STOCK PURCHASE AND SALE AGREEMENT REPSOL YPF, S.A. REPSOL EXPLORACIÓN, S.A. CAVEANT, S.A. REPSOL YPF CAPITAL S.L. PETERSEN ENERGÍA, S.A. February 21, 2008
Exhibit
      7.01
    REPSOL
      YPF, S.A.
    REPSOL
      EXPLORACIÓN, S.A.
    CAVEANT,
      S.A.
    REPSOL
      YPF CAPITAL ▇.▇.
    ▇▇▇▇▇▇▇▇
      ENERGÍA, S.A.
    February
      21, 2008
    "This
        is a
        convenience translation into English of a Spanish-language original
        document.  This translation is without legal effect and, in the event
        of any discrepancy with the Spanish-language original document, the
        Spanish-language original shall prevail."
    1
        TABLE
      OF CONTENTS
    | 1. | DEFINITIONS | 8 | ||
| 2. | RULES
                  OF INTERPRETATION | 8 | ||
| 3. | PURCHASE
                  AND SALE | 9 | ||
| 3.1 | OBJECTIVE | 9 | ||
| 3.2 | PURCHASE
                  AND SALE | 9 | ||
| 4. | PRICE | 9 | ||
| 5. | CONDITION
                  SUBSEQUENT  | 9 | ||
| 5.1 | CONDITION
                  SUBSEQUENT | 9 | ||
| 5.2 | NOTIFICATION
                  OF THE PURCHASE AND SALE | 9 | ||
| 5.3 | TERMINATION
                  OF THE CONTRACT AND RESOLUTION OF THE PURCHASE AND SALE | 10 | ||
| 6. | ACTIONS
                  SIMULTANEOUS WITH THE PURCHASE AND SALE  | 11 | ||
| 6.1 | PAYMENT
                  OF THE PRICE | 11 | ||
| 6.2 | DELIVERY
                  AND RECORDATION OF THE SHARES IN THE NAME OF THE PURCHASER AND
                  NOTIFICATION TO THE COMPANY | 12 | ||
| 6.3 | SIGNING
                  OF THE VENDOR’S LOAN | 12 | ||
| 6.4  | SIGNING AND NOTIFICATION OF THE SHAREHOLDERS' AGREEMENT | |||
| 6.5 | WAIVER.
                  DELIVERY OF CERTIFICATES | 12 | ||
| 7. | COMMITMENTS
                  OF THE PARTIES AFTER THE DATE OF THIS AGREEMENT | 12 | ||
| 7.1 | REGISTRATION WITH
                  THE SEC | 12 | ||
| 7.2 | DISTRIBUTION
                  OF 2006 DIVIDEND BY THE COMPANY | 12 | ||
| 7.3 | MEETING
                  OF THE BOARD OF DIRECTORS OF FEBRUARY 6, 2008.  HOLDING OF THE
                  MEETING | 13 | ||
| 7.4 | PERFORMANCE
                  OF THE BOARD OF DIRECTORS UP TO THE INCORPORATION OF THE DIRECTORS
                  DESIGNATED AT THE PROPOSAL OF PESA | 13 | ||
| 8. | REPRESENTATIONS
                  AND COMMITMENTS OF THE PARTIES | 13 | ||
| 8.1 | REPRESENTATIONS
                  AND COMMITMENTS OF THE VENDOR | 13 | ||
| 8.1.1. | Capacity
                  of the Vendor to Enter Into this Agreement | 13 | ||
| 8.1.2. | Ownership
                  of the Stock | 13 | ||
| 8.1.3. | Corporate
                  Status of the Company | 14 | ||
| 8.1.4. | Nonexistence
                  of Conflict | 14 | ||
| 8.1.5. | Form
                  20-F | 14 | ||
| 8.1.6. | Private
                  Placement | 15 | ||
| 8.1.7. | Prohibition
                  Against Attempts at Directed Sales or Obtaining
                  Purchasers | 15 | ||
| 8.1.8. | Prohibition
                  Against Integration of the Offer | 15 | ||
| 8.2 | REPRESENTATIONS
                  AND COMMITMENTS OF THE PURCHASER | 15 | ||
| 8.2.1. | Capacity
                  to Enter Into this Agreement | 16 | ||
| 8.2.2. | Independence
                  of the Purchaser | 16 | ||
| 8.2.3. | Nonexistence
                  of Conflict | 16 | ||
| 8.2.4. | Intent
                  to Invest | 16 | ||
| 8.3 | INDEMNIFICATION | 17 | ||
| 8.3.1. | General
                  rule except in the case of Clause 8.1.5 (20-F) | 17 | ||
| 8.3.2. | In
                  the case of Clause 8.1.5 (20-F) | 17 | ||
| 8.3.3. | Rules
                  common to the preceding sections | 18 | ||
2
          | 9. | TRANSFER | 19 | ||
| 10. | EXPENSES
                  AND TAXES | 19 | ||
| 11. | NOTIFICATIONS | 19 | ||
| 12. | MISCELLANEOUS | 20 | ||
| 12.1 | CONFIDENTIALITY | 20 | ||
| 12.2 | ANNOUNCEMENTS | 21 | ||
| 12.3 | INTERMEDIATION
                  EXPENSES OR FEES | 21 | ||
| 12.4 | TITLES,
                  HEADINGS, AND APPENDICES | 21 | ||
| 12.5 | SCOPE
                  OF THE AGREEMENT AND PARTIAL NULLITY | 21 | ||
| 12.6 | MODIFICATION
                  AND FORBEARANCE | 21 | ||
| 13. | APPLICABLE
                  LAW AND JURISDICTION | 22 | ||
| 13.1 | APPLICABLE
                  LAW | 22 | ||
| 13.2 | JURISDICTION | 22 | ||
| LIST
                  OF APPENDICES | 1 | |||
3
          In
      Madrid,
      on February 21, 2008.
    PARTIES:
    | (1) | Of
                the first part Repsol YPF, S.A., the parent company of Grupo Repsol
                YPF
                (hereinafter, “Repsol YPF”), established pursuant to
                Spanish law on November 12, 1986 in virtue of public articles of
                incorporation granted before the notary public of Madrid, ▇▇. ▇▇▇▇▇▇
                ▇▇▇▇▇▇▇▇ Fraguero on the same date under number 4,293 of those of
                his /
                her Protocol, a company duly recorded in the Commercial Registry
                of Madrid
                at Volume 7063, 6058 of Section 3rd
                of the
                Companies Book, Sheet 119, Page M-72.059-1.  Repsol YPF has its
                principal executive offices at ▇▇▇▇▇ ▇▇ ▇▇ ▇▇▇▇▇▇▇▇▇▇ ▇▇▇, ▇▇▇▇▇
                ▇▇▇▇▇▇
                and its tax identification code (CIF), ▇-▇▇▇▇▇▇▇▇, is
                current. | 
| Herein
                represented by ▇▇. ▇▇▇▇▇▇▇ ▇▇▇▇▇▇ Niubó, of age of majority, married, a
                Spanish national, with professional domicile at Madrid, ▇▇▇▇▇ ▇▇
                ▇▇
                ▇▇▇▇▇▇▇▇▇▇ ▇▇▇,, and holder of Spanish National Identification Document
                number 40.824.513-L, current, in virtue of a power of attorney granted
                on
                October 29, 2004, before the Notary of Madrid ▇▇▇▇▇▇ ▇▇▇▇▇ ▇▇▇▇▇▇,
                under
                number 2,889 of his protocol. | |
| Hereinafter
                Repsol YPF shall be referred to as the
                “Vendor.” | |
| (2) | Repsol
                Exploración, S.A., (hereinafter, “Repsol Exploración”)
                established pursuant to Spanish law on May 5, 1965 in virtue of public
                articles of incorporation granted before the notary public of ▇▇▇▇▇▇
                ▇▇▇▇▇▇▇ ▇▇▇▇▇▇▇ ▇▇▇▇▇ Real on the same date under number 2,098 of those of
                his / her Protocol, a company duly recorded in the Commercial Registry
                of
                Madrid at Volume 3146, Sheet 1, Page M-53739.  Repsol
                Exploración has its principal executive offices at ▇▇▇▇▇ ▇▇ ▇▇ ▇▇▇▇▇▇▇▇▇▇
                ▇▇▇, ▇▇▇▇▇ ▇▇▇▇▇▇ and its tax identification code (CIF), ▇-▇▇▇▇▇▇▇▇,
                is
                current. | 
| Herein
                represented by ▇▇. ▇▇▇▇▇▇▇ ▇▇▇▇▇▇▇▇▇-▇▇▇▇▇▇ ▇▇▇▇ ▇▇ ▇▇▇▇, of age of
                majority, married, a Spanish national, with professional domicile
                at
                Madrid, ▇▇▇▇▇ ▇▇ ▇▇ ▇▇▇▇▇▇▇▇▇▇ ▇▇▇, and holder of Spanish National
                Identification Document number 786.139-E, current, in virtue of a
                power of
                attorney granted on January 26, 2005, before the Notary of Madrid
                ▇▇▇▇▇▇ ▇▇▇▇▇ ▇▇▇▇▇▇, under number 150 of his protocol. | |
| (3) | Caveant,
                S.A., (hereinafter “Caveant”) established pursuant to A
                law, with Bylaws recorded with the Inspectorate General of Justice
                on July
                2, 1980 under number 2,415 of Book 95, Volume A of Business
                Companies.  Caveant has its principal executive offices at
                Buenos Aires, Avda. Presidente ▇▇▇▇▇ ▇. ▇▇▇▇ 777, and its tax
                identification code (CIF), 30-62881362-7, is current. | 
| Herein
                represented by ▇▇. ▇▇▇▇▇▇▇▇ ▇▇▇▇▇▇▇ Mazarredo, of age of majority,
                married, a Spanish national, with professional domicile at Madrid,
                ▇▇▇▇▇
                ▇▇ ▇▇ ▇▇▇▇▇▇▇▇▇▇ ▇▇▇, and holder of Spanish National Identification
                Document number 485.502-R, current, in virtue of a power of attorney
                granted on February 14, 2008, before the Notary of Buenos Aires ▇▇▇▇▇▇
                ▇▇▇▇▇▇ del Río, under folio 110 of his
                protocol. | 
4
        | (4) | Repsol
                YPF Capital, S.L., a company wholly owned by grupo Repsol (hereinafter,
                “Repsol YPF Capital”) Spanish on December 20, 2002 in
                virtue of public articles of incorporation granted before the notary
                public of Madrid ▇▇▇▇▇▇ ▇▇▇▇▇ ▇▇▇▇▇▇ on the same date under number
                4,166
                of those of his / her Protocol, a company duly recorded in the Commercial
                Registry of Madrid at Volume 18308, Sheet 171, Page
                M-317473.  Repsol YPF Capital has its principal executive
                offices at ▇▇▇▇▇ ▇▇ ▇▇ ▇▇▇▇▇▇▇▇▇▇ ▇▇▇, ▇▇▇▇▇ ▇▇▇▇▇▇ and its tax
                identification code (CIF), ▇-▇▇▇▇▇▇▇▇, is current. | 
| Herein
                represented by ▇▇. ▇▇▇▇▇▇▇▇ ▇▇▇▇▇▇▇ Mazarredo, of age of majority,
                married, a Spanish national, with professional domicile at Madrid,
                ▇▇▇▇▇
                ▇▇ ▇▇ ▇▇▇▇▇▇▇▇▇▇ ▇▇▇, and holder of Spanish National Identification
                Document number 485,502-R, current, in virtue of a power of attorney
                granted on February 19, 2008, before the Notary of Madrid ▇▇▇▇▇▇ ▇▇▇▇▇▇▇
                ▇▇▇▇▇▇▇▇, under number 590 of his protocol. | |
| (5) | Of
                the second part, ▇▇▇▇▇▇▇▇ Energía, S.A. (hereinafter,
                “PESA”), a company established pursuant to Spanish law,
                for the purposes of this transaction, on July 23, 2007 in virtue
                of public
                articles of incorporation granted before the notary public of Madrid,
                Mr.
                ▇▇▇▇ ▇▇▇▇ ▇▇▇▇▇▇▇▇-▇▇▇ ▇▇▇▇ on the same date under number
                2918  of those of his / her Protocol, a company duly recorded in
                the Commercial Registry of Madrid at Volume 24588, Sheet 88, Page
                M-442504.  ▇▇▇▇▇▇▇▇ Energía, S.A. has its principal executive
                offices at Plaza ▇▇▇▇▇ ▇▇▇▇ ▇▇▇▇▇▇▇ ▇, ▇▇▇▇▇ ▇▇▇▇▇▇▇, ▇▇▇▇
                ▇▇▇▇▇, ▇▇▇▇▇,
                ▇▇▇▇▇▇ and its tax identification code (CIF), ▇-▇▇▇▇▇▇▇▇, is
                current. | 
| Herein
                represented by ▇▇. ▇▇▇▇▇▇ ▇▇▇▇▇▇▇▇ Storey, of age of majority, married, an
                Argentine national, with domicile at ▇▇▇▇▇▇▇ ▇▇▇, ▇▇▇
                ▇▇▇▇▇, ▇▇▇▇▇▇
                ▇▇▇▇▇, ▇▇▇▇▇▇▇▇▇, and holder of Alien National Identification Document
                number no. X-9298890-J, current, in virtue of a designation as Managing
                Director pursuant to certified document no. 16 of the protocol of
                ▇▇.
                ▇▇▇▇▇▇ ▇▇▇▇▇▇▇▇-▇▇▇▇▇▇▇ ▇▇▇▇▇▇-Valdecasas dated January 9,
                2008. | |
| Hereinafter
                PESA. shall be referred to as the
                “Purchaser.” | 
Repsol
      Exploración, Caveant, and Repsol YPF Capital appear in this agreement for the
      mere effects of Clause 6.4, Clause 6.5.1 and Clause 7,
      being also applicable what is foreseen in Clause 11, Clause 12 and
Clause 13.
    Hereinafter,
      the Vendor, Repsol Exploración, Caveant, and Repsol YPF Capital shall jointly be
      called “Grupo Repsol YPF.”
    Hereinafter
      the Vendor and Purchaser shall jointly be called the “Parties,”
and any of them individually as a “Party.”
    5
        PREAMBLE:
    | I. | The
                Vendor performs its main activity in the hydrocarbons sector and,
                specifically, in the activities of exploration, exploitation, and
                production of crude and natural gas, the transportation of petroleum
                products, liquid petroleum gases (LPG’s), and natural gas, refining,
                production of a broad range of petroleum products and the sale of
                petroleum products, derived from petroleum, petrochemical products,
                LPG
                and natural gas. | 
| Repsol
                Exploración, Caveant, and Repsol YPF Capital are companies in which Repsol
                YPF has an interest, whose principal activity focuses on the hydrocarbons
                sector and, specifically, in the case of Repsol Exploración, on the
                activities of exploration, exploitation, and production of crude
                and
                natural gas, the transportation of petroleum products, liquid petroleum
                gases (LPG’s) and natural gas, refining, production of a broad range of
                petroleum products and the sale of petroleum products, derived from
                petroleum, petrochemical products, LPG and natural gas.  In the
                case of Caveant and Repsol YPF Capital, their principal activities
                are
                focused on holding shares of and interests in other
                companies. | |
| II. | The
                Purchaser is a Spanish company whose principal activity is the investment,
                management, and administration of securities, bonds and/or
                stock.  The Purchaser is wholly owned by ▇▇▇▇▇▇▇▇ Energía PTY
                Ltd., a company established pursuant to the laws of Australia, duly
                registered in the Securities and Investments Commission (Comisión
                de Valores e
                Inversiones) under company number 128.147.419 and with tax
                identification number N-8001058 J, which, in turn, is wholly owned
                by ▇▇.
                ▇▇▇▇▇▇▇▇▇ ▇▇▇▇▇▇▇▇, ▇▇. ▇▇▇▇▇▇ ▇▇▇▇▇▇▇▇, ▇▇. ▇▇▇▇▇▇▇ ▇▇▇▇▇▇▇▇ y ▇▇.
                ▇▇▇▇▇▇▇▇ ▇▇▇▇▇▇▇▇. | 
| III. | YPF
                S.A. is a corporation established by Decree No. 2778 dated December
                31,
                1990, its corporate bylaws were publicly registered before the appointed
                notary of the National Notary Registry on January 18, 1991 under
                No.
                12. | 
| Registered
                at the Superintendency of Corporations on February 5, 1991 under
                Corporations Book 108, Number 404, Volume A. Tax identification code
                (CUIT), 30-54668997-9 (hereinafter, the
                “Company”). | |
| IV. | The
                Company is a leading international company in the hydrocarbons sector
                in
                Argentina and it forms part of Grupo Repsol YPF. | 
| V. | The
                capital stock of the Company is fully subscribed to and paid in,
                divided
                into 393,312,793 uncertificated shares with a par value of $ 10
                each.  The capital stock is divided into four classes of
                shares. | 
| VI. | Class
                D shares, representing 99.62% of the capital stock of the Company,
                are
                listed on the Buenos Aires Stock Exchange (BCBA) and the New York
                Stock
                Exchange (NYSE) as American Depositary Shares (ADS’s”)
                representing on Class D share each and represented by American Depositary
                Receipts (“ADR’s”) issued by The Bank of New York (hereinafter, the
                “Depositary”) pursuant to the terms of the Deposit Agreement by and
                between the Depository and the Company dated July 1, 1993 (the “Deposit
                Agreement”). | 
6
        | VII. | Grupo
                Repsol YPF is the owner of 389,536,990 Class D
                shares representing [99.04]% of the capital stock of the Company,
                identified in Appendix E-VII. | 
| VIII. | The
                Parties signed a confidentiality agreement on February 19, 2007,
                supplemented on June 26, 2007 through an addendum (hereinafter, the
                “Confidentiality Agreement”). | 
| IX. | Vendor
                has supplied PESA with information on the Company, through reports
                and
                presentations made by Vendor’s staff and outside advisors thereof, for
                PESA and its team of advisors (under confidentiality commitments)
                to
                undertake limited due diligence on the Company in which the advisors
                of
                the Administrative Agent (as designated in the Term
                Loan) participated, from whose limited information no facts or
                circumstances whatsoever arose that contradicted the contents of
                the
                Company’s 20-F, the Parties likewise agreeing that such limited due
                diligence in no way modifies the representations and commitments
                of the
                Vendor and other responsibilities assumed by the Vendor in this
                Agreement. | 
| X. | Given
                the nature and limitations on the information that Vendor agreed
                to
                provide and the fact that the indirect access to it by the Purchaser
                did
                not allow Purchaser or its advisors to confirm the correctness thereof
                against original documentation, the Parties trust to enter the next
                operation in the correctness of the representations and commitments
                made
                by the Vendor in this Agreement. | 
| XI. | Grupo
                Repsol YPF and the Purchaser enter into this Agreement under the
                scope of
                an exception to the obligation to register the Shares (as defined
                below)
                stipulated in Regulation S under the United States Securities Act
                of 1933
                (hereinafter, the “1933 Act”). | 
| XII. | Prior
                to signing this Agreement, the Purchaser signed a finance agreement
                (hereinafter, the “Term Loan”) with certain credit
                institutions (hereinafter, the “Credit Institutions”), a
                copy of which is attached as Appendix E-IX. | 
| XIII. | Simultaneously
                with the signing of this Agreement, Grupo Repsol YPF and the Purchaser
                sign a finance agreement (hereinafter, the “Vendor’s
                Loan”), a copy of which is attached as Appendix
                E-X. | 
| XIV. | Simultaneously
                with the signing of this Agreement, Grupo Repsol YPF and the Purchaser
                sign a shareholders’ agreement (hereinafter, the “Shareholders’
                Agreement”), a copy of which is attached as Appendix
                E-XI. | 
| XV. | Now,
                therefore, the Vendor states its intention to sell to the Purchaser,
                and
                the Puchaser states its intention to purchase from the Vendor, 58,603,606
                Class D shares of the Company, as ADS’s whose circulation has been limited
                with the agreement of the Depository with the inclusion of the legend
                that
                is specified in Appendix 6.2 to that end, represented by ADR’s and
                representing 14.90% of the capital stock of the Company (hereinafter,
                the
                “Shares”), to which end the Parties agree to enter into
                this purchase and sale agreement (hereinafter the
                “Agreement”), which shall be governed by the
                following | 
7
        STIPULATIONS:
    1.           DEFINITIONS
    For
      the
      effect of this Agreement, the terms that appear in Appendix 1, shall be
      construed pursuant to their correlative definitions.
    2.           RULES
      OF INTERPRETATION
    This
      Agreement shall be interpreted pursuant to the special precepts established
      below and the general rules of contract interpretation pursuant to the
      Applicable Law.
    | (i) | All
                the appendices form an integral part of the Agreement, and they have
                the
                same validity and effectiveness as if they were incorporated into
                its main
                body. | |
| (ii) | References
                made to clauses are deemed made to clauses of this
                Agreement. | |
| (iii) | The
                terms “including,” “included,” “inclusive,” and other similar acceptations
                should be interpreted as if they were followed by the phrase, “without
                limitation and merely by way of example.” | |
| (iv) | The
                terms of “to the best of [our / its / his / her / their] knowledge” or “to
                the best of [our / its / his / her / their] knowledge and belief” mean
                with respect to the Vendor the specific degree of knowledge and/or
                the
                degree of knowledge legally required of a member of the board of
                directors, an officer or direct of the Company designated by or at
                the
                request of Grupo Repsol YPF. | |
| (v) | Provisions
                introduced with the phrase “for greater clarity” have in and of themselves
                full normative and binding effects, and they constitute clarifications
                or
                [particularities] that do not prejudice the generality of the preceding
                precepts with respect to such as are indicated. | |
| (vi) | Definitions
                used in singular shall be construed “mutatis mutandis” when used
                in the plural. | |
| (vii) | Except
                if otherwise indicated, any reference to “days” shall be construed as
                “calendar days” or “consecutive days.”  When the phrase
                “business days” appears it shall be construed as referring to the days
                that are also working days, from Monday to Friday, in the cities
                of Buenos
                Aires (Argentina) and Madrid (Spain) and New York (United
                States). | |
| (viii) | Any
                reference in this Agreement to shares or participations in a specific
                legal person shall include both the shares, the parts of interest,
                and any
                other form of participation in the capital of such legal person,
                as well
                as any certifies issued by such legal person or any third party
                representing shares, parts of interest or participation in such legal
                person, including without implying limitation, “ADS’s,” “ADR’s” and any
                other certificate of deposit or custody of shares, parts of interest
                or
                participation in such legal person. | 
8
        | 3. | PURCHASE
                  AND SALE | 
| 3.1 | Objective | 
| The
                  objective of this Agreement is the purchase and sale by the Vendor
                  from
                  the Purchaser of the Shares, with all their inherent rights and
                  obligations.  The Shares are sold to the Purchaser forming a
                  single and indivisible whole given that the purchase and sale are
                  agreed
                  as a joint sale. | |
| 3.2 | Purchase
                  and Sale | 
| The
                  Vendor sells, cedes, and transfers the Shares, free of charges
                  or Liens of
                  any nature, to the Purchaser, who acquires them under those conditions,
                  all pursuant to the terms and conditions of this Agreement (hereinafter,
                  the “Purchase and Sale”). | |
| 4. | PRICE | 
| The
                  Price agreed by the Parties is US$ 38.13758 per Share; that is
                  US$
                  2,235,000,000 in total for all of the Shares (hereinafter, the
                  “Price”). | |
| 5. | CONDITION
                  SUBSEQUENT | 
| 5.1 | Condition
                  Subsequent | 
The
      Purchase and Sale is subject to the following Condition Subsequent: (i) failure
      to obtain within a period of 12 months from the date of this Agreement, the
      authorization for the purchase and sale from CNDC (either expressly or in the
      form of a written recognition, issued by the Department of Foreign Trade of
      Argentina or the entity that replaces it in the future as the supreme Argentine
      antitrust
    authority,
      stating that tacit authorization has been given); or (ii) the denial of such
      authorization; or (iii) the imposition by the CNDC of conditions or obligations
      that could have a material adverse impact on any of the Parties or on the
      Company (hereinafter, the “Condition Subsequent”).
    5.2         Notification
      of the Purchase and Sale
    As
      soon as
      possible, and in any case within a period of seven (7) calendar days from the
      date of this Agreement, the Parties shall notify the CNDC of the Purchase and
      Sale in order to obtain the express or implied authorization or authorizations
      for the Purchase and Sale or the non-opposition to the transaction on the part
      of the antitrust authorities.
    The
      Parties shall agree on any type of communication that must be made to the
      CNDC.
    The
      Parties undertake to do whatever is within their reach to execute the Necessary
      Acts and to put in order all documents that are necessary to obtain the
      authorization or authorizations or the non-opposition to the Purchase and Sale
      on the part of the CNDC within the period of 12 months from the date of this
      Agreement.
    9
        The
      Parties shall keep each other informed of the administrative procedure
      instituted pursuant to Clause 5.1.
    The
      Parties shall agree on any information or data that must be provided to the
      pertinent antimonopoly authorities in relation to this purchase and sale and,
      in
      particular, the application documents.  Likewise, the Parties
      undertake to notify the other Party promptly of any verbal or written
      communication they receive in relation to the administrative procedure in
      question, as well as to deliver a copy of the final decision.
    5.3         Termination
      of the Contract And Resolution of the Purchase and
      Sale
    If
      the
      Condition Subsequent foreseen in Clause 5.1 (i) or Clause 5.1 (ii)
occurs, this Agreement shall be terminated automatically, and
      the Parties
      shall return in full the consideration received.  To that end, at up
      certifiable request of any of the Parties which establishes and proves that
      the
      cause for contractual dissolution has occurred, the Parties shall appear within
      a period of ten (10) days from receipt of this notification (hereinafter, the
      “Date of Notification”) before the Notary of Madrid, ▇▇. ▇▇▇▇▇▇
      ▇▇▇▇▇ ▇▇▇▇▇▇▇ ▇▇▇▇▇▇▇▇, to formalize a statement and Contract dissolution
      document, in which simultaneously:
    (i)
      the
      Purchaser will return the Shares to the Vendor, free of charges and liens;
      and
    (ii)
      the
      Vendor will satisfy the Purchaser in accordance with the following irrevocable
      payment conditions in an amount equal to: (a) the amounts owed by the Purchaser
      under the Term Loan in accordance with the established in Clause
      2.04(b)(v) of Term Loan, plus (b) the amounts that the Adjusted Cash Price
      exceeds the amount foreseen in letter (a) of this paragraph, minus (c) any
      Cash
      Dividend, provided that if the quantity foreseen in letter (a) of this paragraph
      exceeds that resulting from subtracting the Cash Dividends from the Adjusted
      Cash Price, the Purchaser shall simultaneously refund to the Vendor such
      difference in cash or through the total or partial assignment of its rights
      under the Interest Cap Rate.
    The
      Vendor
      will refund such amount as follows: (a) the necessary amount to cancel the
      outstanding balance on the Term Loan transferring the same to the account held
      by the Global Coordinator under the Term Loan, and (b) the remainder, if any,
      to
      be transferred to the account at Credit Suisse Nº
1460-0001-15000036561.
    For
      the
      purpose of the foreseen in this Clause 5.3:
    “Adjusted
      Cash Price” means US$ 1.018.850.000,00 plus an amount representing
      interest owed at a 5% annual rate based on a 365-day year calculated by the
      number of days elapsed from the date this Agreement is signed up to the Date
      of
      Notification.
    “Cash
      Dividends” means any dividends paid in cash by the Company on the
      Shares from the signing of this Agreement to the Date of Notification, excluding
      the 2006 Dividend.
    “Interest
      Cap Rate” means the interest rate limit agreement or agreements that
      PESA signs in virtue of Article 5.09 of the Term Loan and the interest rate
      limit agreement or agreements that PESA signs to reach 100% of the interest
      payment obligations under such Term Loan.
    10
        Insofar
      as
      the expenses inherent to the dissolution of the Purchase and Sale, each Party
      shall assume its own at its expense and the common ones shall be borne in
      halves.
    The
      Parties acknowledge and accept that the occurrence of the Condition Subsequent
      shall not give rise to a claim by any of the Parties against the other Party
      for
      any damages or injuries, except if the breach or occurrence of the Condition
      Subsequent is attributable to a breach by any of the Parties of a specific
      obligation to do or not to do in Clause 5.2.
    In
      no case
      shall the Parties be obligated, in order to obtain the authorizations (and/or
      comply with them), to perform (or assume obligations not to do) or to comply
      with any conditions imposed by the antitrust authorities, except those
      obligations that cannot have a material adverse effect on the financial position
      of the party affected by such obligation.
    If
      the
      Condition Subsequent stipulated in Clause 5.1 (iii) occurs, the affected Party,
      or any of the Parties (in the case of conditions or obligations that affect
      the
      condition of the Company), may terminate this Agreement automatically, and
      the
      Parties shall proceed pursuant to the provisions for the case of termination
      by
      express or implied denial of the authorization in sections 5.3. (i) and
      (ii).  To that end, upon certifiable request by a Party which
      establishes and proves that the cause of contractual termination has occurred,
      the Parties shall appear within a period of ten (10) days from receipt of this
      notification to the aforementioned Notary of Madrid for the aforementioned
      effects.
    6.           ACTIONS
      SIMULTANEOUS WITH THE PURCHASE AND SALE
    The
      Parties agree that each and every one of the actions stipulated in this
Clause 6 shall occur simultaneously and in a single act upon the signing
      this Agreement.  The Purchase and Sale shall not be completed until
      each and every one of the actions stipulated in this Clause 6
      occurs.
    | 6.1 | Payment
                of the Price | 
| The
                Purchaser shall pay the Vendor the Price as follows:  (i) US$
                1,018,850,000 through a funds transfer to bank account [•] with the bank
                voucher that proves the deposit of funds in the Vendor’s account owned by
                Vendor Swift Code [redacted] number [redacted] as serving as
                sufficient receipt ; (ii) US$ 201,150,000 through a certifiable and
                irrevocable assignment in payment to the Vendor by PESA of its right
                to
                collect the dividends for fiscal year 2006 in an amount up to which
                belong
                to it as a shareholder in the Company on the Shares, to be made through
                the grant of the assignment included in this Agreement as Appendix
                6.1,
                with such serving as sufficient receipt and payment letter for such
                amount, and (iii) US$ 1,015,000,000 corresponding to the amount financed
                through the Vendor’s Loan signed by the Parties in this document, with
                such serving as sufficient receipt and payment letter for such
                amount. | 
11
        | 6.2 | Delivery
                    and Recordation of the Shares in the Name of the Purchaser and
                    Notification to the Company | |
| The
                    Vendor shall deliver to the Purchaser “ADR” certificates representing the
                    Shares, which shall bear a legend in the English language indicating
                    that
                    their circulation has been limited pursuant to the Depository
                    agreement as
                    per the Spanish text that is detailed in Appendix 6.2, | ||
|  and
                    it shall undertake all other acts that are necessary to perfect
                    the
                    registration of the Shares in the name of the Purchaser at the
                    time this
                    Agreement is signed. | ||
| 6.3 | Signing
                    of the Vendor’s Loan | |
| The
                    Parties shall sign the Vendor’s Loan which is attached as Appendix
                    E-X. | ||
| 6.4 | Signing
                    and Notification of the Shareholders’
                    Agreement | |
| The
                    Parties shall sign the Shareholders’ Agreement which is attached as
                    Appendix E-XI. | ||
| 6.5 | Waiver.
                    Delivery of Certificates | |
| 6.5.1 | Grupo
                    Repsol YPF hereby irrevocably waives making any claim, directly
                    or
                    indirectly, against the Company for any act, event, or omission
                    caused or
                    occurring prior to the signing hereof. Consequently, Repsol YPF,
                    undertakes to perform the Necessary Acts so its subsidiary companies
                    do
                    not make any claim against the Company for any act, event, or
                    omission
                    caused or occurring prior to the signing hereof. Nevertheless
                    the waiver
                    hereby made by Grupo Repsol YPF will not in any case include
                    any financial
                    claims, commercial claims or claims from services derived from
                    the
                    activities or business performed by any of the companies of the
                    Repsol YPF
                    group to the Company and its subsidiaries during the ordinary
                    course of
                    business. | |
| 6.5.2 | The
                    Purchaser hereby irrevocably waives making any claim against
                    the Company
                    for any act, event, or omission caused or occurring prior to
                    the signing
                    hereof. | |
| 7. | Commitments
                    of the Parties after The Date of this
                    Agreement | |
| 7.1 | Registration
                    with the SEC | |
| Repsol
                    YPF Group undertakes to comply with and cause the Company to
                    timely comply
                    with the terms of the Registration Rights
                    Agreement.  The Parties undertake to perform the Necessary
                    Acts to that end. | ||
| 7.2 | Distribution
                    of 2006 Dividend by the Company | |
| The
                    Parties undertake to perform the Necessary Acts for the Company
                    to
                    distribute the 2006 Dividend in cash, before May 15,
                    2008. | ||
| The
                    Vendor undertakes to, immediately after the payment in cash of
                    the
                    dividend mentioned in the previous paragraph is made, transfer
                    to the
                    Company’s account the amount necessary to cancel the total principal
                    plus
                    interest, earned and unpaid up to the date of that cancellation
                    of the
                    debt it has contracted with Company (hereinafter, the “Intercompany
                    Note”). | ||
12
        | 7.3 | Meeting
                of the Board of Directors of February 6, 2008.  Holding of the
                meeting | |
| At
                the meeting of the Board of Directors held on February 6, 2008, the
                Board
                of Directors of the Company resolved to call for the Ordinary and
                Extraordinary Shareholders’ Meeting of the Company to be held on March 8,
                2008 with the agenda indicated in Appendix 7.3 of this
                Agreement. | ||
| The
                Parties undertake to perform the Necessary Acts so that on such date
                (i)
                the persons proposed by each Party be designated as full Directors,
                alternate Directors, full Trustees and alternate Trustees, respectively,
                of the Company, and (ii) the Company’s Shareholders’ Meeting approve the
                amendment of the Company’s Corporate Bylaws so that the Clauses detailed
                in Appendix 7.3-2nd
                remain
                written according to the text indicated in such Annex. | ||
| 7.4 | Performance
                of the Board of Directors up to the incorporation of the Directors
                designated at the proposal of PESA | |
| Unless
                by joint agreement to the contrary by both Parties, Group Repsol
                YPF
                undertakes to perform the Necessary Acts so that the Company’s Board of
                Directors does not adopt any decision with regard to any Special
                Matters
                (as these are defined in the Shareholders’ Agreement), nor any of such
                Special Matters in the Directory are considered, approved or resolved
                by
                the Board of Directors of the Company or any body of the Company,
                up until
                the Board of Directors of the Company is made up of the Directors
                proposed
                by each Party pursuant to their rights under the Shareholders’
                Agreement. | ||
| 8. | REPRESENTATIONS
                AND COMMITMENTS OF THE PARTIES | |
| 8.1 | Representations
                and Commitments of the Vendor | |
| The
                Vendor represents to the Purchaser that the representations and
                commitments stated in this Clause 8.1 are true and exact on the
                date of this Agreement. | ||
| The
                Vendor shall not be liable in any manner whatsoever, express or implied,
                for any matter related to the Company or the Shares that is not expressly
                and directly included in the representations and commitments included
                in
                this Clause 8.1. | ||
| 8.1.1. | Capacity
                of the Vendor to Enter Into this Agreement | |
| Grupo
                Repsol YPF has the capacity necessary to enter into this Agreement
                and to
                perform each one of the obligations that it assumes in virtue hereof,
                such
                that the obligations derived from this Agreement constitute valid
                and
                binding obligations for Grupo Repsol YPF, enforceable under their
                terms. | ||
| 8.1.2. | Ownership
                of the Stock | |
| The
                Vendor is owner of the Shares, with all the rights that are inherent
                thereto as Class D shares of the Company. The Shares represent fourteen
                point ninety percent (14.90%) of the capital stock of the Company
                (counting any option, uncapitalized contribution, right to receive
                shares
                in the Company or any security or debt convertible into shares as
                if that
                right or conversion had materialized), are duly issued, fully paid
                in and
                are sold and transferred, free of charges and Liens or any other
                right-party rights, except for the restrictions established in Article
                7
                of the Corporate Bylaws and pursuant to the ▇▇▇▇ ▇▇▇. | ||
| The
                Company has not issued or granted options, securities of any nature
                convertible into shares, rights to receive or subscribe to shares,
                nor are
                there uncapitalized contributions of any
                nature. | ||
13
        | 8.1.3. | Corporate
                  Status of the Company | ||
| The
                  Company was duly established, it exists validly and has full legal
                  capacity pursuant to its Corporate Bylaws and the legislation that
                  is
                  applicable to it to perform the activities inherent to its
                  objective. | |||
| 8.1.4. | Nonexistence
                  of Conflict | ||
| The
                  entering into and execution of this Agreement and such other documents
                  as
                  must be granted or executed by Grupo Repsol YPF pursuant to that
                  herein
                  stipulated: | |||
| (a) | do
                  not constitute a breach of Regulations, laws, regulations, legal
                  provisions or court orders applicable to Grupo Repsol YPF or the
                  Company; | ||
| (b) | do
                  not require the consent, approval, or authorization of any public
                  authority, except such as may be necessary pursuant to the provisions
                  of
                  Clause 5.1; | ||
| (c) | do
                  not breach any article of the bylaws or the articles of incorporation
                  of
                  Grupo Repsol YPF or the Corporate Bylaws of the Company;
                  and | ||
| (d) | do
                  not contravene any contract, agreement, or material instrument
                  to which
                  Grupo Repsol YPF or the Company are parties. | ||
| 8.1.5. | Form
                  20-F | ||
| The
                  Vendor represents that the Company’s Form 20-F corresponding to the fiscal
                  year ended December 31, 2006 (hereinafter, the “20-F”)
                  has been submitted to the SEC by the deadline and pursuant to all
                  the
                  formalities required by the applicable law. | |||
| To
                  the best of the Vendor’s knowledge and belief, the information contained
                  in the 20F is correct and the Company has included in the 20-F
                  all the
                  information and it has reflected all the material events which,
                  pursuant
                  to the regulatory precepts thereof, must be reflected in the 20-F,
                  and it
                  has done so completely and without omitting information with respect
                  to
                  those events which pursuant to those precepts should have been
                  included
                  therein, at the date it was submitted to the SEC. | |||
| The
                  Vendor is not aware of any information which should have been included
                  in
                  the 20-F but was not included in the 20-F or was included
                  incompletely.  Likewise, it is not aware of (i) information
                  which, subsequent to the submission of the 20-F, should have been
                  reported
                  to the SEC and was not reported or was incompletely or incorrectly
                  included; or (ii) materially relevant information which, subsequent
                  to the
                  submission of the 20-F, should have been reported to the regulatory
                  authorities of the stock exchanges on which the Company is listed
                  that was
                  not reported or that was reported incompletely or
                  incorrectly. | |||
14
        | 8.1.6. | Private
                  Placement | ||
| Assuming
                  the truth of the representations and commitments of the Purchaser
                  established in Clause 8.2, registration is not required in virtue
                  of the
                  1933 Act for the offering and sale of the Shares by the Vendor
                  to the
                  Purchaser pursuant to the terms of this Agreement.  Except in
                  virtue of the two Registration Rights Agreements signed today
                  (Registration Rights Agreements), neither the Vendor nor the
                  Company have granted or entered into any agreement to grant any
                  right to
                  any person (including the piggyback share registration rights of
                  an offer
                  (“piggyback” registration rights)) in order to obtain
                  registration of any security of the Company with the Securities
                  and
                  Exchange Commission of the United States (U.S. Securities and Exchange
                  Commission) (“SEC”) or any other governmental authority which was not
                  performed or waived. | |||
| 8.1.7. | Prohibition
                  Against Attempts at Directed Sales or Obtaining
                  Purchasers. | ||
| Neither
                  the Vendor nor the Company nor any of their respective affiliates,
                  nor any
                  person acting in their behalf have engaged in any “general attempt to
                  obtain purchasers” (general solicitation) or “general
                  advertising” (general advertising) (as such terms are used in
                  Regulation D under the ▇▇▇▇ ▇▇▇) or any “directed sales attempt”)
                  (directed selling efforts) (as such term is used in Rule 902(c)
                  of Regulation S under the ▇▇▇▇ ▇▇▇) in relation to the offering
                  or sale of
                  any of the Shares.  The Vendor, the Company, and their
                  respective Affiliates and any person acting in their behalf have
                  complied
                  with and shall comply with all the requirements related to offering
                  restrictions established in Regulation S under the 1933
                  Act. | |||
| 8.1.8. | Prohibition
                  Against Integration of the Offer. | ||
| Neither
                  the Vendor, the Company, their subsidiaries or any of their respective
                  Affiliates, nor any other person acting in their behalf, have engaged,
                  directly or indirectly, at any time during the past six months,
                  in any
                  offering or sale of any of the Company’s securities nor has it [sic] tried
                  to obtain any offer to purchase any security under circumstances
                  which (i)
                  would eliminate the availability of the exemption from registration
                  in
                  virtue of Regulation S under the 1933 Act in relation to the offer
                  and
                  sale by the Vendor of the Shares as contemplated in this Agreement
                  or (ii)
                  would cause the integration of the offer of Shares in virtue of
                  this
                  Agreement with prior offers by the Vendor or the Company for the
                  effects
                  of any applicable law, regulation, or shareholder approval provisions,
                  including, without restriction, in virtue of the rules and regulations
                  of
                  any Securities Exchange. | |||
| 8.2 | REPRESENTATIONS
                  AND COMMITMENTS OF THE PURCHASER | ||
| The
                  Purchaser states to the Vendor that the representations and commitments
                  expressed in this Clause 8.2 are true and correct at the date of
                  this Agreement. | |||
15
          | 8.2.1. | Capacity
                  to Enter Into this Agreement | ||
| The
                  Purchaser has the capacity necessary to enter into this Agreement
                  and to
                  perform each one of the obligations that it assumes in virtue hereof,
                  such
                  that the obligations derived from this Agreement constitute valid
                  and
                  binding obligations for the Purchaser, enforceable under their
                  terms. | |||
| 8.2.2. | Independence
                  of the Purchaser | ||
| The
                  Purchaser represents that it acts in its own behalf and for its
                  sole
                  benefit and interest. | |||
| 8.2.3. | Nonexistence
                  of Conflict | ||
| The
                  entering into and execution of this Agreement and such other documents
                  as
                  must be granted or executed by the Purchaser pursuant to that herein
                  stipulated: | |||
| (a) | do
                  not constitute a breach of Regulations, laws, regulations, legal
                  provisions or court orders applicable to the Purchaser; | ||
| (b) | do
                  not require the consent, approval, or authorization of any public
                  authority, except those established in this Agreement, if
                  applicable; | ||
| (c) | do
                  not breach any article of the bylaws or the articles of incorporation
                  of
                  the Purchaser or the Corporate Bylaws of the Company;
                  and | ||
| (d) | do
                  not contravene any contract, agreement, or material instrument
                  to which
                  the Purchaser are parties. | ||
| 8.2.4. | Intent
                  to Invest | ||
| Purchaser
                  understands that the Shares (as ADR’s) are “restricted securities”
                  (restricted securities) and have not been registered pursuant to
                  the 1933
                  Act or any securities law of any state of the United States and
                  it
                  acquires the Shares in its own behalf and without a view toward
                  their
                  public sale or distribution, or resale in relation to such public
                  sale or
                  distribution, without prejudice to the right of the Purchaser,
                  subject to
                  the provisions of this Agreement and the Shareholders’ Agreement, to sell
                  or otherwise dispose of, at any time, all or part of such Shares,
                  as the
                  case may be, pursuant to a valid registration statement in virtue
                  of the
                  1933 Act or in virtue to an exemption to such registration and
                  pursuant to
                  current federal and state securities laws in the United
                  States.  The Purchaser does not currently have any contract,
                  plan, or agreement, directly or indirectly, with any person for
                  the
                  distribution of any of the Shares to any person or entity nor through
                  any
                  person or entity; it being established, however, that through the
                  statements made herein, the Purchaser does not agreed to keep any
                  of the
                  Shares for a minimum period of time. | |||
16
          | 8.3 | Indemnification | ||
| 8.3.1. | General
                  rule except in the case of Clause 8.1.5
                  (20-F) | ||
| Each
                  one of the Parties, under the terms indicated in this Clause, expressly
                  and irrevocably undertakes to indemnify and hold the other Party
                  harmless
                  of any foreseeable damages or losses that it may incur as a result
                  of any
                  default hereunder and/or any imprecision, omission, or lack of
                  truth of
                  the Representations and Commitments established in the aforementioned
                  clauses. | |||
| The
                  maximum total liability of the Parties for default on the provisions
                  of
                  these clauses shall in all cases by the Price of the Purchase and
                  Sale. | |||
| In
                  these cases the Parties shall not exercise any of these actions
                  or claims
                  once the statute of limitations has lapsed. | |||
| 8.3.2. | In
                  the case of Clause 8.1.5 (20-F) | ||
| With
                  respect to Clause 8.1.5, the Purchaser may institute actions or
                  claims
                  against the Vendor for any monetary damage or loss it suffers as
                  a result
                  of any imprecision, omission or lack of truth with respect to facts
                  that
                  were known by the Company or should have been known because documentation
                  existed in it, which because of their material importance should
                  have been
                  reflected in the 20-F, related to the materially relevant information
                  provided or which should have been provided in the Company’s 20-F pursuant
                  to the regulatory precepts thereof, as well as the aforementioned
                  information reported or that should have been reported to the SEC
                  after
                  the 20-F. | |||
| The
                  Parties shall appoint by common accord, within a period of ten
                  (10)
                  business days from when the Purchaser has notified the Vendor of
                  the
                  existence of actions or claims under this clause, an independent
                  expert
                  from among the five (5) largest international audit firms in order
                  for it
                  to determine by a report the possible existence and amount of the
                  imprecision, omission, or lack of truth and, if applicable, the
                  monetary
                  damage caused.  Once that period from the receipt of the notice
                  by the other Party has lapsed without agreement having been reached,
                  the
                  expert shall be appointed by lottery before a notary public among
                  the four
                  firms proposed (two (2) by each one of the Parties) from among
                  the five
                  (5) largest international audit firms.  Such report shall be
                  binding and final for the Parties, who expressly waive appeal of
                  the
                  conflict resolution proceeding established in Clause 13.2 to settle
                  any
                  matter covered by the aforementioned report or any other jurisdiction
                  that
                  might be applicable to them.  The Parties may only appeal the
                  proceeding established in Clause 13.2 for matters related to the
                  execution
                  and/or implementation of the conclusions and decisions of the
                  aforementioned report. | |||
| In
                  the cases cited in this Clause 8.3.2, the Purchaser shall not exercise
                  any
                  action or claim after two (2) years have elapsed from the Date
                  of this
                  Agreement, except for cases of fraud on the part of the Vendor,
                  in which
                  case the period of the statute of limitations shall be followed
                  if it is
                  greater than the two (2) year period. | |||
| Additionally,
                  in no case may the total accrued amount of the indemnification
                  to be paid
                  by the Vendor to the Purchaser for indemnifiable losses which the
                  Purchaser might suffer as a result of any imprecision, omission
                  or lack of
                  truth under Clause 8.1.5 exceed ten (10) percent (10%) of the Price,
                  except for cases of fraud by the Vendor, in which case the total
                  amount of
                  the indemnification shall have as a maximum limit the total Price
                  of the
                  Purchase and Sale. | |||
17
          | 8.3.3. | Rules
                  common to the preceding sections | ||
| If
                  with respect to an event that gives rise to damage, the Purchaser or the
                  Company had a right to recover from a third party (including any
                  indemnification under an insurance policy in effect on the date
                  of this
                  Agreement) any amount, Purchaser and Vendor shall cooperate for
                  the
                  Company to take such acts as are necessary to execute against the
                  third
                  party recovery of such amount.  The amount of the
                  indemnification if applicable effectively recovered from the third
                  party,
                  less the expenses incurred in relation to the claim, shall (i)
                  if it was
                  received by the Purchaser, be returned immediately to the Vendor
                  (or, if
                  the indemnification for the damages has not yet been paid to the
                  Purchaser, the amount received by the Purchaser shall be deducted
                  from the
                  indemnification for which the Vendor is liable) in the same proportion
                  as
                  if such indemnification was paid or should have been paid; or (ii)
                  if it
                  was received by the Company, the proportional amount (with respect
                  to the
                  Purchaser’s interest in the Company’s capital) of the amount received by
                  the Company shall be, if the indemnification was paid by the Purchaser,
                  returned by it to the Vendor or, if it has not yet been paid by
                  the
                  Purchaser, deducted from the indemnification for which the Vendor
                  is
                  liable, in the same proportion as this amount had paid such
                  indemnification [sic]. | |||
| If
                  one Party knows of the existence of an event or circumstance that
                  gives
                  rise to the obligation to indemnify, such Party shall claim the
                  indemnification from the other Party, providing, if it exists,
                  the
                  information that documents the event or circumstance that gives
                  rise to
                  the obligation to identify, as well as a brief summary
                  thereof. | |||
| Once
                  the corresponding claim for indemnification is received, the Party
                  that
                  has received it shall notify the Party that has sent it in writing,
                  within
                  a period of 15 business days, of its full or partial rejection
                  or
                  acceptance of the claim.  The lack of such notification within
                  such period shall be deemed a total rejection of the
                  claim. | |||
| In
                  case of (full or partial) acceptance of the claim, the amounts
                  claimed
                  (and fully or partially accepted) shall be paid, without need of
                  an
                  additional request, within a 30-day period from such
                  acceptance. | |||
| In
                  case of (full or partial) rejection of the claim, as the case may
                  be, the
                  claim in dispute shall be resolved pursuant to the provisions of
Clause
                  13. | |||
18
        9.           TRANSFER
    Neither
      the Vendor nor the Purchaser may assign in whole or in part the rights and
      obligations derived from this Agreement to any third party unless it is
      expressly agreed in advance and in writing by the other Party.  Such
      written consent shall be obtained even if the assignment were made in favor
      of
      companies of the same group or takes place through the complete transfer of
      the
      company (for example, a merger).
    If
      the
      Purchaser were to transfer its rights or obligations derived from this Agreement
      in any manner or under any legal recourse, without obtaining written consent
      from the Vendor, the Vendor may choose, at its sole discretion, to rescind
      this
      Agreement automatically or to file a claim against the Purchaser for such
      damages and injuries as derive from the nonperformance of this
      obligation.
    Notwithstanding
      the foregoing, the Vendor gives its express consent for the Purchaser to
      transfer, totally or partially, the rights of economic content, but not the
      obligations, arising for the Purchaser of this Agreement in favor of the
      financial entities that have partially financed the payment of the
      Price.
    10.         EXPENSES
      AND TAXES
    The
      expenses and taxes derived from the negotiation, formalization, and execution
      of
      this Agreement shall be borne by the Parties indicated below:
    | (i) | The
                expenses for formalization of this Agreement before a Notary Public
                shall
                be borne by the Purchaser and Vendor in equal parts; | |
| (ii) | The
                fees and expenses of legal, accounting, tax advisors, investment
                banks,
                consultants, auditors, specialists in the hydrocarbon industry or
                any
                other professionals shall be borne by the Party which in each case
                hired
                them. | |
| (iii) | The
                taxes resulting from the formalization and execution of this Agreement
                shall be borne by such Party as the Applicable Law in each case
                determines. | 
11.          NOTIFICATIONS
    All
      communications and notifications that the Parties exchange in relation to this
      Agreement to be effective between them shall be made in writing, in the Spanish
      language, by (i) personal delivery with written confirmation of receipt by
      the
      other party; (ii) through a notary made by a Notary Public; (iii) by bureau
      fax;
      or (iv) by any other means that leaves certifiable evidence of its due receipt
      by the address or addressees.  The Parties establish the following
      addresses or fax numbers for the effects of notifications:
    Grupo
      Repsol YPF:
    ▇▇▇▇▇
      ▇▇
      ▇▇ ▇▇▇▇▇▇▇▇▇▇ ▇▇. ▇▇▇-▇▇▇
    ▇▇▇▇▇
      ▇▇▇▇▇▇ (▇▇▇▇▇)
    Fax:  (▇▇)
      ▇▇ ▇▇▇ ▇▇ ▇▇
    Attention:  Corporate
      Director of Strategy and Development
    With
      a
      copy to
    Fax:  (▇▇)
      ▇▇ ▇▇▇ ▇▇ ▇▇
    Attention:  Corporate
      Director for Legal Matters
    19
        Purchaser:
    Cerrito
      ▇▇▇, ▇▇▇
      ▇▇▇▇▇
    ▇
      ▇▇▇▇ ▇▇▇
      ▇▇▇▇ ▇▇ ▇▇▇▇▇▇ ▇▇▇▇▇ (▇▇▇▇▇▇▇▇▇)
    Fax:  (▇▇)
      ▇▇ ▇▇ ▇▇ ▇▇ ▇▇
    Attention:  ▇▇.
      ▇▇▇▇▇▇▇ ▇▇▇▇▇
    With
      a
      copy
    Fax;
      (▇▇)
      ▇▇ ▇▇ ▇▇ ▇▇ ▇▇
    Attention:  ▇▇.
      ▇▇▇▇▇ Dacomo
    Any
      correspondence sent to the preceding addresses or fax numbers shall be deemed
      receive by the addressee except if the addressee had previously informed the
      sender of any change thereto through any of the aforementioned
      means.
    12.         MISCELLANEOUS
    12.1       Confidentiality
    The
      content of this Agreement shall be entirely confidential, the Parties being
      obligated not to disclose the content hereof to any third party,
      except:
    | (a) | Pursuant
                to a court or administrative order or another legal
                obligation; | |
| (b) | In
                order to demand or facilitate compliance with the rights and obligations
                derived from the Agreement; | |
| (c) | If
                applicable, in order to meet the requirements related to notification
                to
                the authorities cited in Clause 5.2; | |
| (d) | Insofar
                as necessary, to meet or comply with the reporting obligations that
                are
                required with respect to regulatory and supervisory bodies in the
                capital
                markets where the Company, the Vendor or, if applicable, the Purchaser
                are
                listed. | |
| (e) | In
                order to provide information to their advisors and auditors, and
                when
                financial institutions reasonably need to know it, provided that
                they are
                obligated by law or contract to maintain the confidentiality of the
                information obtained. | 
Exceptionally,
      the Parties shall be authorized to make the mandatory communications required
      by
      an official body.  The Parties to this Agreement shall agree, insofar
      as possible, on any mandatory communications.
    20
        | 12.2 | Announcements | 
| The
                  Purchaser and Vendor shall agree, acting mutually, on the time
                  and content
                  of any press release or public announcement (including material
                  facts), in
                  strict observance of the duties and obligations required by the
                  applicable
                  regulations. | |
| The
                  Parties may not communicate any information except if their written
                  consents have been mutually stated in advance.  This provision
                  is not applicable to the cases described in the foregoing Clause
                  12.1. | |
| 12.3 | Intermediation
                  Expenses or Fees | 
| Without
                  prejudice to the generalness of the provisions of Clause 10, the
                  Parties state that neither the signing of this Agreement nor the
                  formalization of the purchase and sale shall accrue any type of
                  fee (i.e.
                  finder’s fee or broker’s fee) either for the Company or
                  a Party other than the one that has contracted those
                  services. | |
| 12.4 | Titles,
                  Headings, and Appendices | 
| The
                  titles and headings of the sections and the clauses and subclauses
                  of this
                  Agreement are inserted to facilitate its reading but they do not
                  form part
                  nor should they be taken into account at the time of interpreting
                  it. | |
| The
                  appendices form an integral part of the Agreement for all
                  effects. | |
| 12.5 | Scope
                  of the Agreement and Partial Nullity | 
| This
                  Agreement contains the agreements reached by the Parties with respect
                  to
                  the matter that constitutes its objective, and it replaces all
                  prior
                  agreements or principles of agreement, verbal or written, that
                  might bind
                  the Parties in relation to this matter. | |
| If
                  a
                  competent Court or Authority declares all or part of any of the
                  nonessential clauses or subclauses of this Agreement null and void
                  or
                  unenforceable, it shall remain in effect except for the part declared
                  null
                  and void or unenforceable.  The Parties shall hold mutual
                  consultations and shall make their best efforts to agree to a valid
                  and
                  enforceable stipulation that constitutes a reasonable replacement
                  of the
                  null and void and unenforceable stipulation pursuant to the spirit
                  of this
                  Agreement. | |
| 12.6 | Modification
                  and Waiver | 
| This
                  Agreement may not be modified except if done so in writing signed
                  by the
                  Parties and with express and unequivocal mention of the modification
                  agreed. | |
| If
                  any of the Parties does not exercise any right that appertains
                  to it with
                  respect to a specific act or event in virtue of this Agreement,
                  such shall
                  not imply a waiver of such right and shall not in any manner prevent
                  the
                  subsequent exercise of such right with respect to other acts or
                  events
                  during its effective
                  period. | 
21
        13.         APPLICABLE
      LAW AND JURISDICTION
    13.1       Applicable
      Law
    All
      matters related to the formalization, validity, effectiveness, interpretation,
      and performance of this Agreement and the rights and obligations of the Parties
      shall be governed by the laws of the Kingdom of Spain.
    13.2       Jurisdiction
    The
      Parties expressly subject any disagreement or controversy that might arise
      on
      this Agreement or its execution, or which is related to it, to legal
      arbitration, pursuant to the regulation established by the rules and regulations
      of the International Chamber of Commerce (hereinafter, “CCI”),
      before (3) arbitrators appointed pursuant to the provisions of this Agreement,
      the Parties expressly waiving any other forum that might appertain to
      them.
    The
      Parties state that they know and accept the rules and regulations of the CCI,
      pursuant to whose rules, if applicable, the arbitration proceeding shall take
      place.
    The
      arbitration proceeding shall take place in the Spanish language in the city
      of
      New York (United States of America), in the place designated by the
      CCI.
    The
      legal
      arbitration shall be subject to Spanish law and three (3) arbitrators shall
      hear
      it.  Vendor and Purchaser shall appoint one (1) arbitrator each, the
      third of them appointed jointly by the arbitrators so appointed.  If
      the first two (2) arbitrators cannot agree on the selection of the third
      arbitrator, he shall be appointed pursuant to the current rules of the
      CCI.
    Likewise,
      the prosecution of the arbitration proceeding shall be subject to the rules
      and
      regulations of the CCI.
    The
      Parties shall request that the arbitrators include in the arbitration decision
      an express decision on the costs.  The decision on costs shall be
      proportional to the estimate of the claims of the Parties contained in the
      arbitration decision.
    The
      arbitration shall in all cases be final and the Parties are bound to perform
      and
      to voluntarily go through the provisions of the arbitration decision, within
      the
      timeframes set by common accord at the start of the arbitration
      proceeding.  On lack of agreement, the provisions of the CCI
      Regulation shall be applicable.
    Subsidiarily,
      and if necessary, especially in relation to the forced execution of the
      arbitration, the holding of the preparatory proceedings as well as the request
      for injunctions or measures of any other type, the Parties subject themselves,
      with express waiver of any other forum that might appertain to them, to the
      Courts and Tribunals of the city of Madrid.
    22
        AND
      IN
      WITNESS WHEREOF, the Parties sign this Agreement in a single copy in the place
      and on the date indicated in the heading which is delivered to the Notary for
      recording.
    | REPSOL
                    YPF,
                    S.A. | REPSOL
                    EXPLORACIÓN, S.A. | ||
| ▇▇.
                    ▇▇▇▇▇▇▇ ▇▇▇▇▇▇
                    Niubó | ▇▇.
▇▇▇▇▇▇▇
                    ▇▇▇▇▇▇▇▇▇-▇▇▇▇▇▇
                    ▇▇▇▇ ▇▇
                    ▇▇▇▇ | ||
| CAVEANT,
                    S.A. | REPSOL
                    YPF CAPITAL,
                    S.L. | ||
| ▇▇.
                    ▇▇▇▇▇▇▇▇ ▇▇▇▇▇▇▇
                    Mazarredo | ▇▇.
                    ▇▇▇▇▇▇▇▇ ▇▇▇▇▇▇▇
                    Mazarredo | ||
| ▇▇▇▇▇▇▇▇
                    ENERGÍA, S.A. | |||
| D.
                    ▇▇▇▇▇▇ ▇▇▇▇▇▇▇▇
                    ▇▇▇▇▇▇ | 
23
        LIST
      OF APPENDICES
    | Appendix
                E-IX | Term
                Loan | |
| Appendix
                E-X | Vendor’s
                Loan | |
| Appendix
                E-XI | Shareholders’
                Agreement | |
| Appendix
                1 | Definitions | |
| Appendix
                6.1 | Assignment
                of 2006 Dividend | |
| Appendix
                6.2 | Legend
                on “ADR” certificates | |
| Appendix
                7.3 | Shareholders’
                Meeting Agenda | |
| Appendix
                7.3-2nd | Corporate
                Bylaws Clauses to be
                Amended | 
1
        Appendix
      E-IX
    Term
      Loan
    [NOT
      FILED
      - REPSOL YPF, S.A. IS NOT A PARTY TO THIS AGREEMENT]
    1
        Appendix
      E-X
    Vendor’s
      Loan
    [FILED
      AS EXHIBIT 7.06]
    1
        Appendix
      E-XI
    Shareholders’
      Agreement
    [FILED
      AS EXHIBIT 7.02]
    1
        Appendix
      1
    Definitions
    | “Shares” | Means
                  together 58,603,606 common registered Class D shares of the Company
                  with a
                  par value of $ 10 each and 1 vote per share, as American Depositary
                  Shares (“ADS’s”) representing one Class D share each and represented
                  by American Depositary Receipts (“ADR’s”) issued by The Bank of New York
                  (hereinafter, the “Depository”) pursuant to the terms of the Deposit
                  Agreement between the Depository and the Company dated July 1,
                  1993 (the
                  “Deposit Agreement”), representing fourteen point ninety percent (14.90%)
                  of the capital stock of the Company (counting any uncapitalized
                  contribution, right to receive shares in the Company or any security
                  or
                  debt convertible into shares as if that right or conversion had
                  materialized), as well as all the political and capital rights
                  that
                  appertain thereto, including any option or preferred right of
                  subscription, the right to receive any dividend or distribution
                  corresponding thereto, either in shares, in kind, or in cash voted
                  and not
                  distributed to date (including the right to receive $10.76 pesos
                  per Share
                  corresponding to 14.9% of the amount designated by the meeting
                  held on
                  April 13, 2007 to constitute a reserve for the payment of future
                  dividends, once the distribution of such amount as a dividend has
                  been
                  approved by the Company’s Board of Directors on February 6, 2008 according
                  to the delegation made to the Board of Directors at the above mentioned
                  meeting) and, in addition, any other rights of any nature that
                  the Vendor
                  has as holder of the shares. | |
| “Necessary
                  Acts” | Means,
                  in relation to the results whose obtainment is required, all measures
                  that
                  are reasonable in business terms and which, within the legal authority
                  of
                  the Party in charge of performing those “Necessary Acts” is pertinent for
                  the purposes of obtaining such result.  Such measures include,
                  without limitation, (a) attending the corresponding meetings and
                  casting
                  votes with respect to all of the shares of which the Party obligated
                  to
                  perform the “Necessary Acts” owns; (b) instructing the directors appointed
                  by or at the proposal of such Party to convene meetings of the
                  board of
                  directors and/or meetings and to vote favorably in meetings of
                  the board
                  of directors and/or make entries into the corporate books and pertinent
                  registries, and to make presentations and/or notifications to Caja
                  de
                  Valores S.A., the CNV, the Buenos Aires Stock Exchange, the SEC,
                  the
                  Inspectorate General of Justice and any other authority or body
                  which is
                  necessary in order to obtain the result sought, and which are performed
                  pursuant hereto or to order that they be removed from their positions
                  if
                  they do not perform such acts or do not act pursuant hereto; (c)
                  preparing, executing, and/or signing documents, presentations and
                  notifications and/or registrations or similar acts that are required
                  in
                  order to reach the aforementioned result. | |
1
          | “Shareholders’
                  Agreement” | Means
                  the shareholders’ agreement signed by the Parties in a single act and
                  simultaneously with the signing of this Agreement, a copy of which
                  is
                  attached as Appendix E-XI. | |
| “Confidentiality
                  Agreement” | Means
                  the confidentiality agreement signed by the Vendor and Purchaser
                  on
                  February 19, 2007, together with the addendum thereto signed on
                  June [26],
                  2007. | |
| “CNDC” | Means
                  (i) the Argentine National Antitrust Commission and the Argentina
                  Department of Foreign Trade or the Department of Industry, Trade,
                  and
                  Mining, or (ii) the National Antitrust Tribunal, if such Tribunal
                  is
                  formed, or (ii) the public body or entity which, if applicable,
                  replaces
                  them in competence with respect to the matter pursuant to Argentina
                  laws. | |
| “Company” | Means
                  the Argentine company YPF, S.A., registered in the Superintendency
                  of
                  Corporations under Corporations Book 108, Number 404, Volume A,
                  with
                  principal executive offices at Avda. Presidente ▇▇▇▇▇ ▇▇▇▇▇ ▇▇▇▇ ▇▇▇,
                  ▇▇▇▇▇▇▇▇ ▇▇▇▇▇▇ ▇▇ ▇▇▇▇▇▇ ▇▇▇▇▇, ▇▇▇▇▇▇▇▇▇, and valid tax identification
                  code (CIF) 30-54668997-9. | |
| “Purchaser” | Means
                  the Spanish company, registered in the Commercial Registry of Madrid,
                  at
                  Volume 24588, Sheet 88, Page M-442504.  ▇▇▇▇▇▇▇▇ Energía, S.A.
                  has its principal executive offices at Plaza ▇▇▇▇▇ ▇▇▇▇ ▇▇▇▇▇▇▇
                  ▇, ▇▇▇▇▇
                  ▇▇▇▇▇▇▇,
                  ▇▇▇▇
                  ▇▇▇▇▇, ▇▇▇▇▇, ▇▇▇▇▇▇ and its tax identification code (CIF), ▇-▇▇▇▇▇▇▇▇,
                  is
                  current. | |
| “Condition
                  Subsequent” | Means
                  the condition subsequent established in Clause 5 of this
                  Agreement. | |
| “Agreement” | Means
                  this stock purchase and sale agreement signed by the Parties on
                  the date
                  that appears in the heading. | |
| “2006
                  Dividend” | The
                  amount resulting from the amount of $10.76 Argentine pesos per
                  share of
                  the Company, which distribution has been approved by the Company’s
                  Directory on February 6, 2008, according to the delegation made
                  to the
                  Directory at the meeting of April 13, 2007. | |
2
          | “Credit
                  Institutions” | Means
                  the credit institutions that sign the Term Loan with the Purchaser
                  and any
                  successor or assign thereof. | |
| “Corporate
                  Bylaws” | Means
                  the corporate bylaws of the Company in effect on the date of this
                  Agreement. | |
| “Liens” | Means
                  any attachment, pledge, tax, charge, usufruct, assessment, fiduciary
                  cession, guaranty or custody deposit, limitation or restriction
                  of free
                  transfer or of any nature, eviction claims, third party rights,
                  preferred
                  rights or options or any other third party right that affects free
                  ownership or free transfer. | |
| “Grupo
                  Repsol YPF” | Means,
                  collectively, Repsol YPF, Repsol Exploración, Caveant y Repsol YPF Capital
                  and any of them individually and without distinction. | |
| “Intercompany
                  Note” | Means
                  the debt the Seller has incurred with the Company in the amount
                  of US$
                  675.000.000,00 plus interest accrued and unpaid to the date of
                  the
                  cancellation. | |
| “Regulation” | Means
                  any law, regulation, resolution, administrative act, case law or
                  legislation | |
| “Party” | Means
                  either the Vendor or the Purchaser as the case may be. | |
| “Price” | Means
                  the price for the purchase and sale of the Shares determined as
                  stipulated
                  in Clause 4. | |
| “Subsidiaries” | Means
                  (a) those companies or legal entities whose capital stock and votes
                  are
                  more than 50%, under any title and for any reason, directly or
                  indirectly,
                  owned by or controlled by a legal person or (b) owned or controlled,
                  in
                  turn, by any company or entity owned or controlled by such legal
                  person. | |
| “Term
                  Loan” | Means
                  the finance agreement signed by the Purchaser with certain credit
                  institutions prior to the signing of this Agreement, a copy of
                  which is
                  attached as Appendix E-X. | |
| “Vendor” | Means
                  the Spanish company Repsol YPF, S.A., a company duly registered
                  in the
                  Commercial Registry of Madrid at Volume 3893, Sheet 175, Page
                  M-65289.  Repsol YPF has its principal executive offices at
                  ▇▇▇▇▇ ▇▇ ▇▇ ▇▇▇▇▇▇▇▇▇▇ ▇▇▇, ▇▇▇▇▇ ▇▇▇▇▇▇ and with tax identification
                  code
                  (CIF), ▇-▇▇▇▇▇▇▇▇, which is current. | |
| “20-F” | Means
                  the Form 20-F submitted by the Company to the SEC and corresponding
                  to the
                  fiscal year ended at December 31, 2006, or any other document sent
                  to the
                  SEC to clarify or supplement the aforementioned
                  20-F. | 
3
        Appendix
      6.1
    Assignment
      of 2006 Dividend
    [FILED
      AS EXHIBIT 7.08]
    8
        Appendix
      6.2
    ADR
      Legend
    [NOT
      FILED]
    1
        Appendix
      7.3
    Shareholders
      Meeting Agenda
    [NOT
      FILED]
    1
        Appendix
      7.3-2nd
    Corporate
      Bylaws Clauses to be Amended
    [NOT
      FILED]