposition Purchase Date” has the meaning set forth in Section 4.16.

“Asset Swap” means any substantially contemporaneous (and in any event occurring within 180 days of each other) purchase and sale or exchange of any oil or natural gas properties or assets or interest therein between the Issuer or any of its Restricted Subsidiaries and another Person; provided that any cash received must be applied in accordance with Section 4.16 as if the Asset Swap were an Asset Disposition.

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“Authenticating Agent” has the meaning provided in Section 2.2.

“Authentication Order” has the meaning provided in Section 2.2.

“Average Life” means, as of the date of determination, with respect to any Indebtedness or Preferred Stock, the quotient obtained by dividing (1) the sum of the products of the numbers of years from the date of determination to the dates of each successive scheduled principal payment of such Indebtedness or redemption or similar payment with respect to such Preferred Stock multiplied by the amount of such payment by (2) the sum of all such payments.

“Banking Obligations” means all obligations owing by the Issuer or any Subsidiary Guarantor to any Banking Services Provider in respect of any Banking Services (including, without limitation, indemnities, fees and interest thereon and all interest and fees that accrue on or after the commencement of any Insolvency or Liquidation Proceeding at the rate provided for in the respective documents governing the Banking Services, whether or not a claim for post-petition interest or fees is allowed or allowable in any such Insolvency or Liquidation Proceeding), now existing or hereafter incurred under, arising out of or in connection with such Banking Services, and the due performance and compliance by the Issuer or such Subsidiary Guarantor with the terms, conditions and agreements of such Banking Services.

“Banking Services” means each and any of the following bank services provided to the Issuer or any Subsidiary Guarantor by any Banking Services Provider: (a) commercial credit cards, (b) stored value cards and (c) treasury management services (including, without limitation, controlled disbursement, automated clearinghouse transactions, return items, overdrafts and interstate depository network services).

“Banking Services Provider” means any First-Lien Lender or any affiliate of a First-Lien Lender providing Banking Services to the Issuer or any Subsidiary Guarantor.

“Bankruptcy Law” means Title 11, U.S. Code or any similar Federal, state or foreign law for the relief of debtors.

“Beneficial Owner” has the meaning assigned to such term in Rule 13d-3 and Rule 13d-5 under the Exchange Act, except that in calculating the beneficial ownership of any particular “person” (as that term is used in Section 13(d)(3) of the Exchange Act), such “person” will be deemed to have beneficial ownership of all securities that such “person” has the right to acquire by conversion or exercise of other securities, whether such right is currently exercisable or is exercisable only after the passage of time. The terms “Beneficially Owns” and “Beneficially Owned” have a corresponding meaning.

“Board of Directors” means, as to any Person that is a corporation, the board of directors of such Person or any duly authorized committee thereof or as to any Person that is

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not a corporation, the board of managers or such other individual or group serving a similar function.

“Board Resolution” means, with respect to any Person, a copy of a resolution certified by the Secretary or an Assistant Secretary of such Person to have been duly adopted by the Board of Directors of such Person and to be in full force and effect on the date of such certification, and delivered to the Trustee.

“Business Day” means each day that is not a Saturday, Sunday or other day on which commercial banking institutions in New York, New York are authorized or required by law to close.

“Capital Stock” of any Person means any and all shares, units, interests, rights to purchase, warrants, options, participations or other equivalents of or interests in (however designated) equity of such Person, including any Preferred Stock, but excluding any debt securities convertible into such equity.

“Capitalized Lease Obligations” means an obligation that is required to be classified and accounted for as a capitalized lease for financial reporting purposes in accordance with GAAP, and the amount of Indebtedness represented by such obligation will be the capitalized amount of such obligation at the time any determination thereof is to be made as determined in accordance with GAAP, and the Stated Maturity thereof will be the date of the last payment of rent or any other amount due under such lease prior to the first date such lease may be terminated without penalty.

“Cash Equivalents” means:

(1) securities issued or directly and fully guaranteed or insured by the United States Government or any agency or instrumentality of the United States (provided that the full faith and credit of the United States is pledged in support thereof), having maturities of not more than one year from the date of acquisition;

(2) marketable general obligations issued by any state of the United States of America or any political subdivision of any such state or any public instrumentality thereof maturing within one year from the date of acquisition and, at the time of acquisition, having a credit rating of “A” (or the equivalent thereof) or better from either S&P or ▇▇▇▇▇’▇;

(3) certificates of deposit, time deposits, eurodollar time deposits, overnight bank deposits or bankers’ acceptances having maturities of not more than one year from the date of acquisition thereof issued by any commercial bank the short-term deposit of which is rated at the time of acquisition thereof at least “A2” or the

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equivalent thereof by S&P, or “P-2” or the equivalent thereof by ▇▇▇▇▇’▇, and having combined capital and surplus in excess of $250.0 million;

(4) repurchase obligations with a term of not more than thirty days for underlying securities of the types described in clauses (1), (2) and (3) entered into with any bank meeting the qualifications specified in clause (3) above;

(5) commercial paper rated at the time of acquisition thereof at least “A2” or the equivalent thereof by S&P or “P-2” or the equivalent thereof by ▇▇▇▇▇’▇, or carrying an equivalent rating by a nationally recognized rating agency, if both of the two named rating agencies cease publishing ratings of investments, and in any case maturing within one year after the date of acquisition thereof;

(6) interests in any investment company or money market fund which invests 95% or more of its assets in instruments of the type specified in clauses (1) through (5) above; and

(7) other short-term investments utilized by Foreign Subsidiaries in accordance with normal investment practices for cash management in investments of a type analogous to the foregoing.

“Cash-Pay Preferred” shall mean any Preferred Stock the terms of which (a) require the payment of cash dividends but otherwise do not contain any other provisions that would cause such Preferred Stock to constitute “Disqualified Stock,” (b) do not contain any significant restrictive or negative covenants, as determined in good faith by the Issuer and (c) otherwise are materially consistent with those customarily found in cash pay preferred stock offerings, as determined in good faith by the Issuer.

“Change of Control” means:

(1) any “person” or “group” of related persons (as such terms are used in Sections 13(d) and 14(d) of the Exchange Act) is or becomes the Beneficial Owner, directly or indirectly, of more than 50% of the total voting power of the Voting Stock of the Issuer (or its successor by merger, consolidation or purchase of all or substantially all of its assets) (for the purposes of this clause (1), such person or group shall be deemed to Beneficially Own any Voting Stock of the Issuer held by a parent entity, if such person or group Beneficially Owns, directly or indirectly, more than 50% of the total voting power of the Voting Stock of such parent entity);

(2) the first day on which a majority of the members of the Board of Directors of the Issuer are not Continuing Directors;

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(3) the sale, lease, transfer, conveyance or other disposition (other than by way of merger or consolidation), in one or a series of related transactions, of all or substantially all of the assets of the Issuer and its Restricted Subsidiaries taken as a whole to any “person” (as such term is used in Sections 13(d) and 14(d) of the Exchange Act); or

(4) the adoption by the shareholders of the Issuer of a plan or proposal for the liquidation or dissolution of the Issuer.

“Change of Control Offer” has the meaning provided in Section 4.15.

“Change of Control Payment” has the meaning provided in Section 4.15.

“Change of Control Payment Date” has the meaning provided in Section 4.15.

“Clearstream” means Clearstream Banking, Société Anonyme.

“Code” means the Internal Revenue Code of 1986, as amended.

“Collateral” means all the assets and properties subject to the Liens created by the Security Documents.

“Collateral Agent” means the Trustee or a party selected by the Trustee, acting as the collateral agent for the Holders of the Notes and the Trustee under the Security Documents.

“Commodity Agreements” means, in respect of any Person, any forward contract, commodity swap agreement, commodity option agreement or other similar agreement or arrangement in respect of Hydrocarbons used, produced, processed or sold by such Person entered into in the ordinary course of business and that are designed to protect such Person against fluctuation in Hydrocarbon prices.

“Common Stock” means, with respect to any Person, any and all shares, interests or other participations in, and other equivalents (however designated and whether voting or nonvoting) of such Person’s common stock, whether or not outstanding on the Issue Date, and includes, without limitation, all series and classes of such common stock.

“Consolidated Coverage Ratio” means as of any date of determination, the ratio of (x) the aggregate amount of Consolidated EBITDAX of such Person for the period of the most recent four full consecutive fiscal quarters ending prior to the date of such determination for which financial statements are in existence to (y) Consolidated Interest Expense for such four fiscal quarters, provided, however, that:

(1) if the Issuer or any Restricted Subsidiary:

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(a) has Incurred any Indebtedness since the beginning of such period that remains outstanding on such date of determination or if the transaction giving rise to the need to calculate the Consolidated Coverage Ratio is an Incurrence of Indebtedness, Consolidated EBITDAX and Consolidated Interest Expense for such period will be calculated after giving effect on a pro forma basis to such Indebtedness and the use of proceeds thereof as if such Indebtedness had been Incurred on the first day of such period and such proceeds had been applied as of such date (except that in making such computation, the amount of Indebtedness under any revolving Credit Facility outstanding on the date of such calculation will be deemed to be (i) the average daily balance of such Indebtedness during such four fiscal quarters or such shorter period for which such facility was outstanding or (ii) if such facility was created after the end of such four fiscal quarters, the average daily balance of such Indebtedness during the period from the date of creation of such revolving Credit Facility to the date of such calculation, in each case, provided that such average daily balance shall take into account any repayment of Indebtedness under such revolving Credit Facility as provided in clause (b)); or

(b) has repaid, repurchased, defeased or otherwise discharged any Indebtedness since the beginning of the period, including with the proceeds of such new Indebtedness, that is no longer outstanding on such date of determination or if the transaction giving rise to the need to calculate the Consolidated Coverage Ratio involves a discharge of Indebtedness (in each case other than Indebtedness Incurred under any revolving Credit Facility unless such Indebtedness has been permanently repaid and the related commitment terminated), Consolidated EBITDAX and Consolidated Interest Expense for such period will be calculated after giving effect on a pro forma basis to such discharge of such Indebtedness as if such discharge had occurred on the first day of such period;

(2) if, since the beginning of such period, the Issuer or any Restricted Subsidiary has made any Asset Disposition or if the transaction giving rise to the need to calculate the Consolidated Coverage Ratio is such an Asset Disposition, the Consolidated EBITDAX for such period will be reduced by an amount equal to the Consolidated EBITDAX (if positive) directly attributable to the assets which are the subject of such Asset Disposition for such period or increased by an amount equal to the Consolidated EBITDAX (if negative) directly attributable thereto for such period and Consolidated Interest Expense for such period shall be reduced by an amount equal to the Consolidated Interest Expense directly attributable to any Indebtedness of the Issuer or any Restricted Subsidiary repaid, repurchased, defeased or otherwise discharged with respect to the Issuer and its continuing Restricted Subsidiaries in connection with or with the proceeds from such Asset Disposition for such period (or, if the Capital Stock

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of any Restricted Subsidiary is sold, the Consolidated Interest Expense for such period directly attributable to the Indebtedness of such Restricted Subsidiary to the extent the Issuer and its continuing Restricted Subsidiaries are no longer liable for such Indebtedness after such sale);

(3) if, since the beginning of such period, the Issuer or any Restricted Subsidiary (by merger or otherwise) has made an Investment in any Restricted Subsidiary (or any Person which becomes a Restricted Subsidiary or is merged with or into the Issuer or a Restricted Subsidiary) or an acquisition (or will have received a contribution) of assets, including any acquisition or contribution of assets occurring in connection with a transaction causing a calculation to be made hereunder, which constitutes, all or substantially all of a company, division, operating unit, segment, business, group of related assets or line of business, Consolidated EBITDAX and Consolidated Interest Expense for such period will be calculated after giving pro forma effect thereto (including the Incurrence of any Indebtedness) as if such Investment or acquisition or contribution had occurred on the first day of such period; and

(4) if, since the beginning of such period, any Person (that subsequently became a Restricted Subsidiary or was merged with or into the Issuer or any Restricted Subsidiary since the beginning of such period) made any Asset Disposition or any Investment or acquisition of assets that would have required an adjustment pursuant to clause (2) or (3) above if made by the Issuer or a Restricted Subsidiary during such period, Consolidated EBITDAX and Consolidated Interest Expense for such period will be calculated after giving pro forma effect thereto as if such Asset Disposition or Investment or acquisition of assets had occurred on the first day of such period.

For purposes of this definition, whenever pro forma effect is to be given to any calculation under this definition, the pro forma calculations will be determined in good faith by a responsible financial or accounting Officer of the Issuer provided that such Officer may in his or her discretion include any reasonably identifiable and factually supportable pro forma changes to Consolidated EBITDAX, including any pro forma expenses and cost reductions, that have occurred or in the judgment of such Officer are reasonably expected to occur within 12 months of the date of the applicable transaction to the extent that such expense or cost reduction or any other operating improvements could then be reflected properly in pro forma financial statements prepared in accordance with Regulation S-X under the Securities Act or any other regulation or policy of the SEC. If any Indebtedness bears a floating rate of interest and is being given pro forma effect, the interest expense on such Indebtedness will be calculated as if the average rate in effect from the beginning of such period to the date of determination had been the applicable rate for the entire period (taking into account any Interest Rate Agreement applicable to such Indebtedness, but if the remaining term of such Interest Rate Agreement is less than 12 months, then such Interest Rate Agreement shall only be taken into account for that portion of the period equal to the remaining term thereof). If any Indebt-

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edness that is being given pro forma effect bears an interest rate at the option of the Issuer, the interest rate shall be calculated by applying such optional rate chosen by the Issuer. Interest on Indebtedness that may optionally be determined at an interest rate based upon a factor of a prime or similar rate, a eurocurrency interbank offered rate, or other rate, shall be deemed to have been based upon the rate actually chosen, or, if none, then based upon such optional rate chosen as the Issuer may designate.

“Consolidated EBITDAX” for any period means, without duplication, the Consolidated Net Income for such period, plus the following, (a) increased by, without duplication and to the extent deducted (and not added back) in calculating such Consolidated Net Income:

(1) Consolidated Interest Expense;

(2) Consolidated Income Taxes of the Issuer and its Restricted Subsidiaries paid or accrued in accordance with GAAP for such period;

(3) consolidated depletion and depreciation expense of the Issuer and its Restricted Subsidiaries;

(4) consolidated amortization expense or impairment charges of the Issuer and its Restricted Subsidiaries recorded in connection with the application of Statement of Financial Accounting Standard No. 142, “Goodwill and Other Intangibles” and Statement of Financial Accounting Standard No. 144, “Accounting for the Impairment or Disposal of Long Lived Assets”;

(5) other non-cash charges of the Issuer and its Restricted Subsidiaries (excluding any such non-cash charge to the extent it represents an accrual of or reserve for cash charges in any future period or amortization of a prepaid cash expense that was paid in a prior period not included in the calculation);

(6) consolidated exploration expense of the Issuer and its Restricted Subsidiaries; and

(b) increased or decreased by, without duplication any gain or loss realized upon the sale or other disposition of any property, plant or equipment of the Issuer or its consolidated Subsidiaries (including pursuant to any Sale/Leaseback Transaction) which is not sold or otherwise disposed of in the ordinary course of business and any gain (loss) realized upon the sale or other disposition of any Capital Stock of any Person, if applicable for such period; and

(c) less, to the extent included in calculating such Consolidated Net Income and in excess of any costs or expenses attributable thereto that were deducted (and not added back) in calculating such Consolidated Net Income, the sum of (x) the amount of deferred revenues that are

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amortized during such period and are attributable to reserves that are subject to Volumetric Production Payments, (y) amounts recorded in accordance with GAAP as repayments of principal and interest pursuant to Dollar-Denominated Production Payments and (z) other non-cash gains (excluding any non-cash gain to the extent it represents the reversal of an accrual or reserve for a potential cash item that reduced Consolidated EBITDAX in any prior period).

Notwithstanding the preceding sentence, clauses (2) through (6) relating to amounts of a Restricted Subsidiary of a Person will be added to Consolidated Net Income to compute Consolidated EBITDAX of such Person only to the extent (and in the same proportion) that the net income (loss) of such Restricted Subsidiary was included in calculating the Consolidated Net Income of such Person and, to the extent the amounts set forth in clauses (2) through (6) are in excess of those necessary to offset a net loss of such Restricted Subsidiary or if such Restricted Subsidiary has net income for such period included in Consolidated Net Income, only if a corresponding amount would be permitted at the date of determination to be dividended to the Issuer by such Restricted Subsidiary without prior approval (that has not been obtained), pursuant to the terms of its charter and all agreements, instruments, judgments, decrees, orders, statutes, rules and governmental regulations applicable to that Restricted Subsidiary or its stockholders.

“Consolidated Income Taxes” means, with respect to any Person for any period, taxes imposed upon such Person or other payments required to be made by such Person by any governmental authority which taxes or other payments are calculated by reference to the income, profits or capital of such Person or such Person and its Restricted Subsidiaries (to the extent such income or profits were included in computing Consolidated Net Income for such period), regardless of whether such taxes or payments are required to be remitted to any governmental authority.

“Consolidated Interest Expense” means, for any period, the total consolidated interest expense of the Issuer and its Restricted Subsidiaries, determined on a consolidated basis in accordance with GAAP, plus, to the extent not included in such interest expense and without duplication:

(1) interest expense for such period attributable to Capitalized Lease Obligations, Synthetic Lease Obligations and the interest component of any deferred payment obligations;

(2) amortization of debt discount and debt issuance cost (provided that any amortization of bond premium will be credited to reduce Consolidated Interest Expense unless, pursuant to GAAP, such amortization of bond premium has otherwise reduced Consolidated Interest Expense);

(3) non-cash interest expense;

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(4) commissions, discounts and other fees and charges owed with respect to Letters of Credit and bankers’ acceptance financing;

(5) the interest expense on Indebtedness of another Person that is Guaranteed by the Issuer or one of its Restricted Subsidiaries or secured by a Lien on assets of the Issuer or one of its Restricted Subsidiaries, to the extent such Guarantee becomes payable or such Lien becomes subject to foreclosure;

(6) costs associated with Interest Rate Agreements (including amortization of fees); provided, however, that if Interest Rate Agreements result in net benefits rather than costs, such benefits shall be credited to reduce Consolidated Interest Expense unless, pursuant to GAAP, such net benefits are otherwise reflected in Consolidated Net Income;

(7) the consolidated interest expense of the Issuer and its Restricted Subsidiaries that was capitalized during such period; and

(8) all dividends paid or payable in cash, Cash Equivalents or Indebtedness or dividends accrued during such period on any Specified Convertible Preferred and on any series of Disqualified Stock (including Cash-Pay Preferred) of the Issuer or on Preferred Stock of its Restricted Subsidiaries payable to a party other than the Issuer or a Wholly-Owned Subsidiary.

minus, to the extent included above, write-off of deferred financing costs (and interest) attributable to Dollar-Denominated Production Payments.

For the purpose of calculating the Consolidated Coverage Ratio in connection with the Incurrence of any Indebtedness described in the final paragraph of the definition of “Indebtedness,” the calculation of Consolidated Interest Expense shall include all interest expense (including any amounts described in clauses (1) through (5) above) relating to any Indebtedness of the Issuer or any Restricted Subsidiary described in the final paragraph of the definition of “Indebtedness.”

“Consolidated Net Income” means, for any period, the aggregate net income (loss) of the Issuer and its consolidated Subsidiaries determined in accordance with GAAP and before any reduction in respect of Preferred Stock dividends of such Person (excluding non-controlling interests); provided, however, that there will not be included (to the extent otherwise included therein) in such Consolidated Net Income:

(1) any net income (loss) of any Person (other than the Issuer) if such Person is not a Restricted Subsidiary, except that:

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(a) subject to the limitations contained in clauses (3) and (4) below, the Issuer’s equity in the net income of any such Person for such period will be included in such Consolidated Net Income up to the aggregate amount of cash actually distributed by such Person during such period to the Issuer or a Restricted Subsidiary as a dividend or other distribution (subject, in the case of a dividend or other distribution to a Restricted Subsidiary, to the limitations contained in clause (2) below); provided that cash dividends from any Infrastructure Subsidiary to the extent that such dividends were funded, directly or indirectly, from the proceeds of debt or equity financing at such Infrastructure Subsidiary shall not be included in such Consolidated Net Income; and

(b) the Issuer’s equity in a net loss of any such Person for such period will be included in determining such Consolidated Net Income to the extent such loss has been funded with cash from the Issuer or a Restricted Subsidiary during such period;

(2) any net income (but not loss) of any Restricted Subsidiary if such Subsidiary is subject to restrictions, directly or indirectly, on the payment of dividends or the making of distributions by such Restricted Subsidiary, directly or indirectly, to the Issuer, except that:

(a) subject to the limitations contained in clauses (3), (4) and (5) below, the Issuer’s equity in the net income of any such Restricted Subsidiary for such period will be included in such Consolidated Net Income up to the aggregate amount of cash that could have been distributed by such Restricted Subsidiary during such period to the Issuer or another Restricted Subsidiary as a dividend or other distribution (subject, in the case of a dividend or other distribution paid to another Restricted Subsidiary, to the limitation contained in this clause); and

(b) the Issuer’s equity in a net loss of any such Restricted Subsidiary for such period will be included in determining such Consolidated Net Income;

(3) any gain (loss) realized upon the sale or other disposition of any property, plant or equipment of the Issuer or its consolidated Subsidiaries (including pursuant to any Sale/Leaseback Transaction) which is not sold or otherwise disposed of in the ordinary course of business and any gain (loss) realized upon the sale or other disposition of any Capital Stock of any Person;

(4) any extraordinary or nonrecurring gains or losses, together with any related provision for taxes on such gains or losses and all related fees and expenses;

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(5) the cumulative effect of a change in accounting principles;

(6) any asset impairment write-downs on Oil and Gas Properties under GAAP or SEC guidelines;

(7) any unrealized non-cash gains or losses or charges in respect of Hedging Obligations (including those resulting from the application of Statement of Financial Accounting Standard No. 133);

(8) income or loss attributable to discontinued operations (including, without limitation, operations disposed of during such period whether or not such operations were classified as discontinued); and

(9) any non-cash compensation charge arising from any grant of stock, stock options or other equity based awards; provided that the proceeds resulting from any such grant will be excluded from Section 4.10(c)(ii).

“Continuing Directors” means, as of any date of determination, any member of the Board of Directors of the Issuer who: (1) was a member of such Board of Directors on the date of this Indenture; or (2) was nominated for election or elected to such Board of Directors with the approval of a majority of the Continuing Directors who were members of such Board of Directors at the time of such nomination or election.

“Corporate Trust Office” means the office of the Trustee at which at any particular time its corporate trust business shall be principally administered, which office at the date of execution of this Indenture is located at ▇▇▇ ▇▇▇▇▇▇ ▇▇▇▇▇▇, ▇▇▇▇ ▇▇▇▇▇, ▇▇▇▇▇▇▇, ▇▇▇▇▇ ▇▇▇▇▇, Attention: Corporate Trust Administration, re: ATP Oil & Gas Corp. or at any other time at such other address as the Trustee may designate from time to time by notice to the Holders and the Issuer.

“Covenant Defeasance” has the meaning set forth in Section 8.1.

“Credit Facility” means, with respect to the Issuer or any Restricted Subsidiary, one or more debt facilities (including, without limitation, the Senior Secured Credit Agreement), indentures or commercial paper facilities providing for revolving credit loans, term loans, receivables financing (including through the sale of receivables to such lenders or to special purpose entities formed to borrow from such lenders against such receivables) or Letters of Credit, together with the related documents thereto (including any guarantees and security documents, whether in effect on the Issue Date or entered into thereafter), in each case as amended, restated, modified, renewed, refunded, replaced or refinanced in whole or in part from time to time (and whether or not with the original administrative agent and lenders or another administrative agent or agents or other lenders and whether provided under the

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original Senior Secured Credit Agreement or any other credit or other agreement or indenture).

“Currency Agreement” means in respect of a Person any foreign exchange contract, currency swap agreement, futures contract, option contract or other similar agreement as to which such Person is a party or a beneficiary.

“Custodian” means any receiver, trustee, assignee, liquidator, sequestrator or similar official under any Bankruptcy Law.

“Default” means any event which is, or after notice or passage of time or both would be, an Event of Default.

“Definitive Note” means a certificated Note registered in the name of the Holder thereof and issued in accordance with Section 2.6(c) hereof, substantially in the form of Exhibit A hereto, except that such Note shall not bear the Global Note Legend.

“Depository” or “DTC” means The Depository Trust Company, its nominees and successors.

“Discharge of First-Lien Obligations” means, except to the extent otherwise provided in Section 5.6 of the Intercreditor Agreement (and subject to Section 6.5 thereof), (a) payment in full in cash of the principal of and interest (including interest accruing on or after the commencement of any Insolvency or Liquidation Proceeding at the rate provided for in the respective First-Lien Document, whether or not such interest would be allowed in any such Insolvency or Liquidation Proceeding) and premium, if any, on all Indebtedness outstanding under the First-Lien Documents, (b) payment in full in cash of all other First-Lien Obligations that are due and payable or otherwise accrued and owing at or prior to the time such principal, interest and premium are paid, (c) termination (without any prior demand for payment thereunder having been made or, if made, with such demand having been fully reimbursed in cash) or cash collateralization (in an amount and manner, and on terms, reasonably satisfactory to the First-Lien Collateral Agent) of all Letters of Credit and Swap Agreements issued or entered into, as the case may be, by any First-Lien Creditor and (d) termination of all other commitments of the First-Lien Creditors under the First-Lien Documents; provided, however, that if the Issuer or any Subsidiary Guarantor subsequently incurs First-Lien Obligations that are secured by Liens on property or assets of the Issuer or any Subsidiary Guarantor of the type constituting the Collateral and the related Liens are incurred in reliance on clause (1) of the definition of Permitted Liens, then any “Discharge of First-Lien Obligations” which occurred prior to the time of such subsequent incurrence of First-Lien Obligations shall be deemed to not have occurred.

“Disqualified Stock” means, with respect to any Person, that portion of Capital Stock of such Person which by its terms (or by the terms of any security into which it is con-

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vertible or for which it is exchangeable) at the option of the holder of the Capital Stock or upon the happening of any event:

(1) matures or is mandatorily redeemable (other than redeemable only for Capital Stock of such Person which is not itself Disqualified Stock) pursuant to a sinking fund obligation or otherwise;

(2) is convertible or exchangeable for Indebtedness or Disqualified Stock (excluding Capital Stock which is convertible or exchangeable solely at the option of the Issuer or a Restricted Subsidiary); or

(3) is redeemable at the sole option of the holder of the Capital Stock in whole or in part,

in each case on or prior to the Stated Maturity of the Notes; provided that only the portion of Capital Stock which so matures or is mandatorily redeemable, is so convertible or exchangeable or is so redeemable at the option of the holder thereof prior to such date will be deemed to be Disqualified Stock; provided further, that any Capital Stock that would constitute Disqualified Stock solely because the holders thereof have the right to require the Issuer to repurchase such Capital Stock upon the occurrence of a change of control or asset sale (each defined in a substantially identical manner to the corresponding definitions in this Indenture) occurring prior to the first anniversary of the Stated Maturity of the Notes shall not constitute Disqualified Stock if (1) the “asset sale” or “change of control” provisions applicable to such Capital Stock are not more favorable to the holders of such Capital Stock than the terms applicable to the Notes and described under Section 4.15 and Section 4.16; and (2) any such requirement only becomes operative after compliance with such terms applicable to the Notes, including the purchase of any Notes tendered pursuant thereto (or concurrently therewith, provided that all of the Notes validly tendered for purchase pursuant to the requirements described under Section 4.15 or Section 4.16).

The amount of any Disqualified Stock that does not have a fixed redemption, repayment or repurchase price will be calculated in accordance with the terms of such Disqualified Stock as if such Disqualified Stock were redeemed, repaid or repurchased on any date on which the amount of such Disqualified Stock is to be determined pursuant to this Indenture; provided, however, that if such Disqualified Stock could not be required to be redeemed, repaid or repurchased at the time of such determination, the redemption, repayment or repurchase price will be the book value of such Disqualified Stock as reflected in the most recent financial statements of such Person.

“Dollar-Denominated Production Payments” means production payment obligations recorded as liabilities in accordance with GAAP, together with all undertakings and obligations in connection therewith.

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“Equity Interests” means Capital Stock and all warrants, options or other rights to acquire Capital Stock (but excluding any debt security that is convertible into, or exchangeable for, Capital Stock).

“Equity Offering” means a public or private offering for cash by the Issuer of Capital Stock (other than Disqualified Stock) other than public offerings registered on Form S-8.

“Euroclear” means Euroclear S.A./N.V., as operator of the Euroclear system.

“Event of Default” has the meaning provided in Section 6.1.

“Excess Proceeds” has the meaning set forth in Section 4.16.

“Exchange Act” means the Securities Exchange Act of 1934, as amended, and the rules and regulations of the SEC promulgated thereunder.

“Exchange Notes” means the Notes issued in the Exchange Offer pursuant to Section 2.6(f) hereof.

“Exchange Offer” has the meaning set forth in the Registration Rights Agreement.

“Exchange Offer Registration Statement” has the meaning set forth in the Registration Rights Agreement.

“First-Lien Administrative Agent” means JPMorgan Chase Bank, N.A., as collateral agent for the First-Lien Creditors, together with any successors and assigns.

“First-Lien Collateral Agent” means JPMorgan Chase Bank, N.A., as collateral agent for the First-Lien Creditors, together with any successors and assigns.

“First-Lien Credit Documents” means the Senior Secured Credit Agreement and the other “Loan Documents” (as such term is defined in the Senior Secured Credit Agreement) and each of the other agreements, documents and instruments providing for or evidencing any other First-Lien Obligation and any other document or instrument executed or delivered at any time in connection with any First-Lien Obligation (including any intercreditor or joinder agreement among holders of First-Lien Obligations but excluding Swap Agreements), to the extent such are effective at the relevant time, as each may be amended, modified, restated, supplemented, replaced and/or Refinanced from time to time.

“First-Lien Creditors” means, at any time, the holders of First-Lien Obligations at such time, including the First-Lien Lenders, the Secured Swap Providers, the Banking Ser-

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vices Providers, the First-Lien Collateral Agent, the First-Lien Administrative Agent and the other agents and arrangers under the Senior Secured Credit Agreement.

“First-Lien Documents” means, collectively, the First-Lien Credit Documents and the Swap Agreements entered into with one or more Secured Swap Providers.

“First-Lien Lenders” means the “Lenders” as such term is defined in the Senior Secured Credit Agreement; provided that the term “First-Lien Lender” shall in any event also include each issuer of Letters of Credit thereunder.

“First-Lien Mortgages” means, collectively, the “Mortgages” (as such term is defined in the Senior Secured Credit Agreement) and each other first-priority preferred mortgage, deed of trust and any other document or instrument under which any Lien on any real property owned by the Issuer or any Subsidiary Guarantor is granted to secure any First-Lien Obligations or under which rights or remedies with respect to any such Liens are governed, as the same may be amended, supplemented, restated, modified and/or Refinanced from time to time.

“First-Lien Obligations” means (i) all obligations outstanding under the Senior Secured Credit Agreement and the other First-Lien Credit Documents incurred under clause (1) of the second paragraph of Section 4.12, (ii) all Secured Hedging Obligations and (iii) all obligations owing to Banking Services Providers for Banking Services. “First-Lien Obligations” shall in any event include: (a) all interest accrued or accruing (or which would, absent commencement of an Insolvency or Liquidation Proceeding (and the effect of provisions such as Section 502(b)(2) of the United States Bankruptcy Code), accrue) on or after the commencement of an Insolvency or Liquidation Proceeding in accordance with the rate specified in the relevant First-Lien Document, whether or not the claim for such interest is allowed as a claim in such Insolvency or Liquidation Proceeding, (b) any and all fees and expenses (including attorneys’ and/or financial consultants’ fees and expenses) incurred by the First-Lien Collateral Agent, the First-Lien Administrative Agent and the other First-Lien Creditors on or after the commencement of an Insolvency or Liquidation Proceeding, whether or not the claim for fees and expenses is allowed under Section 506(b) of the United States Bankruptcy Code or any other provision of the United States Bankruptcy Code or bankruptcy law as a claim in such Insolvency or Liquidation Proceeding, and (c) all obligations and liabilities of the Issuer and each Subsidiary Guarantor under each First-Lien Document to which it is a party which, but for the automatic stay under Section 362(a) of the United States Bankruptcy Code, would become due.

“First-Lien Pledge Agreements” means, collectively, the “Pledge Agreements” (as such term is defined in the Senior Secured Credit Agreement ) and each other first-priority pledge agreement and any other document or instrument under which any Lien on any Capital Stock held by the Issuer or any Subsidiary Guarantor in any other Subsidiary Guarantor is granted to secure any First-Lien Obligations or under which rights or remedies with respect to

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any such Liens are governed, as the same may be amended, supplemented, restated, modified and/or Refinanced from time to time.

“First-Lien Security Documents” means each First-Lien Mortgage, each First-Lien Pledge Agreement and any other agreement, document, mortgage or instrument pursuant to which a Lien is granted (or purported to be granted) by the Issuer or a Subsidiary Guarantor securing any First-Lien Obligations or under which rights or remedies with respect to such Liens are governed, as the same may be amended, supplemented, restated, modified and/or Refinanced from time to time.

“First-Priority Liens” means all Liens that secure the First-Lien Obligations.

“Foreign Subsidiary” means any Restricted Subsidiary that is not organized under the laws of the United States of America or any state thereof or the District of Columbia.

“GAAP” means generally accepted accounting principles in the United States of America as in effect from time to time. At any time after the Issue Date, the Issuer may elect to apply IFRS accounting principles in lieu of GAAP and, upon any such election, references herein to GAAP shall thereafter be construed to mean IFRS (except as otherwise provided in this Indenture); provided that any such election, once made, shall be irrevocable; provided, further, that any calculation or determination in this Indenture that requires the application of GAAP for periods that include fiscal quarters ended prior to the Issuer’s election to apply IFRS shall remain as previously calculated or determined in accordance with GAAP. The Issuer shall give notice of any such election made in accordance with this definition to the Trustee and the Holders of Notes.

“Global Note” has the meaning provided in Section 2.1.

“Global Note Legend” means the legend set forth in Section 2.15(a)(ii) hereof, which is required to be placed on all Global Notes issued under this Indenture.

“Guarantee” means any obligation, contingent or otherwise, of any Person directly or indirectly guaranteeing any Indebtedness of any other Person and any obligation, direct or indirect, contingent or otherwise, of such Person:

(1) to purchase or pay (or advance or supply funds for the purchase or payment of) such Indebtedness of such other Person (whether arising by virtue of partnership arrangements, or by agreement to keep-well, to purchase assets, goods, securities or services, to take-or-pay, or to maintain financial statement conditions or otherwise); or

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(2) entered into for purposes of assuring in any other manner the obligee of such Indebtedness of the payment thereof or to protect such obligee against loss in respect thereof (in whole or in part);

provided, however, that the term “Guarantee” will not include endorsements for collection or deposit in the ordinary course of business or any obligation to the extent it is payable only in Capital Stock of the Subsidiary Guarantor that is not Disqualified Stock. The term “Guarantee” used as a verb has a corresponding meaning.

“Guarantor Unsecured Obligation” means, with respect to a Subsidiary Guarantor, any Indebtedness of such Subsidiary Guarantor (whether outstanding on the Issue Date or thereafter Incurred) which is not Secured Indebtedness.

“Hedging Obligations” of any Person means the obligations of such Person pursuant to any Interest Rate Agreement, Currency Agreement or Commodity Agreement.

“Holder” means a Person in whose name a Note is registered on the registrar’s books.

“Hydrocarbon Interests” means all rights, titles, interests and estates now or hereafter acquired in and to oil and gas leases, oil, gas and mineral leases, or other liquid or gaseous hydrocarbon leases, mineral fee interests, overriding royalty and royalty interests, net profit interests and production payment interests, including any reserved or residual interests of whatever nature.

“Hydrocarbons” means oil, natural gas, casing head gas, drip gasoline, natural gasoline, condensate, distillate, liquid hydrocarbons, gaseous hydrocarbons and all constituents, elements or compounds thereof and products refined or processed therefrom.

“IFRS” means the International Financial Reporting Standards as adopted by the International Accounting Standards Board.

“Immaterial Subsidiary” means, as of any date, any Restricted Subsidiary whose total assets (based on fair market value), as of that date, are less than $5,000,000 and whose total revenues for the most recent 12-month period do not exceed $5,000,000; provided that a Restricted Subsidiary will not be considered to be an Immaterial Subsidiary if it, directly or indirectly, Guarantees or otherwise provides direct credit support for any Indebtedness of the Issuer.

“Incur” means issue, create, assume, Guarantee, incur or otherwise become directly or indirectly liable for, contingently or otherwise; provided, however, that any Indebtedness or Capital Stock of a Person existing at the time such Person becomes a Restricted Subsidiary (whether by merger, consolidation, acquisition or otherwise) will be deemed to be

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Incurred by such Restricted Subsidiary at the time it becomes a Restricted Subsidiary; and the terms “Incurred” and “Incurrence” have meanings correlative to the foregoing.

“Indebtedness” means, with respect to any Person on any date of determination (without duplication):

(1) the principal of and premium (if any) in respect of indebtedness of such Person for borrowed money;

(2) the principal of and premium (if any) in respect of obligations of such Person evidenced by bonds, debentures, notes or other similar instruments;

(3) the principal component of all obligations of such Person in respect of Letters of Credit, bankers’ acceptances or other similar instruments (including reimbursement obligations with respect thereto except to the extent such reimbursement obligation relates to a trade payable, to the extent such Letters of Credit are not drawn upon or, if and to the extent drawn upon, such obligation is satisfied within 30 days of payment on the letter of credit);

(4) the principal component of all obligations of such Person (other than obligations payable solely in Capital Stock that is not Disqualified Stock) to pay the deferred and unpaid purchase price of property (except as described in clause (8) of the penultimate paragraph of this definition of Indebtedness), which purchase price is due more than six months after the date of placing such property in service or taking delivery and title thereto to the extent such obligations would appear as liabilities upon the consolidated balance sheet of such Person in accordance with GAAP;

(5) Capitalized Lease Obligations and Synthetic Lease Obligations of such Person to the extent such Capitalized Lease Obligations and Synthetic Lease Obligations would appear as liabilities on the consolidated balance sheet of such Person in accordance with GAAP;

(6) the principal component or liquidation preference of all obligations of such Person with respect to the redemption, repayment or other repurchase of any Disqualified Stock (including, for clarification purposes only, Cash-Pay Preferred) or, with respect to any Subsidiary that is not a Subsidiary Guarantor, any Preferred Stock (but excluding, in each case, any accrued dividends);

(7) the principal component of all Indebtedness of other Persons secured by a Lien on any asset of such Person, whether or not such Indebtedness is assumed by such Person; provided, however, that the amount of such Indebtedness will be the lesser of (a) the fair market value of such asset at such date of determination (as deter-

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mined in the good faith by the Board of Directors) and (b) the amount of such Indebtedness of such other Persons so secured;

(8) the principal component of Indebtedness of other Persons to the extent Guaranteed by such Person; and

(9) to the extent not otherwise included in this definition, net obligations of such Person under Commodity Agreements, Currency Agreements and Interest Rate Agreements;

provided, however, that any indebtedness which has been defeased in accordance with GAAP or defeased pursuant to the deposit of cash or Cash Equivalents (in an amount sufficient to satisfy all such indebtedness obligations at maturity or redemption, as applicable, and all payments of interest and premium, if any) in a trust or account created or pledged for the sole benefit of the holders of such indebtedness, and subject to no other Liens, shall not constitute “Indebtedness.”

The amount of Indebtedness of any Person at any date will be the outstanding balance at such date of all unconditional obligations as described above and the maximum liability, upon the occurrence of the contingency giving rise to the obligation, of any contingent obligations at such date.

Notwithstanding the preceding, “Indebtedness” shall not include:

(1) Production Payments and Reserve Sales;

(2) any obligation of a Person in respect of a farm-in agreement or similar arrangement whereby such Person agrees to pay all or a share of the drilling, completion or other expenses of an exploratory or development well (which agreement may be subject to a maximum payment obligation, after which expenses are shared in accordance with the working or participation interest therein or in accordance with the agreement of the parties) or perform the drilling, completion or other operation on such well in exchange for an ownership interest in an oil or gas property;

(3) any obligations under Currency Agreements, Commodity Agreements and Interest Rate Agreements; provided that such Agreements are entered into for bona fide hedging purposes of the Issuer or its Restricted Subsidiaries (as determined in good faith by the Board of Directors or senior management of the Issuer, whether or not accounted for as a hedge in accordance with GAAP) and, in the case of Currency Agreements or Commodity Agreements, such Currency Agreements or Commodity Agreements are related to business transactions of the Issuer or its Restricted Subsidiaries entered into in the ordinary course of business and, in the case of Interest Rate Agreements, such Interest Rate Agreements substantially correspond in terms of no-

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tional amount, duration and interest rates, as applicable, to Indebtedness of the Issuer or its Restricted Subsidiaries Incurred without violation of this Indenture;

(4) any obligation arising from agreements of the Issuer or a Restricted Subsidiary providing for indemnification, Guarantees, adjustment of purchase price, holdbacks, contingency payment obligations or similar obligations (other than Guarantees of Indebtedness), in each case, Incurred or assumed in connection with the acquisition or disposition of any business, assets or Capital Stock of a Restricted Subsidiary, provided that such Indebtedness is not reflected on the face of the balance sheet of the Issuer or any Restricted Subsidiary;

(5) any obligation arising from the honoring by a bank or other financial institution of a check, draft or similar instrument (except in the case of daylight overdrafts) drawn against insufficient funds in the ordinary course of business, provided that such Indebtedness is extinguished within ten business days of Incurrence;

(6) in-kind obligations relating to net oil or natural gas balancing positions arising in the ordinary course of business;

(7) all contracts and other obligations, agreements, instruments or arrangements described in clauses (19), (20), (21), (28)(a) or (29) of the definition of “Permitted Liens.”

(8) accrued expenses and trade payables and other accrued liabilities arising in the ordinary course of business that are not overdue by 90 days past the invoice or billing date or more or are being contested in good faith by appropriate proceedings promptly instituted and diligently conducted; and

(9) Specified Convertible Preferred.

In addition, “Indebtedness” of any Person shall include Indebtedness described in the first paragraph of this definition of “Indebtedness” that would not appear as a liability on the balance sheet of such Person if:

(1) such Indebtedness is the obligation of a partnership or joint venture that is not a Restricted Subsidiary (a “Joint Venture”);

(2) such Person or a Restricted Subsidiary of such Person is a general partner of the Joint Venture or otherwise liable for all or a portion of the Joint Venture’s liabilities (a “General Partner”); and

(3) there is recourse, by contract or operation of law, with respect to the payment of such Indebtedness to property or assets of such Person or a Restricted

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Subsidiary of such Person; and then such Indebtedness shall be included in an amount not to exceed:

(a) the lesser of (i) the net assets of the General Partner and (ii) the amount of such obligations to the extent that there is recourse, by contract or operation of law, to the property or assets of such Person or a Restricted Subsidiary of such Person; or

(b) if less than the amount determined pursuant to clause (a) immediately above, the actual amount of such Indebtedness that is recourse to such Person or a Restricted Subsidiary of such Person, if the Indebtedness is evidenced by a writing and is for a determinable amount.

“Indenture” means this Indenture, as amended or supplemented from time to time in accordance with the terms hereof.

“Indirect Participant” means a Person who holds a beneficial interest in a Global Note through a Participant.

“Infrastructure Subsidiaries” means ATP Infrastructure Partners, L.P., ATP IP-GP, LLC, ATP IP-LP, LLC, ATP Holdco, LLC and any other entity (i) in which the Issuer or any of its Subsidiaries owns Capital Stock and (ii) to which the Issuer or any Restricted Subsidiary has transferred or transfers any of the following infrastructure assets: ATP Innovator drilling and production platform and related assets, ATP Titan drilling and production platform and related assets and ATP Octabuoy drilling and production platform and related assets.

“Initial Purchasers” means ▇.▇. ▇▇▇▇▇▇ Securities Inc., Credit Suisse Securities (USA) LLC, Natixis Bleichroeder LLC, Global Hunter Securities, LLC and ▇▇▇▇▇▇ & ▇▇▇▇▇▇▇, LLC.

“Initial Reserve Report” means, collectively, (i) those certain reserve reports which were prepared by ▇▇▇▇▇ ▇▇▇▇▇ Company, L.P., each dated February 3, 2010, and (ii) that certain reserve report which was prepared by Collarini Associates, dated February 15, 2010, evaluating the Oil and Gas Properties of the Issuer and its subsidiaries prepared as of December 31, 2009, or January 1, 2010, as applicable, true and correct copies of which have been delivered to the First-Lien Collateral Agent.

“Insolvency or Liquidation Proceeding” means (a) any voluntary or involuntary case or proceeding under the United States Bankruptcy Code with respect to the Issuer or any Subsidiary Guarantor, (b) any other voluntary or involuntary insolvency, reorganization or bankruptcy case or proceeding, or any receivership, liquidation, reorganization or other similar case or proceeding with respect to the Issuer or any Subsidiary Guarantor or with re-

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spect to a material portion of its respective assets, (c) any liquidation, dissolution, reorganization or winding up of the Issuer or any Subsidiary Guarantor, whether voluntary or involuntary and whether or not involving insolvency or bankruptcy, or (d) any assignment for the benefit of creditors or any other marshalling of assets and liabilities of the Issuer or any Subsidiary Guarantor.

“Intercreditor Agreement” means the Intercreditor Agreement, dated as of the Issue Date, by and among JPMorgan Chase Bank, N.A. in its capacity as administrative agent under the Senior Secured Credit Agreement and the Trustee, the Collateral Agent, the Issuer and the Subsidiary Guarantors.

“interest” when used with respect to any Note means the amount of all interest accruing on such Note, including any Liquidated Damages.

“Interest Payment Date” means the stated maturity of an installment of interest on the Notes.

“Interest Rate Agreement” means with respect to any Person any interest rate protection agreement, interest rate future agreement, interest rate option agreement, interest rate swap agreement, interest rate cap agreement, interest rate collar agreement, interest rate hedge agreement or other similar agreement or arrangement as to which such Person is party or a beneficiary.

“Investment” means, with respect to any Person, all investments by such Person in other Persons (including Affiliates) in the form of any direct or indirect advance, loan or other extensions of credit (including by way of Guarantee or similar arrangement, but excluding any debt or extension of credit represented by a bank deposit other than a time deposit and advances or extensions of credit to customers in the ordinary course of business) or capital contribution to (by means of any transfer of cash or other property to others or any payment for property or services for the account or use of others), or any purchase or acquisition of Capital Stock, Indebtedness or other similar instruments (excluding any interest in a crude oil or natural gas leasehold to the extent constituting a security under applicable law) issued by, such other Person and all other items that are or would be classified as investments on a balance sheet prepared in accordance with GAAP; provided that none of the following will be deemed to be an Investment:

(1) Hedging Obligations entered into in the ordinary course of business and in compliance with this Indenture;

(2) endorsements of negotiable instruments and documents in the ordinary course of business; and

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(3) an acquisition of assets, Capital Stock or other securities by the Issuer or a Subsidiary for consideration to the extent such consideration consists of Common Stock of the Issuer.

The amount of any Investment shall not be adjusted for increases or decreases in value, write-ups, write-downs or write-offs with respect to such Investment.

For purposes of the definition of “Unrestricted Subsidiary,” clause (13) of the definition of “Permitted Investment” and Section 4.10,

(1) “Investment” will include the portion (proportionate to the Issuer’s equity interest in a Restricted Subsidiary to be designated as an Unrestricted Subsidiary) of the fair market value of the net assets of such Restricted Subsidiary at the time that such Restricted Subsidiary is designated an Unrestricted Subsidiary; provided, however, that upon a redesignation of such Subsidiary as a Restricted Subsidiary, the Issuer will be deemed to continue to have a permanent “Investment” in an Unrestricted Subsidiary in an amount (if positive) equal to (a) the Issuer’s “Investment” in such Subsidiary at the time of such redesignation less (b) the portion (proportionate to the Issuer’s equity interest in such Subsidiary) of the fair market value of the net assets of such Subsidiary (as determined by the Board of Directors of the Issuer in good faith) at the time that such Subsidiary is so redesignated a Restricted Subsidiary; provided, further, that the amount of any Investment in an Infrastructure Subsidiary at the time of its designation as an Unrestricted Subsidiary in accordance with the requirements therefor set forth in the definition of “Unrestricted Subsidiary” shall be deemed to be zero dollars; and

(2) any property transferred to or from an Unrestricted Subsidiary will be valued at its fair market value at the time of such transfer, in each case as determined in good faith by the Board of Directors of the Issuer.

“Investment Grade Rating” means a ▇▇▇▇▇’▇ rating of Baa3 or higher or an S&P rating of BBB- or higher.

“Issue Date” means April 23, 2010, the date of original issuance of the Notes.

“Issuer” has the meaning assigned to such term in the introductory paragraph of this Indenture.

“Legal Defeasance” has the meaning set forth in Section 8.1.

“Legal Holiday” has the meaning provided in Section 11.7.

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“Letter of Transmittal” means the letter of transmittal prepared by the Issuer and sent to all Holders of the Notes for use by such Holders in connection with the Exchange Offer.

“Letters of Credit” means “Letters of Credit” as such term is defined in the Senior Secured Credit Agreement.

“Lien” means, with respect to any asset, any mortgage, lien (statutory or otherwise), pledge, hypothecation, charge, security interest, preference, priority or encumbrance of any kind in respect of such asset, whether or not filed, recorded or otherwise perfected under applicable law, including any conditional sale or other title retention agreement, any lease in the nature thereof, any option or other agreement to sell or give a security interest in and any filing of or agreement to give any financing statement under the UCC (or equivalent statutes) of any jurisdiction; provided that in no event shall an operating lease be deemed to constitute a Lien.

“Liquidated Damages” means all liquidated damages then owing pursuant to the Registration Rights Agreement.

“Maturity Date” means May 1, 2015.

“Minority Interest” means the percentage interest represented by any shares of any class of Capital Stock of a Restricted Subsidiary that are not owned by the Issuer or a Restricted Subsidiary.

“Moody’s” means ▇▇▇▇▇’▇ Investors Service, Inc. or any successor to the rating agency business thereof.

“Mortgaged Property” means any Property owned by the Issuer or any Subsidiary Guarantor that is subject to the Liens existing and to exist under the terms of the Security Documents.

“Mortgages” means all mortgages, deeds of trust and similar documents, instruments and agreements (and all amendments, modifications and supplements thereof) creating, evidencing, perfecting or otherwise establishing the Liens on Mortgaged Property to secure payment of the Notes and the Subsidiary Guarantees or any part thereof.

“Net Available Cash” from an Asset Disposition means cash payments received (including any cash payments received by way of deferred payment of principal pursuant to a note or installment receivable or otherwise and net proceeds from the sale or other disposition of any securities received as consideration, but only as and when received, but excluding any other consideration received in the form of assumption by the acquiring Person of

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Indebtedness or other obligations relating to the properties or assets that are the subject of such Asset Disposition or received in any other non-cash form) therefrom, in each case net of:

(1) all legal, accounting, investment banking, title and recording tax expenses, commissions and other fees and expenses Incurred, and all federal, state, provincial, foreign and local taxes required to be paid or accrued as a liability under GAAP (after taking into account any available tax credits or deductions and any tax sharing agreements), as a consequence of such Asset Disposition;

(2) all payments made on any Indebtedness which is secured by any assets subject to such Asset Disposition, in accordance with the terms of any Lien upon such assets, or which must by its terms, or in order to obtain a necessary consent to such Asset Disposition, or by applicable law be repaid out of the proceeds from such Asset Disposition;

(3) all distributions and other payments required to be made to minority interest holders in Subsidiaries or joint ventures or to holders of royalty or similar interests as a result of such Asset Disposition; and

(4) the deduction of appropriate amounts to be provided by the seller as a reserve, in accordance with GAAP, against any liabilities associated with the assets disposed of in such Asset Disposition and retained by the Issuer or any Restricted Subsidiary after such Asset Disposition.

“Net Cash Proceeds,” with respect to any issuance or sale of Capital Stock or any contribution to equity capital, means the cash proceeds of such issuance, sale or contribution net of attorneys’ fees, accountants’ fees, underwriters’ or placement agents’ fees, listing fees, discounts or commissions and brokerage, consultant and other fees and charges actually Incurred in connection with such issuance, sale or contribution and net of taxes paid or payable as a result of such issuance or sale (after taking into account any available tax credit or deductions and any tax sharing arrangements).

“Net Working Capital” means (a) all current assets of the Issuer and its Restricted Subsidiaries, less (b) all current liabilities of the Issuer and its Restricted Subsidiaries, in each case as set forth in the consolidated financial statements of the Issuer prepared in accordance with GAAP, except that non-cash changes to current assets or current liabilities in any period relating to ▇▇▇▇-to-market accounting for derivatives pursuant to FASB 133 and related pronouncements shall not be taken into account.

“Non-Recourse Debt” means Indebtedness of a Person:

(1) as to which neither the Issuer nor any Restricted Subsidiary (a) provides any Guarantee or credit support of any kind (including any undertaking, guaran-

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tee, indemnity, agreement or instrument that would constitute Indebtedness) or (b) is directly or indirectly liable (as a guarantor or otherwise);

(2) no default with respect to which (including any rights that the holders thereof may have to take enforcement action against an Unrestricted Subsidiary) would permit (upon notice, lapse of time or both) any holder of any other Indebtedness of the Issuer or any Restricted Subsidiary to declare a default under such other Indebtedness or cause the payment thereof to be accelerated or payable prior to its stated maturity; and

(3) the explicit terms of which provide there is no recourse against any of the assets of the Issuer or its Restricted Subsidiaries.

“Non-U.S. Person” means a person who is not a U.S. person, as defined in Regulation S.

“Notes” has the meaning provided in the preamble to this Indenture.

“Officer” means the Chairman of the Board, the Chief Executive Officer, the President, the Chief Financial Officer, any Vice President, the Treasurer or the Secretary of the Issuer. Officer of any Subsidiary Guarantor has a correlative meaning.

“Officer’s Certificate” means a certificate signed by an Officer of the Issuer.

“Oil and Gas Business” means: (1) the business of acquiring, exploring, exploiting, developing, producing, operating and disposing of interests in oil, natural gas, liquid natural gas and other Hydrocarbon and mineral properties or products produced in association with any of the foregoing; (2) the business of gathering, marketing, distributing, treating, processing, storing, refining, selling and transporting of any production from such interests or properties and products produced in association therewith and the marketing of oil, natural gas, other Hydrocarbons and minerals obtained from unrelated Persons; (3) any other related energy business, including without limitation power generation and electrical transmission business, directly or indirectly, from oil, natural gas and other Hydrocarbons and minerals produced substantially from properties in which the Issuer or its Restricted Subsidiaries, directly or indirectly, participate; (4) any business relating to oil field sales and service; and (5) any business or activity relating to, arising from, or necessary, appropriate or incidental to the activities described in the foregoing clauses (1) through (4) of this definition.

“Oil and Gas Properties” means (a) Hydrocarbon Interests; (b) the Properties now or hereafter pooled or unitized with Hydrocarbon Interests; (c) all presently existing or future unitization, pooling agreements and declarations of pooled units and the units created thereby (including without limitation all units created under orders, regulations and rules of any governmental authority) which may affect all or any portion of the Hydrocarbon Interests;

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(d) all operating agreements, contracts and other agreements, including production sharing contracts and agreements, which relate to any of the Hydrocarbon Interests or the production, sale, purchase, exchange or processing of Hydrocarbons from or attributable to such Hydrocarbon Interests; (e) all Hydrocarbons in and under and which may be produced and saved or attributable to the Hydrocarbon Interests, including all oil in tanks, and all rents, issues, profits, proceeds, products, revenues and other incomes from or attributable to the Hydrocarbon Interests; (f) all tenements, hereditaments, appurtenances and Properties in any manner appertaining, belonging, affixed or incidental to the Hydrocarbon Interests and (g) all Properties, rights, titles, interests and estates described or referred to above, including any and all Property, real or personal, now owned or hereafter acquired and situated upon, used, held for use or useful in connection with the operating, working or development of any of such Hydrocarbon Interests or Property (excluding drilling rigs, automotive equipment, rental equipment or other personal Property which may be on such premises for the purpose of drilling a well or for other similar temporary uses) and including any and all oil ▇▇▇▇▇, gas ▇▇▇▇▇, injection ▇▇▇▇▇ or other ▇▇▇▇▇, buildings, structures, fuel separators, liquid extraction plants, plant compressors, pumps, pumping units, field gathering systems, tanks and tank batteries, fixtures, valves, fittings, machinery and parts, engines, boilers, meters, apparatus, equipment, appliances, tools, implements, cables, wires, towers, casing, tubing and rods, surface leases, rights-of-way, easements and servitudes together with all additions, substitutions, replacements, accessions and attachments to any and all of the foregoing.

“Opinion of Counsel” means a written opinion from legal counsel who is acceptable to the Trustee. The counsel may be an employee of or counsel to the Issuer or the Trustee.

“Other Second-Lien Obligations” means other Indebtedness of the Issuer and its Restricted Subsidiaries that is equally and ratably secured by the Collateral (and only the Collateral) with the Notes.

“Pari Passu Indebtedness” means Indebtedness that ranks equally in right of payment to the Notes.

“Pari Passu Notes” has the meaning provided in Section 4.16.

“Participant” means, with respect to the Depository, Euroclear or Clearstream, a Person who has an account with the Depository, Euroclear or Clearstream, respectively (and, with respect to DTC, shall include Euroclear and Clearstream).

“Participating Broker-Dealer” has the meaning set forth in the Registration Rights Agreement.

“Paying Agent” has the meaning provided in Section 2.3.

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“Permitted Acquisition Indebtedness” means Indebtedness or Disqualified Stock of the Issuer or any of the Restricted Subsidiaries to the extent such Indebtedness or Disqualified Stock was Indebtedness or Disqualified Stock:

(1) of an acquired Person prior to the date on which such Person became a Restricted Subsidiary as a result of having been acquired and not incurred in contemplation of such acquisition; or

(2) of a Person that was merged, consolidated or amalgamated into the Issuer or a Restricted Subsidiary that was not incurred in contemplation of such merger, consolidation or amalgamation, provided that on the date such Subsidiary became a Restricted Subsidiary or the date such Person was merged, consolidated and amalgamated into the Issuer or a Restricted Subsidiary, as applicable, after giving pro forma effect thereto,

(a) the Restricted Subsidiary or the Issuer, as applicable, would be permitted to Incur at least $1.00 of additional Indebtedness pursuant to the Consolidated Coverage Ratio test described under Section 4.12; or

(b) the Consolidated Coverage Ratio for the Restricted Subsidiary or the Issuer, as applicable, would be greater than the Consolidated Coverage Ratio for such Restricted Subsidiary or the Issuer immediately prior to such transaction.

“Permitted Business Investment” means any Investment made in the ordinary course of, and of a nature that is or shall have become customary in, the Oil and Gas Business including investments or expenditures for actively exploiting, exploring for, acquiring, developing, producing, processing, gathering, marketing, storing, treating or transporting oil, natural gas or other hydrocarbons and minerals through agreements, transactions, interests or arrangements which permit one to share risks or costs, comply with regulatory requirements regarding local ownership or satisfy other objectives customarily achieved through the conduct of the Oil and Gas Business jointly with third parties, including:

(1) ownership interests in oil, natural gas, other hydrocarbons and minerals properties, liquid natural gas facilities, processing facilities, gathering systems, pipelines, storage facilities or related systems or ancillary real property interests;

(2) Investments in the form of or pursuant to operating agreements, working interests, royalty interests, mineral leases, processing agreements, farm-in agreements, farm-out agreements, division orders, contracts for the sale, transportation or exchange of oil, natural gas, other hydrocarbons and minerals, production sharing agreements, participation agreements, development agreements, area of mutual interest agreements, unitization agreements, pooling agreements, joint bidding agreements, service contracts, joint venture agreements, partnership agreements (whether general

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or limited), subscription agreements, stock purchase agreements, stockholder agreements and other similar agreements (including for limited liability companies) with third parties (including Unrestricted Subsidiaries); and

(3) direct or indirect ownership interests in drilling rigs and related equipment, including, without limitation, transportation equipment.

“Permitted Investment” means an Investment by the Issuer or any Restricted Subsidiary in:

(1) the Issuer, a Restricted Subsidiary or a Person which will, upon the making of such Investment, become a Restricted Subsidiary; provided, however, that the primary business of such Restricted Subsidiary is the Oil and Gas Business;

(2) another Person whose primary business is the Oil and Gas Business if as a result of such Investment such other Person becomes a Restricted Subsidiary or is merged or consolidated with or into, or transfers or conveys all or substantially all its assets to, the Issuer or a Restricted Subsidiary and, in each case, any Investment held by such Person; provided that such Investment was not acquired by such Person in contemplation of such acquisition, merger, consolidation or transfer;

(3) cash and Cash Equivalents;

(4) receivables owing to the Issuer or any Restricted Subsidiary created or acquired in the ordinary course of business and payable or dischargeable in accordance with customary trade terms; provided, however, that such trade terms may include such concessionary trade terms as the Issuer or any such Restricted Subsidiary deems reasonable under the circumstances;

(5) payroll, commission, travel, relocation and similar advances to cover matters that are expected at the time of such advances ultimately to be treated as expenses for accounting purposes and that are made in the ordinary course of business;

(6) loans or advances to employees made in the ordinary course of business consistent with past practices of the Issuer or such Restricted Subsidiary in an aggregate amount not to exceed $1.0 million at any time outstanding;

(7) Capital Stock, obligations or securities received in settlement of debts (x) created in the ordinary course of business and owing to the Issuer or any Restricted Subsidiary or in satisfaction of judgments or (y) pursuant to any plan of reorganization or similar arrangement in a bankruptcy or insolvency proceeding;

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(8) Investments made as a result of the receipt of non-cash consideration from an Asset Disposition that was made pursuant to and in compliance with Section 4.16; provided that such securities or other assets received in an Asset Disposition or an exchange or swap of assets shall be pledged as Collateral under the Security Documents to the extent the assets subject to such Asset Disposition or exchange or swap of assets constituted Collateral, with the Lien on such Collateral securing the Notes being of the same priority with respect to the Notes as the Lien on the assets disposed of;

(9) Investments in existence on the Issue Date;

(10) Commodity Agreements, Currency Agreements, Interest Rate Agreements and related Hedging Obligations, which transactions or obligations are Incurred in compliance with Section 4.12;

(11) Guarantees issued in accordance with Section 4.12;

(12) any Asset Swap or acquisition of Additional Assets, in each case, made in accordance with Section 4.16; provided that such securities or other assets received in an Asset Disposition or an exchange or swap of assets shall be pledged as Collateral under the Security Documents to the extent the assets subject to such Asset Disposition or exchange or swap of assets constituted Collateral, with the Lien on such Collateral securing the Notes being of the same priority with respect to the Notes as the Lien on the assets disposed of;

(13) Investments in Infrastructure Subsidiaries at a time when such Infrastructure Subsidiaries are Unrestricted Subsidiaries in an aggregate amount over the term of the Notes not to exceed $100.0 million plus the amount equal to the aggregate net reduction in Permitted Investments made pursuant to this clause (13) resulting from dividends paid to the Issuer or a Restricted Subsidiary by such Infrastructure Subsidiaries with proceeds from debt or equity financings from any third party that is not the Issuer or an Affiliate of the Issuer or a Restricted Subsidiary (the amount of any such dividends shall be deemed to reduce, on a dollar for dollar basis, the aggregate amount of Investments previously made in Infrastructure Subsidiaries pursuant to this clause (13) but such Investment amount, as so reduced, shall not be less than zero unless the increment of such dividends that would have reduced such Investment amount below zero is not otherwise available to make a Restricted Payment pursuant to Section 4.10;

(14) Permitted Business Investments;

(15) any Person where such Investment was acquired by the Issuer or any of its Restricted Subsidiaries (a) in exchange for any other Investment or accounts re-

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ceivable held by the Issuer or any such Restricted Subsidiary in connection with or as a result of a bankruptcy, workout, reorganization or recapitalization of the issuer of such other Investment or accounts receivable or (b) as a result of a foreclosure by the Issuer or any of its Restricted Subsidiaries with respect to any secured Investment or other transfer of title with respect to any secured Investment in default;

(16) any Person to the extent such Investments consist of prepaid expenses, negotiable instruments held for collection and lease, utility and workers’ compensation, performance and other similar deposits made in the ordinary course of business by the Issuer or any Restricted Subsidiary;

(17) Guarantees of performance or other obligations (other than Indebtedness) arising in the ordinary course in the Oil and Gas Business, including obligations under oil and natural gas exploration, development, joint operating, and related agreements and licenses, concessions or operating leases related to the Oil and Gas Business;

(18) Investments for consideration consisting of Capital Stock (other than Disqualified Stock) of the Issuer; and

(19) Investments by the Issuer or any of its Restricted Subsidiaries, together with all other Investments pursuant to this clause (19), in an aggregate amount outstanding at the time of such Investment not to exceed the greater of $40.0 million and 1.0% of the Issuer’s Adjusted Consolidated Net Tangible Assets (with the fair market value (as determined by the Issuer’s Board of Directors in good faith) of such Investment being measured at the time such Investment is made and without giving effect to subsequent changes in value).

“Permitted Liens” means, with respect to any Person:

(1) Liens securing Indebtedness and other obligations under, and related Hedging Obligations and Liens on assets of Restricted Subsidiaries securing Guarantees of Indebtedness and other obligations of the Issuer under, any Credit Facility permitted to be Incurred under this Indenture under the provisions described in clause (1) of the second paragraph of Section 4.12; provided that (a) the Notes and the Subsidiary Guarantees shall be secured by Second-Priority Liens on the property securing such Indebtedness and (b) the holder of such Lien is subject to an intercreditor agreement with the Collateral Agent, consistent with the terms of the Intercreditor Agreement;

(2) pledges or deposits by such Person under workmen’s compensation laws, unemployment insurance laws, social security or old age pension laws or similar legislation, or good faith deposits in connection with bids, tenders, contracts (other

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than for the payment of Indebtedness) or leases to which such Person is a party, or deposits (which may be secured by a Lien) to secure public or statutory obligations of such Person including Letters of Credit and bank guarantees required or requested by the United States, any State thereof or any foreign government or any subdivision, department, agency, organization or instrumentality of any of the foregoing in connection with any contract or statute (including lessee or operator obligations under statutes, governmental regulations, contracts or instruments related to the ownership, exploration and production of oil, natural gas, other hydrocarbons and minerals on State, Federal or foreign lands or waters), or deposits of cash or United States government bonds to secure indemnity performance, surety or appeal bonds or other similar bonds to which such Person is a party, or deposits as security for contested taxes or import or customs duties or for the payment of rent, in each case Incurred in the ordinary course of business;

(3) statutory and contractual Liens of landlords and Liens imposed by law, including carriers’, warehousemen’s, mechanics’, materialmen’s and repairmen’s Liens, in each case for sums not yet due or being contested in good faith by appropriate proceedings if a reserve or other appropriate provisions, if any, as shall be required by GAAP shall have been made in respect thereof and, in the case of Collateral, such proceedings have the effect of preventing the forfeiture or sale of the property or assets subject to such Lien;

(4) Liens for taxes, assessments or other governmental charges or claims not yet due or which are being contested in good faith by appropriate proceedings; provided that appropriate reserves, if any, required pursuant to GAAP have been made in respect thereof and, in the case of Collateral, such proceedings have the effect of preventing the forfeiture or sale of the property or assets subject to such Lien;

(5) Liens in favor of issuers of surety or performance bonds or Letters of Credit or bankers’ acceptances issued pursuant to the request of and for the account of such Person in the ordinary course of its business; provided, however, that such Letters of Credit do not constitute Indebtedness;

(6) survey exceptions, encumbrances, ground leases, easements or reservations of, or rights of others for, licenses, rights of way, sewers, electric lines, telegraph and telephone lines and other similar purposes, or zoning, building codes or other restrictions (including, without limitation, minor defects or irregularities in title and similar encumbrances) as to the use of real properties or Liens incidental to the conduct of the business of such Person or to the ownership of its properties so long as any such survey exceptions, encumbrances, easements or reservations of, or rights of others for, licenses, rights of way, sewers, electric lines, telegraph and telephone lines and other similar purposes, or zoning, building codes or other restrictions are subordinate in all

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respects to the security interests and Liens granted to the Collateral Agent and do not in the aggregate materially adversely affect the value of the assets of such Person and its Restricted Subsidiaries, taken as a whole, or materially impair their use in the operation of the business of such Person;

(7) Liens securing Hedging Obligations so long as the related Indebtedness is, and is permitted to be under this Indenture, secured by a Lien on the same property securing such Hedging Obligation;

(8) leases, licenses, subleases and sublicenses of assets (including, without limitation, real property and intellectual property rights) which do not materially interfere with the ordinary conduct of the business of the Issuer or any of its Restricted Subsidiaries;

(9) prejudgment Liens and judgment Liens not giving rise to an Event of Default;

(10) Liens for the purpose of securing the payment of all or a part of the purchase price of, or Capitalized Lease Obligations, Synthetic Lease Obligations, purchase money obligations or other payments Incurred to finance the acquisition, lease, improvement or construction of or repairs or additions to, assets or property acquired or constructed in the ordinary course of business under the provisions discussed in clause (6) of the second paragraph under Section 4.12; provided that:

(a) the aggregate principal amount of Indebtedness secured by such Liens is otherwise permitted to be Incurred under this Indenture and does not exceed the lesser of the cost or fair market value (as determined by the Issuer’s Board of Directors in good faith) of the assets or property so acquired or constructed; and

(b) such Liens are created within 180 days of the later of the acquisition, lease, completion of improvements, construction, repairs or additions or commencement of full operation of the assets or property subject to such Lien and do not encumber any other assets or property of the Issuer or any Restricted Subsidiary other than such assets or property and assets affixed or appurtenant thereto;

(11) Liens arising solely by virtue of any statutory or common law provisions relating to banker’s Liens, rights of setoff or similar rights and remedies as to deposit accounts or other funds maintained with a depositary institution; provided that:

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(a) such deposit account is not a dedicated cash collateral account and is not subject to restrictions against access by the Issuer in excess of those set forth by regulations promulgated by the Federal Reserve Board; and

(b) such deposit account is not intended by the Issuer or any Restricted Subsidiary to provide collateral to the depository institution;

(12) Liens arising from operating leases entered into by the Issuer and its Restricted Subsidiaries in the ordinary course of business;

(13) Liens existing on the Issue Date (and any extensions, replacements or renewals thereof covering property or assets secured by such Liens on the Issue Date) other than Liens described under clauses (1) and (17) of this definition;

(14) Liens on property or shares of Capital Stock of a Person at the time such Person becomes a Subsidiary; provided, however, that such Liens are not created or Incurred in connection with, or in contemplation of, such other Person becoming a Subsidiary; provided further, however, that any such Lien may not extend to any other property owned by the Issuer or any Restricted Subsidiary (other than assets or property affixed or appurtenant thereto);

(15) Liens on property at the time the Issuer or any of its Subsidiaries acquired the property, including any acquisition by means of a merger or consolidation with or into the Issuer or any of its Subsidiaries; provided, however, that such Liens are not created or Incurred in connection with, or in contemplation of, such acquisition; provided further, however, that such Liens may not extend to any other property owned by the Issuer or any Restricted Subsidiary (other than assets or property affixed or appurtenant thereto);

(16) Liens securing Indebtedness or other obligations of a Subsidiary owing to the Issuer or a Wholly-Owned Subsidiary;

(17) Liens securing the Notes outstanding on the Issue Date and related Subsidiary Guarantees and other obligations under this Indenture, the Security Documents or the Intercreditor Agreement;

(18) Liens securing Refinancing Indebtedness Incurred to refinance Indebtedness secured by a Lien Incurred under clauses (13) or (14) of this definition, provided that any such Lien is limited to all or part of the same property or assets (plus improvements, accessions, proceeds or dividends or distributions in respect thereof) that secured (or, under the written arrangements under which the original Lien arose, could secure) the Indebtedness being refinanced or is in respect of property or assets that is the security for a Permitted Lien hereunder;

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(19) Liens in respect of Production Payments and Reserve Sales, which Liens shall be limited to the property that is the subject of such Production Payments and Reserve Sales;

(20) Liens arising under farm-out agreements, farm-in agreements, division orders, contracts for the sale, purchase, exchange, transportation, gathering or processing of Hydrocarbons, unitizations and pooling designations, declarations, orders and agreements, development agreements, joint venture agreements, partnership agreements, operating agreements, royalties, working interests, net profits interests, joint interest billing arrangements, participation agreements, production sales contracts, area of mutual interest agreements, oil and gas leases, gas balancing or deferred production agreements, injection, repressuring and recycling agreements, salt water or other disposal agreements, seismic or geophysical permits or agreements, and other agreements which are customary in the Oil and Gas Business; provided, however, in all instances that such Liens are limited to the assets that are the subject of the relevant agreement, program, order or contract;

(21) Liens on pipelines or pipeline facilities that arise by operation of law;

(22) Liens securing Indebtedness in an aggregate principal amount outstanding at any one time, added together with all other Indebtedness secured by Liens Incurred pursuant to this clause (22), not to exceed $25.0 million, as determined on the date of Incurrence of such Indebtedness after giving pro forma effect to such Incurrence and the application of the proceeds therefrom;

(23) Liens in favor of the Issuer or any Subsidiary Guarantor;

(24) deposits made in the ordinary course of business to secure liability to insurance carriers;

(25) Liens in favor of customs and revenue authorities arising as a matter of law to secure payment of customs duties in connection with the importation of goods in the ordinary course of business;

(26) Liens deemed to exist in connection with Investments in repurchase agreements permitted in Section 4.12; provided that such Liens do not extend to any assets other than those that are the subject of such repurchase agreement;

(27) Liens encumbering reasonable customary initial deposits and margin deposits and similar Liens attaching to commodity trading accounts or other brokerage accounts incurred in the ordinary course of business and not for speculative purposes;

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(28) any (a) interest or title of a lessor or sublessor under any lease, liens reserved in oil, gas or other Hydrocarbons, minerals, leases for bonus, royalty or rental payments and for compliance with the terms of such leases; (b) restriction or encumbrance that the interest or title of such lessor or sublessor may be subject to (including, without limitation, ground leases or other prior leases of the demised premises, mortgages, mechanics’ liens, tax liens, and easements); or (c) subordination of the interest of the lessee or sublessee under such lease to any restrictions or encumbrance referred to in the preceding clause (b);

(29) Liens (other than Liens securing Indebtedness) on, or related to, assets to secure all or part of the costs incurred in the ordinary course of the Oil and Gas Business for the exploration, drilling, development, production, processing, transportation, marketing, storage or operation thereof;

(30) Liens upon specific items of inventory or other goods and proceeds of any Person securing such Person’s obligations in respect of bankers’ acceptances issued or created for the account of such Person to facilitate the purchase, shipment or storage of such inventory or other goods;

(31) Liens arising under this Indenture in favor of the Trustee or the Collateral Agent for its own benefit and similar Liens in favor of other trustees, agents and representatives arising under instruments governing Indebtedness permitted to be Incurred under this Indenture, provided, however, that such Liens are solely for the benefit of the trustees, agents or representatives in their capacities as such and not for the benefit of the holders of such Indebtedness;

(32) Liens arising from the deposit of funds or securities in trust for the purpose of decreasing or defeasing Indebtedness so long as such deposit of funds or securities and such decreasing or defeasing of Indebtedness are permitted under Section 4.10;

(33) Liens in favor of collecting or payer banks having a right of setoff, revocation, or charge back with respect to money or instruments of the Issuer or any Subsidiary of the Issuer on deposit with or in possession of such bank;

(34) Liens granted in connection with the disposition of an asset in order to protect the economic rights of the purchaser of such asset therein in the event such disposition were recharacterized as a financing transaction in which ownership was retained by the seller of such asset; and

(35) Liens on the Collateral securing Other Second-Lien Obligations; provided that the aggregate principal amount of all Secured Indebtedness shall not exceed the greater of (x) $1,600.0 million and (y) an amount equal to 50.0% of the Issuer’s

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Adjusted Consolidated Net Tangible Assets determined as of the date of Incurrence; provided, further, that the Indebtedness secured by Liens pursuant to this clause (y) shall be incurred pursuant to the first paragraph of Section 4.12.

In each case set forth above, notwithstanding any stated limitation on the assets that may be subject to such Lien, a Permitted Lien on a specified asset or group or type of assets may include Liens on all improvements, additions and accessions thereto and all products and proceeds thereof (including dividends, distributions and increases in respect thereof).

“Person” means any individual, corporation, partnership, joint venture, association, joint-stock company, trust, unincorporated organization, limited liability company, government or any agency or political subdivision hereof or any other entity.

“Pledge Agreements” means all pledges, powers and similar documents, instruments and agreements (and all amendments, modifications and supplements thereof) creating, evidencing, perfecting or otherwise establishing the Liens to secure payment of the Notes and the Subsidiary Guarantees or any party thereof on the Capital Stock owned by the Issuer and the Subsidiary Guarantors which constitutes Collateral.

“Preferred Stock,” as applied to the Capital Stock of any corporation, means Capital Stock of any class or classes (however designated) which is preferred as to the payment of dividends, or as to the distribution of assets upon any voluntary or involuntary liquidation or dissolution of such corporation, over shares of Capital Stock of any other class of such corporation.

“principal” of any Indebtedness (including the Notes) means the principal amount of such Indebtedness.

“Private Placement Legend” means the legend initially set forth on the Notes in the form set forth in Section 2.15(a)(i).

“pro forma” means, with respect to any calculation made or required to be made pursuant to the terms of this Indenture, a calculation in accordance with Article 11 of Regulation S-X under the Securities Act, as determined by the Board of Directors of the Issuer in consultation with its independent public accountants.

“Production Payments and Reserve Sales” means the grant or transfer by the Issuer or a Restricted Subsidiary to any Person of a royalty, overriding royalty, net profits interest, production payment (whether volumetric or dollar-denominated), partnership or other interest in Oil and Gas Properties, reserves or the right to receive all or a portion of the production or the proceeds from the sale of production attributable to such properties where the holder of such interest has recourse solely to such production or proceeds of production, subject to the obligation of the grantor or transferor to operate and maintain, or cause the subject

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interests to be operated and maintained, in a reasonably prudent manner or other customary standard or subject to the obligation of the grantor or transferor to indemnify for environmental, title or other matters customary in the Oil and Gas Business, including any such grants or transfers pursuant to incentive compensation programs on terms that are reasonably customary in the Oil and Gas Business for geologists, geophysicists or other providers of technical services to the Issuer or a Restricted Subsidiary and including overriding royalty interests in the form of net profits interests in Oil and Gas Properties granted to vendors in exchange for Oil and Gas Property development services.

“Property” means, with respect to any Person, any interests of such Person in any kind of property or asset, whether real, personal or mixed, or tangible or intangible, including, without limitation, Capital Stock, partnership interests and other equity or ownership interests in any other Person.

“Qualified Institutional Buyer” or “QIB” shall have the meaning specified in Rule 144A.

“Recognized Value” means, with respect to all Oil and Gas Properties of the Subsidiary Guarantors constituting proved reserves, the discounted present value of the estimated net cash flow to be realized from the production of Hydrocarbons from all such Oil and Gas Properties which the First-Lien Administrative Agent under the Senior Secured Credit Agreement attributes to such Oil and Gas Properties for the purposes of the most recent redetermination of the borrowing base under the Senior Secured Credit Agreement (or for purposes of determining the initial borrowing base in the event no such redetermination has occurred); provided, that if the Senior Secured Credit Agreement is terminated, the Issuer, acting in good faith, shall continue to make redeterminations in the same manner as if the Senior Secured Credit Agreement were still in effect.

“Record Date” means the Record Dates specified in the Notes.

“Redemption Date,” when used with respect to any Note to be redeemed, means the date fixed for such redemption pursuant to this Indenture and the Notes.

“Redemption Price,” when used with respect to any Note to be redeemed, means the price fixed for such redemption, including principal and premium, if any, pursuant to this Indenture and the Notes.

“Refinancing Indebtedness” means Indebtedness that is Incurred to refund, refinance, replace, exchange, renew, repay, extend, prepay, redeem or retire (including pursuant to any defeasance or discharge mechanism) (collectively, “refinance,” “refinances” and “refinanced” shall have correlative meanings) any Indebtedness (including Indebtedness of the Issuer that refinances Indebtedness of any Restricted Subsidiary and Indebtedness of any Restricted Subsidiary that refinances Indebtedness of another Restricted Subsidiary, but exclud-

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ing Indebtedness of a Subsidiary that is not a Restricted Subsidiary that refinances Indebtedness of the Issuer or a Restricted Subsidiary), including Indebtedness that refinances Refinancing Indebtedness, provided, however, that:

(1) the Refinancing Indebtedness has a Stated Maturity no earlier than the Stated Maturity of the Indebtedness being refinanced;

(2) the Refinancing Indebtedness has an Average Life at the time such Refinancing Indebtedness is Incurred that is equal to or greater than the Average Life of the Indebtedness being refinanced;

(3) such Refinancing Indebtedness is Incurred in an aggregate principal amount (or if issued with original issue discount, an aggregate issue price) that is equal to or less than the sum of the aggregate principal amount (or if issued with original issue discount, the aggregate accreted value) then outstanding of the Indebtedness being refinanced (plus, without duplication, any additional Indebtedness Incurred to pay interest, premiums or defeasance costs required by the instruments governing such existing Indebtedness and fees and expenses Incurred in connection therewith); and

(4) if the Indebtedness being Refinanced is (i) Unsecured Indebtedness such Refinancing Indebtedness also constitutes Unsecured Indebtedness, as the case may be, or (ii) contractually subordinated in right of payment to the Notes or the Subsidiary Guarantee, such Refinancing Indebtedness is subordinated in right of payment to the Notes or the Subsidiary Guarantee on terms at least as favorable to the Holders as those contained in the documentation governing the Indebtedness being Refinanced.

“Registrar” has the meaning provided in Section 2.3.

“Registration Rights Agreement” means that certain registration rights agreement dated as of the date hereof by and among the Issuer and the initial purchasers set forth therein.

“Regulation S” means Regulation S under the Securities Act.

“Regulation S Global Note” means a temporary Global Note in the form of Exhibit A hereto bearing the Global Note Legend, the Private Placement Legend and deposited with or on behalf of and registered in the name of the Depository or its nominee, issued in a denomination equal to the outstanding principal amount of the Notes initially sold in reliance on Rule 903.

“Reserve Report” means a report setting forth, as of each December 31st and June 30th, the oil and gas reserves attributable to the proved Oil and Gas Properties of the Issuer and the Subsidiary Guarantors, together with a projection of the rate of production and

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future net income, taxes, operating expenses and capital expenditures with respect thereto as of such date. Until superseded, the Initial Reserve Report will be considered the Reserve Report.

“Restricted Definitive Note” means a Definitive Note bearing the Private Placement Legend.

“Restricted Global Note” means a Global Note bearing the Private Placement Legend.

“Restricted Investment” means any Investment other than a Permitted Investment.

“Restricted Payment” has the meaning set forth in Section 4.10.

“Restricted Period” means the 40-day distribution compliance period as defined in Regulation S.

“Restricted Subsidiary” means any Subsidiary of the Issuer other than an Unrestricted Subsidiary.

“Rule 144” means Rule 144 promulgated under the Securities Act.

“Rule 144A” means Rule 144A promulgated under the Securities Act.

“Rule 903” means Rule 903 promulgated under the Securities Act.

“Rule 904” means Rule 904 promulgated under the Securities Act.

“S&P” means Standard and Poor’s Rating Service, a division of The ▇▇▇▇▇▇-▇▇▇▇ Companies, Inc., or any successor to the rating agency business thereof.

“Sale/Leaseback Transaction” means an arrangement relating to property now owned or hereafter acquired whereby the Issuer or a Restricted Subsidiary transfers such property to a Person and the Issuer or a Restricted Subsidiary leases it from such Person.

“SEC” means the United States Securities and Exchange Commission.

“Second-Lien Creditors” means, at any time, the holders of Second-Lien Obligations at such time, including the Holders of Notes (and any Additional Notes incurred in compliance with this Indenture), the Collateral Agent and the Trustee.

“Second-Lien Notes Documents” means this Indenture, the Notes, the Additional Notes (if any), the Security Documents and each of the other agreements, documents

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and instruments providing for or evidencing any other Second-Lien Obligation, and any other document or instrument executed or delivered at any time in connection with any Second-Lien Obligation, as the same may be amended, restated, supplemented, modified and/or Refinanced from time to time.

“Second-Lien Obligations” means all obligations outstanding under this Indenture and the other Second-Lien Notes Documents. “Second-Lien Obligations” shall in any event include: (a) all interest accrued or accruing (or which would, absent commencement of an Insolvency or Liquidation Proceeding (and the effect of provisions such as Section 502(b)(2) of the United States Bankruptcy Code), accrue) on or after commencement of an Insolvency or Liquidation Proceeding in accordance with the rate specified in the relevant Second-Lien Notes Document whether or not the claim for such interest is allowed as a claim in such Insolvency or Liquidation Proceeding, (b) any and all fees and expenses (including attorneys’ and/or financial consultants’ fees and expenses) incurred by the Collateral Agent and the Second-Lien Creditors on or after the commencement of an Insolvency or Liquidation Proceeding, whether or not the claim for fees and expenses is allowed under Section 506(b) of the United States Bankruptcy Code or any other provision of the United States Bankruptcy Code or bankruptcy law as a claim in such Insolvency or Liquidation Proceeding, and (c) all obligations and liabilities of the Issuer and each Subsidiary Guarantor under each Second-Lien Notes Document to which it is a party which, but for the automatic stay under Section 362(a) of the United States Bankruptcy Code, would become due.

“Second-Priority Liens” means the second-priority liens on and security interests in the Collateral created in favor of the Collateral Agent (although certain Permitted Liens may have a prior lien ranking and Liens on the Collateral securing First-Lien Obligations will have a first-priority Lien on the Collateral).

“Secured Hedging Obligations” means (i) obligations (including obligations which, but for the automatic stay under Section 362(a) of the United States Bankruptcy Code, would become due) and liabilities, whether now existing or hereafter arising (including, without limitation, indemnities, fees and interest thereon and all interest and fees that accrue on or after the commencement of any Insolvency or Liquidation Proceeding at the rate provided for in the respective Swap Agreement, whether or not a claim for post-petition interest or fees is allowed in any such Insolvency or Liquidation Proceeding), of the Issuer or any Subsidiary Guarantor owing to any Secured Swap Provider, now existing or hereafter incurred under, or arising out of or in connection with, each Swap Agreement to which a Secured Swap Provider is a party (including all such obligations and indebtedness under any guarantee of any such Swap Agreement to which the Issuer or such Subsidiary Guarantor is a party but excluding any additional transactions or confirmations entered into (i) after such Secured Swap Provider ceases to be a First-Lien Lender or an Affiliate of a First-Lien Lender or (ii) after assignment by a Secured Swap Provider to another Secured Swap Provider that is not a First-Lien Lender or an Affiliate of a First-Lien Lender) and (ii) all performance and compliance obligations by

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the Issuer or any Subsidiary Guarantor under any Swap Agreement; provided that the Swap Agreements referred to in each of clauses (i) and (ii) above shall be entered into by the Issuer or any Subsidiary Guarantor for non-speculative purposes.

“Secured Indebtedness” means any Indebtedness of the Issuer or any of its Restricted Subsidiaries secured by a Lien.

“Secured Swap Provider” means (i) each Person that is a party to a Swap Agreement with the Issuer or any Subsidiary Guarantor that entered into such Swap Agreement before or while such Person was a First-Lien Lender or an Affiliate of a First-Lien Lender, whether or not such Person at any time ceases to be a First-Lien Lender or an Affiliate of a First-Lien Lender, as the case may be, or (ii) an assignee of any Person described in clause (i) above so long as such assignee is an Approved Counterparty (as such term is defined in the Senior Secured Credit Agreement).

“Securities Act” means the Securities Act of 1933, as amended, and the rules and regulations of the SEC promulgated thereunder.

“Security Documents” means the Mortgages, the Pledge Agreements and other security documents granting a security interest in and Lien on any assets of any Person to secure the obligations under the Notes and the Subsidiary Guarantees, as each may be amended, restated, supplemented or otherwise modified from time to time.

“Senior Secured Credit Agreement” means the $100.0 million senior secured credit facility dated as of the Issue Date to which the Issuer, the Subsidiary Guarantors and ▇.▇. ▇▇▇▇▇▇ Securities Inc., as lead arranger, are parties, including any guarantees, collateral documents, instruments and agreements executed in connection therewith, and any amendments, supplements, modifications, extensions, renewals, restatements, refundings or refinancings thereof and any indentures or credit facilities or commercial paper facilities with banks or other institutional lenders or investors that replace, refund or refinance any part of the loans, notes, other credit facilities or commitments thereunder, including any such replacement, refunding or refinancing facility or indenture that increases the amount borrowable thereunder or alters the maturity thereof (provided that such increase in borrowings is permitted in Section 4.12).

“Shelf Registration Statement” means the Shelf Registration Statement as defined in the Registration Rights Agreement.

“Significant Subsidiary” means any Restricted Subsidiary that would be a “Significant Subsidiary” of the Issuer within the meaning of Rule 1-02 under Regulation S-X promulgated by the SEC, as in effect on the Issue Date.

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“Specified Convertible Preferred” means the Issuer’s 1,400,000 shares of 8% convertible perpetual preferred stock issued September 29, 2009.

“Stated Maturity” means, with respect to any security, the date specified in such security as the fixed date on which the payment of principal of such security is due and payable, including pursuant to any mandatory redemption provision, but shall not include any contingent obligations to repay, redeem or repurchase any such principal prior to the date originally scheduled for the payment thereof.

“Subordinated Obligation” means any Indebtedness of a Person (whether outstanding on the Issue Date or thereafter Incurred) which is expressly subordinate in right of payment to the Notes pursuant to a written agreement.

“Subsidiary” of any Person means (a) any corporation, association or other business entity (other than a partnership, joint venture, limited liability company or similar entity) of which more than 50% of the total ordinary voting power of shares of Capital Stock entitled (without regard to the occurrence of any contingency) to vote in the election of directors, managers or trustees thereof (or Persons performing similar functions) or (b) any partnership, joint venture, limited liability company or similar entity of which more than 50% of the capital accounts, distribution rights, total equity and voting interests or general or limited partnership interests, as applicable, is, in the case of clauses (a) and (b), at the time owned or controlled, directly or indirectly, by (1) such Person, (2) such Person and one or more Subsidiaries of such Person or (3) one or more Subsidiaries of such Person. Unless otherwise specified herein, each reference to a Subsidiary (other than in this definition) will refer to a Subsidiary of the Issuer.

“Subsidiary Guarantee” means, individually, any Guarantee of payment of the Notes by a Subsidiary Guarantor pursuant to the terms of this Indenture and any supplemental indenture thereto, and, collectively, all such Guarantees. Each such Subsidiary Guarantee will be in the form prescribed by this Indenture.

“Subsidiary Guarantors” means any Restricted Subsidiary created or acquired by the Issuer after the Issue Date other than a Foreign Subsidiary and an Immaterial Subsidiary.

“Swap Agreement” means any agreement with respect to Hedging Obligations.

“Synthetic Lease” shall mean, as to any Person, any lease (including leases that may be terminated by the lessee at any time) of any property (whether real, personal or mixed) (a) that is accounted for as an operating lease under GAAP and (b) in respect of which the lessee retains or obtains ownership of the property so leased for U.S. federal income tax purposes, other than any such lease under which such Person is the lessor. For clarification

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purposes only, operating leases that do not also have the characteristics as described in clause (b) above shall not constitute Synthetic Leases.

“Synthetic Lease Obligations” shall mean, as to any Person, an amount equal to the capitalized amount of the remaining lease payments under any Synthetic Lease that would appear on a balance sheet of such Person in accordance with GAAP if such obligations were accounted for as Capitalized Lease Obligations.

“TIA” means the Trust Indenture Act of 1939 (15 U.S.C. §§ 77aaa-77bbbb), as in effect on the date of this Indenture; provided that in the event the Trust Indenture Act of 1939 is amended after such date, “TIA” means, to the extent required by any such amendment, the Trust Indenture Act of 1939 as so amended.

“Treasury Rate” means, as of any Redemption Date, the yield to maturity at the time of computation of United States Treasury securities with a constant maturity (as compiled and published in the most recent Federal Reserve Statistical Release H.15 (519) which has become publicly available at least two Business Days prior to the Redemption Date (or, if such Statistical Release is no longer published, any publicly available source of similar market data)) most nearly equal to the period from the Redemption Date to May 1, 2013; provided, however, that if the period from the Redemption Date to May 1, 2013 is not equal to the constant maturity of a United States Treasury security for which a weekly average yield is given, the Treasury Rate shall be obtained by linear interpolation (calculated to the nearest one-twelfth of a year) from the weekly average yields of United States Treasury securities for which such yields are given, except that if the period from the Redemption Date to May 1, 2013 is less than one year, the weekly average yield on actually traded United States Treasury securities adjusted to a constant maturity of one year shall be used. The Issuer shall (1) calculate the Treasury Rate at least two Business Days preceding the applicable Redemption Date and (2) prior to such Redemption Date deliver an Officer’s Certificate to the Trustee setting forth the Treasury Rate and Applicable Premium and showing the calculation thereof in reasonable detail.

“Trust Officer” means any officer within the Corporate Trust Office including any Vice President, Managing Director, Director, Assistant Vice President, Associate, or any other officer of the Trustee customarily performing functions similar to those performed by any of the above designated officers and also, with respect to a particular matter, any other officer to whom such matter is referred because of such officer’s knowledge and familiarity with the particular subject, or in the case of a successor trustee, an officer assigned to the department, division or group performing the corporation trust work of such successor and assigned to administer this Indenture.

“Trustee” means the party named as such in this Indenture until a successor replaces it in accordance with the provisions of this Indenture and thereafter means such successor.

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“UCC” means the Uniform Commercial Code as in effect in the State of New York, and any successor statute, as in effect from time to time (except that terms used herein which are defined in the Uniform Commercial Code as in effect in the State of New York on the date hereof shall continue to have the same meaning notwithstanding any replacement or amendment of such statute except as the Collateral Agent may otherwise determine).

“Unrestricted Definitive Note” means one or more Definitive Notes that do not bear and are not required to bear the Private Placement Legend.

“Unrestricted Global Note” means a permanent Global Note, substantially in the form of Exhibit A attached hereto, that bears the Global Note Legend and that is deposited with or on behalf of and registered in the name of the Depository, representing Notes that do not bear the Private Placement Legend.

“Unrestricted Subsidiary” means:

(1) ATP Infrastructure Partners, L.P., ATP IP-GP, LLC, ATP IP-LP, LLC and ATP Holdco, LLC and any other Infrastructure Subsidiary, whether in existence on the Issue Date or created thereafter, designated an Unrestricted Subsidiary by the Board of Directors of the Issuer in the manner provided below;

(2) any Subsidiary of the Issuer that at the time of determination shall be designated an Unrestricted Subsidiary by the Board of Directors of the Issuer in the manner provided below; and

(3) any Subsidiary of an Unrestricted Subsidiary.

The Board of Directors of the Issuer may designate any Subsidiary of the Issuer (including any newly acquired or newly formed Subsidiary or a Person becoming a Subsidiary through merger or consolidation or Investment therein) to be an Unrestricted Subsidiary only if (a) such Subsidiary is an Infrastructure Subsidiary and substantially concurrently with such designation such Infrastructure Subsidiary receives debt and/or equity financing from a third party that is not the Issuer, a Restricted Subsidiary of the Issuer or an Affiliate of the Issuer or any Restricted Subsidiary, or (b) such Subsidiary satisfies the following requirements:

(1) such Subsidiary or any of its Subsidiaries does not own any Capital Stock or Indebtedness of or have any Investment in, or own or hold any Lien on any property of, any other Subsidiary of the Issuer which is not a Subsidiary of the Subsidiary to be so designated or otherwise an Unrestricted Subsidiary;

(2) all the Indebtedness of such Subsidiary and its Subsidiaries shall, at the date of designation, and will at all times thereafter, consist of Non-Recourse Debt;

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(3) on the date of such designation, such designation and the Investment of the Issuer or a Restricted Subsidiary in such Subsidiary complies with Section 4.10;

(4) such Subsidiary is a Person with respect to which neither the Issuer nor any of its Restricted Subsidiaries has any direct or indirect obligation:

(a) to subscribe for additional Capital Stock of such Person; or

(b) to maintain or preserve such Person’s financial condition or to cause such Person to achieve any specified levels of operating results; and

(5) on the date such Subsidiary is designated an Unrestricted Subsidiary, such Subsidiary is not a party to any agreement, contract, arrangement or understanding with the Issuer or any Restricted Subsidiary with terms substantially less favorable to the Issuer than those that might have been obtained from Persons who are not Affiliates of the Issuer.

Any such designation by the Board of Directors of the Issuer shall be evidenced to the Trustee by filing with the Trustee a resolution of the Board of Directors of the Issuer giving effect to such designation and an Officer’s Certificate certifying that such designation complies with the foregoing conditions. If, at any time, any Unrestricted Subsidiary would fail to meet the foregoing requirements as an Unrestricted Subsidiary, it shall thereafter cease to be an Unrestricted Subsidiary for purposes of this Indenture and any Indebtedness of such Subsidiary shall be deemed to be Incurred as of such date.

The Board of Directors of the Issuer may designate any Unrestricted Subsidiary to be a Restricted Subsidiary; provided that immediately after giving effect to such designation, no Default or Event of Default shall have occurred and be continuing or would occur as a consequence thereof and the Issuer could Incur at least $1.00 of additional Indebtedness under the first paragraph of Section 4.12 on a pro forma basis taking into account such designation.

The Issuer and its Restricted Subsidiaries shall cause any Infrastructure Subsidiary which obtains proceeds from debt or equity financings to pay dividends to the Issuer or any Restricted Subsidiary in amounts equal to the proceeds of such financings, promptly after the receipt thereof, to the extent that such proceeds are not required for budgeted or otherwise anticipated expenditures by such Infrastructure Subsidiary necessary for the completion and placing in service of any equipment then under construction by such Infrastructure Subsidiary; provided that if the payment of any such dividends were to be unlawful under the laws of the state of incorporation or organization of such Infrastructure Subsidiary, then the payment of such dividends will be deferred until the earliest possible date when the payment of such dividends shall then be lawful. Any dividends so paid to the Issuer or any Restricted Subsidiary in accordance with the preceding sentence shall be deemed to be “Net Available

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Cash” from an “Asset Disposition” and shall be applied pursuant to the requirements of Section 4.16 as if the date of the payment of such dividends were the date of the deemed Asset Disposition except to the extent they constitute a reduction of Permitted Investment made pursuant to clause (13) of the definition thereof.

“Unsecured Indebtedness” means Indebtedness that is not Secured Indebtedness.

“U.S. Government Obligations” means securities that are (a) direct obligations of the United States of America for the timely payment of which its full faith and credit is pledged or (b) obligations of a Person controlled or supervised by and acting as an agency or instrumentality of the United States of America the timely payment of which is unconditionally guaranteed as a full faith and credit obligation of the United States of America, which, in either case, are not callable or redeemable at the option of the issuer thereof, and shall also include a depositary receipt issued by a bank (as defined in Section 3(a)(2) of the Securities Act), as custodian with respect to any such U.S. Government Obligations or a specific payment of principal of or interest on any such U.S. Government Obligations held by such custodian for the account of the holder of such depositary receipt; provided that (except as required by law) such custodian is not authorized to make any deduction from the amount payable to the holder of such depositary receipt from any amount received by the custodian in respect of the U.S. Government Obligations or the specific payment of principal of or interest on the U.S. Government Obligations evidenced by such depositary receipt.

“U.S. Legal Tender” means such coin or currency of the United States of America as at the time of payment shall be legal tender for the payment of public and private debts.

“Volumetric Production Payments” means production payment obligations recorded as deferred revenue in accordance with GAAP, together with all undertakings and obligations in connection therewith.

“Voting Stock” of an entity means all classes of Capital Stock of such entity then outstanding and normally entitled to vote in the election of members of such entity’s Board of Directors.

“Wholly-Owned Subsidiary” means a Restricted Subsidiary, all of the Capital Stock of which (other than directors’ qualifying shares) is owned by the Issuer or another Wholly-Owned Subsidiary.

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SECTION 1.2. Incorporation by Reference of TIA.

Whenever this Indenture refers to a provision of the TIA, such provision is incorporated by reference in, and made a part of, this Indenture. The following TIA terms used in this Indenture have the following meanings:

“indenture securities” means the Notes;

“indenture security holder” means a Holder;

“indenture to be qualified” means this Indenture;

“indenture trustee” or “institutional trustee” means the Trustee;

“obligor” on the indenture securities means the Issuer and the Subsidiary Guarantors or any other obligor on the Notes and the Subsidiary Guarantees.

All other TIA terms used in this Indenture that are defined by the TIA, defined by TIA reference to another statute or defined by SEC rule and not otherwise defined herein have the meanings assigned to them therein.

SECTION 1.3. Rules of Construction.

Unless the context otherwise requires:

(1) a term has the meaning assigned to it;

(2) an accounting term not otherwise defined has the meaning assigned to it in accordance with GAAP;

(3) “or” is not exclusive;

(4) words in the singular include the plural, and words in the plural include the singular;

(5) “herein,” “hereof” and other words of similar import refer to this Indenture as a whole and not to any particular Article, Section or other subdivision; and

(6) any reference to a statute, law or regulation means that statute, law or regulation as amended and in effect from time to time and includes any successor statute, law or regulation; provided, however, that any reference to the Bankruptcy Law shall mean the Bankruptcy Law as applicable to the relevant case.

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ARTICLE II.

THE NOTES

SECTION 2.1. Form and Dating.

(a) General. The Notes and the Trustee’s certificate of authentication relating thereto shall be substantially in the form of Exhibit A hereto. The Notes may have notations, legends or endorsements required by law, stock exchange rule or depository rule or usage. The Issuer shall approve the form of the Notes and any notation, legend or endorsement on them. Each Note shall be dated the date of its issuance and shall show the date of its authentication.

The terms and provisions contained in the Notes, a form of which is annexed hereto as Exhibit A, shall constitute, and are hereby expressly made, a part of this Indenture and, to the extent applicable, the Issuer, the Subsidiary Guarantors and the Trustee, by their execution and delivery of this Indenture, expressly agree to such terms and provisions and to be bound thereby.

(b) Global Notes. Notes issued in global form shall be substantially in the form of Exhibit A (the “Global Note”) attached hereto (including the Global Note Legend thereon). Notes issued in definitive form shall be substantially in the form of Exhibit A attached hereto (but without the Global Note Legend thereon). Each Global Note shall provide that it shall represent up to the aggregate principal amount of Notes from time to time endorsed thereon and that the aggregate principal amount of outstanding Notes represented thereby may from time to time be reduced or increased, as applicable, to reflect exchanges and redemptions. Any endorsement of a Global Note to reflect the amount of any increase or decrease in the aggregate principal amount of outstanding Notes represented thereby shall be made by the Trustee or the Custodian, at the direction of the Trustee, in accordance with instructions given by the Holder thereof as required by Section 2.6 hereof.

(c) Terms. The aggregate principal amount of Notes that may be authenticated and delivered under this Indenture is unlimited.

The Notes shall be subject to repurchase by the Issuer pursuant to a Change of Control Offer as provided in Section 4.15 hereof or an Asset Disposition Offer as provided under Section 4.16 hereof. The Notes shall not be redeemable, other than as provided in Article III.

Additional Notes ranking pari passu with the Notes issued on the Issue Date may be created and issued from time to time by the Issuer without notice to or consent of the Holders and shall be consolidated with and form a single class with the Notes issued on the

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Issue Date and shall have the same terms as to status, redemption or otherwise as the Notes issued on the Issue Date; provided that the Issuer’s ability to issue Additional Notes shall be subject to the Issuer’s compliance with Section 4.12 hereof. Any Additional Notes shall be issued with the benefit of an indenture supplemental to this Indenture.

(d) Euroclear and Clearstream Procedures Applicable. The provisions of the “Operating Procedures of the Euroclear System” and “Terms and Conditions Governing Use of Euroclear” and the “General Terms and Conditions of Clearstream Banking” and “Customer Handbook” of Clearstream shall be applicable to transfers of beneficial interests in the Regulation S Global Note and the Regulation S Global Notes that are held by Participants through Euroclear or Clearstream.

SECTION 2.2. Execution and Authentication; Aggregate Principal Amount.

At least one Officer shall execute the Notes for the Issuer by manual or facsimile signature.

If an Officer whose signature is on a Note or a Subsidiary Guarantee was an Officer at the time of such execution but no longer holds that office or position at the time the Trustee authenticates the Note, the Note shall nevertheless be valid.

A Note shall not be valid until an authorized signatory of the Trustee manually or by facsimile signs the certificate of authentication on the Note. The signature shall be conclusive evidence that the Note has been authenticated under this Indenture.

The Trustee shall authenticate (i) Notes for original issue on the Issue Date in the aggregate principal amount not to exceed $1,500,000,000, (ii) subject to Section 4.12, Additional Notes and (iii) Exchange Notes, in each case, upon a written order of the Issuer in the form of an Officer’s Certificate, (an “Authentication Order”). Each such written order shall specify the amount of Notes to be authenticated and the date on which the Notes are to be authenticated, whether the Notes are to be Notes or Additional Notes and whether the Notes are to be issued as Definitive Notes or Global Notes or such other information as the Trustee may reasonably request. Any Additional Notes shall be part of the same issue as the Notes being issued on the Issue Date and will vote on all matters as one class with the Notes being issued on the Issue Date, including, without limitation, waivers, amendments, redemptions, Change of Control Offers and Asset Disposition Offers. For the purposes of this Indenture, except for Section 4.12, references to the Notes include Additional Notes, if any. In addition, with respect to authentication pursuant to clause (ii) of the first sentence of this paragraph, the first such written order from the Issuer shall be accompanied by an Opinion of Counsel of the Issuer in a form reasonably satisfactory to the Trustee stating that the issuance of the Additional Notes does not give rise to an Event of Default, complies with this Indenture and has been duly authorized by the Issuer.

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The Trustee may appoint an authenticating agent (the “Authenticating Agent”) reasonably acceptable to the Issuer to authenticate Notes. Unless otherwise provided in the appointment, an Authenticating Agent may authenticate Notes whenever the Trustee may do so. Each reference in this Indenture to authentication by the Trustee includes authentication by such Authenticating Agent. An Authenticating Agent has the same rights as an Agent to deal with the Issuer or with any Affiliate of the Issuer.

The Notes shall be issuable in fully registered form only, without coupons, in denominations of at least $2,000 and any integral multiple of $1,000 thereafter.

SECTION 2.3. Registrar and Paying Agent.

The Issuer shall maintain an office or agency where (a) Notes may be presented or surrendered for registration of transfer or for exchange (“Registrar”), (b) Notes may be presented or surrendered for payment (“Paying Agent”) and (c) notices and demands to or upon the Issuer in respect of the Notes and this Indenture may be served. The Registrar shall keep a register of the Notes and of their transfer and exchange. The Issuer, upon prior written notice to the Trustee, may have one or more co-Registrars and one or more additional paying agents reasonably acceptable to the Trustee. The term “Paying Agent” includes any additional Paying Agent. The Issuer may act as Paying Agent, except that, for the purposes of payments on the Notes pursuant to Sections 4.15 and 4.16, neither the Issuer nor any Affiliate of the Issuer may act as Paying Agent.

The Issuer shall enter into an appropriate agency agreement with any Agent not a party to this Indenture, which agreement shall incorporate the provisions of the TIA and implement the provisions of this Indenture that relate to such Agent. The Issuer shall notify the Trustee, in advance, of the name and address of any such Agent. If the Issuer fails to maintain a Registrar or Paying Agent, or fails to give the foregoing notice, the Trustee shall act as such.

The Issuer initially appoints the Trustee as Registrar, Paying Agent and agent for service of demands and notices in connection with the Notes, until such time as the Trustee has resigned or a successor has been appointed. Any of the Registrar, the Paying Agent or any other agent may resign upon 30 days’ prior written notice to the Issuer.

SECTION 2.4. Paying Agent To Hold Assets in Trust.

The Issuer shall require each Paying Agent other than the Trustee to agree in writing that such Paying Agent shall hold in trust for the benefit of the Holders or the Trustee all assets held by the Paying Agent for the payment of principal of, premium, if any, or interest on, the Notes (whether such assets have been distributed to it by the Issuer or any other obligor on the Notes), and the Issuer and the Paying Agent shall notify the Trustee of any Default by the Issuer (or any other obligor on the Notes) in making any such payment. The Is-

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▇▇▇▇ at any time may require a Paying Agent to distribute all assets held by it to the Trustee and account for any assets disbursed and the Trustee may at any time during the continuance of any payment default, upon written request to a Paying Agent, require such Paying Agent to distribute all assets held by it to the Trustee and to account for any assets distributed. If the Issuer acts as Paying Agent, it shall segregate and hold in a separate trust fund for the benefit of the Holders all assets held by it as Paying Agent. Upon distribution to the Trustee of all assets that shall have been delivered by the Issuer to the Paying Agent, the Paying Agent (if other than the Issuer) shall have no further liability for such assets.

SECTION 2.5. Holder Lists.

The Trustee shall preserve in as current a form as is reasonably practicable the most recent list available to it of the names and addresses of the Holders and shall otherwise comply with TIA § 312(a). If the Trustee is not the Registrar, the Issuer shall furnish or cause the Registrar to furnish to the Trustee before each Record Date and at such other times as the Trustee may request in writing a list as of such date and in such form as the Trustee may reasonably require of the names and addresses of the Holders, which list may be conclusively relied upon by the Trustee.

SECTION 2.6. Transfer and Exchange.

(a) Transfer and Exchange of Global Notes. Except as otherwise set forth in this Section 2.6, a Global Note may be transferred, in whole and not in part, only to another nominee of the Depository or to a successor Depository or a nominee of such successor Depository. A beneficial interest in a Global Note may not be exchanged for a Definitive Note unless (i) the Depository (x) notifies the Issuer that it is unwilling or unable to continue as Depository for such Global Note or (y) has ceased to be a clearing agency registered under the Exchange Act and, in either case, a successor Depository is not appointed by the Issuer within 120 days or (ii) there shall have occurred and be continuing a Default with respect to the Notes. Upon the occurrence of any of the preceding events in clause (i) or (ii) above, Definitive Notes delivered in exchange for any Global Note or beneficial interests therein will be registered in the names, and issued in any approved denominations, requested by or on behalf of the Depository (in accordance with its customary procedures). Global Notes also may be exchanged or replaced, in whole or in part, as provided in Sections 2.7 and 2.10 hereof. Every Note authenticated and delivered in exchange for, or in lieu of, a Global Note or any portion thereof, pursuant to this Section 2.6 or Section 2.7 or 2.10 hereof, shall be authenticated and delivered in the form of, and shall be, a Global Note, except for Definitive Notes issued subsequent to any of the preceding events in clause (i) or (ii) above and pursuant to Section 2.6(c) hereof. A Global Note may not be exchanged for another Note other than as provided in this Section 2.6(a); provided, however, beneficial interests in a Global Note may be transferred and exchanged as provided in Section 2.6(b), (c) or (f) hereof.

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(b) Transfer and Exchange of Beneficial Interests in the Global Notes. The transfer and exchange of beneficial interests in the Global Notes shall be effected through the Depository, in accordance with the provisions of this Indenture and the Applicable Procedures. Beneficial interests in the Restricted Global Notes shall be subject to restrictions on transfer comparable to those set forth herein to the extent required by the Securities Act. Transfers of beneficial interests in the Global Notes also shall require compliance with either subparagraph (i) or (ii) below, as applicable, as well as one or more of the other following subparagraphs, as applicable:

(i) Transfer of Beneficial Interests in the Same Global Note. Beneficial interests in any Restricted Global Note may be transferred to Persons who take delivery thereof in the form of a beneficial interest in the same Restricted Global Note in accordance with the transfer restrictions set forth in the Private Placement Legend; provided, however, that prior to the expiration of the Restricted Period, transfers of beneficial interests in the Regulation S Global Note may not be made to a U.S. Person or for the account or benefit of a U.S. Person (other than an Initial Purchaser). Beneficial interests in any Unrestricted Global Note may be transferred to Persons who take delivery thereof in the form of a beneficial interest in an Unrestricted Global Note. No written orders or instructions shall be required to be delivered to the Registrar to effect the transfers described in this Section 2.6(b)(i).

(ii) All Other Transfers and Exchanges of Beneficial Interests in Global Notes. In connection with all transfers and exchanges of beneficial interests that are not subject to Section 2.6(b)(i) hereof, the transferor of such beneficial interest must deliver to the Registrar either (A) (1) a written order from a Participant or an Indirect Participant given to the Depository in accordance with the Applicable Procedures directing the Depository to credit or cause to be credited a beneficial interest in another Global Note in an amount equal to the beneficial interest to be transferred or exchanged and (2) instructions given in accordance with the Applicable Procedures containing information regarding the Participant account to be credited with such increase or (B) (1) a written order from a Participant or an Indirect Participant given to the Depository in accordance with the Applicable Procedures directing the Depository to cause to be issued a Definitive Note in an amount equal to the beneficial interest to be transferred or exchanged and (2) instructions given by the Depository to the Registrar containing information regarding the Person in whose name such Definitive Note shall be registered to effect the transfer or exchange referred to in (1) above; provided that in no event shall Definitive Notes be issued upon the transfer or exchange of beneficial interests in the Regulation S Global Note prior to (A) the expiration of the Restricted Period and (B) the receipt by the Registrar of any certificates required pursuant to Rule 903. Upon consummation of an Exchange Offer by the Issuer in accordance with Section 2.06(f) hereof, the requirements of this Section 2.06(b)(ii) shall be deemed to have been satisfied upon receipt by the Registrar of the instructions con-

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tained in the Letter of Transmittal delivered by the Holder of such beneficial interests in the Restricted Global Notes. Upon satisfaction of all of the requirements for transfer or exchange of beneficial interests in Global Notes contained in this Indenture and the Notes or otherwise applicable under the Securities Act, the Trustee shall adjust the principal amount of the relevant Global Note(s) pursuant to Section 2.6(f) or Section 2.6(g) hereof.

(iii) Transfer of Beneficial Interests to Another Restricted Global Note. A beneficial interest in any Restricted Global Note may be transferred to a Person who takes delivery thereof in the form of a beneficial interest in another Restricted Global Note if the transfer complies with the requirements of Section 2.6(b)(ii) hereof and the Registrar receives the following:

(A) if the transferee will take delivery in the form of a beneficial interest in the 144A Global Note, then the transferor must deliver a certificate in the form of Exhibit B hereto, including the certifications in item (1) thereof; or

(B) if the transferee will take delivery in the form of a beneficial interest in the Regulation S Global Note, then the transferor must deliver a certificate in the form of Exhibit B hereto, including the certifications in item (2) thereof.

(iv) Transfer and Exchange of Beneficial Interests in a Restricted Global Note for Beneficial Interests in an Unrestricted Global Note. A beneficial interest in any Restricted Global Note may be exchanged by any holder thereof for a beneficial interest in an Unrestricted Global Note or transferred to a Person who takes delivery thereof in the form of a beneficial interest in an Unrestricted Global Note if the exchange or transfer complies with the requirements of Section 2.6(b)(ii) hereof and:

(A) such exchange or transfer is effected pursuant to the Exchange Offer and the holder of the beneficial interest to be transferred, in the case of an exchange, or the transferee, in the case of a transfer, certifies in the Letter of Transmittal that it is not (1) a Broker-Dealer, (2) a Person participating in the distribution of the Exchange Notes or (3) a Person who is an affiliate (as defined in Rule 144) of the Issuer;

(B) such transfer is effected pursuant to the Shelf Registration Statement in accordance with the Registration Rights Agreement;

(C) such transfer is effected by a Broker-Dealer pursuant to the Exchange Offer Registration Statement in accordance with the Registration Rights Agreement; or

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(D) the Registrar receives the following:

(1) if the holder of such beneficial interest in a Restricted Global Note proposes to exchange such beneficial interest for a beneficial interest in an Unrestricted Global Note, a certificate from such Holder substantially in the form of Exhibit C hereto, including the certifications in item (1)(a) thereof; or

(2) if the holder of such beneficial interest in a Restricted Global Note proposes to transfer such beneficial interest to a Person who shall take delivery thereof in the form of a beneficial interest in an Unrestricted Global Note, a certificate from such holder in the form of Exhibit B hereto, including the certifications in item (4) thereof;

and, in each case set forth in this Section 2.6(b)(iv), if the Registrar so requests or if the Applicable Procedures so require, an Opinion of Counsel in form reasonably acceptable to the Registrar to the effect that such exchange or transfer is in compliance with the Securities Act and that the restrictions on transfer contained herein and in the Private Placement Legend are no longer required in order to maintain compliance with the Securities Act.

If any such transfer is effected pursuant to this Section 2.6(b)(iv) at a time when an Unrestricted Global Note has not yet been issued, the Issuer shall issue and, upon receipt of an Authentication Order in accordance with Section 2.2 hereof, the Trustee shall authenticate one or more Unrestricted Global Notes in an aggregate principal amount equal to the aggregate principal amount of beneficial interests transferred pursuant to this Section 2.6(b)(iv).

Beneficial interests in an Unrestricted Global Note cannot be exchanged for, or transferred to Persons who take delivery thereof in the form of, a beneficial interest in a Restricted Global Note.

(i) Beneficial Interests in Restricted Global Notes to Restricted Definitive Notes. If any holder of a beneficial interest in a Restricted Global Note proposes to exchange such beneficial interest for a Restricted Definitive Note or to transfer such beneficial interest to a Person who takes delivery thereof in the form of a Restricted Definitive Note, then, upon the occurrence of any of the events in paragraph (i) or (ii) of Section 2.6(a) hereof and receipt by the Registrar of the following documentation:

(A) if the holder of such beneficial interest in a Restricted Global Note proposes to exchange such beneficial interest for a Restricted Definitive Note, a certifi-

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cate from such holder substantially in the form of Exhibit C hereto, including the certifications in item (2)(a) thereof;

(B) if such beneficial interest is being transferred to a QIB in accordance with Rule 144A, a certificate substantially in the form of Exhibit B hereto, including the certifications in item (1) thereof;

(C) if such beneficial interest is being transferred to a Non-U.S. Person in an offshore transaction in accordance with Rule 903 or Rule 904, a certificate substantially in the form of Exhibit B hereto, including the certifications in item (2) thereof;

(D) if such beneficial interest is being transferred pursuant to an exemption from the registration requirements of the Securities Act in accordance with Rule 144, a certificate substantially in the form of Exhibit B hereto, including the certifications in item (3)(a) thereof;

(E) if such beneficial interest is being transferred to the Issuer or any of its Restricted Subsidiaries, a certificate substantially in the form of Exhibit B hereto, including the certifications in item (3)(b) thereof; or

(F) if such beneficial interest is being transferred pursuant to an effective registration statement under the Securities Act, a certificate substantially in the form of Exhibit B hereto, including the certifications in item (3)(c) thereof;

the Trustee shall cause the aggregate principal amount of the applicable Restricted Global Note to be reduced accordingly pursuant to Section 2.6(g) hereof, and the Issuer shall issue and, upon receipt of an Authentication Order in accordance with Section 2.2 hereof, the Trustee shall authenticate and mail to the Person designated in the instructions a Definitive Note in the applicable principal amount. Any Definitive Note issued in exchange for a beneficial interest in a Restricted Global Note pursuant to this Section 2.6(c) shall be registered in such name or names and in such authorized denomination or denominations as the holder of such beneficial interest shall instruct the Registrar through instructions from the Depository and the Participant or Indirect Participant. The Trustee shall mail such Definitive Notes to the Persons in whose names such Notes are so registered. Any Definitive Note issued in exchange for a beneficial interest in a Restricted Global Note pursuant to this Section 2.6(c)(i) shall bear the Private Placement Legend and shall be subject to all restrictions on transfer contained therein.

(ii) Reserved.

(iii) Beneficial Interests in Restricted Global Notes to Unrestricted Definitive Notes. A holder of a beneficial interest in a Restricted Global Note may exchange such beneficial interest for an Unrestricted Definitive Note or may transfer such beneficial interest

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to a Person who takes delivery thereof in the form of an Unrestricted Definitive Note only upon the occurrence of any of the events in subsection (i) or (ii) of Section 2.6(a) hereof and if:

(A) such exchange or transfer is effected pursuant to the Exchange Offer in accordance with the Registration Rights Agreement and the holder of such beneficial interest, in the case of an exchange, or the transferee, in the case of a transfer, certifies in the applicable letter of transmittal that it is not (1) a Broker-Dealer, (2) a Person participating in the distribution of the Exchange Notes or (3) a Person who is an affiliate (as defined in Rule 144) of the Issuer;

(B) such transfer is effected pursuant to a Shelf Registration Statement in accordance with the Registration Rights Agreement;

(C) such transfer is effected by a Broker-Dealer pursuant to the Exchange Offer Registration Statement in accordance with the Registration Rights Agreement; or

(D) the Registrar receives the following:

(1) if the holder of such beneficial interest in a Restricted Global Note proposes to exchange such beneficial interest for an Unrestricted Definitive Note, a certificate from such holder substantially in the form of Exhibit C hereto, including the certifications in item (1)(b) thereof; or

(2) if the holder of such beneficial interest in a Restricted Global Note proposes to transfer such beneficial interest to a Person who shall take delivery thereof in the form of an Unrestricted Definitive Note, a certificate from such holder substantially in the form of Exhibit B hereto, including the certifications in item (4) thereof;

and, in each case set forth in this Section 2.6(b)(iii), if the Registrar so requests or if the Applicable Procedures so require, an Opinion of Counsel in form reasonably acceptable to the Registrar to the effect that such exchange or transfer is in compliance with the Securities Act and that the restrictions on transfer contained herein and in the Private Placement Legend are no longer required in order to maintain compliance with the Securities Act.

(iv) Beneficial Interests in Unrestricted Global Notes to Unrestricted Definitive Notes. If any holder of a beneficial interest in an Unrestricted Global Note proposes to exchange such beneficial interest for a Definitive Note or to transfer such beneficial interest to a Person who takes delivery thereof in the form of a Definitive Note, then, upon the occurrence of any of the events in subsection (i) or (ii) of Section 2.6(a) hereof and satisfaction of the conditions set forth in Section 2.6(b)(ii) hereof, the Trustee shall cause the aggregate prin-

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cipal amount of the applicable Global Note to be reduced accordingly pursuant to Section 2.6(g) hereof, and the Issuer shall issue and, upon receipt of an Authentication Order in accordance with Section 2.2 hereof, the Trustee shall authenticate and mail to the Person designated in the instructions a Definitive Note in the applicable principal amount. Any Definitive Note issued in exchange for a beneficial interest pursuant to this Section 2.6(c)(iv) shall be registered in such name or names and in such authorized denomination or denominations as the holder of such beneficial interest shall instruct the Registrar through instructions from or through the Depository and the Participant or Indirect Participant. The Trustee shall mail such Definitive Notes to the Persons in whose names such Notes are so registered. Any Definitive Note issued in exchange for a beneficial interest pursuant to this Section 2.6(c)(iv) shall not bear the Private Placement Legend.

(d) Transfer and Exchange of Definitive Notes for Beneficial Interests.

(i) Restricted Definitive Notes to Beneficial Interests in Restricted Global Notes. If any Holder of a Restricted Definitive Note proposes to exchange such Note for a beneficial interest in a Restricted Global Note or to transfer such Restricted Definitive Note to a Person who takes delivery thereof in the form of a beneficial interest in a Restricted Global Note, then, upon receipt by the Registrar of the following documentation:

(A) if the Holder of such Restricted Definitive Note proposes to exchange such Note for a beneficial interest in a Restricted Global Note, a certificate from such Holder substantially in the form of Exhibit C hereto, including the certifications in item (2)(b) thereof;

(B) if such Restricted Definitive Note is being transferred to a QIB in accordance with Rule 144A, a certificate substantially in the form of Exhibit B hereto, including the certifications in item (1) thereof;

(C) if such Restricted Definitive Note is being transferred to a Non-U.S. Person in an offshore transaction in accordance with Rule 903 or Rule 904, a certificate substantially in the form of Exhibit B hereto, including the certifications in item (2) thereof;

(D) if such Restricted Definitive Note is being transferred pursuant to an exemption from the registration requirements of the Securities Act in accordance with Rule 144, a certificate substantially in the form of Exhibit B hereto, including the certifications in item (3)(a) thereof;

(E) if such Restricted Definitive Note is being transferred to the Issuer or any of its Restricted Subsidiaries, a certificate substantially in the form of Exhibit B hereto, including the certifications in item (3)(b) thereof; or

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(F) if such Restricted Definitive Note is being transferred pursuant to an effective registration statement under the Securities Act, a certificate substantially in the form of Exhibit B hereto, including the certifications in item (3)(c) thereof;

the Trustee shall cancel the Restricted Definitive Note, increase or cause to be increased the aggregate principal amount of, in the case of clause (A) above, the applicable Restricted Global Note, in the case of clause (B) above, the applicable 144A Global Note, and in the case of clause (C) above, the applicable Regulation S Global Note.

(ii) Restricted Definitive Notes to Beneficial Interests in Unrestricted Global Notes. A Holder of a Restricted Definitive Note may exchange such Note for a beneficial interest in an Unrestricted Global Note or transfer such Restricted Definitive Note to a Person who takes delivery thereof in the form of a beneficial interest in an Unrestricted Global Note only if:

(A) such exchange or transfer is effected pursuant to the Exchange Offer in accordance with the Registration Rights Agreement and the Holder, in the case of an exchange, or the transferee, in the case of a transfer, certifies in the applicable letter of transmittal that it is not (1) a Broker-Dealer, (2) a Person participating in the distribution of the Exchange Notes or (3) a Person who is an affiliate (as defined in Rule 144) of the Issuer;

(B) such transfer is effected pursuant to a Shelf Registration Statement in accordance with the Registration Rights Agreement;

(C) such transfer is effected by a Broker-Dealer pursuant to an Exchange Offer Registration Statement in accordance with the Registration Rights Agreement; or

(D) the Registrar receives the following:

(1) if the Holder of such Definitive Notes proposes to exchange such Notes for a beneficial interest in the Unrestricted Global Note, a certificate from such Holder substantially in the form of Exhibit C hereto, including the certifications in item (1)(c) thereof; or

(2) if the Holder of such Definitive Notes proposes to transfer such Notes to a Person who shall take delivery thereof in the form of a beneficial interest in the Unrestricted Global Note, a certificate from such Holder substantially in the form of Exhibit B hereto, including the certifications in item (4) thereof;

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and, in each case set forth in this Section 2.6(d)(ii), if the Registrar so requests or if the Applicable Procedures so require, an Opinion of Counsel in form reasonably acceptable to the Registrar to the effect that such exchange or transfer is in compliance with the Securities Act and that the restrictions on transfer contained herein and in the Private Placement Legend are no longer required in order to maintain compliance with the Securities Act.

Upon satisfaction of the conditions of any of the subparagraphs in this Section 2.6(d)(ii), the Trustee shall cancel the Definitive Notes and increase or cause to be increased the aggregate principal amount of the Unrestricted Global Note.

(iii) Unrestricted Definitive Notes to Beneficial Interests in Unrestricted Global Notes. A Holder of an Unrestricted Definitive Note may exchange such Note for a beneficial interest in an Unrestricted Global Note or transfer such Definitive Notes to a Person who takes delivery thereof in the form of a beneficial interest in an Unrestricted Global Note at any time. Upon receipt of a request for such an exchange or transfer, the Trustee shall cancel the applicable Unrestricted Definitive Note and increase or cause to be increased the aggregate principal amount of one of the Unrestricted Global Notes.

If any such exchange or transfer from a Definitive Note to a beneficial interest is effected pursuant to subparagraph (ii)(B), (ii)(D) or (iii) above at a time when an Unrestricted Global Note has not yet been issued, the Issuer shall issue and, upon receipt of an Authentication Order in accordance with Section 2.2 hereof, the Trustee shall authenticate one or more Unrestricted Global Notes in an aggregate principal amount equal to the principal amount of Definitive Notes so transferred.

(e) Transfer and Exchange of Definitive Notes for Definitive Notes. Upon request by a Holder of Definitive Notes and such Holder’s compliance with the provisions of this Section 2.6(e), the Registrar shall register the transfer or exchange of Definitive Notes. Prior to such registration of transfer or exchange, the requesting Holder shall present or surrender to the Registrar the Definitive Notes duly endorsed or accompanied by a written instruction of transfer in form satisfactory to the Registrar duly executed by such Holder or by its attorney, duly authorized in writing. In addition, the requesting Holder shall provide any additional certifications, documents and information, as applicable, required pursuant to the following provisions of this Section 2.6(e):

(i) Restricted Definitive Notes to Restricted Definitive Notes. Any Restricted Definitive Note may be transferred to and registered in the name of Persons who take delivery thereof in the form of a Restricted Definitive Note if the Registrar receives the following:

(A) if the transfer will be made to a QIB in accordance with Rule 144A, then the transferor must deliver a certificate substantially in the form of Exhibit B hereto, including the certifications in item (1) thereof;

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(B) if the transfer will be made pursuant to Rule 903 or Rule 904 then the transferor must deliver a certificate in the form of Exhibit B hereto, including the certifications in item (2) thereof; or

(C) if the transfer will be made pursuant to any other exemption from the registration requirements of the Securities Act, then the transferor must deliver a certificate in the form of Exhibit B hereto, including the certifications required by item (3) thereof, if applicable.

(ii) Restricted Definitive Notes to Unrestricted Definitive Notes. Any Restricted Definitive Note may be exchanged by the Holder thereof for an Unrestricted Definitive Note or transferred to a Person or Persons who take delivery thereof in the form of an Unrestricted Definitive Note if:

(B) any such transfer is effected pursuant to the Shelf Registration Statement in accordance with the Registration Rights Agreement;

(C) any such transfer is effected by a Broker-Dealer pursuant to the Exchange Offer Registration Statement in accordance with the Registration Rights Agreement; or

(D) the Registrar receives the following:

(1) if the Holder of such Restricted Definitive Notes proposes to exchange such Notes for an Unrestricted Definitive Note, a certificate from such Holder substantially in the form of Exhibit C hereto, including the certifications in item (1)(d) thereof; or

(2) if the Holder of such Restricted Definitive Notes proposes to transfer such Notes to a Person who shall take delivery thereof in the form of an Unrestricted Definitive Note, a certificate from such Holder substantially in the form of Exhibit B hereto, including the certifications in item (4) thereof;

and, in each case set forth in this Section 2.6(e)(ii), if the Registrar so requests, an Opinion of Counsel in form reasonably acceptable to the Registrar to the effect that

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such exchange or transfer is in compliance with the Securities Act and that the restrictions on transfer contained herein and in the Private Placement Legend are no longer required in order to maintain compliance with the Securities Act.

(iii) Unrestricted Definitive Notes to Unrestricted Definitive Notes. A Holder of Unrestricted Definitive Notes may transfer such Notes to a Person who takes delivery thereof in the form of an Unrestricted Definitive Note. Upon receipt of a request to register such a transfer, the Registrar shall register the Unrestricted Definitive Notes pursuant to the instructions from the Holder thereof.

(f) Exchange Offer. Upon the occurrence of the Exchange Offer in accordance with the Registration Rights Agreement, the Issuer will issue and, upon receipt of an Authentication Order in accordance with Section 2.2 hereof, the Trustee will authenticate:

(i) one or more Unrestricted Global Notes in an aggregate principal amount equal to the principal amount of the beneficial interests in the Restricted Global Notes accepted for exchange in the Exchange Offer by Persons that certify that (A) they are not Broker-Dealers, (B) they are not participating in a distribution of the Exchange Notes and (C) they are not affiliates (as defined in Rule 144) of the Issuer; and

(ii) Unrestricted Definitive Notes in an aggregate principal amount equal to the principal amount of the Restricted Definitive Notes accepted for exchange in the Exchange Offer by Persons that certify that (A) they are not Broker-Dealers, (B) they are not participating in a distribution of the Exchange Notes and (C) they are not affiliates (as defined in Rule 144) of the Issuer.

Concurrently with the issuance of such Notes, the Trustee will cause the aggregate principal amount of the applicable Restricted Global Notes to be reduced accordingly, and the Issuer will execute and the Trustee will authenticate and deliver to the Persons designated by the Holders of Definitive Notes so accepted Unrestricted Definitive Notes in the appropriate principal amount.

(g) Cancellation and/or Adjustment of Global Notes. At such time as all beneficial interests in a particular Global Note have been exchanged for Definitive Notes or a particular Global Note has been redeemed, repurchased or canceled in whole and not in part, each such Global Note shall be returned to or retained and canceled by the Trustee in accordance with Section 2.11 hereof. At any time prior to such cancellation, if any beneficial interest in a Global Note is exchanged for or transferred to a Person who will take delivery thereof in the form of a beneficial interest in another Global Note or for Definitive Notes, the principal amount of Notes represented by such Global Note shall be reduced accordingly and an endorsement shall be made on such Global Note by the Trustee or by the Depository at the direction of the Trustee to reflect such reduction; and if the beneficial interest is being exchanged for or transferred to a Person who will take delivery thereof in the form of a benefi-

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cial interest in another Global Note, such other Global Note shall be increased accordingly and an endorsement shall be made on such Global Note by the Trustee or by the Depository at the direction of the Trustee to reflect such increase.

(h) General Provisions Relating to Transfers and Exchanges.

(i) To permit registrations of transfers and exchanges, the Issuer shall execute and the Trustee shall authenticate Global Notes and Definitive Notes upon receipt of an Authentication Order in accordance with Section 2.2 hereof or at the Registrar’s request.

(ii) No service charge shall be made to a holder of a beneficial interest in a Global Note or to a Holder of a Definitive Note for any registration of transfer or exchange, but the Issuer may require payment of a sum sufficient to cover any transfer tax or similar governmental charge payable in connection therewith (other than any such transfer taxes or similar governmental charge payable upon exchange or transfer pursuant to Sections 2.7, 2.10, 3.7, 4.15, 4.16 and 9.5 hereof).

(iii) Neither the Registrar nor the Issuer shall be required to register the transfer of or exchange any Note selected for redemption in whole or in part, except the unredeemed portion of any Note being redeemed in part.

(iv) All Global Notes and Definitive Notes issued upon any registration of transfer or exchange of Global Notes or Definitive Notes shall be the valid obligations of the Issuer, evidencing the same debt, and entitled to the same benefits under this Indenture, as the Global Notes or Definitive Notes surrendered upon such registration of transfer or exchange.

(v) The Issuer shall not be required (A) to issue, to register the transfer of or to exchange any Notes during a period beginning at the opening of business 15 days before the day of any selection of Notes for redemption under Section 3.2 hereof and ending at the close of business on the day of selection, (B) to register the transfer of or to exchange any Note so selected for redemption in whole or in part, except the unredeemed portion of any Note being redeemed in part or (C) to register the transfer of or to exchange a Note between a Record Date and the next succeeding Interest Payment Date.

(vi) Prior to due presentment for the registration of a transfer of any Note, the Trustee, any Agent and the Issuer may deem and treat the Person in whose name any Note is registered as the absolute owner of such Note for the purpose of receiving payment of principal of (and premium, if any) and interest on such Notes and for all other purposes, and none of the Trustee, any Agent or the Issuer shall be affected by notice to the contrary.

(vii) Upon surrender for registration of transfer of any Note at the office or agency of the Issuer designated pursuant to Section 4.2 hereof, the Issuer shall execute, and the Trustee shall authenticate and mail, in the name of the designated transferee or transferees,

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one or more replacement Notes of any authorized denomination or denominations of a like aggregate principal amount.

(viii) At the option of the Holder, Notes may be exchanged for other Notes of any authorized denomination or denominations of a like aggregate principal amount upon surrender of the Notes to be exchanged at such office or agency. Whenever any Global Notes or Definitive Notes are so surrendered for exchange, the Issuer shall execute, and the Trustee shall authenticate and mail, the replacement Global Notes and Definitive Notes which the Holder making the exchange is entitled to in accordance with the provisions of Section 2.2 hereof.

(ix) All certifications, certificates and Opinions of Counsel required to be submitted to the Registrar pursuant to this Section 2.6 to effect a registration of transfer or exchange may be submitted by facsimile.

SECTION 2.7. Replacement Notes.

If a mutilated Note is surrendered to the Trustee or if the Holder of a Note claims that the Note has been lost, destroyed or wrongfully taken, the Issuer shall issue and, upon receipt of an Authentication Order in accordance with Section 2.2 hereof, the Trustee shall authenticate a replacement Note and the Subsidiary Guarantors shall execute a Subsidiary Guarantee thereon if the Trustee’s requirements are met. If required by the Trustee or the Issuer, such Holder must provide an indemnity bond or other indemnity of reasonable tenor, sufficient in the reasonable judgment of the Issuer, the Subsidiary Guarantors and the Trustee, to protect the Issuer, the Subsidiary Guarantors, the Trustee or any Agent from any loss which any of them may suffer if a Note is replaced. Every replacement Note shall constitute an additional obligation of the Issuer and the Subsidiary Guarantors.

SECTION 2.8. Outstanding Notes.

Notes outstanding at any time are all the Notes that have been authenticated by the Trustee except those canceled by it, those delivered to it for cancellation, those reductions in the interest in a Global Note effected by the Trustee in accordance with the provisions hereof and those described in this Section as not outstanding. Subject to the provisions of Section 2.9, a Note does not cease to be outstanding because the Issuer or any of its Affiliates holds the Note.

If a Note is replaced pursuant to Section 2.7 (other than a mutilated Note surrendered for replacement), it ceases to be outstanding unless the Trustee receives proof satisfactory to it that the replaced Note is held by a bona fide purchaser for value. A mutilated Note ceases to be outstanding upon surrender of such Note and replacement thereof pursuant to Section 2.7.

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If on a Redemption Date or the Maturity Date the Paying Agent (other than the Issuer, a Subsidiary or an Affiliate of any thereof) holds U.S. Legal Tender or U.S. Government Obligations sufficient to pay all of the principal, premium, if any, and interest due on the Notes payable on that date and is not prohibited from paying such money to the Holders thereof pursuant to the terms of this Indenture, then on and after that date such Notes shall be deemed not to be outstanding and interest on them shall cease to accrue.

SECTION 2.9. Treasury Notes.

In determining whether the Holders of the required principal amount of Notes have concurred in any direction, waiver, consent or notice, Notes owned by the Issuer or any Subsidiary Guarantor or an Affiliate of the Issuer or any Subsidiary Guarantor shall be considered as though they are not outstanding, except that for the purposes of determining whether the Trustee shall be protected in relying on any such direction, waiver or consent, only Notes which a Trust Officer of the Trustee actually knows are so owned shall be so considered. The Issuer shall notify the Trustee, in writing, when, to its knowledge, any of its Affiliates repurchase or otherwise acquire Notes, of the aggregate principal amount of such Notes so repurchased or otherwise acquired and such other information as the Trustee may reasonably request and the Trustee shall be entitled to rely thereon.

SECTION 2.10. Temporary Notes.

Until definitive Notes are ready for delivery, the Issuer may prepare and the Trustee shall authenticate temporary Notes upon receipt of a written order of the Issuer in the form of an Officer’s Certificate. The Officer’s Certificate shall specify the amount of temporary Notes to be authenticated and the date on which the temporary Notes are to be authenticated. Temporary Notes shall be substantially in the form of definitive Notes but may have variations that the Issuer considers appropriate for temporary Notes and so indicate in the Officer’s Certificate. Without unreasonable delay, the Issuer shall prepare, the Trustee shall authenticate and the Subsidiary Guarantors shall execute Subsidiary Guarantees on, upon receipt of an Authentication Order pursuant to Section 2.2, definitive Notes in exchange for temporary Notes.

SECTION 2.11. Cancellation.

The Issuer at any time may deliver Notes to the Trustee for cancellation. The Registrar and the Paying Agent shall forward to the Trustee any Notes surrendered to them for transfer, exchange or payment. The Trustee, or at the direction of the Trustee, the Registrar or the Paying Agent, and no one else, shall cancel and, at the written direction of the Issuer, shall dispose, in its customary manner, of all Notes surrendered for transfer, exchange, payment or cancellation. The Trustee shall maintain a record of all canceled Notes. Subject to Section 2.7, the Issuer may not issue new Notes to replace Notes that it has paid or delivered to the Trustee for cancellation. If the Issuer shall acquire any of the Notes, such acquisition shall

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not operate as a redemption or satisfaction of the Indebtedness represented by such Notes unless and until the same are surrendered to the Trustee for cancellation pursuant to this Section 2.11.

SECTION 2.12. Reserved.

SECTION 2.13. CUSIP Number.

The Issuer in issuing the Notes may use a “CUSIP” number, and, if so, the Trustee shall use the CUSIP number in notices of redemption or exchange as a convenience to Holders; provided, however, that no representation is hereby deemed to be made by the Trustee as to the correctness or accuracy of the CUSIP number printed in the notice or on the Notes, and that reliance may be placed only on the other identification numbers printed on the Notes. The Issuer shall promptly notify the Trustee of any change in the CUSIP number.

SECTION 2.14. Deposit of Monies.

Prior to 11:00 a.m. New York City time on each Interest Payment Date, Maturity Date, Redemption Date, Change of Control Payment Date and Asset Disposition Purchase Date, the Issuer shall have deposited with the Paying Agent in immediately available funds money sufficient to make cash payments, if any, due on such Interest Payment Date, Maturity Date, Redemption Date, Change of Control Payment Date and Asset Disposition Purchase Date, as the case may be, in a timely manner which permits the Paying Agent to remit payment to the Holders on such Interest Payment Date, Maturity Date, Redemption Date, Change of Control Payment Date and Asset Disposition Purchase Date, as the case may be.

SECTION 2.15. Restrictive Legends.

(a) Legends. The following legends shall appear on the face of all Global Notes and Definitive Notes issued under this Indenture unless specifically stated otherwise in the applicable provisions of this Indenture:

(i) Private Placement Legend.

(A) Except as permitted by subparagraph (B) below, each Global Note and each Definitive Note (and all Notes issued in exchange therefor or substitution thereof) shall bear the legend in substantially the following form:

“THIS SECURITY HAS NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE “SECURITIES ACT”), OR THE SECURITIES LAWS OF ANY STATE OR OTHER JURISDICTION. NEITHER THIS SECURITY NOR ANY INTEREST OR PARTICIPATION HEREIN MAY BE REOFFERED, SOLD,

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ASSIGNED, TRANSFERRED, PLEDGED, ENCUMBERED OR OTHERWISE DISPOSED OF IN THE ABSENCE OF SUCH REGISTRATION OR UNLESS SUCH TRANSACTION IS EXEMPT FROM, OR NOT SUBJECT TO, SUCH REGISTRATION. THE HOLDER OF THIS SECURITY, BY ITS ACCEPTANCE HEREOF, AGREES ON ITS OWN BEHALF AND ON BEHALF OF ANY INVESTOR ACCOUNT FOR WHICH IT HAS PURCHASED SECURITIES, TO OFFER, SELL OR OTHERWISE TRANSFER SUCH SECURITY, PRIOR TO THE DATE (THE “RESALE RESTRICTION TERMINATION DATE”) THAT IS IN THE CASE OF RULE 144A NOTES: ONE YEAR (OR SUCH SHORTER PERIOD THEN REQUIRED UNDER RULE 144 OR ITS SUCCESSOR RULE) IN THE CASE OF REGULATION S NOTES: 40 DAYS AFTER THE LATER OF THE ORIGINAL ISSUE DATE HEREOF AND THE LAST DATE ON WHICH THE ISSUER OR ANY AFFILIATE OF THE ISSUER WAS THE OWNER OF THIS SECURITY (OR ANY PREDECESSOR OF SUCH SECURITY), ONLY (A) TO THE ISSUER, (B) PURSUANT TO A REGISTRATION STATEMENT THAT HAS BEEN DECLARED EFFECTIVE UNDER THE SECURITIES ACT, (C) FOR SO LONG AS THE SECURITIES ARE ELIGIBLE FOR RESALE PURSUANT TO RULE 144A UNDER THE SECURITIES ACT, TO A PERSON IT REASONABLY BELIEVES IS A “QUALIFIED INSTITUTIONAL BUYER” AS DEFINED IN RULE 144A UNDER THE SECURITIES ACT THAT PURCHASES FOR ITS OWN ACCOUNT OR FOR THE ACCOUNT OF A QUALIFIED INSTITUTIONAL BUYER TO WHOM NOTICE IS GIVEN THAT THE TRANSFER IS BEING MADE IN RELIANCE ON RULE 144A, (D) PURSUANT TO OFFERS AND SALES THAT OCCUR OUTSIDE THE UNITED STATES WITHIN THE MEANING OF REGULATION S UNDER THE SECURITIES ACT, OR (E) PURSUANT TO ANOTHER AVAILABLE EXEMPTION FROM THE REGISTRATION REQUIREMENTS OF THE SECURITIES ACT, SUBJECT TO THE ISSUER’S AND THE TRUSTEE’S RIGHT PRIOR TO ANY SUCH OFFER, SALE OR TRANSFER PURSUANT TO THIS CLAUSE (E) TO REQUIRE THE DELIVERY OF AN OPINION OF COUNSEL, CERTIFICATION AND/OR OTHER INFORMATION SATISFACTORY TO EACH OF THEM. THIS LEGEND WILL BE REMOVED UPON THE REQUEST OF THE HOLDER AFTER THE RESALE RESTRICTION TERMINATION DATE.”

(B) Notwithstanding the foregoing, any Global Note or Definitive Note issued pursuant to subparagraph (b)(iv), (c)(iii), (c)(iv), (d)(ii), (d)(iii), (e)(ii), (e)(iii) or

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(f) of Section 2.6 (and all Notes issued in exchange therefor or substitution thereof) shall not bear the Private Placement Legend.

(ii) Global Note Legend. Each Global Note shall bear a legend in substantially the following form:

“THIS GLOBAL NOTE IS HELD BY THE DEPOSITORY (AS DEFINED IN THE INDENTURE GOVERNING THIS NOTE) OR ITS NOMINEE IN CUSTODY FOR THE BENEFIT OF THE BENEFICIAL OWNERS HEREOF, AND IS NOT TRANSFERABLE TO ANY PERSON UNDER ANY CIRCUMSTANCES EXCEPT THAT (I) THE TRUSTEE MAY MAKE SUCH NOTATIONS HEREON AS MAY BE REQUIRED PURSUANT TO SECTION 2.6(f) OR SECTION 2.6(g) OF THE INDENTURE, (II) THIS GLOBAL NOTE MAY BE EXCHANGED IN WHOLE BUT NOT IN PART PURSUANT TO SECTION 2.6(a) OF THE INDENTURE, (III) THIS GLOBAL NOTE MAY BE DELIVERED TO THE TRUSTEE FOR CANCELLATION PURSUANT TO SECTION 2.11 OF THE INDENTURE AND (IV) THIS GLOBAL NOTE MAY BE TRANSFERRED TO A SUCCESSOR DEPOSITORY WITH THE PRIOR WRITTEN CONSENT OF THE ISSUER. UNLESS AND UNTIL IT IS EXCHANGED IN WHOLE OR IN PART FOR NOTES IN DEFINITIVE FORM, THIS NOTE MAY NOT BE TRANSFERRED EXCEPT AS A WHOLE BY THE DEPOSITORY TO A NOMINEE OF THE DEPOSITORY OR BY A NOMINEE OF THE DEPOSITORY TO THE DEPOSITORY OR ANOTHER NOMINEE OF THE DEPOSITORY OR BY THE DEPOSITORY OR ANY SUCH NOMINEE TO A SUCCESSOR DEPOSITORY OR A NOMINEE OF SUCH SUCCESSOR DEPOSITORY. UNLESS THIS CERTIFICATE IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY (“DTC”) TO THE ISSUER OR ITS AGENTS FOR REGISTRATION OF TRANSFER, EXCHANGE OR PAYMENT, AND ANY CERTIFICATE ISSUED IS REGISTERED IN THE NAME OF CEDE & CO. OR SUCH OTHER NAME AS MAY BE REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF DTC (AND ANY PAYMENT IS MADE TO CEDE & CO. OR SUCH OTHER ENTITY AS MAY BE REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL INASMUCH AS THE REGISTERED OWNER HEREOF, CEDE & CO., HAS AN INTEREST HEREIN.”

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SECTION 2.16. Designation.

The Indebtedness evidenced by the Notes and the Subsidiary Guarantees is hereby irrevocably designated as “senior indebtedness” or such other term denoting seniority for the purposes of any other existing or future Indebtedness of the Issuer or a Subsidiary Guarantor, as the case may be, which the Issuer or such Subsidiary Guarantor, as the case may be, makes subordinate to any senior (or such other term denoting seniority) indebtedness of such Person.

ARTICLE III.

REDEMPTION

SECTION 3.1. Notices to Trustee.

If the Issuer elects to redeem Notes pursuant to Paragraph 5 of the Notes, it shall notify the Trustee and the Paying Agent in writing of the Redemption Date and the principal amount of the Notes to be redeemed.

The Issuer shall give each notice provided for in this Section 3.1 at least 45 days before the Redemption Date (unless a shorter notice period shall be satisfactory to the Trustee, as evidenced in a writing signed on behalf of the Trustee), together with an Officer’s Certificate stating that such redemption shall comply with the conditions contained herein and in the Notes.

SECTION 3.2. Selection of Notes To Be Redeemed.

If less than all of the Notes are to be redeemed at any time, selection of such Notes, or portions thereof, for redemption will be made by the Trustee either in compliance with the requirements of the principal national securities exchange, if any, on which the Notes are listed or, if the Notes are not then listed or admitted to trading on a national securities exchange, in the case of Notes represented by Global Notes, by lot (or other procedures of the DTC), and, in the case of Notes represented by Definitive Notes, on a pro rata basis. No Notes of a principal amount of $2,000 or less shall be redeemed in part. If any Note is to be redeemed in part only, the notice of redemption that relates to such Note shall state the portion of the principal amount thereof to be redeemed. A new Note in a principal amount equal to the unredeemed portion thereof will be issued in the name of the Holder thereof upon cancellation of the original Note. On and after the applicable Redemption Date, interest will cease to accrue on Notes or portions thereof called for redemption as long as the Issuer shall have previously deposited with the Paying Agent for the Notes funds in satisfaction of the applicable redemption price pursuant to this Indenture.

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SECTION 3.3. Optional Redemption.

(a) Except as set forth in Sections 3.3(b) and (c), the Issuer will not be entitled to redeem the Notes at its option prior to May 1, 2013. The Notes will be redeemable, at the Issuer’s option, in whole at any time or in part from time to time, on and after May 1, 2013, at the following Redemption Prices (expressed as percentages of the principal amount thereof) if redeemed during the twelve-month period commencing on May 1 of the years set forth below, plus, in each case, unpaid accrued interest thereon to the date of redemption:


Year	Percentage
2013	111.875	%
2014 and thereafter	100.000	%

(b) At any time, or from time to time, prior to May 1, 2013, the Issuer may, at its option, use all or a portion of the Net Cash Proceeds of one or more Equity Offerings to redeem up to 35% of the aggregate principal amount of the Notes (including any Additional Notes) issued under this Indenture at a Redemption Price equal to 111.875% of the aggregate principal amount of the Notes to be redeemed, plus unpaid accrued interest thereon to the date of redemption; provided, that: (1) at least 65% of the aggregate principal amount of Notes issued under this Indenture on the Issue Date remains outstanding immediately after giving effect to any such redemption; and (2) the Issuer makes such redemption not more than 90 days after the consummation of any such Equity Offering.

(c) In addition, the Notes may be redeemed, in whole or in part, at any time prior to May 1, 2013 at the option of the Issuer at a Redemption Price equal to 100% of the principal amount of the Notes redeemed plus the Applicable Premium as of, and accrued and unpaid interest to, the applicable Redemption Date (subject to the right of holders of record on the relevant record date to receive interest due on the relevant interest payment date).

SECTION 3.4. Notice of Redemption.

In connection with a redemption pursuant to Section 3.3, at least 30 days but not more than 60 days before a Redemption Date, the Issuer shall mail or cause to be mailed a notice of redemption by first class mail to each Holder of Notes to be redeemed at its registered address, with a copy to the Trustee and any Paying Agent. At the Issuer’s request, the Trustee shall give the notice of redemption in the Issuer’s name and at the Issuer’s expense. The Issuer shall provide such notices of redemption to the Trustee at least five Business Days before the intended mailing date.

Each notice of redemption shall identify (including the CUSIP number) the Notes to be redeemed and shall state:

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(1) the Redemption Date;

(2) the Redemption Price and the amount of unpaid accrued interest, if any, to be paid;

(3) the name and address of the Paying Agent;

(4) the subparagraph of the Notes pursuant to which such redemption is being made;

(5) that Notes called for redemption must be surrendered to the Paying Agent to collect the Redemption Price plus unpaid accrued interest, if any;

(6) that, unless the Issuer defaults in making the redemption payment, interest on Notes or applicable portions thereof called for redemption ceases to accrue on and after the Redemption Date, and the only remaining right of the Holders of such Notes is to receive payment of the Redemption Price plus unpaid accrued interest as of the Redemption Date, if any, upon surrender to the Paying Agent of the Notes redeemed;

(7) if any Note is being redeemed in part, the portion of the principal amount of such Note to be redeemed and that, after the Redemption Date, and upon surrender of such Note, a new Note or Notes in the aggregate principal amount equal to the unredeemed portion thereof will be issued; and

(8) if fewer than all the Notes are to be redeemed, the identification of the particular Notes (or portion thereof) to be redeemed, as well as the aggregate principal amount of Notes to be redeemed and the aggregate principal amount of Notes to be outstanding after such partial redemption.

The Issuer will comply with the requirements of Rule 14e-1 under the Exchange Act and any other securities laws and regulations thereunder to the extent such laws and regulations are applicable in connection with the purchase of Notes.

SECTION 3.5. Effect of Notice of Redemption.

Once notice of redemption is mailed in accordance with Section 3.4, such notice of redemption shall be irrevocable and Notes called for redemption shall become due and payable on the Redemption Date and at the Redemption Price plus accrued and unpaid interest as of such date, if any. Upon surrender to the Trustee or Paying Agent, such Notes called for redemption shall be paid at the Redemption Price plus accrued and unpaid interest thereon to the Redemption Date, but installments of interest, the maturity of which is on or prior to the Redemption Date, shall be payable to Holders of record at the close of business on the rele-

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vant Record Dates referred to in the Notes. Interest shall accrue on or after the Redemption Date and shall be payable only if the Issuer defaults in payment of the Redemption Price.

SECTION 3.6. Deposit of Redemption Price.

On or before the Redemption Date and in accordance with Section 2.14, the Issuer shall deposit with the Paying Agent U.S. Legal Tender sufficient to pay the Redemption Price plus accrued and unpaid interest on all Notes to be redeemed on that date. The Paying Agent shall promptly return to the Issuer any U.S. Legal Tender so deposited which is not required for that purpose, except with respect to monies owed as obligations to the Trustee pursuant to Article VII.

Unless the Issuer fails to comply with the preceding paragraph and defaults in the payment of such Redemption Price plus unpaid accrued interest, if any, interest on the Notes to be redeemed will cease to accrue on and after the applicable Redemption Date, whether or not such Notes are presented for payment.

SECTION 3.7. Notes Redeemed in Part.

Upon surrender of a Note that is to be redeemed in part, the Trustee shall authenticate for the Holder a new Note or Notes equal in principal amount to the unredeemed portion of the Note surrendered.

ARTICLE IV.

COVENANTS

SECTION 4.1. Payment of Notes.

(a) The Issuer shall pay the principal of, premium, if any, and interest on the Notes on the dates and in the manner provided in the Notes and in this Indenture.

(b) An installment of principal of or interest on the Notes shall be considered paid on the date it is due if the Trustee or Paying Agent (other than the Issuer or any of its Affiliates) holds, prior to 11:00 a.m. New York City time on that date, U.S. Legal Tender designated for and sufficient to pay the installment in full and is not prohibited from paying such money to the Holders pursuant to the terms of this Indenture or the Notes.

(c) Notwithstanding anything to the contrary contained in this Indenture, the Issuer may, to the extent it is required to do so by law, deduct or withhold income or other similar taxes imposed by the United States of America from principal or interest payments under this Indenture.

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SECTION 4.2. Maintenance of Office or Agency.

The Issuer shall maintain the office or agency required under Section 2.3. The Issuer shall give prior written notice to the Trustee of the location, and any change in the location, of such office or agency. If at any time the Issuer shall fail to maintain any such required office or agency or shall fail to furnish the Trustee with the address thereof, such presentations, surrenders, notices and demands may be made or served at the address of the Trustee set forth in Section 11.2.

SECTION 4.3. Organizational Existence.

Except as otherwise permitted by Article V, the Issuer shall do or cause to be done, at its own cost and expense, all things necessary to preserve and keep in full force and effect its organizational existence and the organizational existence of each of its Restricted Subsidiaries in accordance with the respective organizational documents of each such Restricted Subsidiary and the material rights (charter and statutory) and franchises of the Issuer and each such Restricted Subsidiary; provided, however, that the Issuer shall not be required to preserve, with respect to itself, any material right or franchise and, with respect to any of its Restricted Subsidiaries, any such existence, material right or franchise, if the Board of Directors of the Issuer shall determine in good faith that the preservation thereof is no longer desirable in the conduct of the business of the Issuer and its Subsidiaries, taken as a whole.

SECTION 4.4. Payment of Taxes and Other Claims.

The Issuer shall pay or discharge or cause to be paid or discharged, before the same shall become delinquent, (i) all material taxes, assessments and governmental charges (including withholding taxes and any penalties, interest and additions to taxes) levied or imposed upon it or any of its Restricted Subsidiaries or properties of it or any of its Restricted Subsidiaries and (ii) all material lawful claims for labor, materials and supplies that, if unpaid, might by law become a Lien upon the property of the Issuer or any of its Restricted Subsidiaries; provided, however, that the Issuer shall not be required to pay or discharge or cause to be paid or discharged any such tax, assessment, charge or claim whose amount, applicability or validity is being contested in good faith by appropriate negotiations or proceedings properly instituted and diligently conducted for which adequate reserves, to the extent required under GAAP, have been taken.

SECTION 4.5. Maintenance of Properties and Insurance.

(a) The Issuer shall, and shall cause each of the Restricted Subsidiaries to, maintain all properties used or useful in the conduct of its business in good working order and condition (subject to ordinary wear and tear) and make all necessary repairs, renewals, replacements, additions, betterments and improvements thereto and actively conduct and carry on its business; provided, however, that nothing in this Section 4.5 shall prevent the Issuer or

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any of the Restricted Subsidiaries from discontinuing the operation and maintenance of any of its properties, if such discontinuance is (i) in the ordinary course of business pursuant to customary business terms or (ii) in the good faith judgment of the respective Boards of Directors or other governing body of the Issuer or Restricted Subsidiary, as the case may be, desirable in the conduct of their respective businesses and is not disadvantageous in any material respect to the Holders.

(b) The Issuer shall provide or cause to be provided, for itself and each of the Restricted Subsidiaries, insurance (including appropriate self-insurance) against loss or damage of the kinds that, in the good faith judgment of the Issuer, are adequate and appropriate for the conduct of the business of the Issuer and its Restricted Subsidiaries in a prudent manner, with reputable insurers or with the government of the United States of America, Canada or an agency or instrumentality thereof, in such amounts, with such deductibles, and by such methods as shall be customary, in the good faith judgment of the Issuer, for companies similarly situated in the industry.

SECTION 4.6. Compliance Certificate; Notice of Default.

(a) The Issuer and each Subsidiary Guarantor (to the extent that such Subsidiary Guarantor is so required under the TIA) shall deliver to the Trustee, within 120 days after the end of each of its fiscal years, an Officer’s Certificate (provided, however, that one of the signatories to each such Officer’s Certificate must state that he or she is the Issuer’s principal executive officer, principal financial officer or principal accounting officer), as to such Officer’s knowledge, without independent investigation, of the Issuer’s compliance with all conditions and covenants under this Indenture (without regard to any period of grace or requirement of notice provided under this Indenture) and in the event any Default under this Indenture exists, such Officers shall specify the nature of such Default. Each such Officer’s Certificate shall also notify the Trustee should the Issuer elect to change the manner in which it fixes its fiscal year end.

(b) So long as not contrary to the then current recommendations of the American Institute of Certified Public Accountants, the annual financial statements delivered pursuant to Section 4.8 shall be accompanied by a written report of the Issuer’s independent certified public accountants (who shall be a firm of established national reputation) stating (A) that their audit examination has included a review of the terms of this Indenture and the form of the Notes as they relate to accounting matters, and (B) whether, in connection with their audit examination, any Default or Event of Default has come to their attention and if such a Default or Event of Default has come to their attention, specifying the nature and period of existence thereof; provided, however, that, without any restriction as to the scope of the audit examination, such independent certified public accountants shall not be liable by reason of any failure to obtain knowledge of any such Default or Event of Default that would

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not be disclosed in the course of an audit examination conducted in accordance with generally accepted auditing standards.

(c) (i) If any Default or Event of Default has occurred and is continuing or (ii) if any Holder seeks to exercise any remedy under this Indenture with respect to a claimed Default under this Indenture or the Notes, the Issuer shall deliver to the Trustee, at its address set forth in Section 11.2 hereof, by registered or certified mail or by facsimile transmission followed by hard copy by registered or certified mail an Officer’s Certificate specifying such event, notice or other action within 30 days of the occurrence thereof.

SECTION 4.7. Compliance with Laws.

The Issuer shall comply, and shall cause each of its Restricted Subsidiaries to comply, with all applicable statutes, rules, regulations, orders and restrictions of the United States of America, all states and municipalities thereof, and of any governmental department, commission, board, regulatory authority, bureau, agency and instrumentality of the foregoing, in respect of the conduct of its respective businesses and the ownership of its respective properties, except for such noncompliances as could not singly or in the aggregate reasonably be expected to have a material adverse effect on the financial condition or results of operations of the Issuer and the Restricted Subsidiaries taken as a whole.

SECTION 4.8. Reports to Holders.

(a) Whether or not the Issuer is subject to the reporting requirements of Section 13 or Section 15(d) of the Exchange Act, to the extent not prohibited by the Exchange Act, the Issuer will make available to the Trustee and the Holders without any cost to any Holder, the annual reports and the information, documents and other reports (or copies of such portions of any of the foregoing as the SEC may by rules and regulations prescribe) that are specified in Sections 13 and 15(d) of the Exchange Act and applicable to a U.S. corporation within the time periods specified therein with respect to an accelerated filer. In the event that the Issuer is not permitted to file such reports, documents and information with the SEC pursuant to the Exchange Act, the Issuer will nevertheless make available such Exchange Act information to the Trustee and the Holders without cost to any Holder as if the Issuer were subject to the reporting requirements of Section 13 or 15(d) of the Exchange Act within the time periods specified therein with respect to a non-accelerated filer.

(b) In addition, the Issuer and the Subsidiary Guarantors have agreed that they will make available to the Holders and to prospective investors, upon the request of such Holders, the information required to be delivered pursuant to Rule 144A(d)(4) under the Securities Act so long as the Notes are not freely transferable under the Securities Act to the extent not satisfied by the foregoing. For purposes of this Section 4.8, the Issuer and the Subsidiary Guarantors will be deemed to have furnished the reports to the Trustee and the holders

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of Notes as required by this Section 4.8 if it has filed such reports with the SEC via the ▇▇▇▇▇ filing system and such reports are publicly available.

(c) Notwithstanding the foregoing, such requirements shall be deemed satisfied prior to the commencement of the Exchange Offer or the effectiveness of the Shelf Registration Statement by the filing with the SEC of the Exchange Offer Registration Statement or Shelf Registration Statement, and any amendments thereto, with such financial information that satisfies Regulation S-X of the Securities Act within the time period specified by the Registration Rights Agreement.

(d) The availability of the foregoing materials on the SEC’s website or on the Issuer’s website shall be deemed to satisfy the foregoing delivery obligations.

SECTION 4.9. Waiver of Stay, Extension or Usury Laws.

The Issuer and each of the Subsidiary Guarantors covenants (to the extent that it may lawfully do so) that it will not at any time insist upon, plead, or in any manner whatsoever claim or take the benefit or advantage of, any stay or extension law or any usury law or other law that would prohibit or forgive the Issuer from paying all or any portion of the principal of or interest on the Notes as contemplated herein, wherever enacted, now or at any time hereafter in force, or which may affect the covenants or the performance of this Indenture; and (to the extent that it may lawfully do so) the Issuer and each of the Subsidiary Guarantors hereby expressly waives all benefit or advantage of any such law, and covenants that it will not hinder, delay or impede the execution of any power herein granted to the Trustee, but will suffer and permit the execution of every such power as though no such law had been enacted.

SECTION 4.10. Limitation on Restricted Payments.

The Issuer will not, and will not permit any of its Restricted Subsidiaries, directly or indirectly, to:

(1) declare or pay any dividend or make any payment or distribution on or in respect of the Issuer’s Capital Stock (including any payment or distribution in connection with any merger or consolidation involving the Issuer or any of its Restricted Subsidiaries) except:

(a) dividends or distributions by the Issuer payable solely in Capital Stock of the Issuer (other than Disqualified Stock) or in options, warrants or other rights to purchase such Capital Stock of the Issuer; and

(b) dividends or distributions payable to the Issuer or a Restricted Subsidiary and if such Restricted Subsidiary is not a Wholly-Owned Subsidiary, to minority stockholders (or owners of an equivalent interest in the case of

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a Subsidiary that is an entity other than a corporation) so long as the Issuer or a Restricted Subsidiary receives at least its pro rata share of such dividend or distribution;

(2) purchase, redeem, defease, retire or otherwise acquire for value any Capital Stock of the Issuer or any direct or indirect parent of the Issuer held by Persons other than the Issuer or a Restricted Subsidiary (other than in exchange for Capital Stock of the Issuer (other than Disqualified Stock));

(3) purchase, repurchase, redeem, defease or otherwise acquire or retire for value, prior to scheduled maturity, scheduled repayment or scheduled sinking fund payment, any Unsecured Indebtedness (other than (x) Indebtedness permitted under clause (3) of the second paragraph of Section 4.12 or (y) the purchase, repurchase, redemption, defeasance or other acquisition or retirement of Unsecured Indebtedness purchased in anticipation of satisfying a sinking fund obligation, principal installment or final maturity, in each case due within one year of the date of purchase, repurchase, redemption, defeasance or other acquisition or retirement); or

(4) make any Restricted Investment in any Person

(each of the foregoing actions set forth in clauses (1) through (4) shall be referred to herein as a “Restricted Payment”), if at the time the Issuer or such Restricted Subsidiary makes such Restricted Payment:

(a) a Default shall have occurred and be continuing (or would result therefrom);

(b) the Issuer is not able to Incur an additional $1.00 of Indebtedness pursuant to the first paragraph of Section 4.12 after giving effect, on a pro forma basis, to such Restricted Payment; or

(c) the aggregate amount of such Restricted Payment and all other Restricted Payments declared or made subsequent to the Issue Date would exceed the sum of:

(i) 50% of Consolidated Net Income for the period (treated as one accounting period) from January 1, 2010 to the end of the most recent fiscal quarter ending prior to the date of such Restricted Payment for which internal financial statements are in existence (or, in case such Consolidated Net Income is a deficit, minus 100% of such deficit);

(ii) 100% of the aggregate Net Cash Proceeds, and the fair market value (as determined by the Issuer’s Board of Directors in good faith) of property

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or securities other than cash (including Capital Stock of Persons engaged primarily in the Oil and Gas Business or assets used in the Oil and Gas Business), in each case received by the Issuer from the issue or sale of its Capital Stock (other than Disqualified Stock) or other capital contributions subsequent to the Issue Date (other than Net Cash Proceeds received from an issuance or sale of such Capital Stock to (x) management, employees, directors or any direct or indirect parent of the Issuer, to the extent such Net Cash Proceeds have been used to make a Restricted Payment pursuant to clause (5)(a) of the next succeeding paragraph, (y) a Subsidiary of the Issuer or (z) an employee stock ownership plan, option plan or similar trust (to the extent such sale to an employee stock ownership plan, option plan or similar trust is financed by loans from or Guaranteed by the Issuer or any Restricted Subsidiary unless such loans have been repaid with cash on or prior to the date of determination));

(iii) the amount by which Indebtedness of the Issuer or its Restricted Subsidiaries is reduced on the Issuer’s balance sheet upon the conversion or exchange (other than by a Wholly-Owned Subsidiary of the Issuer) subsequent to the Issue Date of any Indebtedness of the Issuer or its Restricted Subsidiaries convertible or exchangeable for Capital Stock (other than Disqualified Stock) of the Issuer (less the amount of any cash, or the fair market value of any other property (other than such Capital Stock), distributed by the Issuer upon such conversion or exchange), together with the net proceeds, if any, received by the Issuer or any of its Restricted Subsidiaries upon such conversion or exchange;

(iv) the amount equal to the aggregate net reduction in Restricted Investments made by the Issuer or any of its Restricted Subsidiaries in any Person after the Issue Date resulting from:

(A) repurchases, repayments or redemptions of such Restricted Investments by such Person, proceeds realized upon the sale of such Restricted Investment (other than to a Subsidiary of the Issuer), repayments of loans or advances or other transfers of assets (including by way of dividend or distribution) by such Person to the Issuer or any Restricted Subsidiary;

(B) the redesignation of Unrestricted Subsidiaries as Restricted Subsidiaries (valued in each case as provided in the definition of “Investment”) not to exceed, in the case of any Unrestricted Subsidiary, the amount of Investments previously made by the Issuer or any Restricted Subsidiary in such Unrestricted Subsidiary, which amount in each case under this clause (iv) was included in the calculation of the

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amount of Restricted Payments (but without duplication of any such amount) included in calculating cumulative Consolidated Net Income); and

(C) the sale by the Issuer or any Restricted Subsidiary (other than to the Issuer or a Restricted Subsidiary) of all or a portion of the Capital Stock of an Unrestricted Subsidiary or a distribution from an Unrestricted Subsidiary or a dividend from an Unrestricted Subsidiary (whether any such distribution or dividend is made with proceeds from the issuance by such Unrestricted Subsidiary of its Capital Stock or otherwise).

Notwithstanding the foregoing, the provisions of the preceding paragraph will not prohibit:

(1) any Restricted Payment made by exchange for, or out of the proceeds of the substantially concurrent sale of, Capital Stock of the Issuer (other than Disqualified Stock and other than Capital Stock issued or sold to a Subsidiary or an employee stock ownership plan or similar trust to the extent such sale to an employee stock ownership plan or similar trust is financed by loans from or Guaranteed by the Issuer or any Restricted Subsidiary unless such loans have been repaid with cash on or prior to the date of determination) or a substantially concurrent cash capital contribution received by the Issuer from its shareholders; provided, however, that (a) such Restricted Payment will be excluded from subsequent calculations of the amount of Restricted Payments and (b) the Net Cash Proceeds from such sale of Capital Stock or capital contribution will be excluded from clause (c)(ii) of the preceding paragraph;

(2) any purchase, repurchase, redemption, defeasance or other acquisition or retirement of Unsecured Indebtedness of the Issuer or Guarantor Unsecured Obligations of any Subsidiary Guarantor made by exchange for, or out of the proceeds of the substantially concurrent sale of, Unsecured Indebtedness of the Issuer or any Subsidiary Guarantor that, in each case, is permitted to be Incurred pursuant to Section 4.12; provided, however, that such purchase, repurchase, redemption, defeasance, acquisition or retirement will be excluded from subsequent calculations of the amount of Restricted Payments;

(3) any purchase, repurchase, redemption, defeasance or other acquisition or retirement of Disqualified Stock of the Issuer or a Restricted Subsidiary made by exchange for or out of the proceeds of the substantially concurrent sale of Disqualified Stock of the Issuer or such Restricted Subsidiary, as the case may be, that, in each case, is permitted to be Incurred pursuant Section 4.12; provided, however, that such purchase, repurchase, redemption, defeasance, acquisition or retirement will be excluded from subsequent calculations of the amount of Restricted Payments;

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(4) dividends paid or distributions made within 60 days after the date of declaration if at such date of declaration such dividend or distribution would have complied with this Section 4.10; provided, however, that such dividends and distributions will be included in subsequent calculations of the amount of Restricted Payments; and provided further, however, that for purposes of clarification, this clause (4) shall not include cash payments in lieu of the issuance of fractional shares included in clause (9) below;

(5) so long as no Default has occurred and is continuing, the purchase of Capital Stock or options, warrants, equity appreciation rights or other rights to purchase or acquire Capital Stock of the Issuer held by any existing or former employees, management or directors of the Issuer or any Restricted Subsidiary of the Issuer or their assigns, estates or heirs, in each case in connection with the repurchase provisions under employee stock option or stock purchase agreements or other agreements to compensate management, employees or directors; provided that such redemptions or repurchases pursuant to this clause (5) during any calendar year will not exceed $5.0 million in the aggregate; provided further, that such amount in any calendar year may be increased by an amount not to exceed (a) the cash proceeds received by the Issuer from the sale of Capital Stock of the Issuer to then current or former members of management or directors of the Issuer and its Restricted Subsidiaries that occurs after the Issue Date (to the extent the cash proceeds from the sale of such Capital Stock have not otherwise been applied to the payment of Restricted Payments by virtue of the clause (c) of the preceding paragraph), plus (b) the cash proceeds of key man life insurance policies received by the Issuer and its Restricted Subsidiaries after the Issue Date, less (c) the amount of any Restricted Payments made pursuant to clauses (a) and (b) of this clause (5); provided further, however, that the amount of any such repurchase or redemption under this clause (5) will be excluded in subsequent calculations of the amount of Restricted Payments and the proceeds received from any such sale will be excluded from clause (c)(ii) of the preceding paragraph.

(6) repurchases, redemptions or other acquisitions or retirements for value of Capital Stock deemed to occur upon the exercise of stock options, warrants, rights to acquire Capital Stock or other convertible securities if such Capital Stock represents a portion of the exercise or exchange price thereof, and any repurchases, redemptions or other acquisitions or retirements for value of Capital Stock made in lieu of withholding taxes in connection with any exercise or exchange of warrants, options or rights to acquire Capital Stock; provided, however, that such repurchases will be excluded from subsequent calculations of the amount of Restricted Payments;

(7) the purchase, repurchase, redemption, defeasance or other acquisition or retirement for value of any Unsecured Indebtedness (i) at a purchase price not greater than 101% of the principal amount of such Unsecured Indebtedness in the

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event of a Change of Control in accordance with provisions similar to Section 4.15 or (ii) at a purchase price not greater than 100% of the principal amount thereof in accordance with provisions similar to Section 4.16; provided that, prior to or simultaneously with such purchase, repurchase, redemption, defeasance or other acquisition or retirement, the Issuer has made the Change of Control Offer or Asset Disposition Offer, as applicable, as provided in such section with respect to the Notes and has completed the repurchase or redemption of all Notes validly tendered for payment in connection with such Change of Control Offer or Asset Disposition Offer; provided, however, that such repurchases will be included in subsequent calculations of the amount of Restricted Payments pursuant to clause (c) of the preceding paragraph;

(8) cash payments in lieu of the issuance of fractional shares; provided, however, that any payment pursuant to this clause (8) shall be excluded in the calculation of the amount of Restricted Payments;

(9) the declaration and payment of scheduled or accrued dividends to holders of any class of or series of Disqualified Stock (including Cash-Pay Preferred) of the Issuer or any of its Restricted Subsidiaries issued on or after the Issue Date in accordance with Section 4.12; provided, however, that any payment pursuant to this clause (9) shall be excluded in the calculation of the amount of Restricted Payments;

(10) so long as no Default or Event of Default has occurred and is continuing, the declaration and payment of scheduled or accrued dividends to holders of any Specified Convertible Preferred to the extent such dividends are included in Consolidated Interest Expense; provided, however, that any payment pursuant to this clause (10) shall be included in the calculation of the amount of Restricted Payments pursuant to clause (c) of the preceding paragraph; and

(11) Restricted Payments in an amount not to exceed $30.0 million at any one time outstanding; provided, however, that the amount of such Restricted Payments will be included in subsequent calculations of the amount of Restricted Payments pursuant to clause (c) of the preceding paragraph.

The amount of all Restricted Payments (other than cash) shall be the fair market value on the date of such Restricted Payment of the asset(s) or securities proposed to be paid, transferred or issued by the Issuer or such Restricted Subsidiary, as the case may be, pursuant to such Restricted Payment. The fair market value of any cash Restricted Payment shall be its face amount and the fair market value of any non-cash Restricted Payment shall be determined conclusively by the Board of Directors of the Issuer acting in good faith whose resolution with respect thereto shall be delivered to the Trustee, such determination to be based upon an opinion or appraisal issued by an accounting, appraisal or investment banking firm of national standing if such fair market value is estimated in good faith by the Board of Directors of the Issuer to exceed $50.0 million. Not later than the date of making any Re-

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stricted Payment, the Issuer shall deliver to the Trustee an Officer’s Certificate stating that such Restricted Payment is permitted and setting forth the basis upon which the calculations required by Section 4.10 were computed, together with a copy of any fairness opinion or appraisal required by this Indenture.

In the event that a Restricted Payment meets the criteria of more than one of the exceptions described in (1) through (11) above or is entitled to be made pursuant to the first paragraph above, the Issuer shall, in its sole discretion, classify such Restricted Payment.

As of the Issue Date, all of the Issuer’s Subsidiaries will be Restricted Subsidiaries, except for the Infrastructure Subsidiaries. The Issuer will not permit any Unrestricted Subsidiary to become a Restricted Subsidiary except pursuant to the last sentence of the definition of “Unrestricted Subsidiary.” For purpose of designating any Restricted Subsidiary as an Unrestricted Subsidiary, all outstanding Investments by the Issuer and its Restricted Subsidiaries (except to the extent repaid) in the Subsidiary so designated will be deemed to be Restricted Payments in an amount determined as set forth in the last sentence of the definition of “Investment.” Such designation will be permitted only if a Restricted Payment in such amount would be permitted at such time, whether pursuant to the first paragraph of this Section 4.10 or under clause (11) of the second paragraph of this Section 4.10, or pursuant to the definition of “Permitted Investments,” and if such Subsidiary otherwise meets the definition of an Unrestricted Subsidiary. Unrestricted Subsidiaries will not be subject to any of the restrictive covenants set forth in this Indenture.

SECTION 4.11. Limitations on Affiliate Transactions.

The Issuer will not, and will not permit any of its Restricted Subsidiaries to, directly or indirectly, enter into, make, amend or conduct any transaction (including making a payment to, the purchase, sale, lease or exchange of any property or the rendering of any service), contract, agreement or understanding with or for the benefit of any Affiliate of the Issuer (an “Affiliate Transaction”) unless:

(1) the terms of such Affiliate Transaction are no less favorable to the Issuer or such Restricted Subsidiary, as the case may be, than those that might reasonably have been obtained in a comparable transaction at the time of such transaction in arm’s-length dealings with a Person who is not such an Affiliate of the Issuer or such Restricted Subsidiary;

(2) if such Affiliate Transaction involves an aggregate consideration in excess of $15.0 million, the terms of such transaction have been approved by a majority of the disinterested members of the Board of Directors of the Issuer (and such majority determines that such Affiliate Transaction satisfies the criteria in clause (1) above); and

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(3) if such Affiliate Transaction involves an aggregate consideration in excess of $50.0 million, the Board of Directors of the Issuer has received a written opinion from an independent investment banking, accounting or appraisal firm of nationally recognized standing that such Affiliate Transaction is fair, from a financial standpoint, to the Issuer or such Restricted Subsidiary or is not materially less favorable than those that could reasonably be expected to be obtained in a comparable transaction at such time on an arm’s-length basis from a Person that is not an Affiliate.

The preceding paragraph will not apply to:

(1) any Investment or Restricted Payment permitted by this Indenture;

(2) any issuance of securities, or other payments, awards or grants in cash, securities or otherwise pursuant to, or the funding of, employment or severance agreements and other compensation arrangements, options to purchase securities of the Issuer, restricted stock plans, long-term incentive plans, stock appreciation rights plans, participation plans or similar employee benefits plans and/or indemnity provided on behalf of directors, officers and employees approved by the Board of Directors of the Issuer;

(3) loans or advances to employees, officers or directors in the ordinary course of business of the Issuer or any of its Restricted Subsidiaries;

(4) advances to or reimbursements of employees for moving, entertainment and travel expenses, drawing accounts and similar expenditures in the ordinary course of business of the Issuer or any of its Restricted Subsidiaries;

(5) any transaction between the Issuer and a Restricted Subsidiary or between Restricted Subsidiaries and Guarantees issued by the Issuer or a Restricted Subsidiary for the benefit of the Issuer or a Restricted Subsidiary, as the case may be, not otherwise prohibited by Section 4.12;

(6) any transaction with a joint venture or similar entity which would constitute an Affiliate Transaction solely because the Issuer or a Restricted Subsidiary owns, directly or indirectly, an Equity Interest in or otherwise controls such joint venture or similar entity;

(7) the issuance or sale of any Capital Stock (other than Disqualified Stock) of the Issuer or the receipt by the Issuer of any capital contribution from its shareholders;

(8) indemnities of officers, directors and employees of the Issuer or any of its Restricted Subsidiaries required or permitted by bylaw or statutory provisions and

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any employment agreement or other employee compensation plan or arrangement entered into in the ordinary course of business by the Issuer or any of its Restricted Subsidiaries;

(9) the payment of reasonable compensation and fees paid to, and indemnity provided on behalf of, officers, directors or employees of the Issuer or any Restricted Subsidiary;

(10) the performance of obligations of the Issuer or any of its Restricted Subsidiaries under the terms of any agreement to which the Issuer or any of its Restricted Subsidiaries is a party as of or on the Issue Date, as these agreements may be amended, modified, supplemented, extended or renewed from time to time; provided, however, that any future amendment, modification, supplement, extension or renewal entered into after the Issue Date will be permitted to the extent that its terms are not materially more disadvantageous, taken as a whole, to the holders of the Notes than the terms of the agreements in effect on the Issue Date;

(11) transactions with customers, clients, suppliers, or purchasers or sellers of goods or services, in each case in the ordinary course of business and otherwise in compliance with the terms of this Indenture which are materially no less favorable to the Issuer and its Restricted Subsidiaries than those that would have been obtained in a comparable transaction with an unrelated Person, in the reasonable determination of the Board of Directors of the Issuer or the senior management thereof, or are on terms at least as favorable as might reasonably have been obtained at such time from an unaffiliated party;

(12) transactions with a Person (other than an Unrestricted Subsidiary) that is an Affiliate of the Issuer solely because the Issuer owns, directly or through a Restricted Subsidiary, an Equity Interest in such Person; and

(13) pledges of Capital Stock of Unrestricted Subsidiaries of the Issuer for the benefit of lenders to Unrestricted Subsidiaries of the Issuer.

In addition, with respect to any operating, management or other agreement entered into between the Issuer or any Restricted Subsidiary and an Infrastructure Subsidiary at the time such Infrastructure Subsidiary is an Unrestricted Subsidiary, the terms of such agreement need only comply with clauses (1) and (2) of the first paragraph of this covenant.

SECTION 4.12. Limitation on Incurrence of Indebtedness and Preferred Stock.

The Issuer will not, and will not permit any of its Restricted Subsidiaries to, directly or indirectly, Incur any Indebtedness (including Acquired Indebtedness) and the Issuer

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will not permit any of its Restricted Subsidiaries to issue Preferred Stock; provided, however, that the Issuer may Incur Indebtedness and any of the Subsidiary Guarantors may Incur Indebtedness and issue Preferred Stock if on the date thereof the Consolidated Coverage Ratio for the Issuer and its Restricted Subsidiaries is at least 2.50 to 1.00, determined on a pro forma basis (including a pro forma application of proceeds).

The first paragraph of this Section 4.12 will not prohibit the Incurrence of the following Indebtedness:

(1) Indebtedness of the Issuer Incurred pursuant to one or more Credit Facilities in an aggregate amount not to exceed the greater of (a) $150.0 million or (b) an amount equal to 10% of the Issuer’s Adjusted Consolidated Net Tangible Assets determined as of the date of the Incurrence of such Indebtedness after giving effect to the application of the proceeds therefrom, in each case outstanding at any one time;

(2) Guarantees by the Issuer or Subsidiary Guarantors of Indebtedness of the Issuer or a Subsidiary Guarantor, as the case may be, Incurred in accordance with the provisions of this Indenture; provided that in the event such Indebtedness that is being Guaranteed is a Subordinated Obligation of the Issuer or a Subsidiary Guarantor, then the related Guarantee shall be subordinated in right of payment to the Notes or the Subsidiary Guarantee to at least the same extent as the Indebtedness being Guaranteed, as the case may be;

(3) Indebtedness of the Issuer owing to and held by any Restricted Subsidiary or Indebtedness of a Restricted Subsidiary owing to and held by the Issuer or any Restricted Subsidiary; provided, however, that (i) any subsequent issuance or transfer of Capital Stock or any other event which results in any such Indebtedness being held by a Person other than the Issuer or a Restricted Subsidiary of the Issuer and (ii) any sale or other transfer of any such Indebtedness to a Person other than the Issuer or a Restricted Subsidiary of the Issuer shall be deemed, in each case, to constitute an Incurrence of such Indebtedness by the Issuer or such Subsidiary, as the case may be;

(4) Indebtedness represented by (a) the Notes issued on the Issue Date, and the related exchange notes issued in a registered exchange offer (or shelf registration) pursuant to the Registration Rights Agreement, and all Subsidiary Guarantees, (b) any Indebtedness (other than the Indebtedness described in clauses (1), (2) and 4(a)) outstanding on the Issue Date and (c) any Refinancing Indebtedness Incurred in respect of any Indebtedness described in this clause (4) or clause (5) or Incurred pursuant to the first paragraph of this Section 4.12;

(5) Indebtedness of a Person that becomes a Restricted Subsidiary or is acquired by the Issuer or a Restricted Subsidiary or merged into the Issuer or a Restricted Subsidiary in accordance with this Indenture and outstanding on the date on

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which such Person became a Restricted Subsidiary or was acquired by or was merged into the Issuer or such Restricted Subsidiary (other than Indebtedness Incurred (a) to provide all or any portion of the funds utilized to consummate the transaction or series of related transactions pursuant to which such Person became a Restricted Subsidiary or was otherwise acquired by or was merged into the Issuer or a Restricted Subsidiary or (b) otherwise in connection with, or in contemplation of, such acquisition); provided, however, that at the time such Person becomes a Restricted Subsidiary or is acquired by or was merged into the Issuer or a Restricted Subsidiary, the Issuer would have been able to Incur $1.00 of additional Indebtedness pursuant to the first paragraph of this Section 4.12 after giving effect to the Incurrence of such Indebtedness pursuant to this clause (5);

(6) the Incurrence by the Issuer or any Restricted Subsidiary of Indebtedness represented by Capitalized Lease Obligations, Synthetic Lease Obligations, mortgage financings or purchase money obligations, in each case Incurred for the purpose of financing all or any part of the purchase price or cost of construction or improvements or carrying costs of property used in the business of the Issuer or such Restricted Subsidiary, and Refinancing Indebtedness Incurred to Refinance any Indebtedness Incurred pursuant to this clause (6) in an aggregate outstanding principal amount which, when taken together with the principal amount of all other Indebtedness incurred pursuant to this clause (6) and then outstanding, will not exceed $60.0 million at any time outstanding;

(7) Permitted Acquisition Indebtedness;

(8) Indebtedness Incurred in respect of (a) workers’ compensation claims, payment obligations in connection with health or other types of social security benefits, unemployment or other insurance or self-insurance obligations, reclamation, statutory obligations, bankers’ acceptances, bid, appeal, reimbursement, performance, surety and similar bonds and completion guarantees provided by the Issuer or a Restricted Subsidiary in the ordinary course of business and any Guarantees or Letters of Credit functioning as or supporting any of the foregoing bonds or obligations and (b) obligations represented by Letters of Credit for the account of the Issuer or a Restricted Subsidiary in order to provide security for workers’ compensation claims or completion or performance guarantees or equipment leases, or other similar obligations in the ordinary course of business or consistent with past practice (in the case of clauses (a) and (b) other than for an obligation for money borrowed);

(9) Indebtedness, including Refinancing Indebtedness, Incurred by a Foreign Subsidiary in an aggregate amount not to exceed 10% of such Foreign Subsidiary’s Adjusted Consolidated Net Tangible Assets at any time outstanding;

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(10) Capital Stock (other than Disqualified Stock) of the Issuer or of any of the Subsidiary Guarantors;

(11) Cash-Pay Preferred issued by the Issuer; provided, however, that at the time of such issuance, the Issuer would have been able to Incur $1.00 of additional Indebtedness pursuant to the first paragraph of this covenant after giving effect to the Incurrence of such Cash Pay Preferred pursuant to this clause (11);

(12) Indebtedness Incurred after the Issue Date by a wholly-owned Foreign Subsidiary in an aggregate amount not to exceed $250.0 million at any time outstanding as vendor financing related to the construction of ATP Octabuoy drilling and production platform and an unsecured Guarantee thereof by the Issuer; provided, however, that such Foreign Subsidiary ceasing to be a wholly-owned Subsidiary (other than directors’ qualifying shares) shall be deemed an Incurrence by the Issuer of such Guarantee that is not permitted by this clause (12); and

(13) in addition to the items referred to in clauses (1) through (12) above, Indebtedness of the Issuer and its Subsidiary Guarantors in an aggregate outstanding principal amount which, when taken together with the principal amount of all other Indebtedness Incurred pursuant to this clause (13) and then outstanding, will not at any time exceed the greater of $50 million or 1.25% of the Issuer’s Adjusted Consolidated Net Tangible Assets, determined as of the date of Incurrence of such Indebtedness after giving effect to such Incurrence and the application of the proceeds therefrom.

For purposes of determining compliance with, and the outstanding principal amount of any particular Indebtedness Incurred pursuant to and in compliance with, this Section 4.12:

(1) in the event an item of that Indebtedness meets the criteria of more than one of the types of Indebtedness described in the first and second paragraphs of this Section 4.12, the Issuer, in its sole discretion, will classify such item of Indebtedness on the date of Incurrence and, subject to clause (2) below may later classify, reclassify or redivide all or a portion of such item of Indebtedness, in any manner that complies with this Section 4.12;

(2) all Indebtedness outstanding on the date of this Indenture under the Senior Secured Credit Agreement shall be deemed Incurred on the Issue Date under clause (1) of the second paragraph of this Section 4.12;

(3) Guarantees of, or obligations in respect of Letters of Credit supporting, Indebtedness which is otherwise included in the determination of a particular amount of Indebtedness shall not be included;

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(4) if obligations in respect of Letters of Credit are Incurred pursuant to a Credit Facility and are being treated as Incurred pursuant to clause (1) of the second paragraph above and the Letters of Credit relate to other Indebtedness, then such other Indebtedness shall not be included;

(5) the principal amount of any Disqualified Stock of the Issuer or a Restricted Subsidiary, or Preferred Stock of a Restricted Subsidiary that is not a Subsidiary Guarantor, will be equal to the greater of the maximum mandatory redemption or repurchase price (not including, in either case, any redemption or repurchase premium) or the liquidation preference thereof;

(6) Indebtedness permitted by this Section 4.12 need not be permitted solely by reference to one provision permitting such Indebtedness but may be permitted in part by one such provision and in part by one or more other provisions of this Section 4.12 permitting such Indebtedness; and

(7) the amount of Indebtedness issued at a price that is less than the principal amount thereof will be equal to the amount of the liability in respect thereof determined in accordance with GAAP.

Accrual of interest, accrual of dividends, the amortization of debt discount or the accretion of accreted value, the payment of interest in the form of additional Indebtedness, the payment of dividends in the form of additional shares of Preferred Stock or Disqualified Stock and unrealized losses or charges in respect of Hedging Obligations (including those resulting from the application of Statement of Financial Accounting Standard No. 133) will not be deemed to be an Incurrence of Indebtedness for purposes of this Section 4.12. The amount of any Indebtedness outstanding as of any date shall be (i) the accreted value thereof in the case of any Indebtedness issued with original issue discount and (ii) the principal amount or liquidation preference thereof, together with any interest thereon that is more than 30 days past due, in the case of any other Indebtedness.

If at any time an Unrestricted Subsidiary becomes a Restricted Subsidiary, any Indebtedness of such Subsidiary shall be deemed to be Incurred by a Restricted Subsidiary as of such date (and, if such Indebtedness is not permitted to be Incurred as of such date under this Section 4.12, the Issuer shall be in Default of this Section 4.12).

For purposes of determining compliance with any U.S. dollar-denominated restriction on the Incurrence of Indebtedness, the U.S. dollar-equivalent principal amount of Indebtedness denominated in a foreign currency shall be calculated based on the relevant currency exchange rate in effect on the date such Indebtedness was Incurred, in the case of term Indebtedness, or first committed, in the case of revolving credit Indebtedness; provided that if such Indebtedness is Incurred to refinance other Indebtedness denominated in a foreign currency, and such refinancing would cause the applicable U.S. dollar-denominated restriction to

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be exceeded if calculated at the relevant currency exchange rate in effect on the date of such refinancing, such U.S. dollar-denominated restriction shall be deemed not to have been exceeded so long as the principal amount of such refinancing Indebtedness does not exceed the principal amount of such Indebtedness being refinanced. Notwithstanding any other provision of this Section 4.12, the maximum amount of Indebtedness that the Issuer may Incur pursuant to this Section 4.12 shall not be deemed to be exceeded solely as a result of fluctuations in the exchange rate of currencies. The principal amount of any Indebtedness Incurred to refinance other Indebtedness, if Incurred in a different currency from the Indebtedness being refinanced, shall be calculated based on the currency exchange rate applicable to the currencies in which such Refinancing Indebtedness is denominated that is in effect on the date of such refinancing.

This Indenture will not treat (1) unsecured Indebtedness as subordinated or junior to secured Indebtedness merely because it is unsecured or (2) senior Indebtedness as subordinated or junior to any other senior Indebtedness merely because it has a junior priority with respect to the same collateral.

SECTION 4.13. Limitation on Restrictions on Distributions from Restricted Subsidiaries.

The Issuer will not, and will not permit any Restricted Subsidiary to, create or otherwise cause or permit to exist or become effective any consensual encumbrance or consensual restriction on the ability of any Restricted Subsidiary to:

(1) pay dividends or make any other distributions on its Capital Stock or pay any Indebtedness or other obligations owed to the Issuer or any Restricted Subsidiary (it being understood that the priority of any Preferred Stock in receiving dividends or liquidating distributions prior to dividends or liquidating distributions being paid on Common Stock shall not be deemed a restriction on the ability to make distributions on Capital Stock);

(2) make any loans or advances to the Issuer or any Restricted Subsidiary (it being understood that the subordination of loans or advances made to the Issuer or any Restricted Subsidiary to other Indebtedness Incurred by the Issuer or any Restricted Subsidiary shall not be deemed a restriction on the ability to make loans or advances); or

(3) sell, lease or transfer any of its property or assets to the Issuer or any Restricted Subsidiary.

The preceding provisions will not prohibit:

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(i) any encumbrance or restriction pursuant to or by reason of an agreement in effect at or entered into on the Issue Date, including, without limitation, this Indenture, the Security Documents and the Intercreditor Agreement in effect on such date but excluding the Senior Secured Credit Agreement;

(ii) any encumbrance or restriction with respect to a Person pursuant to or by reason of an agreement relating to any Capital Stock or Indebtedness Incurred by a Person on or before the date on which such Person was acquired by the Issuer or another Restricted Subsidiary (other than Capital Stock or Indebtedness Incurred as consideration in, or to provide all or any portion of the funds utilized to consummate, the transaction or series of related transactions pursuant to which such Person was acquired by the Issuer or a Restricted Subsidiary or in contemplation of the transaction) and outstanding on such date; provided, that any such encumbrance or restriction shall not extend to any assets or property of the Issuer or any other Restricted Subsidiary other than the assets and property so acquired;

(iii) encumbrances and restrictions contained in contracts entered into in the ordinary course of business, not relating to any Indebtedness, and that do not, individually or in the aggregate, detract from the value of, or from the ability of the Issuer and the Restricted Subsidiaries to realize the value of, property or assets of the Issuer or any Restricted Subsidiary in any manner material to the Issuer or any Restricted Subsidiary;

(iv) any encumbrance or restriction with respect to an Unrestricted Subsidiary pursuant to or by reason of an agreement that the Unrestricted Subsidiary is a party to entered into before the date on which such Unrestricted Subsidiary became a Restricted Subsidiary; provided, that such agreement was not entered into in anticipation of the Unrestricted Subsidiary becoming a Restricted Subsidiary and any such encumbrance or restriction shall not extend to any assets or property of the Issuer or any other Restricted Subsidiary other than the assets and property so acquired;

(v) with respect to any Foreign Subsidiary, any encumbrance or restriction contained in the terms of any Indebtedness or any agreement pursuant to which such Indebtedness was Incurred if either (1) the encumbrance or restriction applies only in the event of a payment default or a default with respect to a financial covenant in such Indebtedness or agreement or (2) the Issuer determines that any such encumbrance or restriction will not materially affect the Issuer’s ability to make principal or interest payments on the Notes, as determined in good faith by the Board of Directors of the Issuer, whose determination shall be conclusive;

(vi) any encumbrance or restriction with respect to a Restricted Subsidiary pursuant to an agreement effecting a refunding, replacement or refinancing of Indebtedness Incurred pursuant to an agreement referred to in clauses (i) through (v)

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or clause (xii) of this paragraph or this clause (vi) or contained in any amendment, restatement, modification, renewal, supplemental, refunding, replacement or refinancing of an agreement referred to in clauses (i) through (v) or clause (xii) of this paragraph or this clause (vi); provided that the encumbrances and restrictions with respect to such Restricted Subsidiary contained in any such agreement taken as a whole are no less favorable in any material respect to the holders of the Notes than the encumbrances and restrictions contained in the agreements governing the Indebtedness being refunded, replaced or refinanced;

(vii) in the case of clause (3) of the first paragraph of this Section 4.13, any encumbrance or restriction:

(a) that restricts in a customary manner the subletting, assignment or transfer of any property or asset that is subject to a lease (including leases governing leasehold interests or farm-in agreements or farm-out agreements relating to leasehold interests in Oil and Gas Properties), license or similar contract, or the assignment or transfer of any such lease (including leases governing leasehold interests or farm-in agreements or farm-out agreements relating to leasehold interests in Oil and Gas Properties), license (including, without limitation, licenses of intellectual property) or other contract;

(b) contained in mortgages, pledges or other security agreements permitted under this Indenture securing Indebtedness of the Issuer or a Restricted Subsidiary to the extent such encumbrances or restrictions restrict the transfer of the property subject to such mortgages, pledges or other security agreements;

(d) pursuant to customary provisions restricting dispositions of real property interests set forth in any reciprocal easement agreements of the Issuer or any Restricted Subsidiary;

(e) restrictions on cash or other deposits imposed by customers under contracts entered into in the ordinary course of business; or

(f) provisions with respect to the disposition or distribution of assets or property in operating agreements, joint venture agreements, development agreements, area of mutual interest agreements and other agreements that are customary in the Oil and Gas Business and entered into in the ordinary course of business;

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(viii) (a) purchase money obligations for property acquired in the ordinary course of business and (b) Capitalized Lease Obligations permitted under this Indenture, in each case, that impose encumbrances or restrictions of the nature described in clause (3) of the first paragraph of this Section 4.13 on the property so acquired;

(ix) any encumbrance or restriction with respect to a Restricted Subsidiary (or any of its property or assets) imposed pursuant to an agreement entered into for the direct or indirect sale or disposition of all or a portion of the Capital Stock or assets of such Restricted Subsidiary (or the property or assets that are subject to such restriction) pending the closing of such sale or disposition;

(x) any customary encumbrances or restrictions imposed pursuant to any agreement of the type described in the definition of “Permitted Business Investment”;

(xi) encumbrances or restrictions arising or existing by reason of applicable law or any applicable rule, regulation or order;

(xii) other Indebtedness of the Issuer or any of its Restricted Subsidiaries permitted to be Incurred pursuant to an agreement entered into subsequent to the Issue Date in accordance with Section 4.12; provided that the provisions relating to such encumbrance or restriction contained in such Indebtedness are not materially less favorable to the Issuer taken as a whole, as determined by the Board of Directors of the Issuer in good faith, than the provisions contained in the Senior Secured Credit Agreement and in this Indenture as in effect on the Issue Date;

(xiii) the issuance of Preferred Stock by a Restricted Subsidiary or the payment of dividends thereon in accordance with the terms thereof; provided that issuance of such Preferred Stock is permitted pursuant to Section 4.12 and the terms of such Preferred Stock do not expressly restrict the ability of a Restricted Subsidiary to pay dividends or make any other distributions on its Capital Stock (other than requirements to pay dividends or liquidation preferences on such Preferred Stock prior to paying any dividends or making any other distributions on such other Capital Stock);

(xiv) supermajority voting requirements existing under corporate charters, bylaws, stockholders agreements and similar documents and agreements;

(xv) restrictions on cash or other deposits or net worth imposed by customers under contracts entered into in the ordinary course of business; and

(xvi) the Senior Secured Credit Agreement as in effect as of the Issue Date, and any amendments, modifications, restatements, renewals, increases, supple-

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ments, refundings, replacements or refinancings thereof; provided that such amendments, modifications, restatements, renewals, increases, supplements, refundings, replacements or refinancings are no more restrictive with respect to such dividend and other payment restrictions than those contained in the Senior Secured Credit Agreement as in effect on the Issue Date.

SECTION 4.14. Reserved.

SECTION 4.15. Change of Control.

If a Change of Control occurs, unless the Issuer has previously or concurrently exercised its right to redeem all of the Notes pursuant to Section 3.3, each Holder will have the right to require the Issuer to repurchase all or any part of such Holder’s Notes at a purchase price in cash equal to 101% of the principal amount of the Notes plus accrued and unpaid interest, if any, to but not including the date of purchase (subject to the right of holders of record on the relevant record date to receive interest due on the relevant interest payment date).

Within 30 days following any Change of Control (or at the Issuer’s option, after a definitive agreement is in place for a Change of Control, prior to the occurrence of such Change of Control), unless the Issuer has previously or concurrently exercised its right to redeem all of the Notes pursuant to Section 3.3, the Issuer will mail a notice (the “Change of Control Offer”) to each Holder, with a copy to the Trustee, stating:

(1) that a Change of Control has occurred and that such Holder has the right to require the Issuer to purchase such Holder’s Notes at a purchase price in cash equal to 101% of the principal amount of such Notes plus accrued and unpaid interest, if any, to but not including the date of purchase (subject to the right of holders of record on a record date to receive interest on the relevant interest payment date) (the “Change of Control Payment”);

(2) the repurchase date (which shall be no earlier than 30 days nor later than 60 days from the date such notice is mailed) (the “Change of Control Payment Date”);

(3) that any Note not properly tendered will remain outstanding and continue to accrue interest;

(4) that unless the Issuer defaults in the payment of the Change of Control Payment, all Notes accepted for payment pursuant to the Change of Control Offer will cease to accrue interest on the Change of Control Payment Date;

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(5) that Holders electing to have any Notes purchased pursuant to a Change of Control Offer will be required to surrender such Notes, with the form entitled “Option of Holder to Elect Purchase” on the reverse of such Notes completed, to the paying agent specified in the notice at the address specified in the notice prior to the close of business on the third Business Day preceding the Change of Control Payment Date; and

(6) the procedures determined by the Issuer, consistent with this Indenture, that a Holder must follow in order to have its Notes repurchased.

On the Change of Control Payment Date, the Issuer will, to the extent lawful:

(1) accept for payment all Notes properly tendered pursuant to the Change of Control Offer;

(2) deposit with the paying agent an amount equal to the Change of Control Payment in respect of all Notes properly tendered; and

(3) deliver or cause to be delivered to the Trustee the Notes so accepted together with an Officer’s Certificate stating the aggregate principal amount of Notes or portions of Notes being purchased by the Issuer.

The paying agent will promptly mail to each Holder of Notes properly tendered the Change of Control Payment for such Notes.

In the event that Holders of not less than 95% of the aggregate principal amount of the outstanding Notes accept a Change of Control Offer and the Issuer purchases all of the Notes held by such Holders, the Issuer will have the right, on not less than 30, nor more than 60, days’ prior notice, given not more than 30 days following the purchase pursuant to the Change of Control Offer described above, to redeem all of the Notes that remain outstanding following such purchase at a purchase price equal to the Change of Control payment price plus, to the extent not included in the Change of Control payment price, unpaid accrued interest and premium, if any, on the Notes that remain outstanding, to, but not including, the date of redemption (subject to the right of Holders on the relevant record date to receive interest due on the relevant interest payment date).

If the Change of Control Payment Date is on or after an interest record date and on or before the related interest payment date, any accrued and unpaid interest will be paid to the Person in whose name a Note is registered at the close of business on such record date, and no further interest will be payable to holders who tender pursuant to the Change of Control Offer.

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The Change of Control provisions described above will be applicable whether or not any other provisions of this Indenture are applicable. Except as described above with respect to a Change of Control, this Indenture does not contain provisions that permit the Holders to require that the Issuer repurchase or redeem the Notes in the event of a takeover, recapitalization or similar transaction.

The Issuer will not be required to make a Change of Control Offer upon a Change of Control if a third party makes the Change of Control Offer in the manner, at the times and otherwise in compliance with the requirements set forth in this Indenture applicable to a Change of Control Offer made by the Issuer and purchases all Notes validly tendered under such Change of Control Offer.

A Change of Control Offer may be made in advance of a Change of Control, and conditioned upon the occurrence of a Change of Control, if a definitive agreement is in place for the Change of Control at the time of making the Change of Control Offer.

The Issuer will comply, to the extent applicable, with the requirements of Rule 14e-1 of the Exchange Act and any other securities laws or regulations in connection with the repurchase of Notes as a result of a Change of Control. To the extent that the provisions of any securities laws or regulations conflict with provisions of this Indenture, or compliance with the Change of Control provisions of this Indenture would constitute a violation of any such laws or regulations, the Issuer will comply with the applicable securities laws and regulations and will not be deemed to have breached its obligations described in this Indenture by virtue of its compliance with such securities laws or regulations.

SECTION 4.16. Limitation on Sales of Assets and Subsidiary Stock.

The Issuer will not, and will not permit any of its Restricted Subsidiaries to, make any Asset Disposition unless:

(1) the Issuer or such Restricted Subsidiary, as the case may be, receives consideration at the time of such Asset Disposition at least equal to the fair market value (such fair market value to be determined on the date of contractually agreeing to such Asset Disposition), as determined in good faith by the Board of Directors (including as to the value of all non-cash consideration), of the shares and assets subject to such Asset Disposition;

(2) at least 75% of the consideration received by the Issuer or such Restricted Subsidiary, as the case may be, from such Asset Disposition is in the form of cash or Cash Equivalents or Additional Assets, or any combination thereof; and

(3) except as provided in the next paragraph, an amount equal to 100% of the Net Available Cash from such Asset Disposition is applied, within one year from

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the later of the date of such Asset Disposition or the receipt of such Net Available Cash, by the Issuer or such Restricted Subsidiary, as the case may be:

(a) to the extent the Issuer or any Restricted Subsidiary, as the case may be, elects (or is required by the terms of any Indebtedness), to prepay, repay, redeem or purchase First-Lien Obligations of the Issuer under the Senior Secured Credit Agreement, any other Indebtedness of the Issuer or a Subsidiary Guarantor that is secured by a Lien permitted to be Incurred under this Indenture or Indebtedness (other than Disqualified Stock) of any Wholly-Owned Subsidiary that is not a Subsidiary Guarantor;

(b) to invest in Additional Assets; provided that to the extent that the assets disposed of in such Asset Disposition were Collateral, such Additional Assets which would constitute Collateral are pledged as Collateral under the Security Documents with the Lien on such Collateral securing the Notes being of the same priority with respect to the Notes as the Lien on the assets disposed of; or

provided that pending the final application of any such Net Available Cash in accordance with this Section 4.16, the Issuer and its Restricted Subsidiaries may temporarily reduce Indebtedness or otherwise invest such Net Available Cash in any manner not prohibited by this Indenture.

Any Net Available Cash from Asset Dispositions that is not applied or invested as provided in the preceding paragraph will be deemed to constitute “Excess Proceeds.” Not later than the day following the date that is one year from the later of the date of such Asset Disposition or the receipt of such Net Available Cash, if the aggregate amount of Excess Proceeds exceeds $20.0 million, the Issuer will be required to make an offer (“Asset Disposition Offer”) to (i) in the case of Net Available Cash from dispositions of assets constituting Collateral, all Holders of Notes and all holders of Other Second-Lien Obligations if required by the terms thereof, and (ii) in the case of other Net Available Cash, all Holders of Notes and all holders of other Pari Passu Indebtedness outstanding with similar provisions requiring the Issuer to make an offer to purchase such Pari Passu Indebtedness with the proceeds from any Asset Disposition (“Pari Passu Notes”) in each case to purchase the maximum principal amount of Notes and any such Other Second-Lien Obligations or Pari Passu Notes, as applicable, to which the Asset Disposition Offer applies that may be purchased out of the Excess Proceeds, at an offer price in cash in an amount equal to 100% of the principal amount (or, in the event such Pari Passu Indebtedness of the Issuer was issued with significant original issue discount, 100% of the accreted value thereof) of the Notes and Other Second-Lien Obligations or Pari Passu Notes, as applicable, plus accrued and unpaid interest (or in respect of such

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Other Second-Lien Obligations or Pari Passu Indebtedness, as applicable, such lesser price, if any, as may be provided for by the terms of such Indebtedness) to but not including the date of purchase (subject to the right of holders of record on the relevant record date to receive interest due on the relevant interest payment date), in accordance with the procedures set forth in this Indenture or the agreements governing the Other Second-Lien Obligations or Pari Passu Notes, as applicable, in each case in minimum principal amount of $2,000 and integral multiples of $1,000 in excess of $2,000. If the aggregate principal amount of Notes surrendered by holders thereof and Other Second-Lien Obligations or other Pari Passu Notes, as applicable, surrendered by holders or lenders, collectively, exceeds the amount of Excess Proceeds, the Trustee shall select the Notes to be purchased on a pro rata basis on the basis of the aggregate principal amount of tendered Notes and Other Second-Lien Obligations or Pari Passu Notes, as applicable. To the extent that the aggregate amount of Notes and Other Second-Lien Obligations or Pari Passu Notes, as applicable, so validly tendered and not properly withdrawn pursuant to an Asset Disposition Offer is less than the Excess Proceeds, the Issuer may use any remaining Excess Proceeds for general corporate purposes, subject to the other covenants contained in this Indenture. Upon completion of such Asset Disposition Offer, the amount of Excess Proceeds shall be reset at zero.

The Asset Disposition Offer will remain open for a period of 20 Business Days following its commencement, except to the extent that a longer period is required by applicable law (the “Asset Disposition Offer Period”). No later than five Business Days after the termination of the Asset Disposition Offer Period (the “Asset Disposition Purchase Date”), the Issuer will purchase the principal amount of Notes and Other Second-Lien Obligations or Pari Passu Notes, as applicable, required to be purchased pursuant to this Section 4.16 (the “Asset Disposition Offer Amount”) or, if less than the Asset Disposition Offer Amount has been so validly tendered, all Notes and Other Second-Lien Obligations or Pari Passu Notes, as applicable, validly tendered in response to the Asset Disposition Offer.

If the Asset Disposition Purchase Date is on or after an interest record date and on or before the related interest payment date, any accrued and unpaid interest will be paid to the Person in whose name a Note is registered at the close of business on such record date, and no further interest will be payable to holders who tender Notes pursuant to the Asset Disposition Offer.

On or before the Asset Disposition Purchase Date, the Issuer will, to the extent lawful, accept for payment, on a pro rata basis to the extent necessary, the Asset Disposition Offer Amount of Notes and Pari Passu Notes or portions of Notes and Pari Passu Notes so validly tendered pursuant to the Asset Disposition Offer, or if less than the Asset Disposition Offer Amount has been validly tendered, all Notes and Pari Passu Notes so validly tendered. The Issuer will deliver to the Trustee an Officer’s Certificate stating that such Notes or portions thereof were accepted for payment by the Issuer in accordance with the terms of this Section 4.16 and, in addition, the Issuer will deliver all certificates and notes required, if any,

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by the agreements governing the Pari Passu Notes. The Issuer or the paying agent, as the case may be, will promptly (but in any case not later than five Business Days after the termination of the Asset Disposition Offer Period) mail or deliver to each tendering Holder or holder or lender of Pari Passu Notes, as the case may be, an amount equal to the purchase price of the Notes or Pari Passu Notes so validly tendered by such holder or lender, as the case may be, and accepted by the Issuer for purchase, and the Issuer will promptly issue a new Note, and the Trustee, upon delivery of an Authentication Order in accordance with Section 2.2 hereof, will authenticate and mail or deliver such new Note to such Holder, in a principal amount equal to any unpurchased portion of the Note surrendered. In addition, the Issuer will take any and all other actions required by the agreements governing the Pari Passu Notes. Any Note not so accepted will be promptly mailed or delivered by the Issuer to the Holder thereof. The Issuer will publicly announce the results of the Asset Disposition Offer on the Asset Disposition Purchase Date.

The Issuer will comply, to the extent applicable, with the requirements of Rule 14e-1 of the Exchange Act and any other securities laws or regulations in connection with the repurchase of Notes pursuant to this Indenture. To the extent that the provisions of any securities laws or regulations conflict with provisions of this Section 4.16, the Issuer will comply with the applicable securities laws and regulations and will not be deemed to have breached its obligations under this Indenture by virtue of its compliance with such securities laws or regulations.

For the purposes of clause (2) of the first paragraph of this Section 4.16, the following will be deemed to be cash or Cash Equivalents:

(1) the assumption by the transferee of Indebtedness (other than Unsecured Indebtedness or Disqualified Stock) of the Issuer or Indebtedness of a Restricted Subsidiary (other than Unsecured Indebtedness or Disqualified Stock of any Restricted Subsidiary that is a Subsidiary Guarantor) and the release of the Issuer or such Restricted Subsidiary from all liability on such Indebtedness in connection with such Asset Disposition (or in lieu of such a release, the agreement of the acquirer or its parent company to indemnify and hold the Issuer or such Restricted Subsidiary harmless from and against any loss, liability or cost in respect of such assumed Indebtedness; provided, however, that such indemnity is (i) from an indemnifying party (or its long term debt securities) with an Investment Grade Rating (with no indication of a negative outlook or credit watch with negative implications, in any case, that contemplates such indemnifying party (or its long term debt securities) failing to have an Investment Grade Rating or (ii) accompanied by the posting of a letter of credit (issued by a commercial bank that has an Investment Grade Rating) in favor of the Issuer or such Restricted Subsidiary for the full amount of the liability and for so long as the liability remains outstanding, in which case the Issuer will, without further action, be deemed

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to have applied such deemed cash to Indebtedness in accordance with clause (3)(a) of the first paragraph of this Section 4.16; and

(2) securities, notes or other obligations received by the Issuer or any Restricted Subsidiary from the transferee that are converted by the Issuer or such Restricted Subsidiary into cash within 90 days after receipt thereof.

Notwithstanding the foregoing, the 75% limitation referred to in clause (2) of the first paragraph of this Section 4.16 shall be deemed satisfied with respect to any Asset Disposition in which the cash or Cash Equivalents portion of the consideration received therefrom, determined in accordance with the foregoing provision on an after-tax basis, is equal to or greater than what the after-tax proceeds would have been had such Asset Disposition complied with the aforementioned 75% limitation.

The requirement of clause (3)(b) of the first paragraph of this Section 4.16 above shall be deemed to be satisfied if an agreement (including a lease, whether a capital lease or an operating lease) committing to make the acquisitions or expenditures referred to therein is entered into by the Issuer or its Restricted Subsidiary within the specified time period and such Net Available Cash is subsequently applied in accordance with such agreement within six months following such agreement.

SECTION 4.17. Reserved.

SECTION 4.18. Limitation on Liens.

The Issuer shall not, and shall not permit any of its Restricted Subsidiaries to, directly or indirectly, create, Incur or suffer to exist (i) any Lien on any asset or property that is not Collateral of the Issuer or such Restricted Subsidiary securing Indebtedness unless the Notes are equally and ratably secured with (or on a senior basis to, in the case of obligations subordinated in right of payment to the Notes) the obligations so secured or (ii) any Lien on any asset or property that is Collateral.

The preceding paragraph shall not prohibit Permitted Liens nor shall it require the Issuer or any Restricted Subsidiary of the Issuer to secure the Notes if the Lien consists of a Permitted Lien. Any Lien which is granted to secure the Notes or such Subsidiary Guarantee under clause (i) of the preceding paragraph (unless also granted pursuant to clause (ii) of the preceding paragraph) shall be automatically released and discharged at the same time as the release of the Lien that gave rise to the obligation to secure the Notes or such Subsidiary Guarantee under such clause (i).

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SECTION 4.19. Limitation on Lines of Business.

The Issuer will not, and will not permit any Restricted Subsidiary to, engage in any business other than the Oil and Gas Business, except to the extent as would not be material to the Issuer and its Restricted Subsidiaries taken as a whole.

SECTION 4.20. Additional Subsidiary Guarantees.

The Issuer shall cause each Restricted Subsidiary, other than a Foreign Subsidiary created or acquired by the Issuer or one or more of its Restricted Subsidiaries, to execute and deliver a Subsidiary Guarantee; provided that any Restricted Subsidiary that constitutes an Immaterial Subsidiary need not become a Subsidiary Guarantor until such time as it ceases to be an Immaterial Subsidiary. If required to execute and deliver a Subsidiary Guarantee pursuant to this paragraph, such transferee or acquired or other Restricted Subsidiary shall:

(1) execute and deliver to the Trustee a supplemental indenture in form reasonably satisfactory to the Trustee pursuant to which such Restricted Subsidiary shall unconditionally guarantee all of the Issuer’s obligations under the Notes and this Indenture on the terms set forth in this Indenture;

(2) deliver to the Trustee an Opinion of Counsel that such supplemental indenture has been duly authorized, executed and delivered by such Restricted Subsidiary and constitutes a legal, valid, binding and enforceable obligation of such Restricted Subsidiary. Thereafter, such Restricted Subsidiary shall be a Subsidiary Guarantor for all purposes of this Indenture; and

(3) become a party to the Intercreditor Agreement and the Security Documents and shall take such actions as are reasonably necessary or advisable to grant the Collateral Agent, for the benefit of the Holders of the Notes and the Trustee, a perfected Second-Priority Lien on any Collateral held by such Restricted Subsidiary, subject to Permitted Liens.

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ARTICLE V.

SUCCESSOR CORPORATION

SECTION 5.1. Merger, Consolidation and Sale of All or Substantially All Assets.

The Issuer will not consolidate with or merge with or into or wind up into (whether or not the Issuer is the surviving corporation), or convey, transfer or lease all or substantially all its assets (determined on a consolidated basis) in one or more related transactions to, any Person, unless:

(1) either (a) the Issuer shall be the surviving corporation or (b) the resulting, surviving or transferee Person (the “Successor Issuer”) (x) will be a corporation, partnership, trust or limited liability company organized and existing under the laws of the United States of America, any State of the United States or the District of Columbia and the Successor Issuer (if not the Issuer) and (y) will expressly assume, by supplemental indenture, executed and delivered to the Trustee, in form reasonably satisfactory to the Trustee, all the obligations of the Issuer under the Notes, this Indenture, the Registration Rights Agreement, the Intercreditor Agreement and the Security Documents, and all such obligations shall remain in full force and effect and the Successor Issuer shall cause such amendments, supplements or other instruments to be executed, filed and recorded in such jurisdictions as may be required by applicable law to preserve and protect the Lien on the Collateral pledged by or transferred to such Person, together with the financing statements and comparable documents as may be required to perfect any security interests in such Collateral which may be perfected by the filing of a financing statement or a similar document under the UCC or other similar statute or regulation of the relevant states or jurisdictions, in each case in a form reasonably satisfactory to the Trustee;

(2) immediately after giving effect to such transaction and the assumption contemplated by clause (1)(b)(y) above (including, without limitation, giving effect to any Indebtedness incurred or anticipated to be incurred and any Lien granted in connection with or in respect of the transaction), no Default shall have occurred and be continuing;

(3) immediately after giving effect to such transaction and the assumption contemplated by clause (1)(b)(y) above (including, without limitation, giving effect to any Indebtedness incurred or anticipated to be incurred in connection with or in respect of such transaction) and the application of any net proceeds therefrom, (A) the Issuer or the Successor Issuer would, on the date of such transaction, after giving pro forma effect thereto and to any related financing transactions as if the same had oc-

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curred at the beginning of the applicable four quarter period, be able to Incur at least an additional $1.00 of Indebtedness pursuant to the first paragraph of Section 4.12 or (B) the Consolidated Coverage Ratio of the Issuer or the Successor Issuer, as the case may be, is equal to or greater than the Consolidated Coverage Ratio of the Issuer immediately before such transaction;

(4) each Subsidiary Guarantor (unless it is the other party to the transactions above, in which case clause (1) shall apply) shall have by supplemental indenture confirmed that its Subsidiary Guarantee shall apply to such Person’s obligations in respect of this Indenture and the Notes and its obligations under the Registration Rights Agreement, the Intercreditor Agreement and the Security Documents (if applicable) shall continue to be in effect; and

(5) the Issuer or the Successor Issuer, as the case may be, shall have delivered to the Trustee an Officer’s Certificate and an Opinion of Counsel, each stating that such consolidation, merger or transfer and, if a supplemental indenture and additional Security Documents are required in connection with such transaction, such supplemental indenture and Security Documents comply with the applicable provisions of this Indenture and Security Documents and that all conditions precedent in this Indenture relating to such transaction have been satisfied; provided, however, that such counsel may rely, as to matters of fact, on a certificate or certificates of officers of the Issuer.

For purposes of this Section 5.1, the sale, lease, conveyance, assignment, transfer, or other disposition of all or substantially all of the properties and assets of one or more Restricted Subsidiaries of the Issuer, which properties and assets, if held by the Issuer instead of such Restricted Subsidiaries, would constitute all or substantially all of the properties and assets of the Issuer on a consolidated basis, shall be deemed to be the transfer of all or substantially all of the properties and assets of the Issuer.

The Successor Issuer will succeed to, and be substituted for, and may exercise every right and power of, the Issuer under this Indenture, the Registration Rights Agreement, the Intercreditor Agreement and the Security Documents as if such Successor Issuer had been named in such; and its predecessor Issuer, except in the case of a lease of all or substantially all its assets, will be released from the obligation to pay the principal of and interest on the Notes.

Notwithstanding the preceding clause (3), (x) any Restricted Subsidiary may consolidate with, merge into or transfer all or part of its properties and assets to the Issuer and the Issuer may consolidate with, merge into or transfer all or part of its properties and assets to a Wholly-Owned Subsidiary and (y) the Issuer may merge with an Affiliate incorporated solely for the purpose of reincorporating the Issuer in another jurisdiction; provided that, in the case of a Restricted Subsidiary that consolidates with, merges into or transfers all or part

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of its properties and assets to the Issuer, the Issuer will not be required to comply with the preceding clause (5).

In addition, the Issuer will not permit any Subsidiary Guarantor to consolidate with or merge with or into, and will not permit the conveyance, transfer or lease of substantially all of the assets of any Subsidiary Guarantor to, any Person (other than the Issuer or another Subsidiary Guarantor) unless:

(1) (a) the resulting, surviving or transferee Person will be a corporation, partnership, trust or limited liability company organized and existing under the laws of the United States of America, any State of the United States or the District of Columbia and such Person (if not such Subsidiary Guarantor) will expressly assume, by supplemental indenture and (if required) additional Security Documents, executed and delivered to the Trustee, all the obligations of such Subsidiary Guarantor under its Subsidiary Guarantee and (b) immediately after giving effect to such transaction (and treating any Indebtedness that becomes an obligation of the resulting, surviving or transferee Person or any Restricted Subsidiary as a result of such transaction as having been Incurred by such Person or such Restricted Subsidiary at the time of such transaction), no Default shall have occurred and be continuing; or

(2) the transaction is made in compliance with Section 4.16 and Section 12.4.

ARTICLE VI.

REMEDIES

SECTION 6.1. Events of Default.

An “Event of Default” means any of the following events:

(1) default in any payment of interest on any Note when due, continued for 30 days;

(2) default in the payment of principal of or premium, if any, on any Note when due at its Stated Maturity, upon optional redemption, upon required repurchase, upon declaration of acceleration or otherwise;

(3) failure by the Issuer or any Subsidiary Guarantor to comply with its obligations under Section 5.1;

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(4) failure by the Issuer to comply for 30 days after notice as provided below with any of its obligations under Sections 4.8, 4.10, 4.11, 4.12, 4.13, 4.15, 4.16, 4.18, 4.19 or 4.20 above (in each case, other than a failure to purchase Notes which will constitute an Event of Default under clause (2) above and other than a failure to comply with Section 5.1 which is covered by clause (3));

(5) failure by the Issuer to comply for 60 days after notice as provided below with its other agreements contained in this Indenture;

(6) default under any mortgage, indenture or instrument under which there may be issued or by which there may be secured or evidenced any Indebtedness for money borrowed by the Issuer or any of its Restricted Subsidiaries (or the payment of which is guaranteed by the Issuer or any of its Restricted Subsidiaries), other than Indebtedness owed to the Issuer or a Restricted Subsidiary, whether such Indebtedness or guarantee now exists, or is created after the date of this Indenture, which default:

(a) is caused by a failure to pay principal of, or interest or premium, if any, on such Indebtedness prior to the expiration of the grace period provided in such Indebtedness (and any extensions of any grace period) (“payment default”); or

(b) results in the acceleration of such Indebtedness prior to its express maturity;

and, in each case, the principal amount of any such Indebtedness, together with the principal amount of any other such Indebtedness under which there has been a payment default or the maturity of which has been so accelerated, aggregates $25.0 million or more;

(7) certain events of bankruptcy, insolvency or reorganization of the Issuer or a Significant Subsidiary or group of Restricted Subsidiaries that, taken together (as of the latest audited consolidated financial statements for the Issuer and its Restricted Subsidiaries), would constitute a Significant Subsidiary;

(8) failure by the Issuer or any Significant Subsidiary or group of Restricted Subsidiaries that, taken together (as of the latest audited consolidated financial statements for the Issuer and its Restricted Subsidiaries), would constitute a Significant Subsidiary to pay final judgments aggregating in excess of $25.0 million (to the extent not covered by insurance by a reputable and creditworthy insurer as to which the insurer has not disclaimed coverage), which judgments are not paid or discharged, and there shall be any period of 60 consecutive days following entry of such final judgment or decree during which a stay of enforcement of such final judgment or decree, by reason of pending appeal or otherwise, shall not be in effect;

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(9) any Subsidiary Guarantee of a Significant Subsidiary or group of Restricted Subsidiaries that, taken together (as of the latest audited consolidated financial statements for the Issuer and its Restricted Subsidiaries) would constitute a Significant Subsidiary, ceases to be in full force and effect (except as contemplated by the terms of this Indenture) or is declared null and void in a judicial proceeding or any Subsidiary Guarantor that is a Significant Subsidiary or group of Subsidiary Guarantors that, taken together (as of the latest audited consolidated financial statements of the Issuer and its Restricted Subsidiaries) would constitute a Significant Subsidiary denies or disaffirms its obligations under this Indenture or its Subsidiary Guarantee; or

(10) so long as the Security Documents have not been otherwise terminated in accordance with their terms and the Collateral as a whole has not been released from the Lien of the Security Documents securing the Notes in accordance with the terms thereof, with respect to Collateral having a Fair Market Value in excess of $100.0 million, individually or in the aggregate, (a) the security interest under any Security Document, at any time, ceases to be in full force and effect for any reason other than in accordance with the terms of this Indenture, the Security Documents and the Intercreditor Agreement, (b) repudiation or disaffirmation of the Issuer or any Subsidiary Guarantor of its respective obligations under the Security Documents or (c) the determination in a judicial proceeding that the Security Documents are unenforceable or invalid against the Issuer or any Subsidiary Guarantor for any reason.

However, a default under clauses (3), (4) and (5) of this Section 6.1 will not constitute an Event of Default until the Trustee or the holders of 25% in principal amount of the outstanding Notes notify the Issuer in writing and, in the case of a notice given by the holders, the Trustee specifying the default (and demanding that such default be remedied) and the Issuer does not cure such default within the time specified in clauses (4) and (5) of this paragraph after receipt of such notice.

SECTION 6.2. Acceleration.

If an Event of Default (other than an Event of Default described in clause (7) of Section 6.1) occurs and is continuing, the Trustee by notice to the Issuer, or the Holders of at least 25% in principal amount of the outstanding Notes by notice to the Issuer and the Trustee, may, and the Trustee at the request of such Holders shall, declare the principal of, premium, if any, accrued and unpaid interest, if any, on all the Notes to be due and payable. If an Event of Default described in clause (7) of Section 6.1 occurs and is continuing, the principal of, premium, if any, accrued and unpaid interest on all the Notes will become and be immediately due and payable without any declaration or other act on the part of the Trustee or any Holders. The Holders of a majority in principal amount of the outstanding Notes may waive all past defaults (except with respect to nonpayment of principal, premium or interest) and rescind any such acceleration with respect to the Notes and its consequences if (1) rescission

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would not conflict with any judgment or decree of a court of competent jurisdiction and (2) all existing Events of Default, other than the nonpayment of the principal of, premium, if any, and interest on the Notes that have become due solely by such declaration of acceleration, have been cured or waived.

Notwithstanding the foregoing, (a) if an Event of Default specified in clause (6) of Section 6.1 shall have occurred and be continuing, such Event of Default and any consequential acceleration (to the extent not in violation of any applicable law) shall be automatically rescinded if (i) the Indebtedness that is the subject of such Event of Default has been repaid or (ii) if the default relating to such Indebtedness is waived or cured and if such Indebtedness has been accelerated, then the holders thereof have rescinded their declaration of acceleration in respect of such Indebtedness and (b) if an Event of Default specified in clause (10) of Section 6.1 shall have occurred and be continuing, such Event of Default and any consequential acceleration (to the extent not in violation of any applicable law) shall be automatically rescinded if the Lien on such Collateral (with appropriate priority) has been reinstated within 90 days.

SECTION 6.3. Other Remedies.

If an Event of Default occurs and is continuing, the Trustee may pursue any available remedy by proceeding at law or in equity to collect the payment of the principal of, premium or interest on the Notes or to enforce the performance of any provision of the Notes or this Indenture.

All rights of action and claims under this Indenture or the Notes may be enforced by the Trustee even if it does not possess any of the Notes or does not produce any of them in the proceeding. A delay or omission by the Trustee or any Holder in exercising any right or remedy accruing upon an Event of Default shall not impair the right or remedy or constitute a waiver of or acquiescence in the Event of Default. No remedy is exclusive of any other remedy. All available remedies are cumulative to the extent permitted by law.

SECTION 6.4. Waiver of Past Defaults.

At any time prior to the declaration of acceleration of the Notes, the Holders of not less than a majority in aggregate principal amount of the Notes then outstanding by notice to the Trustee may, on behalf of the Holders of all the Notes, waive any existing Default or Event of Default and its consequences under this Indenture, except a Default or Event of Default specified in clauses (1) or (2) of Section 6.1 or in respect of any provision hereof which cannot be modified or amended without the consent of the Holder so affected pursuant to Section 9.2. When a Default or Event of Default is so waived, it shall be deemed cured and shall cease to exist. This Section 6.4 shall be in lieu of § 316(a)(1)(B) of the TIA and such § 316(a)(1)(B) of the TIA is hereby expressly excluded from this Indenture and the Notes, as permitted by the TIA.

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SECTION 6.5. Control by Majority.

Holders of the Notes may not enforce this Indenture or the Notes except as provided in this Article VI and under the TIA. The Holders of not less than a majority in aggregate principal amount of the outstanding Notes shall have the right to direct the time, method and place of conducting any proceeding for any remedy available to the Trustee, or exercising any trust or power conferred on the Trustee, provided, however, that the Trustee may refuse to follow any direction (a) that conflicts with any rule of law or this Indenture, or the Intercreditor Agreement, (b) that the Trustee reasonably determines may be unduly prejudicial to the rights of any other Holder, or (c) that may expose the Trustee to personal liability for which indemnity provided to the Trustee against such liability shall be deemed inadequate by the Trustee; provided, further, however, that the Trustee may take any other action deemed proper by the Trustee that is not inconsistent with such direction or this Indenture. This Section 6.5 shall be in lieu of § 316(a)(1)(A) of the TIA, and such § 316(a)(1)(A) of the TIA is hereby expressly excluded from this Indenture and the Notes, as permitted by the TIA.

SECTION 6.6. Limitation on Suits.

Subject to the provisions of this Indenture relating to the duties of the Trustee, if an Event of Default occurs and is continuing, the Trustee will be under no obligation to exercise any of the rights or powers under this Indenture at the request or direction of any of the holders unless such Holders have offered to the Trustee indemnity satisfactory to the Trustee or security against any loss, liability or expense. Except to enforce the right to receive payment of principal, premium, if any, or interest when due, no Holder may pursue any remedy with respect to this Indenture or the Notes unless:

(1) such Holder has previously given the Trustee notice that an Event of Default is continuing;

(2) Holders of at least 25% in principal amount of the outstanding Notes have requested the Trustee to pursue the remedy;

(3) such Holder has offered the Trustee security or indemnity satisfactory to the Trustee against any loss, liability or expense;

(4) the Trustee has not complied with such request within 60 days after the receipt of the request and the offer of security or indemnity; and

(5) the Holders of a majority in principal amount of the outstanding Notes have not waived such Event of Default or otherwise given the Trustee a direction that, in the opinion of the Trustee, is inconsistent with such request within such 60-day period.

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A Holder may not use this Indenture to prejudice the rights of any other Holders or to obtain priority or preference over such other Holders.

SECTION 6.7. Right of Holders To Receive Payment.

Notwithstanding any other provision in this Indenture, the right of any Holder of a Note to receive payment of the principal of, premium and interest on such Note, on or after the respective due dates expressed or provided for in such Note, or to bring suit for the enforcement of any such payment on or after the respective due dates, is absolute and unconditional and shall not be impaired or affected without the consent of the Holder.

SECTION 6.8. Collection Suit by Trustee.

If an Event of Default specified in clause (1) or (2) of Section 6.1 occurs and is continuing, the Trustee may recover judgment in its own name and as trustee of an express trust against the Issuer, or any other obligor on the Notes for the whole amount of the principal of, premium, if any, and accrued interest remaining unpaid, together with interest on overdue principal and, to the extent that payment of such interest is lawful, interest on overdue installments of interest, in each case at the rate per annum provided for by the Notes and such further amount as shall be sufficient to cover the costs and expenses of collection, including the reasonable compensation, expenses, disbursements and advances of the Trustee, its agents and counsel.

SECTION 6.9. Trustee May File Proofs of Claim.

The Trustee may file such proofs of claim and other papers or documents as may be necessary or advisable in order to have the claims of the Trustee (including any claim for the reasonable compensation, expenses, disbursements and advances of the Trustee, its agents, counsel, accountants and experts) and the Holders allowed in any judicial proceedings relative to the Issuer or Restricted Subsidiaries (or any other obligor upon the Notes), their creditors or their property and shall be entitled and empowered to collect and receive any monies or other property payable or deliverable on any such claims and to distribute the same, and any Custodian in any such judicial proceedings is hereby authorized by each Holder to make such payments to the Trustee and, in the event that the Trustee shall consent to the making of such payments directly to the Holders, to pay to the Trustee any amount due to it for the reasonable compensation, expenses, disbursements and advances of the Trustee, its agent and counsel, and any other amounts due the Trustee under Section 7.7. Nothing herein contained shall be deemed to authorize the Trustee to authorize or consent to or accept or adopt on behalf of any Holder any plan of reorganization, arrangement, adjustment or composition affecting the Notes or the rights of any Holder thereof, or to authorize the Trustee to vote in respect of the claim of any Holder in any such proceeding.

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SECTION 6.10. Priorities.

If the Trustee collects any money pursuant to this Article VI it shall pay out such money in the following order:

First: to the Trustee for amounts due under Section 7.7;

Second: to Holders for interest accrued on the Notes, ratably, without preference or priority of any kind, according to the amounts due and payable on the Notes for interest;

Third: to Holders for the principal amounts (including any premium) owing under the Notes, ratably, without preference or priority of any kind, according to the amounts due and payable on the Notes for the principal (including any premium); and

Fourth: the balance, if any, to the Issuer.

The Trustee, upon prior written notice to the Issuer, may fix a record date and payment date for any payment to Holders pursuant to this Section 6.10.

SECTION 6.11. Undertaking for Costs.

In any suit for the enforcement of any right or remedy under this Indenture or in any suit against the Trustee for any action taken or omitted by it as Trustee, a court may in its discretion require the filing by any party litigant in the suit of an undertaking to pay the costs of the suit, and the court in its discretion may assess reasonable costs, including reasonable attorneys’ fees, against any party litigant in the suit, having due regard to the merits and good faith of the claims or defenses made by the party litigant. This Section 6.11 does not apply to any suit by the Trustee, any suit by a Holder pursuant to Section 6.7, or a suit by a Holder or Holders of more than 10% in aggregate principal amount of the outstanding Notes.

SECTION 6.12. Restoration of Rights and Remedies.

If the Trustee or any Holder has instituted any proceeding to enforce any right or remedy under this Indenture or any Note and such proceeding has been discontinued or abandoned for any reason, or has been determined adversely to the Trustee or to such Holder, then and in every such case the Issuer, the Trustee and the Holders shall, subject to any determination in such proceeding, be restored severally and respectively to their former positions under this Indenture, and thereafter all rights and remedies of the Trustee and the Holders shall continue as though no such proceeding had been instituted.

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ARTICLE VII.

TRUSTEE

SECTION 7.1. Duties of Trustee.

(a) If an Event of Default has occurred, of which the Trustee is deemed to have notice, and is continuing, the Trustee may exercise such of the rights and powers vested in it by this Indenture and shall use the same degree of care and skill in its exercise thereof as a prudent person would exercise or use under the circumstances in the conduct of his own affairs.

(b) Except during the continuance of an Event of Default:

(1) The Trustee need perform only those duties as are specifically set forth in this Indenture and no covenants or obligations shall be implied in this Indenture that are adverse to the Trustee. The permissive right of the Trustee to do things enumerated in this Indenture shall not be construed as a duty.

(2) In the absence of bad faith on its part, the Trustee may conclusively rely, as to the truth of the statements and the correctness of the opinions expressed therein, upon certificates or opinions furnished to the Trustee and conforming to the requirements of this Indenture. However, in the case of any such certificates or opinions that by any provision hereof are specifically required to be furnished to the Trustee, the Trustee shall examine the certificates and opinions to determine whether or not they conform to the requirements of this Indenture.

(c) Notwithstanding anything to the contrary herein contained, the Trustee may not be relieved from liability for its own negligent action, its own negligent failure to act, or its own willful misconduct, except that:

(1) This paragraph does not limit the effect of paragraph (b) of this Section 7.1.

(2) The Trustee shall not be liable for any error of judgment made in good faith by a Trust Officer, unless it is conclusively determined by a court of competent jurisdiction that the Trustee was negligent in ascertaining the pertinent facts.

(3) The Trustee shall not be liable with respect to any action it takes or omits to take in good faith in accordance with a direction received by it pursuant to Section 6.2, 6.4 or 6.5.

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(d) No provision of this Indenture shall require the Trustee to expend or risk its own funds or otherwise incur any financial liability in the performance of any of its duties under this Indenture or in the exercise of any of its rights or powers.

(e) Every provision of this Indenture that in any way relates to the Trustee is subject to paragraphs (a), (b), (c) and (d) of this Section 7.1 and Section 7.2.

(f) The Trustee shall not be liable for interest on any money or assets received by it except as the Trustee may agree in writing with the Issuer. Assets held in trust by the Trustee need not be segregated from other assets except to the extent required by law.

SECTION 7.2. Rights of Trustee.

Subject to Section 7.1:

(a) The Trustee may conclusively rely and shall be fully protected in acting or refraining from acting upon any document believed by it to be genuine and to have been signed or presented by the proper Person or Persons or to have been prepared and furnished pursuant to any of the provisions of this Indenture; and the Trustee shall be under no duty to make any investigation as to any statement contained in any such instance, but may accept the same conclusive evidence of the truth and accuracy of such statement or the correctness of such opinions. The Trustee need not investigate any fact or matter stated in the document.

(b) Before the Trustee acts or refrains from acting, it may consult with counsel of its selection and may require an Officer’s Certificate or an Opinion of Counsel, which shall conform to Sections 11.4 and 11.5. The Trustee shall not be liable for any action it takes or omits to take in good faith in reliance on such advice or such Officer’s Certificate or Opinion of Counsel.

(c) The Trustee may act through attorneys, agents, custodians or nominees and shall not be responsible for the misconduct or negligence of any attorney, agent, custodian or nominee appointed with due care.

(d) The Trustee shall not be liable for any action that it takes or omits to take in good faith which it believes to be authorized or within its rights or powers conferred upon it by this Indenture.

(e) The Trustee shall not be bound to make any investigation into the facts or matters stated in any resolution, certificate, statement, instrument, opinion, notice, request, direction, consent, order, bond, debenture, or other paper or document, but the Trustee, in its discretion, may make such further inquiry or investigation into such facts or matters as it may see fit, and, if the Trustee shall determine to make such fur-

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ther inquiry or investigation, it shall be entitled, upon reasonable notice to the Issuer, to examine the books, records, and premises of the Issuer, personally or by agent or attorney and to consult with the officers and representatives of the Issuer, including the Issuer’s accountants and attorneys.

(f) The Trustee shall be under no obligation to exercise any of the rights or powers vested in it by this Indenture at the request, order or direction of any of the Holders pursuant to the provisions of this Indenture, unless such Holders shall have offered to the Trustee security or indemnity satisfactory to the Trustee against the costs, expenses and liabilities which may be incurred by it in compliance with such request, order or direction.

(g) The Trustee shall not be required to give any bond or surety in respect of the performance of its powers and duties under this Indenture.

(h) Delivery of reports, information and documents to the Trustee under Section 4.8 is for informational purposes only and the Trustee’s receipt of the foregoing shall not constitute constructive notice of any information contained therein or determinable from information contained therein, including the Issuer’s compliance with any of its covenants under this Indenture (as to which the Trustee is entitled to rely exclusively on Officer’s Certificates).

(i) Other than a consent revoked in accordance with Section 9.4, any action taken, or omitted to be taken, by the Trustee in good faith pursuant to this Indenture upon the request or authority or consent of any person who, at the time of making such request or giving such authority or consent, is a Holder shall be conclusive and binding upon every subsequent Holder of a Note or portion of a Note that evidences the same debt as the requesting or consenting Holder’s Note.

(j) In no event shall the Trustee be responsible or liable for special, indirect, or consequential loss or damage of any kind whatsoever (including, but not limited to, loss of profit) irrespective of whether the Trustee has been advised of the likelihood of such loss or damage and regardless of the form of action.

SECTION 7.3. Individual Rights of Trustee.

The Trustee in its individual or any other capacity may become the owner or pledgee of Notes and may otherwise deal with the Issuer, any of its respective Subsidiaries, or its respective Affiliates with the same rights it would have if it were not Trustee. Any Agent may do the same with like rights. However, the Trustee must comply with Sections 7.10 and 7.11.

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SECTION 7.4. Trustee’s Disclaimer.

The Trustee makes no representation as to the validity or adequacy of this Indenture or the Notes, and it shall not be accountable for the Issuer’s use of the proceeds from the Notes, and it shall not be responsible for any statement of the Issuer in this Indenture or the Notes other than the Trustee’s certificate of authentication.

Under no circumstances shall the Trustee be liable in its individual capacity for the obligations evidenced by the Notes. In accepting the trust hereby created, the Trustee acts solely as Trustee for the Holders and not in its individual capacity and all persons, including without limitation the Holders and the Issuer having any claim against the Trustee arising from this Indenture shall look only to the funds and accounts held by the Trustee hereunder for payment except as otherwise provided herein.

SECTION 7.5. Notice of Default.

The Trustee may withhold the provision of any notice of a Default or Event of Default known to the Trustee if and so long as its Board of Directors, the executive committee of its Board of Directors or a committee of its directors and/or Trust Officers in good faith determines that withholding the notice is in the interest of the Holders. The foregoing sentence of this Section 7.5 shall be in lieu of the proviso to § 315(b) of the TIA and such proviso to § 315(b) of the TIA is hereby expressly excluded from this Indenture and the Notes, as permitted by the TIA.

SECTION 7.6. Reports by Trustee to Holders.

Within 60 days after May 15 of each year beginning with 2010 and for so long as Notes remain outstanding, the Trustee shall, to the extent that any of the events described in TIA § 313(a) occurred within the previous twelve months, but not otherwise, mail to each Holder a brief report dated as of such date that complies with TIA § 313(a). The Trustee also shall comply with TIA §§ 313(b), (c) and (d).

A copy of each report at the time of its mailing to Holders shall be mailed to the Issuer.

The Issuer shall promptly notify the Trustee if the Notes become listed on any stock exchange and the Trustee shall comply with TIA § 313(d).

SECTION 7.7. Compensation and Indemnity.

The Issuer shall pay to the Trustee from time to time such compensation for its services as has been agreed to in writing signed by the Issuer and the Trustee. The Trustee’s compensation shall not be limited by any law on compensation of a trustee of an express trust.

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The Issuer shall reimburse the Trustee upon request for all reasonable out-of-pocket expenses incurred or made by it in connection with the performance of its duties under this Indenture. Such expenses shall include the reasonable fees and expenses of the Trustee’s agents, counsel, accountants and experts.

The Issuer and the Subsidiary Guarantors shall indemnify each of the Trustee (or any predecessor Trustee) and its agents, employees, stockholders, Affiliates and directors and officers for, and hold them each harmless against, any and all loss, liability, damage, claim or expense (including reasonable fees and expenses of counsel), including taxes (other than taxes based on the income of the Trustee) incurred by them except for such actions to the extent caused by any negligence, bad faith or willful misconduct on their part, arising out of or in connection with the acceptance or administration of this Indenture including the costs and expenses of defending themselves against any claim or liability in connection with the exercise or performance of any of their rights, powers or duties under this Indenture. The Trustee shall notify the Issuer promptly of any claim asserted against the Trustee for which it may seek indemnity. At the Trustee’s sole discretion, the Issuer or such Subsidiary Guarantor shall defend the claim and the Trustee shall cooperate and may participate in the defense; provided, however, that any settlement of a claim shall be approved in writing by the Trustee if such settlement would result in an admission of liability by the Trustee or if such settlement would not be accompanied by a full release of the Trustee for all liability arising out of the events giving rise to such claim. Alternatively, the Trustee may at its option have separate counsel of its own choosing and the Issuer shall pay the reasonable fees and expenses of such counsel.

To secure the Issuer’s and the Subsidiary Guarantors’ payment obligations in this Section 7.7, the Trustee shall have a Lien prior to the Notes on all assets or money held or collected by the Trustee, in its capacity as Trustee, except assets or money held in trust to pay principal of or premium, if any, or interest on particular Notes.

When the Trustee incurs expenses or renders services after an Event of Default specified in clause (7) of Section 6.1 occurs, such expenses and the compensation for such services are intended to constitute expenses of administration under any Bankruptcy Law.

The provisions of this Section 7.7 shall survive the termination of this Indenture or the earlier resignation or removal of the Trustee.

SECTION 7.8. Replacement of Trustee.

The Trustee may resign at any time by so notifying the Issuer. The Holders of a majority in principal amount of the outstanding Notes may remove the Trustee and appoint a successor Trustee with the Issuer’s consent, by so notifying the Issuer and the Trustee. The Issuer may remove the Trustee if:

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(1) the Trustee fails to comply with Section 7.10;

(2) the Trustee is adjudged bankrupt or insolvent;

(3) a receiver or other public officer takes charge of the Trustee or its property; or

(4) the Trustee becomes incapable of acting.

If the Trustee resigns or is removed or if a vacancy exists in the office of Trustee for any reason, the Issuer shall notify each Holder of such event and shall promptly appoint a successor Trustee. Within one year after the successor Trustee takes office, the Holders of a majority in aggregate principal amount of the outstanding Notes may appoint a successor Trustee to replace the successor Trustee appointed by the Issuer.

A successor Trustee shall deliver a written acceptance of its appointment to the retiring Trustee and to the Issuer. Immediately after that, the retiring Trustee shall transfer all property held by it as Trustee to the successor Trustee, subject to the lien provided in Section 7.7, the resignation or removal of the retiring Trustee shall become effective, and the successor Trustee shall have all the rights, powers and duties of the Trustee under this Indenture. The Issuer shall mail notice of such successor Trustee’s appointment to each Holder.

If a successor Trustee does not take office within 45 days after the retiring Trustee resigns or is removed, the retiring Trustee, the Issuer or the Holders of at least 10% in aggregate principal amount of the outstanding Notes may petition any court of competent jurisdiction for the appointment of a successor Trustee.

If the Trustee fails to comply with Section 7.10, any Holder may petition any court of competent jurisdiction for the removal of the Trustee and the appointment of a successor Trustee.

Notwithstanding any resignation or replacement of the Trustee pursuant to this Section 7.8, the Issuer’s obligations under Section 7.7 shall continue for the benefit of the retiring Trustee.

SECTION 7.9. Successor Trustee by Merger, Etc.

If the Trustee consolidates with, merges or converts into, or transfers all or substantially all of its corporate trust business to, another corporation, the resulting, surviving or transferee corporation without any further act shall, if such resulting, surviving or transferee corporation is otherwise eligible under this Indenture, be the successor Trustee; provided, however, that such corporation shall be otherwise qualified and eligible under this Article VII.

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SECTION 7.10. Eligibility; Disqualification.

This Indenture shall always have a Trustee who satisfies the requirement of TIA §§ 310(a)(1), (2) and (5). The Trustee (or, in the case of a Trustee that is a corporation included in a bank holding company system, the related bank holding company) shall have a combined capital and surplus of at least $150 million as set forth in its most recent published annual report of condition. In addition, if the Trustee is a corporation included in a bank holding company system, the Trustee, independently of such bank holding company, shall meet the capital requirements of TIA § 310(a)(2). The Trustee shall comply with TIA § 310(b); provided, however, that there shall be excluded from the operation of TIA § 310(b)(1) any indenture or indentures under which other securities, or certificates of interest or participation in other securities, of the Issuer are outstanding, if the requirements for such exclusion set forth in TIA § 310(b)(1) are met. The provisions of TIA § 310 shall apply to the Issuer, as obligor of the Notes.

SECTION 7.11. Preferential Collection of Claims Against the Issuer.

The Trustee shall comply with TIA § 311(a), excluding any creditor relationship listed in TIA § 311(b). A Trustee who has resigned or been removed shall be subject to TIA § 311(a) to the extent indicated therein. The provisions of TIA § 311 shall apply to the Issuer, as obligor on the Notes.

SECTION 7.12. Force Majeure.

In no event shall the Trustee be liable for any failure or delay in the performance of its obligations under this Indenture because of circumstances beyond the Trustee’s control, including, but not limited to, acts of God, flood, war (whether declared or undeclared), terrorism, fire, riot, embargo, government action, including any laws, ordinances, regulations, governmental action or the like which delay, restrict or prohibit the providing of the services contemplated by this Indenture.

SECTION 7.13. Defaults and Events of Default.

The Trustee shall not be required to take notice or be deemed to have notice of any Default, except failure of the Issuer to cause to be made any of the payments required to be made to the Trustee, unless the Trustee shall be specifically notified by a writing of such Default by the Issuer or by the Holders of at least 25% in aggregate principal amount of all Notes then outstanding delivered to the Corporate Trust Office of the Trustee and such notice references the Notes and the Indenture and, in the absence of such notice so delivered, the Trustee may conclusively assume no Default exists.

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ARTICLE VIII.

DISCHARGE OF INDENTURE; DEFEASANCE

SECTION 8.1. Termination of Issuer’s Obligations.

This Indenture will be discharged and will cease to be of further effect (except as to surviving rights of registration of transfer or exchange of the Notes, as expressly provided for in this Indenture) as to all outstanding Notes when (a) either (i) all the Notes, theretofore authenticated (except lost, stolen or destroyed Notes that have been replaced or paid and Notes for whose payment money has theretofore been deposited in trust or segregated and held in trust by the Issuer and thereafter repaid to the Issuer or discharged from such trust) have been delivered to the Trustee for cancellation or (ii) all Notes not theretofore delivered to the Trustee for cancellation have become due and payable or will become due and payable within one year by reason of the giving of a notice of redemption or otherwise and the Issuer or any Subsidiary Guarantor has irrevocably deposited or caused to be irrevocably deposited with the Trustee as trust funds in trust solely for such purpose, cash in U.S. dollars, U.S. Government Obligations, or a combination thereof, in such amounts as will be sufficient without consideration of any reinvestment of interest, to pay and discharge the entire Indebtedness on the Notes not theretofore delivered to the Trustee for cancellation, for principal of, premium, if any, and interest on the Notes to the date of maturity or redemption together with irrevocable instructions from the Issuer directing the Trustee to apply such funds to the payment thereof at maturity or redemption, as the case may be, and if in either case the Issuer pays all other sums payable under this Indenture by the Issuer, then this Indenture, the Subsidiary Guarantees, the Security Documents and the Intercreditor Agreement shall, except for certain obligations, including those respecting the defeasance trust and obligations to register the transfer or exchange of the Notes, to replace mutilated, destroyed, lost or stolen Notes and to maintain a Registrar and Paying Agent in respect of the Notes, cease to be of further effect and all Liens under the Security Documents will be released; (b) the Issuer has paid all other sums payable under this Indenture by the Issuer; and (c) the Issuer has delivered to the Trustee an Officer’s Certificate and an Opinion of Counsel stating that all conditions precedent under this Indenture relating to the satisfaction and discharge of this Indenture have been complied with; provided, however, that such counsel may rely, as to matters of fact, on a certificate or certificates of officers of the Issuer.

The Issuer may, at its option and at any time, elect to have its obligations and the corresponding obligations of the Subsidiary Guarantors discharged with respect to the outstanding Notes, this Indenture, the Subsidiary Guarantees and the Security Documents and cause the release of all Liens on the Collateral granted under the Security Documents (“Legal Defeasance”). Such Legal Defeasance means that the Issuer shall be deemed to have paid and discharged the entire indebtedness represented by the outstanding Notes, and satisfied all of

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its obligations with respect to the Notes, except for: (1) the rights of Holders to receive payments in respect of the principal of, premium, if any, and interest on the Notes when such payments are due, (2) the Issuer’s obligations with respect to the Notes concerning issuing temporary Notes, registration of Notes, mutilated, destroyed, lost or stolen Notes and the maintenance of an office or agency for payments, (3) the rights, powers, trust, duties and immunities of the Trustee and the Issuer’s obligations in connection therewith and (4) the Legal Defeasance provisions of this Section 8.1. In addition, the Issuer may, at its option and at any time, elect to terminate its obligations under the Notes, this Indenture, the Subsidiary Guarantees and the Security Documents, cause the release of all Liens on the Collateral granted under the Security Documents, terminate its obligations with respect to covenants contained in Sections 4.4, 4.5, 4.8 and 4.10 through 4.20 and Article V and the operation of clauses (6), (7) (with respect to Significant Subsidiaries), (8) or (9) of Section 6.1 and the limitations described in clause (3) of the first paragraph of Section 5.1 (“Covenant Defeasance”) and thereafter any omission to comply with such obligations shall not constitute a Default or Event of Default with respect to the Notes. The Issuer may exercise its Legal Defeasance option notwithstanding its prior exercise of its Covenant Defeasance option. In the event of Legal Defeasance, payment of the Notes may not be accelerated because of an Event of Default with respect thereto. In the event of Covenant Defeasance, payment of the Notes may not be accelerated because of an Event of Default specified in clause (4), (5), (6), (7) (with respect to only to Significant Subsidiaries), (8), (9) or (10) of Section 6.1 or because of the failure of the Issuer to comply with clause (3) of the first paragraph of Section 5.1. If the Issuer exercises its Legal Defeasance option or its Covenant Defeasance option, each Subsidiary Guarantor will be released from its obligations with respect to its Subsidiary Guarantee and all Liens on the Collateral will be released.

In order to exercise either Legal Defeasance or Covenant Defeasance:

(1) the Issuer must irrevocably deposit with the Trustee, in trust, for the benefit of the Holders cash in United States dollars, non-callable U.S. Government Obligations, or a combination thereof, in such amounts as will be sufficient, in the opinion of a nationally recognized firm of independent public accountants, to pay the principal of, premium, if any, and interest on the Notes on the stated date for payment thereof or on the applicable Redemption Date, as the case may be;

(2) in the case of Legal Defeasance, the Issuer shall have delivered to the Trustee an Opinion of Counsel in the United States reasonably acceptable to the Trustee confirming that (a) the Issuer has received from, or there has been published by, the Internal Revenue Service a ruling or (b) since the date of this Indenture, there has been a change in the applicable federal income tax law, in either case to the effect that, and based thereon such Opinion of Counsel shall confirm that, the Holders will not recognize income, gain or loss for federal income tax purposes as a result of such Legal Defeasance and will be subject to federal income tax on the same amounts, in the

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same manner and at the same times as would have been the case if such Legal Defeasance had not occurred;

(3) in the case of Covenant Defeasance, the Issuer shall have delivered to the Trustee an Opinion of Counsel in the United States reasonably acceptable to the Trustee confirming that the Holders will not recognize income, gain or loss for federal income tax purposes as a result of such Covenant Defeasance and will be subject to federal income tax on the same amounts, in the same manner and at the same times as would have been the case if such Covenant Defeasance had not occurred;

(4) no Default or Event of Default, of which the Trustee is deemed to have notice, shall have occurred and be continuing on the date of such deposit or insofar as Events of Default under clauses (7) or (8) of Section 6.1 from bankruptcy or insolvency events are concerned, at any time in the period ending on the 91st day after the date of deposit;

(5) such Legal Defeasance or Covenant Defeasance shall not result in a breach or violation of, or constitute a default under this Indenture or any other agreement or instrument to which the Issuer or any of its Restricted Subsidiaries is a party or by which the Issuer or any of its Restricted Subsidiaries is bound;

(6) the Issuer shall have delivered to the Trustee an Officer’s Certificate stating that the deposit was not made by the Issuer with the intent of preferring the Holders over any other creditors of the Issuer or with the intent of defeating, hindering, delaying or defrauding any other creditors of the Issuer or any Subsidiary Guarantor or others;

(7) the Issuer shall have delivered to the Trustee an Officer’s Certificate and an Opinion of Counsel, each stating that all conditions precedent provided for or relating to the Legal Defeasance or the Covenant Defeasance, as the case may be, have been complied with; provided, however, that such counsel may rely, as to matters of fact, on a certificate or certificates of officers of the Issuer; and

(8) the Issuer shall have delivered to the Trustee an Opinion of Counsel to the effect that after the 91st day following the deposit, the trust funds will not be subject to the effect of any applicable bankruptcy, insolvency, reorganization or similar laws affecting creditors’ rights generally; provided, however, that such counsel may rely, as to matters of fact, on a certificate or certificates of officers of the Issuer.

SECTION 8.2. Application of Trust Money.

The Trustee or Paying Agent shall hold in trust U.S. Legal Tender or U.S. Government Obligations deposited with it pursuant to Section 8.1, and shall apply the depos-

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ited U.S. Legal Tender and the money from U.S. Government Obligations in accordance with this Indenture to the payment of the principal of, premium, if any, and interest on the Notes. The Trustee shall be under no obligation to invest said U.S. Legal Tender or U.S. Government Obligations except as it may agree in writing with the Issuer.

The Issuer and the Subsidiary Guarantors shall pay jointly and severally and indemnify the Trustee against any tax, fee or other charge imposed on or assessed against the Legal Tender or U.S. Government Obligations deposited pursuant to Section 8.1 or the principal and interest received in respect thereof other than any such tax, fee or other charge which by law is for the account of the Holders of outstanding Notes.

SECTION 8.3. Repayment to the Issuer.

Subject to Section 8.1, the Trustee and the Paying Agent shall promptly pay to the Issuer upon request any excess U.S. Legal Tender or U.S. Government Obligations held by them at any time and thereupon shall be relieved from all liability with respect to such money. The Trustee and the Paying Agent shall pay to the Issuer upon request any money held by them for the payment of principal, interest or premium, if any, that remains unclaimed for one year; provided, however, that the Trustee or such Paying Agent, before being required to make any payment, may at the expense of the Issuer cause to be published once in a newspaper of general circulation in the City of New York or mail to each Holder entitled to such money notice that such money remains unclaimed and that after a date specified therein which shall be at least 30 days from the date of such publication or mailing any unclaimed balance of such money then remaining will be repaid to the Issuer. After payment to the Issuer, Holders entitled to such money must look to the Issuer for payment as general creditors unless an applicable law designates another Person.

SECTION 8.4. Reinstatement.

If the Trustee or Paying Agent is unable to apply any U.S. Legal Tender or U.S. Government Obligations in accordance with Section 8.1 by reason of any legal proceeding or by reason of any order or judgment of any court or governmental authority enjoining, restraining or otherwise prohibiting such application, the Issuer’s and the Subsidiary Guarantors’ obligations under this Indenture and the Notes and the Subsidiary Guarantees shall be revived and reinstated as though no deposit had occurred pursuant to Section 8.1 until such time as the Trustee or Paying Agent is permitted to apply all such U.S. Legal Tender or U.S. Government Obligations in accordance with Section 8.1; provided, however, that if the Issuer has made any payment of interest or premium, if any, on or principal of any Notes because of the reinstatement of its obligations, the Issuer shall be subrogated to the rights of the Holders of such Notes to receive such payment from the U.S. Legal Tender or U.S. Government Obligations held by the Trustee or Paying Agent.

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SECTION 8.5. Acknowledgment of Discharge by Trustee.

After (i) the conditions of Section 8.1 have been satisfied, (ii) the Issuer has paid or caused to be paid all other sums payable under this Indenture by the Issuer and (iii) the Issuer has delivered to the Trustee an Officer’s Certificate and an Opinion of Counsel, each stating that all conditions precedent referred to in clause (i) of this Section 8.5 relating to the satisfaction and discharge of this Indenture have been complied with, the Trustee upon request shall acknowledge in writing the discharge of the Issuer’s obligations under this Indenture except for those surviving obligations specified in Section 8.1, provided the legal counsel delivering such Opinion of Counsel may rely as to matters of fact on one or more Officer’s Certificates of the Issuer.

ARTICLE IX.

MODIFICATION OF THE INDENTURE

SECTION 9.1. Without Consent of Holders.

Without the consent of any Holder, the Issuer, the Subsidiary Guarantors and the Trustee or the Collateral Agent, as applicable, may amend this Indenture, the Notes, the Intercreditor Agreement and the Security Documents to:

(1) cure any ambiguity, omission, defect, mistake or inconsistency;

(2) provide for the assumption by a successor corporation of the obligations of the Issuer or any Subsidiary Guarantor under this Indenture;

(3) provide for uncertificated Notes in addition to or in place of certificated Notes (provided that the uncertificated Notes are issued in registered form for purposes of Section 163(f) of the Code, or in a manner such that the uncertificated Notes are described in Section 163(f)(2)(B) of the Code);

(4) add Guarantees with respect to the Notes, including Subsidiary Guarantees, or release a Subsidiary Guarantor from its Subsidiary Guarantee and terminate such Subsidiary Guarantee; provided that the release and termination is in accord with the applicable provisions of this Indenture;

(5) secure the Notes or Subsidiary Guarantees;

(6) add to the covenants of the Issuer or a Subsidiary Guarantor for the benefit of the Holders or surrender any right or power conferred upon the Issuer or a Subsidiary Guarantor;

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(7) make any change that does not adversely affect the rights of any Holder;

(8) comply with any requirement of the SEC in connection with the qualification of this Indenture under the TIA;

(9) conform the text of the Indenture, the Subsidiary Guarantees or the Notes to any provision of the “Description of notes” in the preliminary offering memorandum dated April 13, 2010 relating to the offer and sale of the Notes to the extent that such provision in such “Description of notes” was intended to be a verbatim recitation of a provision of this Indenture, the Subsidiary Guarantees or the Notes;

(10) provide for the issuance of exchange securities which shall have terms substantially identical in all respects to the Notes (except that the transfer restrictions contained in the Notes shall be modified or eliminated as appropriate) and which shall be treated, together with any outstanding Notes, as a single class of securities;

(11) provide for the succession of a successor Trustee or successor Collateral Agent under this Indenture;

(12) expand the Collateral securing the Notes or Subsidiary Guarantees, and, in the case of the Security Documents, to or for the benefit of the other secured parties named therein or to confirm and evidence the release, termination or discharge of any Subsidiary Guarantee of or Lien securing the Notes when such release, termination or discharge is permitted by this Indenture and the Security Documents or as required by the Intercreditor Agreement;

(13) provide for the accession or succession of any parties to the Intercreditor Agreement or the Security Documents (and other amendments that are administrative or ministerial in nature) in connection with an amendment, renewal, extension, substitution, refinancing, restructuring, replacement, supplementing or other modification from time to time of the Senior Secured Credit Agreement, the Notes or any other agreement or action that is not prohibited by this Indenture;

(14) provide for the release or addition of Collateral in accordance with the terms of this Indenture, the Intercreditor Agreement and the Security Documents; or

(15) provide security for additional borrowings under the Credit Facility that are incurred in accordance with this Indenture.

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SECTION 9.2. With Consent of Holders.

All other modifications and amendments of this Indenture, the Notes, the Intercreditor Agreement and the Security Documents may be made, subject to certain exceptions, with the consent of the Holders of a majority in principal amount of the Notes then outstanding (including without limitation, consents obtained in connection with a purchase of, or tender offer or exchange offer for, Notes) and, subject to certain exceptions, any past default or compliance with any provisions may be waived with the consent of the Holders of a majority in principal amount of the Notes then outstanding (including, without limitation, consents obtained in connection with a purchase of, or tender offer or exchange offer for, Notes).

Subject to certain exceptions, the Intercreditor Agreement and the Security Documents may be amended with the consent of the Holders of a majority in principal amount of the Notes then outstanding (voting as one class) and any past default or noncompliance with any provisions in the Intercreditor Agreement and the Security Documents may also be waived with the consent of the Holders of a majority in principal amount of the Notes then outstanding (voting as one class). Such amendments may not, without the consent of the Holders of 75% in principal amount of the Notes then outstanding (voting as one class), release all or substantially all of the Collateral other than in accordance with this Indenture, the Intercreditor Agreement and the Security Documents. However, without the consent of each Holder of an outstanding Note affected, no amendment may, among other things:

(1) reduce the principal amount of Notes whose Holders must consent to an amendment, supplement or waiver;

(2) reduce the stated rate of or extend the stated time for payment of interest on any Note;

(3) reduce the principal of or extend the Stated Maturity of any Note;

(4) reduce the amount payable upon redemption of any Note pursuant to Section 3.3, or change the time at which any Note may be redeemed pursuant to Section 3.3, (other than Sections 4.15 and 4.16);

(5) make any Note payable in money other than that stated in the Note;

(6) impair the right of any Holder to receive payment of, premium, if any, principal of and interest on such Holder’s Notes on or after the due dates therefor or to institute suit for the enforcement of any payment on or with respect to such Holder’s Notes;

(7) make any change in the amendment provisions which require each Holder’s consent or in the waiver provisions;

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(8) modify the Subsidiary Guarantees in any manner adverse to the holders of the Notes; or

(9) make any change to or modify the ranking of the Notes that would adversely affect the Holders.

The consent of the Holders is not necessary under this Indenture to approve the particular form of any proposed amendment. It is sufficient if such consent approves the substance of the proposed amendment. A consent to any amendment or waiver under this Indenture or the Security Documents by any Holder given in connection with a tender of such Holder’s Notes will not be rendered invalid by such tender. After an amendment under this Indenture becomes effective, the Issuer is required to mail to the Holders a notice briefly describing such amendment. However, failure to give such notice to all the Holders, or any defect in the notice, will not impair or affect the validity of the amendment.

No amendment of, or supplement or waiver to, this Indenture, the Notes or the Security Documents (other than the Intercreditor Agreement) shall be permitted to be effected which is in violation of or inconsistent with the terms of the Intercreditor Agreement. No amendment of, or supplement to, the Intercreditor Agreement shall be permitted to be effected without the consent of the First-Lien Collateral Agent and the Collateral Agent.

SECTION 9.3. Compliance with Trust Indenture Act.

Every amendment, waiver or supplement of this Indenture or the Notes shall comply with the TIA as then in effect; provided, however, that this Section 9.3 shall not of itself require that this Indenture or the Trustee be qualified under the TIA or constitute any admission or acknowledgment by any party hereto that any such qualification is required prior to the time this Indenture and the Trustee are required by the TIA to be so qualified.

SECTION 9.4. Revocation and Effect of Consents.

Until an amendment, waiver or supplement becomes effective, a consent to it by a Holder is a continuing consent by the Holder and every subsequent Holder of a Note or portion of a Note that evidences the same debt as the consenting Holder’s Note, even if notation of the consent is not made on any Note. Subject to the following paragraph, any such Holder or subsequent Holder may revoke the consent as to such Holder’s Note or portion of such Note by notice to the Trustee or the Issuer received before the date on which the Trustee receives an Officer’s Certificate certifying that the Holders of the requisite principal amount of Notes have consented (and not theretofore revoked such consent) to the amendment, supplement or waiver. An amendment, supplement or waiver becomes effective upon receipt by the Trustee of such Officer’s Certificate and evidence of consent by the Holders of the requisite percentage in principal amount of outstanding Notes.

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The Issuer may, but shall not be obligated to, fix a Record Date for the purpose of determining the Holders entitled to consent to any amendment, supplement or waiver, which Record Date shall be at least 30 days prior to the first solicitation of such consent. If a Record Date is fixed, then notwithstanding the second sentence of the immediately preceding paragraph, those Persons who were Holders at such Record Date (or their duly designated proxies), and only those Persons, shall be entitled to revoke any consent previously given, whether or not such Persons continue to be Holders after such Record Date. No such consent shall be valid or effective for more than 90 days after such Record Date unless consents from Holders of the requisite percentage in principal amount of outstanding Notes required under this Indenture for the effectiveness of such consents shall have also been given and not revoked within such 90 day period.

SECTION 9.5. Notation on or Exchange of Notes.

If an amendment, supplement or waiver changes the terms of a Note, the Trustee may require the Holder of such Note to deliver it to the Trustee. The Trustee may place an appropriate notation on the Note about the changed terms and return it to the Holder. Alternatively, if the Issuer or the Trustee so determines, the Issuer in exchange for the Note shall issue and the Trustee shall authenticate a new Note that reflects the changed terms.

SECTION 9.6. Trustee To Sign Amendments, Etc.

The Trustee shall execute any amendment, supplement or waiver authorized pursuant to this Article IX; provided, however, that the Trustee may, but shall not be obligated to, execute any such amendment, supplement or waiver which affects the Trustee’s own rights, duties or immunities under this Indenture. In executing such supplement or waiver the Trustee shall be entitled to receive indemnity satisfactory to it, and shall be fully protected in relying upon an Opinion of Counsel and an Officer’s Certificate of the Issuer, stating that no event of default shall occur as a result of such amendment, supplement or waiver and that the execution of any amendment, supplement or waiver authorized pursuant to this Article IX is authorized or permitted by this Indenture, provided the legal counsel delivering such Opinion of Counsel may rely as to matters of fact on one or more Officer’s Certificates of the Issuer. Such Opinion of Counsel shall not be an expense of the Trustee.

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ARTICLE X.

[RESERVED]

ARTICLE XI.

MISCELLANEOUS

SECTION 11.1. TIA Controls.

If any provision of this Indenture limits, qualifies, or conflicts with another provision which is required to be included in this Indenture by the TIA, the required provision shall control; provided, however, that this Section 11.1 shall not of itself require that this Indenture or the Trustee be qualified under the TIA or constitute any admission or acknowledgment by any party hereto that any such qualification is required prior to the time this Indenture and the Trustee are required by the TIA to be so qualified.

SECTION 11.2. Notices.

Any notices or other communications required or permitted under this Indenture shall be in writing, and shall be sufficiently given if made by hand delivery, by telex, by telecopier or registered or certified mail, postage prepaid, return receipt requested, addressed as follows:

if to the Issuer and/or any Subsidiary Guarantor:

c/o ATP Oil & Gas Corporation

▇▇▇▇ ▇▇▇▇ ▇▇▇ ▇▇▇▇▇, ▇▇▇▇▇ ▇▇▇

▇▇▇▇▇▇▇, ▇▇ ▇▇▇▇▇

Fax Number: (▇▇▇) ▇▇▇-▇▇▇▇

Attn: Chief Financial Officer

if to the Trustee:

The Bank of New York Mellon Trust Company, N.A.

▇▇▇ ▇▇▇▇▇▇ ▇▇▇▇▇▇, ▇▇▇▇ ▇▇▇▇▇▇

▇▇▇▇▇▇▇, ▇▇▇▇▇ ▇▇▇▇▇

Fax Number: (▇▇▇) ▇▇▇-▇▇▇▇

Attn: Corporate Trust Administration, re: ATP Oil & Gas Corp.

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The Issuer, the Subsidiary Guarantors and the Trustee by written notice to the other may designate additional or different addresses for notices to such Person. Any notice or communication to the Issuer or the Trustee shall be deemed to have been given or made as of the date so delivered if hand delivered; when receipt is acknowledged, if faxed; and five (5) calendar days after mailing if sent by registered or certified mail, postage prepaid (except that a notice of change of address shall not be deemed to have been given until actually received by the addressee).

Any notice or communication mailed to a Holder shall be mailed to him by first class mail or other equivalent means at his address as it appears on the registration books of the Registrar ten (10) days prior to such mailing and shall be sufficiently given to him if so mailed within the time prescribed.

Any notice or communication shall also be so mailed to any Person described in TIA § 313(c), to the extent required by the TIA.

Failure to mail a notice or communication to a Holder or any defect in it shall not affect its sufficiency with respect to other Holders. If a notice or communication is mailed in the manner provided above, it is duly given, whether or not the addressee receives it.

SECTION 11.3. Communications by Holders with Other Holders.

Holders may communicate pursuant to TIA § 312(b) with other Holders with respect to their rights under this Indenture or the Notes. The Issuer, the Trustee, the Registrar and any other Person shall have the protection of TIA § 312(c).

SECTION 11.4. Certificate and Opinion as to Conditions Precedent.

Upon any request or application by the Issuer and/or any Subsidiary Guarantor to the Trustee to take any action under this Indenture, the Issuer and/or any Subsidiary Guarantor shall furnish to the Trustee:

(1) an Officer’s Certificate, in form and substance satisfactory to the Trustee, stating that, in the opinion of the signers, all conditions precedent to be performed by the Issuer, if any, provided for in this Indenture relating to the proposed action have been complied with; and

(2) an Opinion of Counsel stating that, in the opinion of such counsel, all such conditions precedent to be performed by the Issuer, if any, provided for in this Indenture relating to the proposed action have been complied with (which counsel, as to factual matters, may rely on an Officer’s Certificate).

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SECTION 11.5. Statements Required in Certificate or Opinion.

Each certificate or opinion with respect to compliance with a condition or covenant provided for in this Indenture, other than the Officer’s Certificate required by Section 4.6, shall comply with TIA § 314(e) and include:

(1) a statement that the Person making such certificate or opinion has read such covenant or condition;

(2) a brief statement as to the nature and scope of the examination or investigation upon which the statements or opinions contained in such certificate or opinion are based;

(3) a statement that, in the opinion of such Person, he has made such examination or investigation as is reasonably necessary to enable him to express an informed opinion as to whether or not such covenant or condition has been complied with; and

(4) a statement as to whether or not, in the opinion of each such Person, such condition or covenant has been complied with.

SECTION 11.6. Rules by Trustee, Paying Agent, Registrar.

The Trustee may make reasonable rules in accordance with the Trustee’s customary practices for action by or at a meeting of Holders. The Paying Agent or Registrar may make reasonable rules for its functions.

SECTION 11.7. Legal Holidays.

A “Legal Holiday” used with respect to a particular place of payment is a Saturday, a Sunday or a day on which commercial banking institutions in New York, New York, or Houston, Texas or at such place of payment are authorized or required by law to close. If a payment date is a Legal Holiday at such place, payment may be made at such place on the next succeeding day that is not a Legal Holiday, and no interest shall accrue for the intervening period.

SECTION 11.8. Governing Law.

THIS INDENTURE , THE NOTES, THE SUBSIDIARY GUARANTEES, THE REGISTRATION RIGHTS AGREEMENT, THE SECURITY DOCUMENTS (OTHER THAN THE MORTGAGES) AND THE INTERCREDITOR AGREEMENT SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK. Each of the parties hereto agrees to submit to the jurisdiction of

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the courts of the State of New York in any action or proceeding arising out of or relating to this Indenture.

SECTION 11.9. No Adverse Interpretation of Other Agreements.

This Indenture may not be used to interpret another indenture, loan or debt agreement of the Issuer or any of its respective Subsidiaries. Any such indenture, loan or debt agreement may not be used to interpret this Indenture.

SECTION 11.10. No Personal Liability.

No director, officer, employee, incorporator, stockholder, member, partner, manager or trustee of the Issuer or director, officer, employee, incorporator or stockholder of any Subsidiary Guarantor, as such, shall have any liability for any of the Issuer’s obligations under the Notes, the Subsidiary Guarantors’ obligations under the Subsidiary Guarantees or this Indenture or any claim based on, in respect of, by reason of, these obligations. Each Holder, by accepting a Note, waives and releases all such liability. The waiver and release are part of the consideration for issuance of the Notes. The waiver may not be effective to waive liabilities under the federal securities laws and it is the view of the SEC that such a waiver is against public policy.

SECTION 11.11. Successors.

All agreements of the Issuer and the Subsidiary Guarantors in this Indenture, the Notes and the Subsidiary Guarantees shall bind their successors. All agreements of the Trustee in this Indenture shall bind its successors.

SECTION 11.12. Duplicate Originals.

All parties may sign any number of copies of this Indenture. Each signed copy shall be an original, but all of them together shall represent the same agreement.

SECTION 11.13. Severability.

In case any one or more of the provisions in this Indenture or in the Notes shall be held invalid, illegal or unenforceable, in any respect for any reason, the validity, legality and enforceability of any such provision in every other respect and of the remaining provisions shall not in any way be affected or impaired thereby, it being intended that all of the provisions hereof shall be enforceable to the full extent permitted by law.

SECTION 11.14. Independence of Covenants.

All covenants and agreements in this Indenture and the Notes shall be given independent effect so that if any particular action or condition is not permitted by any of such

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covenants, the fact that it would be permitted by an exception to, or otherwise be within the limitations of, another covenant shall not avoid the occurrence of a Default or an Event of Default if such action is taken or condition exists.

SECTION 11.15. Waiver of Jury Trial.

EACH OF THE ISSUER, THE SUBSIDIARY GUARANTORS AND THE TRUSTEE IRREVOCABLY WAIVES, TO THE FULLEST EXTENT PERMITTED BY APPLICABLE LAW, ANY AND ALL RIGHT TO TRIAL BY JURY IN ANY LEGAL PROCEEDING ARISING OUT OF OR RELATING TO THIS INDENTURE, THE NOTES OR THE TRANSACTIONS CONTEMPLATED HEREBY.

SECTION 11.16. U.S.A. Patriot Act.

The parties hereto acknowledge that in accordance with Section 326 of the U.S.A. Patriot Act, the Trustee, like all financial institutions and in order to help fight the funding of terrorism and money laundering, is required to obtain, verify, and record information that identifies each person or legal entity that establishes a relationship or opens an account with the Trustee. The parties to this Indenture agree that they will provide the Trustee with such information within their possession or control as it may reasonably request in order for the Trustee to satisfy the requirements of the U.S.A. Patriot Act.

ARTICLE XII.

SUBSIDIARY GUARANTEE OF NOTES

SECTION 12.1. Unconditional Subsidiary Guarantee.

Subject to the provisions of this Article XII, each Subsidiary Guarantor, if any, hereby, jointly and severally, unconditionally and fully guarantees, on a senior basis to each Holder of a Note authenticated and delivered by the Trustee and to the Trustee and its successors and assigns, irrespective of the validity and enforceability of this Indenture, the Notes or the obligations of the Issuer or any other Subsidiary Guarantors to the Holders or the Trustee under this Indenture or thereunder, that: (a) the principal of, premium, if any, and interest on the Notes shall be duly and punctually paid in full when due, whether at maturity, upon redemption at the option of Holders pursuant to the provisions of the Notes relating thereto, by acceleration or otherwise, and interest on the overdue principal and (to the extent permitted by law) interest, if any, on the Notes and all other obligations of the Issuer or the Subsidiary Guarantors to the Holders or the Trustee under this Indenture or thereunder (including

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amounts due the Trustee under Section 7.7 hereof) and all other obligations shall be promptly paid in full or performed, all in accordance with the terms hereof and thereof; and (b) in case of any extension of time of payment or renewal of any Notes or any of such other obligations, the same shall be promptly paid in full when due or performed in accordance with the terms of the extension or renewal, whether at maturity, by acceleration or otherwise. Failing payment when due of any amount so guaranteed, or failing performance of any other obligation of the Issuer to the Holders under this Indenture or under the Notes, for whatever reason, each Subsidiary Guarantor shall be obligated to pay, or to perform or cause the performance of, the same immediately. An Event of Default under this Indenture or the Notes shall constitute an event of default under the Subsidiary Guarantees, and shall entitle the Holders of Notes to accelerate the obligations of the Subsidiary Guarantors under this Indenture in the same manner and to the same extent as the obligations of the Issuer.

Each of the Subsidiary Guarantors hereby agrees that its obligations under this Indenture shall be unconditional, irrespective of the validity, regularity or enforceability of the Notes or this Indenture, the absence of any action to enforce the same, any waiver or consent by any Holder of the Notes with respect to any provisions hereof or thereof, any release of any other Subsidiary Guarantor, the recovery of any judgment against the Issuer, any action to enforce the same, whether or not a Subsidiary Guarantee is affixed to any particular Note, or any other circumstance which might otherwise constitute a legal or equitable discharge or defense of a guarantor. Each of the Subsidiary Guarantors hereby waives the benefit of diligence, presentment, demand of payment, filing of claims with a court in the event of insolvency or bankruptcy of the Issuer, any right to require a proceeding first against the Issuer, protest, notice and all demands whatsoever and covenants that its Subsidiary Guarantee shall not be discharged except by complete performance of the obligations contained in the Notes, this Indenture and this Subsidiary Guarantee. Each Subsidiary Guarantee is a guarantee of payment and not of collection. If any Holder or the Trustee is required by any court or otherwise to return to the Issuer or to any Subsidiary Guarantor, or any custodian, trustee, liquidator or other similar official acting in relation to the Issuer or such Subsidiary Guarantor, any amount paid by the Issuer or such Subsidiary Guarantor to the Trustee or such Holder, this Subsidiary Guarantee, to the extent theretofore discharged, shall be reinstated in full force and effect. Each Subsidiary Guarantor further agrees that, as between it, on the one hand, and the Holders of Notes and the Trustee, on the other hand, (a) subject to this Article XII, the maturity of the obligations guaranteed hereby may be accelerated as provided in Article VI hereof for the purposes of its Subsidiary Guarantee, notwithstanding any stay, injunction or other prohibition preventing such acceleration in respect of the obligations guaranteed hereby, and (b) in the event of any acceleration of such obligations as provided in Article VI hereof, such obligations (whether or not due and payable) shall forthwith become due and payable by the Subsidiary Guarantors for the purpose of its Subsidiary Guarantee.

No stockholder, officer, director, employee, partner, incorporator, member, manager or trustee, past, present or future, of any Subsidiary Guarantor, as such, shall have

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any personal liability under the Subsidiary Guarantees by reason of his, her or its status as such stockholder, officer, director, employee, partner, incorporator, member, manager or trustee.

SECTION 12.2. Limitations on Subsidiary Guarantees.

The obligations of each Subsidiary Guarantor under its Subsidiary Guarantee will be limited to the maximum amount which, after giving effect to all other contingent and fixed liabilities of such Subsidiary Guarantor and after giving effect to any collections from or payments made by or on behalf of any other Subsidiary Guarantor in respect of the obligations of such other Subsidiary Guarantor under its Subsidiary Guarantee or pursuant to its contribution obligations under this Indenture, will result in the obligations of such Subsidiary Guarantor under its Subsidiary Guarantee not constituting a fraudulent conveyance or fraudulent transfer under federal or state law.

SECTION 12.3. Execution and Delivery of Subsidiary Guarantee Notation.

To further evidence its Subsidiary Guarantee set forth in Section 12.1, each Subsidiary Guarantor hereby agrees that a notation of such Subsidiary Guarantee, substantially in the form of Exhibit D herein, shall be endorsed on each Note authenticated and delivered by the Trustee. Such notation shall be executed on behalf of each Subsidiary Guarantor by either manual or facsimile signature of one Officer of each Subsidiary Guarantor, who, in each case, shall have been duly authorized to so execute by all requisite corporate action. The validity and enforceability of any Subsidiary Guarantee shall not be affected by the fact that such notation is not affixed to any particular Note.

Each of the Subsidiary Guarantors hereby agrees that its Subsidiary Guarantee set forth in Section 12.1 shall remain in full force and effect notwithstanding any failure to endorse on each Note a notation of such Subsidiary Guarantee.

If an Officer of a Subsidiary Guarantor whose signature is on this Indenture or on a notation of a Subsidiary Guarantee no longer holds that office at the time the Trustee authenticates the Note on which such notation is endorsed or at any time thereafter, such Subsidiary Guarantor’s Subsidiary Guarantee of such Note shall be valid nevertheless.

The delivery of any Note by the Trustee, after the authentication thereof under this Indenture, shall constitute due delivery of any Subsidiary Guarantee set forth in this Indenture on behalf of each Subsidiary Guarantor.

SECTION 12.4. Release of a Subsidiary Guarantor.

(a) If no Default exists or would exist under this Indenture, (i) upon the sale or disposition of all of the Capital Stock of a Subsidiary Guarantor by the Issuer or a Re-

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stricted Subsidiary of such Issuer in a transaction constituting an Asset Disposition in accordance with Section 4.16, or upon the consolidation or merger of a Subsidiary Guarantor with or into any Person in compliance with Article V (in each case, other than to either Issuer or an Affiliate of the Issuer or a Restricted Subsidiary), or (ii) upon the designation of a Subsidiary Guarantor as an Unrestricted Subsidiary in accordance the requirements therefor set forth in the definition of “Unrestricted Subsidiary” or in connection with any Legal Defeasance or satisfaction and discharge of the Notes as provided in Section 8.1, such Subsidiary Guarantor and each Subsidiary of such Subsidiary Guarantor that is also a Subsidiary Guarantor shall be deemed released from all obligations under this Article XII without any further action required on the part of the Trustee or any Holder; provided, however, that each such Subsidiary Guarantor is sold or disposed of or designated in accordance with this Indenture. Any Subsidiary Guarantor not so released or the entity surviving such Subsidiary Guarantor, as applicable, shall remain or be liable under its Subsidiary Guarantee as provided in this Article XII.

(b) The Trustee shall deliver an appropriate instrument evidencing the release of a Subsidiary Guarantor upon receipt of a request by the Issuer or such Subsidiary Guarantor accompanied by an Officer’s Certificate and an Opinion of Counsel certifying as to the compliance with this Section 12.4, provided the legal counsel delivering such Opinion of Counsel may rely as to matters of fact on one or more Officer’s Certificates of the Issuer.

The Trustee shall execute any documents reasonably requested by the Issuer or a Subsidiary Guarantor in order to evidence the release of such Subsidiary Guarantor from its obligations under its Subsidiary Guarantee endorsed on the Notes and under this Article XII.

Except as set forth in Articles Four and Five and this Section 12.4, nothing contained in this Indenture or in any of the Notes shall prevent any consolidation or merger of a Subsidiary Guarantor with or into the Issuer or another Subsidiary Guarantor or shall prevent any sale or conveyance of the property of a Subsidiary Guarantor as an entirety or substantially as an entirety to the Issuer or another Subsidiary Guarantor.

SECTION 12.5. Waiver of Subrogation.

Until this Indenture is discharged and all of the Notes are discharged and paid in full, each Subsidiary Guarantor hereby irrevocably waives and agrees not to exercise any claim or other rights which it may now or hereafter acquire against the Issuer that arise from the existence, payment, performance or enforcement of the Issuer’s obligations under the Notes or this Indenture and such Subsidiary Guarantor’s obligations under its Subsidiary Guarantee and this Indenture, in any such instance including, without limitation, any right of subrogation, reimbursement, exoneration, contribution, indemnification, and any right to participate in any claim or remedy of the Holders against the Issuer, whether or not such claim, remedy or right arises in equity, or under contract, statute or common law, including, without limitation, the right to take or receive from the Issuer, directly or indirectly, in cash or other property or by set-off or in any other manner, payment or security on account of such claim or

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other rights. If any amount shall be paid to any Subsidiary Guarantor in violation of the preceding sentence and any amounts owing to the Trustee or the Holders of Notes under the Notes, this Indenture, or any other document or instrument delivered under or in connection with such agreements or instruments, shall not have been paid in full, such amount shall have been deemed to have been paid to such Subsidiary Guarantor for the benefit of, and held in trust for the benefit of, the Trustee or the Holders and shall forthwith be paid to the Trustee for the benefit of itself or such Holders to be credited and applied to the obligations in favor of the Trustee or the Holders, as the case may be, whether matured or unmatured, in accordance with the terms of this Indenture. Each Subsidiary Guarantor acknowledges that it will receive direct and indirect benefits from the financing arrangements contemplated by this Indenture and that the waiver set forth in this Section 12.5 is knowingly made in contemplation of such benefits.

SECTION 12.6. Immediate Payment.

Each Subsidiary Guarantor agrees to make immediate payment to the Trustee on behalf of the Holders of all obligations under the Notes and this Indenture owing or payable to the respective Holders upon receipt of a demand for payment therefor by the Trustee to such Subsidiary Guarantor in writing.

SECTION 12.7. No Set-Off.

Each payment to be made by a Subsidiary Guarantor under this Indenture in respect of the obligations under the Notes and this Indenture shall be payable in the currency or currencies in which such obligations are denominated, and shall be made without set-off, counterclaim, reduction or diminution of any kind or nature.

SECTION 12.8. Obligations Absolute.

The obligations of each Subsidiary Guarantor under this Indenture are and shall be absolute and unconditional and any monies or amounts expressed to be owing or payable by each Subsidiary Guarantor under this Indenture which may not be recoverable from such Subsidiary Guarantor on the basis of a Subsidiary Guarantee shall be recoverable from such Subsidiary Guarantor as a primary obligor and principal debtor in respect thereof.

SECTION 12.9. Obligations Continuing.

The obligations of each Subsidiary Guarantor under this Indenture shall be continuing and shall remain in full force and effect until all the obligations have been paid and satisfied in full. Each Subsidiary Guarantor agrees with the Trustee that it will from time to time deliver to the Trustee suitable acknowledgments of this continued liability under this Indenture and under any other instrument or instruments in such form as counsel to the Trustee may advise and as will prevent any action brought against it in respect of any default under

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this Indenture being barred by any statute of limitations now or hereafter in force and, in the event of the failure of a Subsidiary Guarantor so to do, it hereby irrevocably appoints the Trustee the attorney and agent of such Subsidiary Guarantor to make, execute and deliver such written acknowledgment or acknowledgments or other instruments as may from time to time become necessary or advisable, in the judgment of the Trustee on the advice of counsel, to fully maintain and keep in force the liability of such Subsidiary Guarantor under this Indenture.

SECTION 12.10. Obligations Not Reduced.

The obligations of each Subsidiary Guarantor under this Indenture shall not be satisfied, reduced or discharged solely by the payment of such principal, premium, if any, interest, fees and other monies or amounts as may at any time prior to discharge of this Indenture pursuant to Article VIII be or become owing or payable under or by virtue of or otherwise in connection with the Notes or this Indenture.

SECTION 12.11. Obligations Reinstated.

The obligations of each Subsidiary Guarantor under this Indenture shall continue to be effective or shall be reinstated, as the case may be, if at any time any payment which would otherwise have reduced the obligations of any Subsidiary Guarantor under this Indenture (whether such payment shall have been made by or on behalf of the Issuer or by or on behalf of a Subsidiary Guarantor) is rescinded or reclaimed from any of the Holders upon the insolvency, bankruptcy, liquidation or reorganization of the Issuer or any Subsidiary Guarantor or otherwise, all as though such payment had not been made. If demand for, or acceleration of the time for, payment by the Issuer is stayed upon the insolvency, bankruptcy, liquidation or reorganization of the Issuer, all such Indebtedness otherwise subject to demand for payment or acceleration shall nonetheless be payable by each Subsidiary Guarantor as provided herein.

SECTION 12.12. Obligations Not Affected.

The obligations of each Subsidiary Guarantor under this Indenture shall not be affected, impaired or diminished in any way by any act, omission, matter or thing whatsoever, occurring before, upon or after any demand for payment under this Indenture (and whether or not known or consented to by any Subsidiary Guarantor or any of the Holders) which, but for this provision, might constitute a whole or partial defense to a claim against any Subsidiary Guarantor under this Indenture or might operate to release or otherwise exonerate any Subsidiary Guarantor from any of its obligations under this Indenture or otherwise affect such obligations, whether occasioned by default of any of the Holders or otherwise, including, without limitation:

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(a) any limitation of status or power, disability, incapacity or other circumstance relating to the Issuer or any other person, including any insolvency, bankruptcy, liquidation, reorganization, readjustment, composition, dissolution, winding up or other proceeding involving or affecting the Issuer or any other person;

(b) any irregularity, defect, unenforceability or invalidity in respect of any Indebtedness or other obligation of the Issuer or any other person under this Indenture, the Notes or any other document or instrument;

(c) any failure of the Issuer, whether or not without fault on its part, to perform or comply with any of the provisions of this Indenture or the Notes, or to give notice thereof to a Subsidiary Guarantor;

(d) the taking or enforcing or exercising or the refusal or neglect to take or enforce or exercise any right or remedy from or against the Issuer or any other person or their respective assets or the release or discharge of any such right or remedy;

(e) the granting of time, renewals, extensions, compromises, concessions, waivers, releases, discharges and other indulgences to the Issuer or any other Person;

(f) any change in the time, manner or place of payment of, or in any other term of, any of the Notes, or any other amendment, variation, supplement, replacement or waiver of, or any consent to departure from, any of the Notes or this Indenture, including, without limitation, any increase or decrease in the principal amount of or premium, if any, or interest on any of the Notes;

(g) any change in the ownership, control, name, objects, businesses, assets, capital structure or constitution of the Issuer or a Subsidiary Guarantor;

(h) any merger or amalgamation of the Issuer or a Subsidiary Guarantor with any Person or Persons;

(i) the occurrence of any change in the laws, rules, regulations or ordinances of any jurisdiction by any present or future action of any governmental authority or court amending, varying, reducing or otherwise affecting, or purporting to amend, vary, reduce or otherwise affect, any of the Issuer’s obligations under the Notes or this Indenture or the obligations of a Subsidiary Guarantor under its Subsidiary Guarantee; and

(j) any other circumstance (other than by complete, irrevocable payment), including release of any other Subsidiary Guarantor pursuant to Section 12.4, that might otherwise constitute a legal or equitable discharge or defense of the Issuer under

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this Indenture or the Notes or of a Subsidiary Guarantor in respect of its Subsidiary Guarantee under this Indenture.

SECTION 12.13. Waiver.

Without in any way limiting the provisions of Section 12.1 hereof, each Subsidiary Guarantor hereby waives notice of acceptance hereof, notice of any liability of any Subsidiary Guarantor under this Indenture, notice or proof of reliance by the Holders upon the obligations of any Subsidiary Guarantor under this Indenture, and diligence, presentment, demand for payment on the Issuer, protest, notice of dishonor or non-payment of any of the Issuer’s obligations, under the notes or this Indenture, or other notice or formalities to the Issuer or any Subsidiary Guarantor of any kind whatsoever.

SECTION 12.14. No Obligation To Take Action Against the Issuer.

Neither the Trustee nor any other Person shall have any obligation to enforce or exhaust any rights or remedies or to take any other steps under any security for the Issuer’s obligations under the notes or this Indenture, or against the Issuer or any other Person or any Property of the Issuer or any other Person before the Trustee is entitled to demand payment and performance by any or all Subsidiary Guarantors of their liabilities and obligations under their Subsidiary Guarantees or under this Indenture.

SECTION 12.15. Dealing with the Issuer and Others.

The Holders, without releasing, discharging, limiting or otherwise affecting in whole or in part the obligations and liabilities of any Subsidiary Guarantor under this Indenture and without the consent of or notice to any Subsidiary Guarantor, may

(a) grant time, renewals, extensions, compromises, concessions, waivers, releases, discharges and other indulgences to the Issuer or any other Person;

(b) take or abstain from taking security or collateral from the Issuer or from perfecting security or collateral of the Issuer;

(c) release, discharge, compromise, realize, enforce or otherwise deal with or do any act or thing in respect of (with or without consideration) any and all collateral, mortgages or other security given by the Issuer or any third party with respect to the obligations or matters contemplated by this Indenture or the Notes;

(d) accept compromises or arrangements from the Issuer;

(e) apply all monies at any time received from the Issuer or from any security upon such part of the Issuer’s obligations under the Notes and this Indenture as the

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Holders may see fit or change any such application in whole or in part from time to time as the Holders may see fit; and

(f) otherwise deal with, or waive or modify their right to deal with, the Issuer and all other Persons and any security as the Holders or the Trustee may see fit.

SECTION 12.16. Default and Enforcement.

If any Subsidiary Guarantor fails to pay in accordance with Section 12.6 hereof, the Trustee may proceed in its name as trustee under this Indenture in the enforcement of the Subsidiary Guarantee of any such Subsidiary Guarantor and such Subsidiary Guarantor’s obligations thereunder and under this Indenture by any remedy provided by law, whether by legal proceedings or otherwise, and to recover from such Subsidiary Guarantor its obligations thereunder and under this Indenture.

SECTION 12.17. Amendment, Etc.

No amendment, modification or waiver of any provision of this Indenture relating to any Subsidiary Guarantor or consent to any departure by any Subsidiary Guarantor or any other Person from any such provision will in any event be effective unless it is signed by such Subsidiary Guarantor and the Trustee.

SECTION 12.18. Acknowledgment.

Each Subsidiary Guarantor hereby acknowledges communication of the terms of this Indenture and the Notes and consents to and approves of the same.

SECTION 12.19. Costs and Expenses.

Each Subsidiary Guarantor shall pay on demand by the Trustee any and all reasonable costs, fees and expenses (including, without limitation, legal fees on a solicitor and client basis) incurred by the Trustee, its agents, advisors and counsel or any of the Holders in enforcing any of their rights under any Subsidiary Guarantee.

SECTION 12.20. No Merger or Waiver; Cumulative Remedies.

No Subsidiary Guarantee shall operate by way of merger of any of the obligations of a Subsidiary Guarantor under any other agreement, including, without limitation, this Indenture. No failure to exercise and no delay in exercising, on the part of the Trustee or the Holders, any right, remedy, power or privilege under this Indenture or under this Indenture or the Notes, shall operate as a waiver thereof; nor shall any single or partial exercise of any right, remedy, power or privilege under this Indenture or under this Indenture or the Notes preclude any other or further exercise thereof or the exercise of any other right, remedy, pow-

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er or privilege. The rights, remedies, powers and privileges in the Subsidiary Guarantee and under this Indenture, the Notes and any other document or instrument between a Subsidiary Guarantor and/or the Issuer and the Trustee are cumulative and not exclusive of any rights, remedies, powers and privilege provided by law.

SECTION 12.21. Survival of Obligations.

Without prejudice to the survival of any of the other obligations of each Subsidiary Guarantor under this Indenture, the obligations of each Subsidiary Guarantor under Section 12.1 shall survive the payment in full of the Issuer’s obligations under the Notes and this Indenture and shall be enforceable against such Subsidiary Guarantor without regard to and without giving effect to any defense, right of offset or counterclaim available to or which may be asserted by the Issuer or any Subsidiary Guarantor.

SECTION 12.22. Subsidiary Guarantee in Addition to Other Obligations.

The obligations of each Subsidiary Guarantor under its Subsidiary Guarantee and this Indenture are in addition to and not in substitution for any other obligations to the Trustee or to any of the Holders in relation to this Indenture or the Notes and any guarantees or security at any time held by or for the benefit of any of them.

SECTION 12.23. Severability.

Any provision of this Article XII which is prohibited or unenforceable in any jurisdiction shall not invalidate the remaining provisions and any such prohibition or unenforceability in any jurisdiction shall not invalidate or render unenforceable such provision in any other jurisdiction unless its removal would substantially defeat the basic intent, spirit and purpose of this Indenture and this Article XII.

SECTION 12.24. Successors and Assigns.

Each Subsidiary Guarantee shall be binding upon and inure to the benefit of each Subsidiary Guarantor and the Trustee and the other Holders and their respective successors and permitted assigns, except that no Subsidiary Guarantor may assign any of its obligations under this Indenture or thereunder.

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ARTICLE XIII.

SECURITY

SECTION 13.1. Collateral and Security Documents; Further Assurances;

(a) The due and punctual payment of the principal of and interest on the Notes when and as the same shall be due and payable, whether on an Interest Payment Date, at maturity, by acceleration, repurchase, redemption or otherwise, and interest on the overdue principal of and interest on the Notes and performance of all other obligations of the Issuer and the Subsidiary Guarantors to the Holders, the Trustee or the Collateral Agent according to the terms hereunder or thereunder, shall be secured as provided in the Security Documents. The Trustee and the Issuer hereby acknowledge and agree that the Collateral Agent holds the Collateral in trust for the benefit of the Secured Parties, in each case pursuant to the terms of the Security Documents. Each Holder, by accepting a Note, consents and agrees to the terms of the Security Documents (including the provisions providing for the possession, use, release and foreclosure of Collateral) as the same may be in effect or may be amended from time to time in accordance with their terms and this Indenture, and authorizes and directs the Collateral Agent to enter into the Security Documents and to perform its obligations and exercise its rights thereunder in accordance therewith; provided, however, that if any of the provisions of the Security Documents limit, qualify or conflict with the duties imposed by the provisions of the TIA, the TIA shall control.

(b) To the extent required under the Second-Lien Notes Documents, the Issuer and the Subsidiary Guarantors shall execute any and all further documents, financing statements, agreements and instruments, and take all further action that may be required under applicable law, or that the Collateral Agent may reasonably request, in order to grant, preserve, protect and perfect the validity and priority of the security interests and Liens created or intended to be created by the Security Documents in the Collateral, including, without limitation, (i) prompt correction of any material defect which may hereafter be discovered in the title to the Mortgaged Property or in the execution and acknowledgment of the applicable Mortgage, any notes or any other document used in connection herewith or at any time delivered to Issuer or any Subsidiary Guarantor in connection with any indebtedness owing to the Second-Lien Creditors, and (ii) prompt execution and delivery of all division or transfer orders that in the reasonable discretion of the Collateral Agent are needed to transfer effectively the assigned proceeds of production from the Mortgaged Property to the Collateral Agent. In addition, to the extent required under the Second-Lien Notes Documents, from time to time, the Issuer will reasonably promptly secure the obligations under the Second-Lien Notes Documents by pledging or creating, or causing to be pledged or created, perfected security interests and Liens with respect to the Collateral perfected to the extent required by the Second-Lien Notes Documents. Such security interests and Liens will be created under the Security

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Documents and other security agreements and other instruments and documents in form and substance reasonably satisfactory to the Collateral Agent.

(1) in connection with the most recently completed Reserve Report delivered pursuant to Section 6.01 and 8.12 of the Senior Secured Credit Agreement (or any similar provision of agreements refinancing, replacing, refunding, amending, restating or supplementing the Senior Secured Credit Agreement as in effect on the Issue Date); or

(2) if no such provision exists, to certify in the form of an Officer’s Certificate to the Collateral Agent semi-annually on or before April 1 and October 1 (and at the time of any release permitted under the Senior Secured Credit Agreement, after giving effect thereto concurrently such Officer’s Certificate to such effect to the First Lien Collateral Agent)

that the Collateral includes Oil and Gas Properties subject to Mortgages over at least 80% of the total Recognized Value of the Issuer’s and the Subsidiary Guarantors’ proved Oil and Gas Properties located in the United States and adjacent Federal waters as reflected in the most recent available annual or semi-annual Reserve Report on such reserves (the “80% Requirement”) and that to the extent necessary, the Issuer and the Subsidiary Guarantors will cause to be delivered to the Collateral Agent (in form and substance reasonably satisfactory to the Collateral Agent) Mortgages or amendments or supplements to prior Mortgages to satisfy the 80% Requirement; to the extent that any Mortgages for Oil and Gas Properties constituting Collateral are released after the date of the applicable Reserve Report and prior to delivery of such Reserve Report or Officer’s Certificate, and are then assigned to Persons other than the Issuer and the Subsidiary Guarantors, any proved reserves attributable to such Oil and Gas Properties shall be deemed excluded from such Reserve Report for the purpose of determining whether the 80% Requirement is met after giving effect to such release.

SECTION 13.2. Recordings and Opinions.

(a) To the extent applicable, the Issuer will cause TIA § 313(b), relating to reports, to be complied with.

(b) Any release of Collateral permitted by Section 13.3 hereof will be deemed not to impair the Liens under this Indenture, the Notes, the Subsidiary Guarantees and the Security Documents in contravention thereof.

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SECTION 13.3. Release of Collateral.

Subject to Section 13.2 hereof, the Liens on the Collateral will be released, or subordinations of Liens on the Collateral will be granted, with respect to the Notes and the Subsidiary Guarantees, as applicable:

(1) in whole, upon payment in full of the principal of, accrued and unpaid interest, and premium, if any, on the Notes and payment in full of all other obligations under this Indenture, the Subsidiary Guarantees and the Security Documents that are due and payable at or prior to the time of such principal together with accrued and unpaid interest;

(2) in whole upon:

(a) satisfaction and discharge of this Indenture as set forth under Article VIII; or

(b) a Legal Defeasance or Covenant Defeasance of this Indenture under Article VIII;

(3) in part, as to any asset constituting Collateral (A) that is sold or otherwise disposed of by the Issuer or any of the Subsidiary Guarantors in a transaction permitted by the First-Lien Documents (whether or not an “event of default” under the First-Lien Documents or any Second-Lien Notes Documents has occurred and is continuing) if all other Liens on that asset securing the First-Lien Obligations (including all commitments thereunder) are released or (B) that is sold or otherwise disposed of by the Issuer or any Subsidiary Guarantor in accordance with, and as expressly provided for in, this Indenture, the Intercreditor Agreement and the Security Documents;

(4) in whole, as to the ATP Titan drilling and production platform and related assets, if such assets are contributed to an Infrastructure Subsidiary in connection with its designation as an Unrestricted Subsidiary in accordance with the definition thereof;

(5) as set forth under Article IX as to property that constitutes less than all or substantially all of the Collateral, with the consent of Holders of at least a majority in aggregate principal amount of the Notes then outstanding, voting as one class (or, in the case of a release of all or substantially all of the Collateral, with the consent of the Holders of at least 75% in aggregate principal amount of the Notes then outstanding, voting as one class), including consents obtained in connection with a tender offer or exchange offer for, or purchase of, the Notes; and

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(6) with respect to assets of a Subsidiary Guarantor upon release of such Subsidiary Guarantor from its Subsidiary Guarantee as set forth under Article XII.

On the date of Discharge of First-Lien Obligations, the Second-Priority Liens on the Collateral securing the Notes will not be released, except to the extent the Collateral or any portion thereof was disposed of in order to repay the First-Lien Obligations secured by the Collateral, and thereafter the Collateral Agent (or another designated representative acting at the direction of the Holders of a majority of outstanding principal amount of the Notes) will have the right (upon the occurrence of an Event of Default) to foreclose upon the Collateral (but in such event, the Liens on the Collateral securing the Notes will be released when such Event of Default and all other Events of Default under this Indenture cease to exist); provided, however, that if the Issuer or any Subsidiary Guarantor subsequently incurs First-Lien Obligations that are secured by Liens on property or assets of the Issuer or any Subsidiary Guarantor of the type constituting the Collateral and the related Liens are incurred in reliance on clause (1) of the definition of Permitted Liens, then the Issuer and the Subsidiary Guarantors will be required to reinstitute the security arrangements and Intercreditor Agreement with respect to the Collateral in favor of the Notes, which, in the case of any such subsequent First-Lien Obligations, will be Second-Priority Liens on the Collateral securing such First-Lien Obligations to the same extent provided by the Security Documents and Intercreditor Agreement and on the terms and conditions of the security documents relating to such First-Lien Obligations, with the Second-Priority Lien held either by the administrative agent, collateral agent or other representative for such First-Lien Obligations or by a collateral agent or other representative designated by the Issuer to hold the Second-Priority Liens for the benefit of the holders of the Notes and subject to an intercreditor agreement that provides the administrative agent or collateral agent substantially the same rights and powers as afforded under the Intercreditor Agreement.

In accordance with the Intercreditor Agreement and upon compliance by the Issuer or any Subsidiary Guarantor, as the case may be, with the conditions precedent required by this Indenture, the Trustee or the Collateral Agent shall promptly cause to be released and reconveyed to the Issuer, or the Subsidiary Guarantor, as the case may be, the released Collateral. Prior to each proposed release, the Issuer and each Subsidiary Guarantor shall furnish to the Trustee and the Collateral Agent all certificates, opinions and documents required by this Indenture, the Security Documents and the TIA.

SECTION 13.4. Maintenance of Collateral.

The Issuer shall, and shall cause each of the Subsidiary Guarantors to:

(1) maintain, develop and operate the interests being mortgaged in a good and workmanlike manner and observe and comply with all of the terms and provisions, of all oil and gas leases relating to the mortgaged interests so long as such oil

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and gas leases are capable of producing Hydrocarbons in paying quantities, except where such failure to comply would not have a material adverse effect;

(2) comply with all contracts and agreements applicable to or relating to the Mortgaged Property or the production and sale of Hydrocarbons therefrom, except to the extent a failure to so comply would not have a material adverse effect;

(3) maintain, preserve and keep all operating equipment used with respect to the Mortgaged Property in proper repair, working order and condition, and make all necessary or appropriate repairs, renewals, replacements, additions and improvements thereto so that the efficiency of such operating equipment shall at all times be properly preserved and maintained, except where such failure to comply would not have a material adverse effect;

(4) cause the Mortgaged Property to be kept free and clear of all Liens other than Permitted Liens;

(5) keep adequately insured by insurers of recognized responsibility, all of the Mortgaged Property of an insurable nature and of a character usually insured by Persons engaged in the same or similar business, against all risks customarily insured against by such Persons; and

(6) not sell, lease, transfer, abandon or otherwise dispose of any portion of the Mortgaged Property or any of Mortgagor’s rights, titles or interests therein or thereto, except as specifically permitted by this Indenture.

SECTION 13.5. Information Regarding Collateral.

(a) The Issuer shall promptly notify the Collateral Agent if any material portion of the Collateral is physically damaged, destroyed or condemned.

(b) Each year, within 120 days after the end of the preceding fiscal year, the Issuer shall deliver to the Trustee and the Collateral Agent a certificate of a responsible financial or accounting Officer setting forth the information required pursuant to the schedules required by the Security Documents or confirming that there has been no change in such information since the date of the prior annual financial statements.

(c) Any certificate or opinion required by Section 314(d) of the TIA may be made by an Officer of the Issuer, except in cases where Section 314(d) requires that such certificate or opinion be made by an independent engineer, appraiser or other expert.

(d) Notwithstanding anything to the contrary herein, the Issuer and its Subsidiaries will not be required to comply with all or any portion of Section 314(d) of the TIA if

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they determine, in good faith based on advice of counsel, that under the terms of that section and/or any interpretation or guidance as to the meaning thereof of the SEC and its staff, including “no action” letters or exemptive orders, all or any portion of Section 314(d) of the TIA is inapplicable to the released Collateral.

(e) Without limiting the generality of Section 13.5(c) above, certain no action letters issued by the SEC have permitted an indenture qualified under the TIA to contain provisions permitting the release of Collateral from Liens under such indenture in the ordinary course of the Issuer’s business without requiring the Issuer to provide certificates and other documents under Section 314(d) of the TIA. The Issuer and the Subsidiary Guarantors may, subject to the provisions of this Indenture without any release or consent by the Trustee, the Collateral Agent or First-Lien Collateral Agent, conduct ordinary course activities with respect to the Collateral, including, without limitation:

(1) selling or otherwise disposing of, in any transaction or series of related transactions, any property subject to the Lien of the Security Documents that has become worn out, defective, obsolete or not used or useful in the business;

(2) abandoning, terminating, canceling, releasing or making alterations in or substitutions of any leases or contracts subject to the Lien of the Indenture or any of the Security Documents;

(3) surrendering or modifying any franchise, license or permit subject to the Lien of the Security Documents that it may own or under which it may be operating;

(4) altering, repairing, replacing, changing the location or position of and adding to its structures, machinery, systems, equipment, fixtures and appurtenances;

(5) selling, transferring or otherwise disposing of inventory or accounts receivable in the ordinary course of business; and

(6) making cash payments (including for the repayment of Indebtedness or interest) from cash that is at any time part of the Collateral in the ordinary course of business that are not otherwise prohibited by this Indenture and the Security Documents.

SECTION 13.6. Suits to Protect the Collateral.

Subject to the provisions of Article VI hereof and the Security Documents, the Trustee in its sole discretion and without the consent of the Holders, on behalf of the Holders, may, and upon direction of a majority of Holders shall, direct the Collateral Agent to take all actions it deems necessary or appropriate in order to:

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(a) enforce any of the terms of the Security Documents; and

(b) collect and receive any and all amounts payable in respect of the obligations hereunder.

Subject to the provisions of the Security Documents, the Trustee shall have power to institute and to maintain such suits and proceedings as it may deem expedient to prevent any impairment of the Collateral by any acts which may be unlawful or in violation of any of the Security Documents or this Indenture, and such suits and proceedings as the Trustee, in its sole discretion, may deem expedient to preserve or protect its interests and the interests of the Holders in the Collateral (including power to institute and maintain suits or proceedings to restrain the enforcement of or compliance with any legislative or other governmental enactment, rule or order that may be unconstitutional or otherwise invalid if the enforcement of, or compliance with, such enactment, rule or order would impair the Lien on the Collateral or be prejudicial to the interests of the Holders or the Trustee). Nothing in this Section 13.6 shall be considered to impose any such duty or obligation to act on the part of the Trustee.

SECTION 13.7. Authorization of Receipt of Funds by the Trustee Under the Security Documents.

Subject to the provisions of an Intercreditor Agreement, the Trustee is authorized to receive any funds for the benefit of the Holders distributed under the Security Documents, and to make further distributions of such funds to the Holders according to the provisions of this Indenture.

SECTION 13.8. Purchase Protected.

In no event shall any purchaser in good faith of any property purported to be released hereunder be bound to ascertain the authority of the Collateral Agent or the Trustee to execute the release or to inquire as to the satisfaction of any conditions required by the provisions hereof for the exercise of such authority or to see to the application of any consideration given by such purchaser or other transferee; nor shall any purchaser or other transferee of any property or rights permitted by this Article XIII to be sold be under any obligation to ascertain or inquire into the authority of the Issuer or the applicable Subsidiary Guarantor to make any such sale or other transfer.

SECTION 13.9. Powers Exercisable by Receiver or Trustee.

In case the Collateral shall be in the possession of a receiver or trustee, lawfully appointed, the powers conferred in this Article XIII upon the Issuer or a Subsidiary Guarantor with respect to the release, sale or other disposition of such property may be exercised by such receiver or trustee, and an instrument signed by such receiver or trustee shall be

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deemed the equivalent of any similar instrument of the Issuer or a Subsidiary Guarantor or of any officer or officers thereof required by the provisions of this Article XIII; and if the Trustee shall be in the possession of the Collateral under any provision of this Indenture, then such powers may be exercised by the Trustee.

SECTION 13.10. Release upon Termination of the Issuer’s Obligations.

In the event that the Issuer delivers to the Trustee, in form and substance reasonably acceptable to it, an Officer’s Certificate certifying that (i) payment in full of the principal of, together with accrued and unpaid interest (including additional interest, if any) on, the Notes and all other Obligations under this Indenture, the Subsidiary Guarantees and the Security Documents that are due and payable at or prior to the time such principal, together with accrued and unpaid interest, are paid or (ii) the Issuer shall have exercised its Legal Defeasance option or its Covenant Defeasance option, in each case in compliance with the provisions of Article VIII, the Trustee shall deliver to the Issuer and the Collateral Agent a notice stating that the Trustee, on behalf of the Holders, disclaims and gives up any and all rights it has in or to the Collateral (other than with respect to funds held by the Trustee pursuant to Article XIII), and any rights it has under the Security Documents, and upon receipt by the Collateral Agent of such notice, the Collateral Agent shall be deemed not to hold a Lien in the Collateral on behalf of the Trustee and shall do or cause to be done all acts reasonably necessary to release such Lien as soon as is reasonably practicable.

SECTION 13.11. Collateral Agent.

(a) The Trustee and each of the Holders by acceptance of the Notes hereby designates and appoints the Collateral Agent as its agent under this Indenture and the Security Documents and the Trustee and each of the Holders by acceptance of the Notes hereby irrevocably authorizes the Collateral Agent to take such action on its behalf under the provisions of this Indenture and the Security Documents and to exercise such powers and perform such duties as are expressly delegated to the Collateral Agent by the terms of this Indenture and the Security Documents, together with such powers as are reasonably incidental thereto. The Collateral Agent agrees to act as such on the express conditions contained in this Section 13.11. The provisions of this Section 13.11 are solely for the benefit of the Collateral Agent and none of the Trustee, any of the Holders nor the Issuer or any of the Subsidiary Guarantors shall have any rights as a third party beneficiary of any of the provisions contained herein other than as expressly provided in Section 13.3. Notwithstanding any provision to the contrary contained elsewhere in this Indenture and the Security Documents, the Collateral Agent shall not have any duties or responsibilities, except those expressly set forth herein, nor shall the Collateral Agent have or be deemed to have any fiduciary relationship with the Trustee, any Holder or the Issuer or any Subsidiary Guarantor, and no implied covenants, functions, responsibilities, duties, obligations or liabilities shall be read into this Indenture and the Security Documents or otherwise exist against the Collateral Agent. Without limiting the generality of

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the foregoing sentence, the use of the term “agent” in this Indenture with reference to the Collateral Agent is not intended to connote any fiduciary or other implied (or express) obligations arising under agency doctrine of any applicable law. Instead, such term is used merely as a matter of market custom, and is intended to create or reflect only an administrative relationship between independent contracting parties. Except as expressly otherwise provided in this Indenture, the Collateral Agent shall have and may use its sole discretion with respect to exercising or refraining from exercising any discretionary rights or taking or refraining from taking any actions which the Collateral Agent is expressly entitled to take or assert under this Indenture and the Security Documents, including the exercise of remedies pursuant to Article VI, and any action so taken or not taken shall be deemed consented to by the Trustee and the Holders.

(b) The Collateral Agent may execute any of its duties under this Indenture or the Security Documents by or through agents, employees or attorneys-in-fact and shall be entitled to advice of counsel concerning all matters pertaining to such duties. The Collateral Agent shall not be responsible for the negligence or misconduct of any agent, employee or attorney-in-fact that it selects as long as such selection was made with due care.

(c) None of the Collateral Agent or any of its agents or employees shall (i) be liable for any action taken or omitted to be taken by any of them under or in connection with this Indenture or the transactions contemplated hereby (except for its own gross negligence or willful misconduct) or under or in connection with the any Security Document or the transactions contemplated thereby (except for its own gross negligence or willful misconduct), or (ii) be responsible in any manner to the Trustee or any Holder or any other Person for any recital, statement, representation, warranty, covenant or agreement made by the Issuer or any Subsidiary Guarantor, contained in this or any Indenture, or in any certificate, report, statement or other document referred to or provided for in, or received by the Collateral Agent under or in connection with, this or any other Indenture or the Security Documents, or the validity, effectiveness, genuineness, enforceability or sufficiency of this or any other Indenture or the Security Documents, or for any failure of the Issuer or any Subsidiary Guarantor or any other party to this Indenture or the Security Documents to perform its obligations hereunder or thereunder. None of the Collateral Agent or any of its agents or employees shall be under any obligation to the Trustee or any Holder or any other Person to ascertain or to inquire as to the observance or performance of any of the agreements contained in, or conditions of, this or any other Indenture or the Security Documents or to inspect the properties, books or records of the Issuer or any Subsidiary Guarantor.

(d) The Collateral Agent shall be entitled to rely, and shall be fully protected in relying, upon any writing, resolution, notice, consent, certificate, affidavit, letter, telegram, facsimile, telex or telephone message, statement or other document or conversation believed by it to be genuine and correct and to have been signed, sent or made by the proper Person or Persons, and upon advice and statements of legal counsel (including, without limita-

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tion, counsel to the Issuer or any Subsidiary Guarantor), independent accountants and other experts and advisors selected by the Collateral Agent. The Collateral Agent shall be fully justified in failing or refusing to take any action under this Indenture or any other indenture or the Security Documents unless it shall first receive such advice or concurrence of the Trustee as it deems appropriate and, if it so requests, it shall first be indemnified to its satisfaction by the Holders or the applicable authorized representative against any and all liability and expense which may be incurred by it by reason of taking or continuing to take any such action. The Collateral Agent shall in all cases be fully protected in acting, or in refraining from acting, under this Indenture or any other indenture or the Security Documents in accordance with a request or consent of the Trustee or the applicable authorized representative and such request and any action taken or failure to act pursuant thereto shall be binding upon all of the Holders or any other Person.

(e) The Collateral Agent shall not be deemed to have knowledge or notice of the occurrence of any Default or Event of Default, unless the Collateral Agent shall have received written notice from the Trustee or the Issuer referring to this Indenture, describing such Default or Event of Default and stating that such notice is a “notice of default.” The Collateral Agent shall take such action with respect to such Default or Event of Default as may be requested by the Trustee in accordance with Article VI (subject to this Section 13.11); provided, however, that unless and until the Collateral Agent has received any such request, the Collateral Agent may (but shall not be obligated to) take such action, or refrain from taking such action, with respect to such Default or Event of Default as it shall deem advisable.

(f) The Bank of New York Mellon Trust Company, N.A. and its Affiliates (and any successor Collateral Agent and its Affiliates) may make loans to, issue letters of credit for the account of, accept deposits from, acquire equity interests in and generally engage in any kind of banking, trust, financial advisory, underwriting, or other business with the Issuer and the Subsidiary Guarantors as though it was not the Collateral Agent hereunder and without notice to or consent of the Trustee. The Trustee and the Holders acknowledge that, pursuant to such activities, the Bank of New York Mellon Trust Company, N.A. or its Affiliates (and any successor Collateral Agent and its Affiliates) may receive information regarding the Issuer and the Subsidiary Guarantors (including information that may be subject to confidentiality obligations in favor of the Issuer and the Subsidiary Guarantors) and acknowledge that the Collateral Agent shall not be under any obligation to provide such information to the Trustee or the Holders. Nothing herein shall impose or imply any obligation on the part of the Bank of New York Mellon Trust Company, N.A. (or any successor Collateral Agent) to advance funds.

(g) The Collateral Agent may resign at any time upon thirty (30) days prior written notice to the Trustee and the Issuer, such resignation to be effective upon the acceptance of a successor agent to its appointment as Collateral Agent. If the Collateral Agent resigns under this Indenture, the Trustee, subject to the consent of the Issuer (which shall not be

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unreasonably withheld and which shall not be required during a continuing Event of Default), shall appoint a successor Collateral Agent. If no successor collateral agent is appointed prior to the intended effective date of the resignation of the Collateral Agent (as stated in the notice of resignation), the Collateral Agent may appoint, after consulting with the Trustee, subject to the consent of the Issuer (which shall not be unreasonably withheld and which shall not be required during a continuing Event of Default), a successor collateral agent. If no successor collateral agent is appointed and consented to by the Issuer pursuant to the preceding sentence within thirty (30) days after the intended effective date of resignation (as stated in the notice of resignation) the Collateral Agent shall be entitled to petition at the expense of the Issuer a court of competent jurisdiction to appoint a successor. Upon the acceptance of its appointment as successor collateral agent hereunder, such successor collateral agent shall succeed to all the rights, powers and duties of the retiring Collateral Agent, and the term “Collateral Agent” shall mean such successor collateral agent, and the retiring Collateral Agent’s appointment, powers and duties as the Collateral Agent shall be terminated. After the retiring Collateral Agent’s resignation hereunder, the provisions of this Section 13.11 (and Section 13.12) shall continue to inure to its benefit and the retiring Collateral Agent shall not by reason of such resignation be deemed to be released from liability as to any actions taken or omitted to be taken by it while it was the Collateral Agent under this Indenture.

(h) The Trustee shall initially act as Collateral Agent and shall be authorized to appoint co-Collateral Agents as necessary in its sole discretion. Except as otherwise explicitly provided herein or in the Security Documents, neither the Collateral Agent nor any of its officers, directors, employees or agents shall be liable for failure to demand, collect or realize upon any of the Collateral or for any delay in doing so or shall be under any obligation to sell or otherwise dispose of any Collateral upon the request of any other Person or to take any other action whatsoever with regard to the Collateral or any part thereof. The Collateral Agent shall be accountable only for amounts that it actually receives as a result of the exercise of such powers, and neither the Collateral Agent nor any of its officers, directors, employees or agents shall be responsible for any act or failure to act hereunder, except for its own willful misconduct, gross negligence or bad faith.

(i) The Trustee, as such and as Collateral Agent, is authorized and directed to (A) enter into the Security Documents, (B) enter into the Intercreditor Agreement, (C) bind the Holders on the terms as set forth in the Security Documents and the Intercreditor Agreement and (D) perform and observe its obligations under the Security Documents and the Intercreditor Agreement.

(j) The Trustee agrees that it shall not (and shall not be obliged to), and shall not instruct the Collateral Agent to, unless specifically requested to do so by a majority of the Holders, take or cause to be taken any action to enforce its rights under this Indenture or against the Issuer and the Subsidiary Guarantors, including the commencement of any legal

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or equitable proceedings, to foreclose any Lien on, or otherwise enforce any security interest in, any of the Collateral.

(k) If at any time or times the Trustee shall receive (i) by payment, foreclosure, set-off or otherwise, any proceeds of Collateral or any payments with respect to the Obligations arising under, or relating to, this Indenture, except for any such proceeds or payments received by the Trustee from the Collateral Agent pursuant to the terms of this Indenture, or (ii) payments from the Collateral Agent in excess of the amount required to be paid to the Trustee pursuant to Article VI, the Trustee shall promptly turn the same over to the Collateral Agent, in kind, and with such endorsements as may be required to negotiate the same to the Collateral Agent.

(l) Should the Trustee obtain possession of any such Collateral, upon request from the Issuer, the Trustee shall notify the Collateral Agent thereof, and, promptly upon the Collateral Agent’s request therefor, shall deliver such Collateral to the Collateral Agent or otherwise deal with such Collateral in accordance with the Collateral Agent’s instructions.

(m) The Collateral Agent shall have no obligation whatsoever to the Trustee or any of the Holders or any other Person to assure that the Collateral exists or is owned by the Issuer and the Subsidiary Guarantors or is cared for, protected or insured or has been encumbered, or that the Collateral Agent’s Liens have been properly or sufficiently or lawfully created, perfected, protected, maintained or enforced or are entitled to any particular priority, or to determine whether all of the Grantor’s property constituting collateral intended to be subject to the Lien and security interest of the Security Documents has been properly and completely listed or delivered, as the case may be, or the genuineness, validity, marketability or sufficiency thereof or title thereto, or to exercise at all or in any particular manner or under any duty of care, disclosure or fidelity, or to continue exercising, any of the rights, authorities and powers granted or available to the Collateral Agent pursuant to this Indenture or any Security Document, it being understood and agreed that in respect of the Collateral, or any act, omission or event related thereto, the Collateral Agent may act in any manner it may deem appropriate, in its sole discretion given the Collateral Agent’s own interest in the Collateral, and that the Collateral Agent shall have no other duty or liability whatsoever to the Trustee or any Holder or any other Person as to any of the foregoing.

(n) No provision of this Indenture or any Security Document shall require the Collateral Agent (or the Trustee) to expend or risk its own funds or otherwise incur any financial liability in the performance of any of its duties hereunder or thereunder or to take or omit to take any action hereunder or thereunder or take any action at the request or direction of Holders (or the Trustee in the case of the Collateral Agent).

(o) The Collateral Agent (i) shall not be liable for any action it takes or omits to take in good faith which it reasonably believes to be authorized or within its rights or

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powers, or for any error of judgment made in good faith by a Trust Officer, unless it is proved that the Collateral Agent was grossly negligent in ascertaining the pertinent facts, (ii) shall not be liable for interest on any money received by it except as the Collateral Agent may agree in writing with the Issuer (and money held in trust by the Collateral Agent need not be segregated from other funds except to the extent required by law), and (iii) may consult with counsel of its selection and the advice or opinion of such counsel as to matters of law shall be full and complete authorization and protection from liability in respect of any action taken, omitted or suffered by it in good faith and in accordance with the advice or opinion of such counsel. The grant of permissive rights or powers to the Collateral Agent shall not be construed to impose duties to act.

(p) Notwithstanding anything to the contrary herein, the obligations of the Issuer and Subsidiary Guarantors owing to the Collateral Agent shall remain in full force and effect and all of the Collateral Agent’s rights, protections, indemnities and immunities granted hereunder shall survive the satisfaction and discharge of the Indenture so long as any Mortgage to which the Collateral Agent is a party remains effective and outstanding.

SECTION 13.12. Compensation and Indemnification.

The Collateral Agent shall be entitled to the compensation, reimbursement of expenses, disbursements and advances, and indemnification set forth in Section 7.7 (with the references to the Trustee therein being deemed to refer to the Collateral Agent).

SECTION 13.13. Security Documents; Intercreditor Agreement; Other Security Documents.

(a) The Trustee and the Collateral Agent is each hereby directed and authorized to execute and deliver the Intercreditor Agreement, Mortgages, the Pledge Agreements and the other Security Documents in which it is named as a party. It is hereby expressly acknowledged and agreed that, in doing so, the Trustee and the Collateral Agent are not responsible for the terms or contents of such agreements, or for the validity or enforceability thereof, or the sufficiency thereof for any purpose. Whether or not so expressly stated therein, in entering into, or taking (or forbearing from) any action under or pursuant to, the Intercreditor Agreement, the Mortgages, the Pledge Agreements or any other Security Documents, the Trustee and Collateral Agent each shall have all of the rights, immunities, indemnities and other protections granted to it under this Indenture (in addition to those that may be granted to it under the terms of such other agreement or agreements).

(b) The security interests securing the Notes and the Subsidiary Guarantees will be, pursuant to the Intercreditor Agreement, second in priority to any and all security interests ay any time granted to secure the First-Lien Obligations and will also be subject to all other Permitted Liens. The Intercreditor defines the relative rights of holders of Second-Priority Liens and holders of First-Priority Liens.

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ARTICLE XIV.

RANKING OF LIENS

SECTION 14.1. Relative Rights.

Nothing in this Indenture will:

(a) impair, as between the Issuer and Holders, the obligation of the Issuer, which is absolute and unconditional, to pay principal of, premium and interest on such Notes in accordance with their terms or to perform any other obligation of the Issuer or any Subsidiary Guarantor under this Indenture, the Notes, the Subsidiary Guarantees and the Security Documents;

(b) restrict the right of any Holder to ▇▇▇ for payments that are then due and owing, in a manner not inconsistent with the provisions of the Intercreditor Agreement;

(c) prevent the Trustee or any Holder from exercising against the Issuer or any Subsidiary Guarantor any of its other available remedies upon a Default or Event of Default; or

(d) restrict the right of the Trustee or any Holder:

(i) to file and prosecute a petition seeking an order for relief in an involuntary bankruptcy case as to the Issuer or any Subsidiary Guarantor or otherwise to commence, or seek relief commencing, any Insolvency or Liquidation Proceeding involuntarily against the Issuer or any Subsidiary Guarantor;

(ii) to make, support or oppose any request for an order for dismissal, abstention or conversion in any Insolvency or Liquidation Proceeding;

(iii) to make, support or oppose, in any Insolvency or Liquidation Proceeding, any request for an order extending or terminating any period during which the debtor (or any other Person) has the exclusive right to propose a plan of reorganization or other dispositive restructuring or liquidation plan therein;

(iv) to seek the creation of, or appointment to, any official committee representing creditors (or certain of the creditors) in any Insolvency or Liquidation Proceeding and, if appointed, to serve and act as a member of such committee without being in any respect restricted or bound by, or liable for, any of the obligations under this Article Fourteen;

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(v) to seek or object to the appointment of any professional person to serve in any capacity in any Insolvency or Liquidation Proceeding or to support or object to any request for compensation made by any professional person or others therein;

(vi) to make, support or oppose any request for an order appointing a trustee or examiner in any Insolvency or Liquidation Proceeding; or

(vii) otherwise to make, support or oppose any request for relief in any Insolvency or Liquidation Proceeding that it is permitted by law to make, support or oppose:

(a) as if it were a holder of unsecured claims; or

(b) as to any matter relating to any plan of reorganization or other restructuring or liquidation plan or as to any matter relating to the administration of the estate or the disposition of the case or proceeding (in each case set forth in this clause (vii) except as set forth in the Intercreditor Agreement).

[Signature Pages Follow]

SIGNATURES

IN WITNESS WHEREOF, the parties hereto have caused this Indenture to be duly executed, all as of the date first written above.


ATP OIL & GAS CORPORATION

By:	/s/ ▇▇▇▇▇▇ ▇. ▇▇▇▇
	Name:	▇▇▇▇▇▇ ▇. ▇▇▇▇
	Title:	President

[Indenture]

S-1


THE BANK OF NEW YORK MELON TRUST COMPANY, N.A., as Trustee and Collateral Agent

By:	/s/ ▇▇▇▇▇ ▇▇▇▇▇▇▇-▇▇▇▇▇
	Name:	▇▇▇▇▇ ▇▇▇▇▇▇▇-▇▇▇▇▇
	Title:	Senior Associate

[Indenture]

EXHIBIT A

[Insert the Global Note Legend, if applicable pursuant to the provisions of the Indenture]

[Insert the Private Placement Legend, if applicable pursuant to the provisions of the Indenture]

CUSIP / ISIN No.: [ ]

ATP OIL & GAS CORPORATION

11.875% SENIOR SECOND LIEN NOTE DUE 2015


No. [ ]		$[ ]

ATP OIL & GAS CORPORATION, a Texas corporation (the “Issuer,” which term includes any successor entities), for value received promises to pay to CEDE & CO. or registered assigns the principal sum of [ ] Dollars (or such greater or lesser amount as may be indicated on Schedule A hereto) on May 1, 2015.

Interest Payment Dates: May 1 and November 1, commencing November 1, 2010.

Record Dates: April 15 and October 15.

Reference is made to the further provisions of this Note contained herein, which will for all purposes have the same effect as if set forth at this place.

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IN WITNESS WHEREOF, the Issuer has caused this Note to be signed manually or by facsimile by its duly authorized officers and a facsimile of its corporate seal to be affixed hereto or imprinted hereon.


ATP OIL & GAS CORPORATION

By:
		Name:
		Title:

Dated:

Certificate of Authentication

This is one of the 11.875% Senior Second Lien Notes due 2015 referred to in the within-mentioned Indenture.


THE BANK OF NEW YORK MELON TRUST COMPANY, N.A., as Trustee and Collateral Agent

By:
		Authorized Signatory

Date of Authentication:

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(REVERSE OF SECURITY)

11.875% Senior Second Lien Note due 2015

(1) Interest. ATP OIL & GAS CORPORATION (the “Issuer”) promises to pay interest on the principal amount of this Note at the rate per annum shown above, including any Liquidated Damages, if any, payable in the form of additional interest pursuant to Section 2(d) of the Registration Rights Agreement referred to below. Interest on the Notes will accrue from the most recent date on which interest has been paid or, if no interest has been paid, from April 23, 2010. The Issuer will pay interest semi-annually in arrears on each Interest Payment Date, commencing November 1, 2010. Interest will be computed on the basis of a 360-day year of twelve 30-day months and, in the case of a partial month, the actual number of days elapsed.

(2) Method of Payment. The Issuer shall pay interest on the Notes to the Persons who are the registered Holders at the close of business on the Record Date immediately preceding the Interest Payment Date even if the Notes are canceled on registration of transfer or registration of exchange after such Record Date. Holders must surrender Notes to a Paying Agent to collect principal payments. The Issuer shall pay principal, premium and interest in money of the United States that at the time of payment is legal tender for payment of public and private debts (“U.S. Legal Tender”). The Issuer may deliver any such interest payment to the Paying Agent or to a Holder at the Holder’s registered address.

(3) Paying Agent and Registrar. Initially, The Bank of New York Melon Trust Company, N.A. (the “Trustee”) will act as Paying Agent and Registrar. The Issuer may change any Paying Agent, Registrar or co-Registrar without notice to the Holders.

(4) Indenture. The Issuer issued the Notes under an Indenture, dated as of April 23, 2010 (the “Indenture”), among the Issuer, the Trustee and the Collateral Agent. This Note is one of a duly authorized issue of Notes of the Issuer designated as its 11.875% Senior Second Lien Notes due 2015 (the “Notes”). The Notes include any Additional Notes. The Notes and any Additional Notes are treated as a single class of securities under the Indenture. Capitalized terms herein are used as defined in the Indenture unless otherwise defined herein. The terms of the Notes include those stated in the Indenture and those made part of the Indenture by reference to the Trust Indenture Act of 1939 (15 U.S. Code §§ 77aaa-77bbbb) (the “TIA”), as in effect on the date of the Indenture. Notwithstanding anything to the contrary herein, the Notes are subject to all such terms, and Holders of Notes are referred to the Indenture and the TIA for a statement of them. The Notes are general secured obligations of the Issuer. Payment on each Note is guaranteed on a senior basis by the Subsidiary Guarantors pursuant to Article 12 of the Indenture. Each Holder, by accepting a Note, agrees to be bound by all of the terms and provisions of the Indenture, as the same may be amended from time to time in accordance with its terms.

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(5) Redemption. (a) Except as set forth in Sections 3.3(b) and (c) of the Indenture, the Issuer will not be entitled to redeem the Notes at its option prior to May 1, 2013. The Notes will be redeemable, at the Issuer’s option, in whole at any time or in part from time to time, on and after May 1, 2013, at the following Redemption Prices (expressed as percentages of the principal amount thereof) if redeemed during the twelve-month period commencing on May 1 of the years set forth below, plus, in each case, accrued and unpaid interest thereon to the date of redemption:


Year	Percentage
2013	111.875	%
2014	100.000	%

(b) At any time, or from time to time, prior to May 1, 2013, the Issuer may, at its option, use all or a portion of the Net Cash Proceeds of one or more Equity Offerings to redeem up to 35% of the aggregate principal amount of the Notes (including any Additional Notes) issued under the Indenture at a Redemption Price equal to 111.875% of the aggregate principal amount of the Notes to be redeemed, plus accrued and unpaid interest thereon to the date of redemption; provided that: (1) at least 65% of the aggregate principal amount of Notes issued under the Indenture on the Issue Date remains outstanding immediately after giving effect to any such redemption; and (2) the Issuer makes such redemption not more than 90 days after the consummation of any such Equity Offering.

(c) In addition, the Notes may be redeemed, in whole or in part, at any time prior to May 1, 2013 at the option of the Issuer at a Redemption Price equal to 100% of the principal amount of the Notes redeemed plus the Applicable Premium as of, and accrued and unpaid interest to, the applicable redemption date (subject to the right of holders of record on the relevant record date to receive interest due on the relevant interest payment date).

(6) Notice of Redemption. Notice of redemption will be mailed at least 30 days but not more than 60 days before the Redemption Date to each Holder of Notes to be redeemed at such Holder’s registered address. Notes in denominations larger than $2,000 may be redeemed in part.

Except as set forth in the Indenture, if monies for the redemption of the Notes called for redemption shall have been deposited with the Paying Agent for redemption on such Redemption Date, then, unless the Issuer defaults in the payment of such Redemption Price plus accrued interest the Notes called for redemption will cease to bear interest from and after such Redemption Date and the only right of the Holders of such Notes will be to receive payment of the Redemption Price plus accrued interest.

(7) Offers to Purchase. Sections 4.15 and 4.16 of the Indenture provide that, upon the occurrence of a Change of Control (as defined in the Indenture) and after certain Asset Dispositions (as defined in the Indenture), and subject to further limitations con-

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tained therein, the Issuer will make an offer to purchase certain amounts of the Notes in accordance with the procedures set forth in the Indenture.

(8) Denominations; Transfer; Exchange. The Notes are in registered form, without coupons, and in denominations of at least $2,000 and integral multiples of $1,000 thereafter. A Holder shall register the transfer of or exchange Notes in accordance with the Indenture. The Registrar may require a Holder, among other things, to furnish appropriate endorsements and transfer documents and to pay certain transfer taxes or similar governmental charges payable in connection therewith as permitted by the Indenture. The Registrar need not register the transfer of or exchange of any Notes or portions thereof selected for redemption.

(9) Persons Deemed Owners. The registered Holder of a Note shall be treated as the owner of it for all purposes.

(10) Unclaimed Money. If money for the payment of principal or interest remains unclaimed for one year, the Trustee and the Paying Agent will pay the money back to the Issuer. After that, all liability of the Trustee and such Paying Agent with respect to such money shall cease.

(11) Discharge Prior to Redemption or Maturity. If the Issuer at any time deposits with the Trustee U.S. Legal Tender or U.S. Government Obligations sufficient to pay the principal of and interest on the Notes to redemption or maturity and comply with the other provisions of the Indenture relating thereto, the Issuer will be discharged from certain provisions of the Indenture and the Notes (including certain covenants, but including, under certain circumstances, its obligation to pay the principal of and interest on the Notes but without affecting the rights of the Holders to receive such amounts from such deposits).

(12) Amendment; Supplement; Waiver. Subject to certain exceptions set forth in the Indenture, the Indenture or the Notes or the Subsidiary Guarantees may be amended or supplemented with the written consent of the Holders of not less than a majority in aggregate principal amount of the Notes then outstanding, and any past Default or Event of Default or noncompliance with any provision may be waived with the written consent of the Holders of not less than a majority in aggregate principal amount of the Notes then outstanding. Without notice to or consent of any Holder, the parties thereto may amend or supplement the Indenture or the Notes to, among other things, cure any ambiguity, defect or inconsistency, provide for uncertificated Notes in addition to or in place of certificated Notes, comply with any requirements of the SEC in order to effect or maintain the qualification of the Indenture under the TIA or comply with Article V of the Indenture or make any other change that does not adversely affect the rights of any Holder of a Note.

(13) Restrictive Covenants. The Indenture imposes certain limitations on the ability of the Issuer and its Restricted Subsidiaries to, among other things, incur additional Indebtedness, make payments in respect of their Capital Stock or certain Indebtedness, make

A-5

certain Investments, create or incur liens, enter into transactions with Affiliates, create dividend or other payment restrictions affecting Restricted Subsidiaries, issue Preferred Stock of their Restricted Subsidiaries, and on the ability of the Issuer and its Restricted Subsidiaries to merge or consolidate with any other Person or sell, assign, transfer, lease, convey or otherwise dispose of all or substantially all of the Issuer’s and its Restricted Subsidiaries’ assets or adopt a plan of liquidation. Such limitations are subject to a number of important qualifications and exceptions. Pursuant to Section 4.6 of the Indenture, the Issuer must annually report to the Trustee on compliance with such limitations.

(14) Successors. When a successor assumes, in accordance with the Indenture, all the obligations of its predecessor under the Notes and the Indenture, the predecessor, subject to certain exceptions, will be released from those obligations.

(15) Defaults and Remedies. Except as set forth in the Indenture, if an Event of Default occurs and is continuing, the Trustee or the Holders of not less than 25% in principal amount of Notes then outstanding may declare all the Notes to be due and payable in the manner, at the time and with the effect provided in the Indenture. Holders of Notes may not enforce the Indenture or the Notes except as provided in the Indenture. The Trustee is not obligated to enforce the Indenture or the Notes unless it has received indemnity or security satisfactory to it. The Indenture permits, subject to certain limitations therein provided, Holders of a majority in aggregate principal amount of the Notes then outstanding to direct the Trustee in its exercise of any trust or power. The Trustee may withhold from Holders of Notes notice of any continuing Default or Event of Default (except a Default in payment of principal, premium or interest when due, for any reason or a Default in compliance with Article V of the Indenture) if it determines that withholding notice is in their interest.

(16) Trustee Dealings with Issuer. The Trustee under the Indenture, in its individual or any other capacity, may become the owner or pledgee of Notes and may otherwise deal with the Issuer, its respective Subsidiaries or its respective Affiliates as if it were not the Trustee.

(17) No Recourse Against Others. No partner, director, officer, employee or stockholder, as such, of the Issuer or any Subsidiary Guarantor, as such, shall have any liability for any obligations of the Issuer or any Subsidiary Guarantor under the Notes, the Indenture or the Subsidiary Guarantees or for any claim based on, in respect of, or by reason of, such obligations or their creation. Each Holder of Notes by accepting a Note waives and releases all such liability. The waiver and release are part of the consideration for the issuance of the Notes.

(18) Subsidiary Guarantees. This Note will be entitled to the benefits of certain Subsidiary Guarantees, if any, made for the benefit of the Holders. Reference is hereby made to the Indenture for a statement of the respective rights, limitations of rights, duties and obligations thereunder of the Subsidiary Guarantors, the Trustee and the Holders.

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(19) Authentication. This Note shall not be valid until the Trustee or Authenticating Agent manually signs the certificate of authentication on this Note.

(20) Governing Law. This Note and the Indenture shall be governed by and construed in accordance with the laws of the State of New York. Each of the parties hereto agrees to submit to the jurisdiction of the courts of the State of New York in any action or proceeding arising out of or relating to this Note.

(21) Abbreviations and Defined Terms. Customary abbreviations may be used in the name of a Holder of a Note or an assignee, such as: TEN COM (= tenants in common), TEN ENT (= tenants by the entireties), JT TEN (= joint tenants with right of survivorship and not as tenants in common), CUST (= Custodian), and U/G/M/A (= Uniform Gifts to Minors Act).

(22) Additional Rights Of Holders. In addition to the rights provided to Holders of Notes under the Indenture, Holders of this Note will have all the rights set forth in the Registration Rights Agreement dated as of April 23, 2010, among the Issuer and the other parties named on the signature pages thereof or, in the case of Additional Notes, Holders thereof will have the rights set forth in one or more registration rights agreements, if any, among the Issuer and the other parties thereto, relating to rights given by the Issuer to the purchasers of any Additional Notes (collectively, the “Registration Rights Agreement”).

(22) CUSIP Numbers. Pursuant to a recommendation promulgated by the Committee on Uniform Security Identification Procedures, the Issuer has caused CUSIP numbers to be printed on the Notes as a convenience to the Holders of the Notes. No representation is made as to the accuracy of such numbers as printed on the Notes and reliance may be placed only on the other identification numbers printed hereon.

The Issuer will furnish to any Holder of a Note upon written request and without charge a copy of the Indenture, which has the text of this Note, and/or the Registration Rights Agreement. Requests may be made to: ATP Oil & Gas Corporation, ▇▇▇▇ ▇▇▇▇ ▇▇▇ ▇▇▇▇▇, ▇▇▇▇▇ ▇▇▇, ▇▇▇▇▇▇▇, ▇▇ ▇▇▇▇▇.

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ASSIGNMENT FORM

If you the Holder want to assign this Note, fill in the form below and have your signature guaranteed:

I or we assign and transfer this Note to:

(Print or type name, address and zip code and

social security or tax ID number of assignee)

and irrevocably appoint , agent to transfer this Note on the books of the Issuer. The agent may substitute another to act for him.



Dated:	Signed:
		(Sign exactly as your name appears on the other side of this Note)

Signature Guarantee:

In connection with any transfer of this Note occurring prior to the date which is the earlier of (i) the date of the declaration by the SEC of the effectiveness of a registration statement under the Securities Act of 1933, as amended (the “Securities Act”) covering resales of this Note (which effectiveness shall not have been suspended or terminated at the date of the transfer) and (ii) October 23, 2010, the undersigned confirms that it has not utilized any general solicitation or general advertising in connection with the transfer:

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[Check One]

(1)

¨ to the Issuer or a subsidiary thereof; or

(2)

¨ pursuant to and in compliance with Rule 144A under the Securities Act of 1933, as amended; or

(3)

¨ outside the United states to a “foreign person” in compliance with Rule 904 of Regulation S under the Securities Act of 1933, as amended; or

(4)

¨ pursuant to the exemption from registration provided by Rule 144 under the Securities Act of 1933, as amended; or

(5)

¨ pursuant to an effective registration statement under the Securities Act of 1933, as amended; or

(6)

¨ pursuant to another available exemption from the registration requirements of the Securities Act of 1933, as amended.

and unless the box below is checked, the undersigned confirms that such Note is not being transferred to an “affiliate” of the Issuer as defined in Rule 144 under the Securities Act of 1933, as amended (an “Affiliate”):

The transferee is an Affiliate of the Issuer.

Unless one of the items is checked, the Trustee will refuse to register any of the Notes evidenced by this certificate in the name of any person other than the registered Holder thereof unless and until the conditions to any such transfer of registration set forth herein and in Section 2.6 of the Indenture shall have been satisfied; provided, however, that if item (4), (5) or (6) is checked, the Issuer may require, prior to registering any such transfer of the Notes, in its sole discretion, such written legal opinions, certifications (including an investment letter in the case of box (4)) and other information the Issuer has reasonably requested to confirm that such transfer is being made pursuant to an exemption from, or in a transaction not subject to, the registration requirements of the Securities Act of 1933, as amended.



Dated:	Signed:
		(Sign exactly as your name appears on the other side of this Note)

Signature Guarantee:

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TO BE COMPLETED BY PURCHASER IF (2) ABOVE IS CHECKED

The undersigned represents and warrants that it is purchasing this Note for its own account or an account with respect to which it exercises sole investment discretion and that it and any such account is a “qualified institutional buyer” within the meaning of Rule 144A under the Securities Act of 1933, as amended and is aware that the sale to it is being made in reliance on Rule 144A and acknowledges that it has received such information regarding the Issuer as the undersigned has requested pursuant to Rule 144A or has determined not to request such information and that it is aware that the transferor is relying upon the undersigned’s foregoing representations in order to claim the exemption from registration provided by Rule 144A.



Dated:
								NOTICE: To be executed by an executive officer

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[OPTION OF HOLDER TO ELECT PURCHASE]

If you want to elect to have this Note purchased by the Issuer pursuant to Section 4.15 or Section 4.16 of the Indenture, check the appropriate box:

Section 4.15 [ ] Change of Control Offer

Section 4.16 [ ] Limitation on Sales of Assets and Subsidiary Stock

If you want to elect to have only part of this Note purchased by the Issuer pursuant to Section 4.15 or Section 4.16 of the Indenture, state the amount you elect to have purchased:



Dated:
								NOTICE: The signature on this assignment must correspond with the name as it appears upon the face of the within Note in every particular without alteration or enlargement or any change whatsoever and be guaranteed.

Signature Guarantee:

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SCHEDULE A

SCHEDULE OF EXCHANGES OF INTERESTS IN GLOBAL NOTE*

The following exchanges of a part of this Global Note for an interest in another Global Note, or exchanges of a part of another Global Note for an interest in this Global Note, have been made:


Date of Exchange	Amount of decrease in Principal Amount of this Global Note	Amount of increase in Principal Amount of this Global Note	Principal Amount of this Global Note following such decrease (or increase)	Signature of authorized signatory of Trustee

*	Insert in Global Notes only.

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EXHIBIT B

Form of Certificate of Transfer

[ ], [ ]

The Bank of New York Melon Trust Company, N.A.

▇▇▇ ▇▇▇▇▇▇ ▇▇▇▇▇▇

▇▇▇▇ ▇▇▇▇▇

▇▇▇▇▇▇▇, ▇▇▇▇▇ ▇▇▇▇▇

Attn: Corporate Trust Administration,

re: ATP Oil & Gas Corp.

Ladies and Gentlemen:

Reference is hereby made to the Indenture, dated as of April 23, 2010 (the “Indenture”), among the Issuer, the Trustee and the Collateral Agent. Capitalized terms used but not defined herein shall have the meanings given to them in the Indenture.

(the “Transferor”) owns and proposes to transfer the Note[s] or interest in such Note[s] specified in Annex A hereto, in the principal amount of $ in such Note[s] or interests (the “Transfer”), to (the “Transferee”), as further specified in Annex A hereto. In connection with the Transfer, the Transferor hereby certifies that:

[CHECK ALL THAT APPLY]

1. ¨ CHECK IF TRANSFEREE WILL TAKE DELIVERY OF A BENEFICIAL INTEREST IN THE 144A GLOBAL NOTE OR A DEFINITIVE NOTE PURSUANT TO RULE 144A. The Transfer is being effected pursuant to and in accordance with Rule 144A under the United States Securities Act of 1933, as amended (the “Securities Act”), and, accordingly, the Transferor hereby further certifies that the beneficial interest or Definitive Note is being transferred to a Person that the Transferor reasonably believes is purchasing the beneficial interest or Definitive Note for its own account, or for one or more accounts with respect to which such Person exercises sole investment discretion, and such Person and each such account is a “qualified institutional buyer” within the meaning of Rule 144A in a transaction meeting the requirements of Rule 144A and such Transfer is in compliance with any applicable blue sky securities laws of any state of the United States.

2. ¨ CHECK IF TRANSFEREE WILL TAKE DELIVERY OF A BENEFICIAL INTEREST IN THE REGULATION S GLOBAL NOTE OR A DEFINITIVE NOTE PURSUANT TO REGULATION S. The Transfer is being effected pursuant to and in accor-

B-1

dance with Rule 903 or Rule 904 under the Securities Act and, accordingly, the Transferor hereby further certifies that (i) the Transfer is not being made to a person in the United States and (x) at the time the buy order was originated, the Transferee was outside the United States or such Transferor and any Person acting on its behalf reasonably believed and believes that the Transferee was outside the United States or (y) the transaction was executed in, on or through the facilities of a designated offshore securities market and neither such Transferor nor any Person acting on its behalf knows that the transaction was prearranged with a buyer in the United States, (ii) no directed selling efforts have been made in contravention of the requirements of Rule 903(b) or Rule 904(b) of Regulation S under the Securities Act (iii) the transaction is not part of a plan or scheme to evade the registration requirements of the Securities Act and (iv) if the proposed transfer is being made prior to the expiration of the Restricted Period, the transfer is not being made to a U.S. Person or for the account or benefit of a U.S. Person (other than an Initial Purchaser). Upon consummation of the proposed transfer in accordance with the terms of the Indenture, the transferred beneficial interest or Definitive Note will be subject to the restrictions on Transfer enumerated in the Indenture and the Securities Act.

3. ¨ CHECK AND COMPLETE IF TRANSFEREE WILL TAKE DELIVERY OF A BENEFICIAL INTEREST IN THE DEFINITIVE NOTE PURSUANT TO ANY PROVISION OF THE SECURITIES ACT OTHER THAN RULE 144A OR REGULATION S. The Transfer is being effected in compliance with the transfer restrictions applicable to beneficial interests in Restricted Global Notes and Restricted Definitive Notes and pursuant to and in accordance with the Securities Act and any applicable blue sky securities laws of any state of the United States, and accordingly the Transferor hereby further certifies that (check one):

(a) ¨ such Transfer is being effected pursuant to and in accordance with Rule 144 under the Securities Act;

(b) ¨ such Transfer is being effected to the Issuer or a subsidiary thereof;

(c) ¨ such Transfer is being effected pursuant to an effective registration statement under the Securities Act and in compliance with the prospectus delivery requirements of the Securities Act.

4. ¨ CHECK IF TRANSFEREE WILL TAKE DELIVERY OF A BENEFICIAL INTEREST IN AN UNRESTRICTED GLOBAL NOTE OR OF AN UNRESTRICTED DEFINITIVE NOTE.

(a) ¨ CHECK IF TRANSFER IS PURSUANT TO RULE 144. (i) The Transfer is being effected pursuant to and in accordance with Rule 144 under the Securities Act and in compliance with the transfer restrictions contained in the Indenture and any applicable blue sky securities laws of any state of the United States and (ii) the restrictions on transfer con-

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tained in the Indenture and the Private Placement Legend are not required in order to maintain compliance with the Securities Act. Upon consummation of the proposed Transfer in accordance with the terms of the Indenture, the transferred beneficial interest or Definitive Note will no longer be subject to the restrictions on transfer enumerated in the Private Placement Legend printed on the Restricted Global Notes, on Restricted Definitive Notes and in the Indenture.

(b) ¨ CHECK IF TRANSFER IS PURSUANT TO REGULATION S. (i) The Transfer is being effected pursuant to and in accordance with Rule 903 or Rule 904 under the Securities Act and in compliance with the transfer restrictions contained in the Indenture and any applicable blue sky securities laws of any state of the United States and (ii) the restrictions on transfer contained in the Indenture and the Private Placement Legend are not required in order to maintain compliance with the Securities Act. Upon consummation of the proposed Transfer in accordance with the terms of the Indenture, the transferred beneficial interest or Definitive Note will no longer be subject to the restrictions on transfer enumerated in the Private Placement Legend printed on the Restricted Global Notes, on Restricted Definitive Notes and in the Indenture.

(c) ¨ CHECK IF TRANSFER IS PURSUANT TO OTHER EXEMPTION. (i) The Transfer is being effected pursuant to and in compliance with an exemption from the registration requirements of the Securities Act other than Rule 144, Rule 903 or Rule 904 and in compliance with the transfer restrictions contained in the Indenture and any applicable blue sky securities laws of any State of the United States and (ii) the restrictions on transfer contained in the Indenture and the Private Placement Legend are not required in order to maintain compliance with the Securities Act. Upon consummation of the proposed Transfer in accordance with the terms of the Indenture, the transferred beneficial interest or Definitive Note will not be subject to the restrictions on transfer enumerated in the Private Placement Legend printed on the Restricted Global Notes or Restricted Definitive Notes and in the Indenture.

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This certificate and the statements contained herein are made for your benefit and the benefit of the Issuer.


[Insert Name of Transferor]

By:
		Name:
		Title:

Dated:

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ANNEX A TO CERTIFICATE OF TRANSFER

1.	The Transferor owns and proposes to transfer the following:

[CHECK ONE OF (a) OR (b)]

(a)	[ ] a beneficial interest in the:

(i)

[ ] 144A Global Note (CUSIP [ ]), or

(ii)

[ ] Regulation S Global Note (CUSIP [ ]), or

(b)	[ ] a Restricted Definitive Note.

2.	After the Transfer the Transferee will hold:

[CHECK ONE]

(a)	[ ] a beneficial interest in the:

(i)

[ ] 144A Global Note (CUSIP [ ]), or

(ii)

[ ] Regulation S Global Note (CUSIP [ ]), or

(iv)

[ ] Unrestricted Global Note (CUSIP [ ])

(b)	[ ] a Restricted Definitive Note; or

(c)	[ ] an Unrestricted Definitive Note

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EXHIBIT C

Form of Certificate of Exchange

[ ], [ ]

The Bank of New York Melon Trust Company, N.A.

▇▇▇ ▇▇▇▇▇▇ ▇▇▇▇▇▇

▇▇▇▇ ▇▇▇▇▇

▇▇▇▇▇▇▇, ▇▇▇▇▇ ▇▇▇▇▇

Attn: Corporate Trust Administration,

re: ATP Oil & Gas Corp.

Re:

ATP Oil & Gas Corporation (the “Issuer”) 111.875% Senior Second Lien Notes due 2015 (the “Notes”)

Ladies and Gentlemen:

(the “Owner”) owns and proposes to exchange the Note[s] or interest in such Note[s] specified herein, in the principal amount of $ in such Note[s] or interests (the “Exchange”). In connection with the Exchange, the Owner hereby certifies that:

(1) EXCHANGE OF RESTRICTED DEFINITIVE NOTES OR BENEFICIAL INTERESTS IN A RESTRICTED GLOBAL NOTE FOR UNRESTRICTED DEFINITIVE NOTES OR BENEFICIAL INTERESTS IN AN UNRESTRICTED GLOBAL NOTE

(a) [ ] CHECK IF EXCHANGE IS FROM BENEFICIAL INTEREST IN A RESTRICTED GLOBAL NOTE TO BENEFICIAL INTEREST IN AN UNRESTRICTED GLOBAL NOTE. In connection with the Exchange of the Owner’s beneficial interest in a Restricted Global Note for a beneficial interest in an Unrestricted Global Note in an equal principal amount, the Owner hereby certifies (i) the beneficial interest is being acquired for the Owner’s own account without transfer, (ii) such Exchange has been effected in compliance with the transfer restrictions applicable to the Global Notes and pursuant to and in accordance with the United States Securities Act of 1933, as amended (the “Securities Act”), (iii) the restrictions on transfer contained in the Indenture and the Private Placement Legend are not required in order to maintain compliance with the Securities Act and (iv) the beneficial interest in an Unrestricted Global Note is being acquired in compliance with any applicable blue sky securities laws of any state of the United States.

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(b) [ ] CHECK IF EXCHANGE IS FROM BENEFICIAL INTEREST IN A RESTRICTED GLOBAL NOTE TO UNRESTRICTED DEFINITIVE NOTE. In connection with the Exchange of the Owner’s beneficial interest in a Restricted Global Note for an Unrestricted Definitive Note, the Owner hereby certifies (i) the Definitive Note is being acquired for the Owner’s own account without transfer, (ii) such Exchange has been effected in compliance with the transfer restrictions applicable to the Restricted Global Notes and pursuant to and in accordance with the Securities Act, (iii) the restrictions on transfer contained in the Indenture and the Private Placement Legend are not required in order to maintain compliance with the Securities Act and (iv) the Definitive Note is being acquired in compliance with any applicable blue sky securities laws of any state of the United States.

(c) [ ] CHECK IF EXCHANGE IS FROM RESTRICTED DEFINITIVE NOTE TO BENEFICIAL INTEREST IN AN UNRESTRICTED GLOBAL NOTE. In connection with the Owner’s Exchange of a Restricted Definitive Note for a beneficial interest in an Unrestricted Global Note, the Owner hereby certifies (i) the beneficial interest is being acquired for the Owner’s own account without transfer, (ii) such Exchange has been effected in compliance with the transfer restrictions applicable to Restricted Definitive Notes and pursuant to and in accordance with the Securities Act, (iii) the restrictions on transfer contained in the Indenture and the Private Placement Legend are not required in order to maintain compliance with the Securities Act and (iv) the beneficial interest is being acquired in compliance with any applicable blue sky securities laws of any state of the United States.

(d) [ ] CHECK IF EXCHANGE IS FROM RESTRICTED DEFINITIVE NOTE TO UNRESTRICTED DEFINITIVE NOTE. In connection with the Owner’s Exchange of a Restricted Definitive Note for an Unrestricted Definitive Note, the Owner hereby certifies (i) the Unrestricted Definitive Note is being acquired for the Owner’s own account without transfer, (ii) such Exchange has been effected in compliance with the transfer restrictions applicable to Restricted Definitive Notes and pursuant to and in accordance with the Securities Act, (iii) the restrictions on transfer contained in the Indenture and the Private Placement Legend are not required in order to maintain compliance with the Securities Act and (iv) the Unrestricted Definitive Note is being acquired in compliance with any applicable blue sky securities laws of any state of the United States.

(2) EXCHANGE OF RESTRICTED DEFINITIVE NOTES OR BENEFICIAL INTERESTS IN RESTRICTED GLOBAL NOTES FOR RESTRICTED DEFINITIVE NOTES OR BENEFICIAL INTERESTS IN RESTRICTED GLOBAL NOTES

(a) [ ] CHECK IF EXCHANGE IS FROM BENEFICIAL INTEREST IN A RESTRICTED GLOBAL NOTE TO RESTRICTED DEFINITIVE NOTE. In connection with the Exchange of the Owner’s beneficial interest in a Restricted

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Global Note for a Restricted Definitive Note with an equal principal amount, the Owner hereby certifies that the Restricted Definitive Note is being acquired for the Owner’s own account without transfer. Upon consummation of the proposed Exchange in accordance with the terms of the Indenture, the Restricted Definitive Note issued will continue to be subject to the restrictions on transfer enumerated in the Private Placement Legend printed on the Restricted Definitive Note and in the Indenture and the Securities Act.

(b) [ ] CHECK IF EXCHANGE IS FROM RESTRICTED DEFINITIVE NOTE TO BENEFICIAL INTEREST IN A RESTRICTED GLOBAL NOTE. In connection with the Exchange of the Owner’s Restricted Definitive Note for a beneficial interest in the [CHECK ONE] [ ] 144A Global Note [ ] Regulation S Global Note, with an equal principal amount, the Owner hereby certifies (i) the beneficial interest is being acquired for the Owner’s own account without transfer and (ii) such Exchange has been effected in compliance with the transfer restrictions applicable to the Restricted Global Notes and pursuant to and in accordance with the Securities Act, and in compliance with any applicable blue sky securities laws of any state of the United States. Upon consummation of the proposed Exchange in accordance with the terms of the Indenture, the beneficial interest issued will be subject to the restrictions on transfer enumerated in the Private Placement Legend printed on the relevant Restricted Global Note and in the Indenture and the Securities Act.

This certificate and the statements contained herein are made for your benefit and the benefit of the Issuer and are dated .


[Insert Name of Transferor]

By:
		Name:
		Title:

Dated:

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EXHIBIT D

FORM OF SUBSIDIARY GUARANTEE NOTATION

For value received, each Subsidiary Guarantor (which term includes any successor Person under the Indenture) has, jointly and severally, unconditionally guaranteed, to the extent set forth in the Indenture and subject to the provisions in the Indenture, dated as of April 23, 2010 (the “Indenture”), among ATP Oil & Gas Corporation, as the Issuer, and The Bank of New York Melon Trust Company, N.A. as trustee (in such capacity, the “Trustee”) and collateral agent (in such capacity, the “Collateral Agent”), the cash payments in United States dollars of principal of, premium, if any, and interest on this Note in the amounts and at the times when due and interest on the overdue principal, premium, if any, and interest, if any, of this Note, if lawful, and the payment or performance of all other obligations of the Issuer under the Indenture or the Notes, to the Holder of this Note, the Trustee and the Collateral Agent, all in accordance with and subject to the terms and limitations of this Note, Article XII of the Indenture and this Subsidiary Guarantee Notation. The obligations of the Subsidiary Guarantors to the Holders of Notes and to the Trustee pursuant to the Subsidiary Guarantee and the Indenture are expressly set forth in Article XII of the Indenture and reference is hereby made to the Indenture for the precise terms of the Subsidiary Guarantee. Each Holder of a Note, by accepting the same, agrees to and shall be bound by such provisions.

THIS SUBSIDIARY GUARANTEE NOTATION SHALL BE GOVERNED BY, AND CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK. Each Subsidiary Guarantor hereby agrees to submit to the jurisdiction of the courts of the State of New York in any action or proceeding arising out of or relating to this Subsidiary Guarantee.

The Subsidiary Guarantee is subject to release upon the terms set forth in the Indenture.

Capitalized terms used but not defined herein have the meanings given to them in the Indenture.

D-1

IN WITNESS WHEREOF, each Subsidiary Guarantor has caused its Subsidiary Guarantee Notation to be duly executed.

Date: [ ], 201[ ]


[ ]

By:
		Name:
		Title:

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ATP OIL & GAS CORPORATION as the Issuer, and THE BANK OF NEW YORK MELON TRUST COMPANY, N.A., as Trustee and Collateral Agent INDENTURE Dated as of April 23, 2010 11.875% Senior Second Lien Notes due 2015

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