• Shares Cogent Communications Group, Inc. Common Stock UNDERWRITING AGREEMENT

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Exhibit 1.1

• Shares

Cogent Communications Group, Inc.

Common Stock

May , 2005

▇▇▇▇▇▇ BROTHERS INC.
As Representative of the several
Underwriters named in Schedule 1 attached hereto,
c/▇ ▇▇▇▇▇▇ Brothers Inc.
▇▇▇ ▇▇▇▇▇▇▇ ▇▇▇▇▇▇
▇▇▇ ▇▇▇▇, ▇▇▇ ▇▇▇▇ ▇▇▇▇▇

Ladies and Gentlemen:

Cogent Communications Group, Inc., a Delaware corporation (the "Company"), proposes to sell • shares (the "Firm Stock") of the Company's common stock, par value $0.001 per share (the "Common Stock"). In addition, the Company proposes to grant to the underwriters (the "Underwriters") named in Schedule 1 attached to this agreement (this "Agreement") an option to purchase up to an additional • shares of the Common Stock on the terms set forth in Section 2 (the "Option Stock"). The Firm Stock and the Option Stock, if purchased, are hereinafter collectively called the "Stock." This is to confirm the agreement concerning the purchase of the Stock from the Company by the Underwriters.

1. Representations, Warranties and Agreements of the Company and the Principal Subsidiary. Each of the Company and Cogent Communications, Inc., a Delaware corporation and a wholly-owned subsidiary of the Company (the "Principal Subsidiary"), jointly and severally represents, warrants and agrees that:

(a) A registration statement on Form S-1 with respect to the Stock has (i) been prepared by the Company in conformity with the requirements of the Securities Act of 1933, as amended (the "Securities Act"), and the rules and regulations (the "Rules and Regulations") of the Securities and Exchange Commission (the "Commission") thereunder; (ii) been filed with the Commission under the Securities Act; and (iii) become effective under the Securities Act. Copies of such registration statement and each amendment thereto have been delivered by the Company to you as the Representative (the "Representative") of the Underwriters. As used in this Agreement, "Effective Time" means the date and the time as of which such registration statement, or the most recent post-effective amendment thereto, if any, was declared effective by the Commission; "Effective Date" means the date of the Effective Time; "Preliminary Prospectus" means each prospectus included in such registration statement, or amendments thereto, before such registration statement became effective under the Securities Act and any prospectus filed with the Commission by the Company with the consent of the Representative pursuant to Rule 424(a) of the Rules and Regulations; "Registration Statement" means such registration statement, as amended at the Effective Time, including any documents incorporated by reference therein at such time and all information contained in the final prospectus filed with the Commission pursuant to Rule 424(b) of the Rules and Regulations and deemed to be a part of the registration statement as of the Effective Time pursuant to paragraph (b) of Rule 430A of the Rules and Regulations; and "Prospectus" means such final prospectus, as first filed with the Commission pursuant to paragraph (1) or (4) of Rule 424(b) of the Rules and Regulations. Any reference herein to the term "Registration Statement" shall be deemed to include the abbreviated registration statement to register additional shares of Common Stock under Rule 462(b) of the Rules and Regulations (the "Rule 462 Registration Statement"). The Commission has not issued any order preventing or suspending the use of any Preliminary Prospectus or Prospectus or suspending the effectiveness of

the Registration Statement, and no proceeding for such purpose has been instituted or threatened by the Commission.

(b) The Registration Statement conformed in all material respects at the Effective Time and conforms in all material respects, and any post-effective amendment to the Registration Statement filed after the date hereof will conform in all material respects on the applicable effective date, to the requirements of the Securities Act and the Rules and Regulations. The Prospectus will conform in all material respects when filed with the Commission pursuant to Rule 424(b) and on the applicable Delivery Date (as defined in Section 4) to the requirements of the Securities Act and the Rules and Regulations. The Registration Statement, at the Effective Time, and the Prospectus, as of its date and on the applicable Delivery Date, do not and will not contain an untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein (in the case of the Prospectus, in the light of the circumstances under which they were made) not misleading; provided, that no representation or warranty is made as to information contained in or omitted from the Registration Statement or the Prospectus, or any amendments or supplements thereto, in reliance upon and in conformity with written information furnished to the Company through the Representative by or on behalf of any Underwriter specifically for inclusion therein, which information is specified in Section 8(e).

(c) The documents filed by the Company with the Commission pursuant to Section 13(a), 13(c), 14 or 15(d) of the Securities Exchange Act of 1934, as amended (the "Exchange Act"), and all documents incorporated by reference in the Registration Statement as exhibits thereto, when they became effective or when filed with the Commission, as the case may be, and on the applicable Delivery Date, conformed and will conform in all material respects to the requirements of the Securities Act or the Exchange Act, as applicable, and the rules and regulations of the Commission thereunder, and none of such documents contained or will contain an untrue statement of a material fact or omitted to state a material fact required to be stated therein or necessary to make the statements therein not misleading; and any further documents so filed or incorporated by reference in the Registration Statement, when filed with Commission and on the applicable Delivery Date, will conform in all material respects to the requirements of the Securities Act and the Exchange Act, as applicable, and the rules and regulations of the Commission thereunder and will not contain an untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein not misleading.

(d) Each of the Company and its subsidiaries (as defined in Section 16) has been duly organized, is validly existing and in good standing as a corporation or other business entity under the laws of its jurisdiction of organization and is duly qualified to do business and in good standing as a foreign corporation or other business entity in each jurisdiction in which its ownership or lease of property or the conduct of its businesses requires such qualification, except where the failure to be so qualified or in good standing, individually or in the aggregate, could not reasonably be expected to have a material adverse effect on the condition (financial or otherwise), results of operations, stockholders' equity, properties, business or prospects of the Company and its subsidiaries taken as a whole (a "Material Adverse Effect"). Each of the Company and its subsidiaries has all power and authority necessary to own or hold its properties and to conduct the businesses in which it is engaged. The Company does not own or control, directly or indirectly, any corporation, association or other entity other than the subsidiaries listed in Exhibit 21 to the Registration Statement. None of the subsidiaries of the Company (other than the Principal Subsidiary and Cogent Europe, S.à ▇.▇.) is a "significant subsidiary," as such term is defined in Rule 405 of the Rules and Regulations.

(e) The Company has an authorized capitalization as set forth in the Prospectus, and all of the issued shares of capital stock of the Company have been duly authorized and validly issued, are fully paid and non-assessable, conform to the description thereof contained in the Prospectus and were issued in compliance with federal and state securities laws and not in violation of any

preemptive right, resale right, right of first refusal or similar right. All of the Company's options, warrants and other rights to purchase or exchange any securities for shares of the Company's capital stock have been duly authorized and validly issued, conform to the description thereof contained in the Prospectus and were issued in compliance with federal and state securities laws. All of the issued shares of capital stock of each subsidiary of the Company have been duly authorized and validly issued, are fully paid and non-assessable and are owned directly or indirectly by the Company, other than as described in the Prospectus, free and clear of all liens, encumbrances, equities or claims, except for such liens, encumbrances, equities or claims as could not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect.

(f) The shares of the Stock to be issued and sold by the Company to the Underwriters hereunder have been duly authorized and, upon payment and delivery in accordance with this Agreement, will be validly issued, fully paid and non-assessable, will conform to the description thereof contained in the Prospectus, will be issued in compliance with federal and state securities laws and will be free of statutory and contractual preemptive rights, resale rights, rights of first refusal and similar rights.

(g) The Company and the Principal Subsidiary have all requisite corporate power and authority to execute, deliver and perform their obligations under this Agreement. This Agreement has been duly and validly authorized, executed and delivered by the Company and the Principal Subsidiary.

(h) The execution, delivery and performance of this Agreement by the Company and the Principal Subsidiary, the consummation of the transactions contemplated hereby and the application of the proceeds from the sale of Stock as described under "Use of Proceeds" in the Prospectus will not (i) conflict with or result in a breach or violation of any of the terms or provisions of, impose any lien, charge or encumbrance upon any property or assets of the Company and its subsidiaries, or constitute a default under, any indenture, mortgage, deed of trust, loan agreement, license or other agreement or instrument to which the Company or any of its subsidiaries is a party or by which the Company or any of its subsidiaries is bound or to which any of the property or assets of the Company or any of its subsidiaries is subject; (ii) result in any violation of the provisions of the charter or by-laws (or similar organizational documents) of the Company or any of its subsidiaries; or (iii) result in any violation of any statute or any order, rule or regulation of any court or governmental agency or body having jurisdiction over the Company or any of its subsidiaries or any of their properties or assets.

(i) Except for the registration of the Stock under the Securities Act and such consents, approvals, authorizations, registrations or qualifications as may be required under the Exchange Act and applicable state securities laws in connection with the purchase and sale of the Stock by the Underwriters, no consent, approval, authorization or order of, or filing or registration with, any court or governmental agency or body having jurisdiction over the Company or any of its subsidiaries or any of their properties or assets is required for the execution, delivery and performance of this Agreement by the Company, the consummation of the transactions contemplated hereby and the application of the proceeds from the sale of Stock as described under "Use of Proceeds" in the Prospectus.

(j) Other than as described in the Prospectus, there are no contracts, agreements or understandings between the Company and any person granting such person the right (other than rights which have been waived in writing or otherwise satisfied) to require the Company to file a registration statement under the Securities Act with respect to any securities of the Company owned or to be owned by such person or to require the Company to include such securities in the securities registered pursuant to the Registration Statement or in any securities being registered pursuant to any other registration statement filed by the Company under the Securities Act.

(k) The Company has not sold or issued any securities that would be integrated with the offering of the Stock contemplated by this Agreement pursuant to the Securities Act, the Rules and Regulations or the interpretations thereof by the Commission.

(l) Neither the Company nor any of its subsidiaries has sustained, since the date of the latest audited financial statements included in the Prospectus, any loss or interference with its business from fire, explosion, flood or other calamity, whether or not covered by insurance, or from any labor dispute or court or governmental action, order or decree, and since such date, there has not been any change in the capital stock or long-term debt of the Company or any of its subsidiaries or any adverse change, or any development involving a prospective adverse change, in or affecting the condition (financial or otherwise), results of operations, stockholders' equity, properties, management, business or prospects of the Company and its subsidiaries taken as a whole, in each case except as could not reasonably be expected to have a Material Adverse Effect.

(m) Since the date as of which information is given in the Prospectus and except as may otherwise be described in the Prospectus, the Company has not (i) incurred any liability or obligation, direct or contingent, which taken individually or in the aggregate, is material to the Company, other than liabilities and obligations that were incurred in the ordinary course of business, (ii) entered into any material transaction not in the ordinary course of business or (iii) declared or paid any dividend on its capital stock.

(n) The historical financial statements (including the related notes and supporting schedules) filed as part of the Registration Statement or included in the Prospectus comply as to form in all material respects with the requirements of Regulation S-X under the Securities Act and present fairly the financial condition, results of operations and cash flows of the entities purported to be shown thereby at the dates and for the periods indicated and have been prepared in conformity with accounting principles generally accepted in the United States applied on a consistent basis throughout the periods involved.

(o) The pro forma financial statements (including the related notes) filed as part of the Registration Statement or included in the Prospectus comply as to form in all material respects with the requirements of Regulation S-X under the Securities Act and present fairly the information shown therein. Such pro forma financial statements have been properly compiled on the bases described therein, the assumptions used in preparation thereof are reasonable and the adjustments used therein are appropriate to give effect to the transactions and circumstances referred to therein.

(p) Ernst & Young LLP, who have certified certain financial statements of the Company and its consolidated subsidiaries, whose report appears in the Prospectus and who have delivered the initial letter referred to in Section 7(g) hereof, are independent registered public accountants as required by the Securities Act and the Rules and Regulations.

(q) The Company and each of its subsidiaries have good and marketable title in fee simple to all real property and good and marketable title to all personal property owned by them, in each case free and clear of all liens, encumbrances and defects, except such as are described in the Prospectus or such as do not materially affect the value of such property and do not materially interfere with the use made and proposed to be made of such property by the Company and its subsidiaries; and all assets held under lease by the Company and its subsidiaries are held by them under valid, subsisting and enforceable leases, with such exceptions as do not materially interfere with the use made and proposed to be made of such assets by the Company and its subsidiaries.

(r) The Company and each of its subsidiaries carry, or are covered by, insurance from insurers of recognized financial responsibility in such amounts and covering such risks as is adequate for the conduct of their respective businesses and the value of their respective properties and as is customary for companies engaged in similar businesses in similar industries. All policies of insurance of the Company and its subsidiaries are in full force and effect; the Company and its

subsidiaries are in compliance with the terms of such policies in all material respects; and neither the Company nor any of its subsidiaries has received notice from any insurer or agent of such insurer that capital improvements or other expenditures are required or necessary to be made in order to continue such insurance.

(s) There are no legal or governmental proceedings pending to which the Company or any of its subsidiaries is a party or of which any property or assets of the Company or any of its subsidiaries is the subject that could reasonably be expected to have a Material Adverse Effect or could reasonably be expected to have a material adverse effect on the performance of this Agreement or the consummation of the transactions contemplated hereby; and to the Company's knowledge, no such proceedings are threatened or contemplated by governmental authorities or others.

(t) There are no contracts or other documents of a character required to be described in the Registration Statement or Prospectus or to be filed as exhibits to the Registration Statement or incorporated by reference therein that are not described and filed or incorporated by reference therein as required. Neither the Company nor any of its subsidiaries has knowledge that any other party to any such contract, agreement or arrangement has any intention not to render full performance as contemplated by the terms thereof.

(u) No relationship, direct or indirect, exists between or among the Company, on the one hand, and the directors, officers, stockholders, customers or suppliers of the Company, on the other hand, that is required to be described in the Prospectus which is not so described.

(v) No labor disturbance by the employees of the Company or its subsidiaries exists or, to the knowledge of the Company, is imminent that could reasonably be expected to have a Material Adverse Effect.

(w) The Company and each of its subsidiaries are in compliance in all material respects with all presently applicable provisions of the Employee Retirement Income Security Act of 1974, as amended, including the regulations and published interpretations thereunder ("ERISA"); no "reportable event" (as defined in ERISA) has occurred with respect to any "pension plan" (as defined in ERISA) for which the Company or any of its subsidiaries would have any liability; the Company and its subsidiaries have not incurred and do not expect to incur liability under (i) Title IV of ERISA with respect to termination of, or withdrawal from, any "pension plan" or (ii) Sections 412 or 4971 of the Internal Revenue Code of 1986, as amended, including the regulations and published interpretations thereunder (the "Code"); each "pension plan" for which the Company and its subsidiaries would have any liability that is intended to be qualified under Section 401(a) of the Code is so qualified in all material respects and nothing has occurred, whether by action or by failure to act, which would cause the loss of such qualification; and the Company and each of its subsidiaries have not incurred any unpaid liability to the Pension Benefit Guaranty Corporation (other than for payment of premiums in the ordinary course of business).

(x) The Company and each of its subsidiaries have filed all federal, state, local and foreign income and franchise tax returns required to be filed through the date hereof, subject to permitted extensions, and have paid all taxes due thereon, and no tax deficiency has been determined adversely to the Company or any of its subsidiaries, nor does the Company have any knowledge of any tax deficiency that could reasonably be expected to have a Material Adverse Effect.

(y) Neither the Company nor any of its subsidiaries (i) is in violation of its charter or by-laws (or similar organizational documents), (ii) is in default, and no event has occurred that, with notice or lapse of time or both, would constitute such a default, in the due performance or observance of any term, covenant or condition contained in any indenture, mortgage, deed of trust, loan agreement, license or other agreement or instrument to which it is a party or by which it is bound or to which any of its properties or assets is subject or (iii) is in violation of any statute or any order, rule or regulation of any court or governmental agency or body having jurisdiction over it or

its property or assets or has failed to obtain any license, permit, certificate, franchise or other governmental authorization or permit necessary to the ownership of its property or to the conduct of its business, except in the case of clauses (ii) and (iii), to the extent any such conflict, breach, violation or default could not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect.

(z) Neither the Company nor any subsidiary is, and as of the applicable Delivery Date and after giving effect to the offer and sale of the Stock and the application of the proceeds therefrom as described under "Use of Proceeds" in the Prospectus none of them will be, an "investment company" within the meaning of such term under the Investment Company Act of 1940, as amended, and the rules and regulations of the Commission thereunder.

(aa) Since the date of the most recent balance sheet of the Company and its consolidated subsidiaries reviewed or audited by Ernst & Young LLP and the audit committee of the board of directors of the Company, (i) the Company has not been advised of (A) any significant deficiencies in the design or operation of internal controls that could adversely affect the ability of the Company and each of its subsidiaries to record, process, summarize and report financial data, or any material weaknesses in internal controls and (B) any fraud, whether or not material, that involves management or other employees who have a significant role in the internal controls of the Company and each of its subsidiaries, and (ii) since that date, there have been no significant changes in internal controls or in other factors that could significantly affect internal controls, including any corrective actions with regard to significant deficiencies and material weaknesses.

(bb) The Company has not distributed and, prior to the later to occur of any Delivery Date and completion of the distribution of the Stock, will not distribute any offering material in connection with the offering and sale of the Stock other than the Preliminary Prospectus and the Prospectus.

(cc) The Company has not taken and will not take, directly or indirectly, any action designed to or that has constituted or that could reasonably be expected to cause or result in the stabilization or manipulation of the price of any security of the Company to facilitate the sale or resale of the shares of the Stock.

(dd) The Stock has been approved for listing, subject to official notice of issuance, on the American Stock Exchange.

(ee) The Company and each of its subsidiaries have such permits, licenses, patents, franchises, certificates of need and other approvals or authorizations of governmental or regulatory authorities ("Permits") as are necessary under applicable law to own their properties and conduct their businesses in the manner described in the Prospectus, except for any of the foregoing that could not reasonably be expected to have a Material Adverse Effect; each of the Company and its subsidiaries has fulfilled and performed all of its obligations with respect to the Permits, and no event has occurred that allows, or after notice or lapse of time would allow, revocation or termination thereof or results in any other impairment of the rights of the holder or any such Permits, except for any of the foregoing that could not reasonably be expected to have a Material Adverse Effect.

(ff) Except as described in the Prospectus, the Company and each of its subsidiaries own or possess adequate rights to use all material patents, patent applications, trademarks, service marks, trade names, trademark registrations, service ▇▇▇▇ registrations, copyrights, licenses and know-how (including trade secrets and other unpatented and/or unpatentable proprietary or confidential information, systems or procedures) necessary for the conduct of their respective businesses and, other than as described in the Prospectus, have no reason to believe that the conduct of their respective businesses will conflict with, and have not received any notice of any claim of conflict with, any such rights of others.

(gg) The Company and each of its subsidiaries are, and at all times prior were, (i) in compliance with any and all applicable federal, state, local and foreign laws, regulations, ordinances, rules, orders, judgments, decrees, permits or other legal requirements relating to the protection of human health and safety, the environment, natural resources or hazardous or toxic substances or wastes, pollutants or contaminants ("Environmental Laws"), which compliance includes obtaining, maintaining and complying with all permits and authorizations and approvals required by Environmental Laws to conduct their respective businesses and (ii) have not received notice of any actual or potential liability for the investigation or remediation of any disposal or release of hazardous or toxic substances or wastes, pollutants or contaminants, except in the case of clause (i) or (ii) where such non-compliance with or liability under Environmental Laws could not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect; and neither the Company nor any of its subsidiaries has been named as a "potentially responsible party" under the Comprehensive Environmental Response, Compensation and Liability Act of 1980, as amended, or any other similar Environmental Law, except with respect to any matters that, individually or in the aggregate, could not reasonably be expected to have a Material Adverse Effect. None of the Company and its subsidiaries (A) is a party to any proceeding under Environmental Laws in which a governmental authority is also a party, other than such proceedings regarding which it is believed no monetary penalties of $100,000 or more will be imposed, and (B) anticipates material capital expenditures relating to Environmental Laws.

(hh) The Principal Subsidiary directly, and not through its subsidiaries, owns in excess of 80% of the fair market value of the combined assets of the Company and its subsidiaries on a consolidated basis.

Any certificate signed by any officer of the Company and delivered to the Representative or counsel for the Underwriters in connection with the offering of the Stock shall be deemed a representation and warranty by the Company, as to matters covered thereby, to each Underwriter.

2. Purchase of the Stock by the Underwriters. On the basis of the representations and warranties contained in, and subject to the terms and conditions of, this Agreement, the Company agrees to sell • shares of the Firm Stock to the several Underwriters, and each of the Underwriters, severally and not jointly, agrees to purchase the number of shares of the Firm Stock set forth opposite that Underwriter's name in Schedule 1 hereto. The respective purchase obligations of the Underwriters with respect to the Firm Stock shall be rounded among the Underwriters to avoid fractional shares, as the Representative may determine.

In addition, the Company grants to the Underwriters an option to purchase up to • shares of Option Stock. Such option is granted for the purpose of covering over-allotments in the sale of Firm Stock and is exercisable as provided in Section 4 hereof. Each Underwriter agrees, severally and not jointly, to purchase the number of shares of Option Stock (subject to such adjustments to eliminate fractional shares as the Representative may determine) that bears the same proportion to the total number of shares of Option Stock to be sold on such Delivery Date as the number of shares of Firm Stock set forth in Schedule 1hereto opposite the name of such Underwriter bears to the total number of shares of Firm Stock.

The price of both the Firm Stock and any Option Stock purchased by the Underwriters shall be $ • per share.

The Company shall not be obligated to deliver any of the Firm Stock or Option Stock to be delivered on the applicable Delivery Date, except upon payment for all such Stock to be purchased on such Delivery Date as provided herein.

3. Offering of Stock by the Underwriters. Upon authorization by the Representative of the release of the Firm Stock, the several Underwriters propose to offer the Firm Stock for sale upon the terms and conditions set forth in the Prospectus.

4. Delivery of and Payment for the Stock. Delivery of and payment for the Firm Stock shall be made at 10:00 A.M., New York City time, on the third full business day following the date of this Agreement or at such other date or place as shall be determined by agreement between the Representative and the Company. This date and time are sometimes referred to as the "Initial Delivery Date." Delivery of the Firm Stock shall be made to the Representative for the account of each Underwriter against payment by the several Underwriters through the Representative of the respective aggregate purchase prices of the Firm Stock being sold by the Company to or upon the order of the Company by wire transfer in immediately available funds to the accounts specified by the Company. Time shall be of the essence, and delivery at the time specified pursuant to this Agreement is a further condition of the obligation of each Underwriter hereunder. Delivery of the Firm Stock shall be made through the facilities of The Depository Trust Company unless the Representative shall otherwise instruct.

The option granted in Section 2 will expire 30 days after the date of this Agreement and may be exercised in whole or from time to time in part by written notice being given to the Company by the Representative; provided that if such date falls on a day that is not a business day, the option granted in Section 2 will expire on the next succeeding business day. Such notice shall set forth the aggregate number of shares of Option Stock as to which the option is being exercised, the names in which the shares of Option Stock are to be registered, the denominations in which the shares of Option Stock are to be issued and the date and time, as determined by the Representative, when the shares of Option Stock are to be delivered; provided, however, that this date and time shall not be earlier than the Initial Delivery Date nor earlier than the second business day after the date on which the option shall have been exercised nor later than the fifth business day after the date on which the option shall have been exercised. The date and time the shares of Option Stock are delivered are sometimes referred to as an "Option Stock Delivery Date," and the Initial Delivery Date and any Option Stock Delivery Date are sometimes each referred to as a "Delivery Date."

Delivery of and payment for the Option Stock shall be made at the place specified in the first sentence of the first paragraph of this Section 4 (or at such other place as shall be determined by agreement between the Representative and the Company) at 10:00 A.M., New York City time, on such Option Stock Delivery Date. Delivery of the Firm Stock shall be made to the Representative for the account of each Underwriter against payment by the several Underwriters through the Representative of the respective aggregate purchase prices of the Firm Stock being sold by the Company to or upon the order of the Company by wire transfer in immediately available funds to the accounts specified by the Company. Time shall be of the essence, and delivery at the time specified pursuant to this Agreement is a further condition of the obligation of each Underwriter hereunder. Delivery of the Firm Stock shall be made through the facilities of The Depository Trust Company unless the Representative shall otherwise instruct.

5. Further Agreements of the Company. The Company agrees:

(a) To prepare the Prospectus in a form approved by the Representative and to file such Prospectus pursuant to Rule 424(b) under the Securities Act not later than Commission's close of business on the second business day following the execution and delivery of this Agreement; to make no further amendment or any supplement to the Registration Statement or to the Prospectus prior to the last Delivery Date except as permitted herein; to advise the Representative, promptly after it receives notice thereof, of the time when any amendment to the Registration Statement has been filed or becomes effective or any supplement to the Prospectus or any amended Prospectus has been filed and to furnish the Representative with copies thereof; to advise the Representative,

promptly after it receives notice thereof, of the issuance by the Commission of any stop order or of any order preventing or suspending the use of any Preliminary Prospectus or the Prospectus, of the suspension of the qualification of the Stock for offering or sale in any jurisdiction, of the initiation or threatening of any proceeding for any such purpose, or of any request by the Commission for the amending or supplementing of the Registration Statement or the Prospectus or for additional information; and, in the event of the issuance of any stop order or of any order preventing or suspending the use of any Preliminary Prospectus or the Prospectus or suspending any such qualification, to use promptly its best efforts to obtain its withdrawal;

(b) To furnish promptly to the Representative and to counsel for the Underwriters a signed copy of the Registration Statement as originally filed with the Commission, and each amendment thereto filed with the Commission, including all consents and exhibits filed therewith;

(c) To deliver promptly to the Representative such number of the following documents as the Representative shall reasonably request: (i) conformed copies of the Registration Statement as originally filed with the Commission and each amendment thereto (in each case excluding exhibits other than this Agreement and the computation of per share earnings) and (ii) each Preliminary Prospectus, the Prospectus and any amended or supplemented Prospectus; and, if the delivery of a prospectus is required at any time after the Effective Time in connection with the offering or sale of the Stock or any other securities relating thereto and if at such time any events shall have occurred as a result of which the Prospectus as then amended or supplemented would include an untrue statement of a material fact or omit to state any material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made when such Prospectus is delivered, not misleading, or, if for any other reason it shall be necessary to amend or supplement the Prospectus in order to comply with the Securities Act, to notify the Representative and, upon its request, to prepare and furnish without charge to each Underwriter and to any dealer in securities as many copies as the Representative may from time to time reasonably request of an amended or supplemented Prospectus that will correct such statement or omission or effect such compliance;

(d) To file promptly with the Commission any amendment to the Registration Statement or the Prospectus or any supplement to the Prospectus that may, in the judgment of the Company or the Representative, be required by the Securities Act or requested by the Commission;

(e) Prior to filing with the Commission any amendment to the Registration Statement or supplement to the Prospectus or any Prospectus pursuant to Rule 424(b) of the Rules and Regulations, to furnish a copy thereof to the Representative and counsel for the Underwriters and obtain the consent of the Representative to the filing;

(f) As soon as practicable after the Effective Date (it being understood that the Company shall have until at least 405 days or, if the fourth quarter following the fiscal quarter that includes the Effective Date is the last fiscal quarter of the Company's fiscal year, 425 days after the end of the Company's current fiscal quarter), to make generally available to the Company's security holders and to deliver to the Representative an earnings statement of the Company and its subsidiaries (which need not be audited) complying with Section 11(a) of the Securities Act and the Rules and Regulations (including, at the option of the Company, Rule 158);

(g) Promptly from time to time to take such action as the Representative may reasonably request to qualify the Stock for offering and sale under the securities laws of such jurisdictions as the Representative may request and to comply with such laws so as to permit the continuance of sales and dealings therein in such jurisdictions for as long as may be necessary to complete the distribution of the Stock; provided that in connection therewith the Company shall not be required to (i) qualify as a foreign corporation in any jurisdiction in which it would not otherwise be

required to so qualify, (ii) file a general consent to service of process in any such jurisdiction or (iii) subject itself to taxation in any jurisdiction in which it would not otherwise be subject;

(h) For a period of 180 days from the date of the Prospectus (the "Lock-Up Period"), not to, directly or indirectly, (1) offer for sale, sell, pledge or otherwise dispose of (or enter into any transaction or device that is designed to, or could be expected to, result in the disposition by any person at any time in the future of) any shares of Common Stock or securities convertible into or exchangeable for Common Stock (other than the Stock and shares issued pursuant to employee benefit plans, qualified stock option plans or other employee compensation plans existing on the date hereof or pursuant to currently outstanding options, warrants or rights), or sell or grant options, rights or warrants with respect to any shares of Common Stock or securities convertible into or exchangeable for Common Stock (other than the grant of options pursuant to option plans existing on the date hereof), (2) enter into any swap or other derivatives transaction that transfers to another, in whole or in part, any of the economic benefits or risks of ownership of such shares of Common Stock, whether any such transaction described in clause (1) or (2) above is to be settled by delivery of Common Stock or other securities, in cash or otherwise, (3) file or cause to be filed a registration statement with respect to any shares of Common Stock or securities convertible, exercisable or exchangeable into Common Stock or any other securities of the Company or (4) publicly disclose the intention to do any of the foregoing, in each case without the prior written consent of the Representative, on behalf of the Underwriters (the lock-up applicable to the Company as described in this paragraph being the "Company Lock-Up"), and to cause each officer and director of the Company set forth on Schedule 3 hereto to furnish to the Representative, prior to the Initial Delivery Date, a letter or letters, substantially in the form of Exhibit A hereto (the "Lock-Up Agreements"); provided, however, that the Company Lock-Up shall not apply to private unregistered issuances by the Company of shares of the Company's Common Stock or other capital stock as consideration in an acquisition of the assets or capital stock of a company or business;

Notwithstanding the foregoing paragraph, if (1) during the last 17 days of the Lock-Up Period, the Company issues an earnings release or material news or a material event relating to the Company occurs or (2) prior to the expiration of the Lock-Up Period, the Company announces that it will release earnings results during the 16-day period beginning on the last day of the Lock-Up Period, then the restrictions imposed in the preceding paragraph shall continue to apply until the expiration of the 18-day period beginning on the issuance of the earnings release or the announcement of the material news or the occurrence of the material event, unless the Representative, on behalf of the Underwriters, waives such extension in writing;

(i) To apply the net proceeds from the sale of the Stock being sold by the Company as set forth in the Prospectus;

6. Expenses. The Company agrees, whether or not the transactions contemplated by this Agreement are consummated or this Agreement is terminated, to pay all costs, expenses, fees and taxes incident to and in connection with (a) the authorization, issuance, sale and delivery of the Stock and any stamp duties or other taxes payable in that connection, and the preparation and printing of certificates for the Stock; (b) the preparation, printing and filing under the Securities Act of the Registration Statement and any amendments and exhibits thereto, any Preliminary Prospectus, the Prospectus and any amendment or supplement to the Prospectus; (c) the distribution of the Registration Statement as originally filed and each amendment thereto and any post-effective amendments thereof (including, in each case, exhibits), any Preliminary Prospectus, the Prospectus and any amendment or supplement to the Prospectus or any document incorporated by reference therein, all as provided in this Agreement; (d) the production and distribution of this Agreement, any supplemental agreement among Underwriters and any other related documents in connection with the offering, purchase, sale and delivery of the Stock; (e) any required review by the National Association

of Securities Dealers, Inc. (the "NASD") of the terms of sale of the Stock (including related fees and expenses of counsel to the Underwriters); (f) the listing of the Stock on the American Stock Exchange and/or any other exchange; (g) the qualification of the Stock under the securities laws of the several jurisdictions as provided in Section 5(g) and the preparation, printing and distribution of a Blue Sky Memorandum (including related fees and expenses of counsel to the Underwriters not to exceed, in the aggregate, $2,500); (h) food and lodging expenses for Company representatives and officers in connection with any "road show" undertaken in connection with the marketing of the Stock; and (i) all other costs and expenses incident to the performance of the obligations of the Company under this Agreement; provided that, except as provided in this Section 6 and in Section 11, the Underwriters shall pay their own costs and expenses, including but not limited to the costs and expenses of their counsel, the costs and expenses of the road show including airfare for road show participants and any aircraft chartered in connection therewith (other than the costs and expenses described in subsection (h) above which shall be paid by the Company), any transfer taxes on the Stock which they may sell and the expenses of advertising any offering of the Stock made by the Underwriters.

7. Conditions of Underwriters' Obligations. The respective obligations of the Underwriters hereunder are subject to the accuracy, when made and on each Delivery Date, of the representations and warranties of the Company and the Principal Subsidiary contained herein, to the performance by the Company of its obligations hereunder, and to each of the following additional terms and conditions:

(a) The Prospectus shall have been timely filed with the Commission in accordance with Section 5(a); no stop order suspending the effectiveness of the Registration Statement or preventing or suspending the use of the Prospectus shall have been issued and no proceeding for such purpose shall have been initiated or threatened by the Commission; and any request of the Commission for inclusion of additional information in the Registration Statement or the Prospectus or otherwise shall have been complied with.

(b) No Underwriter shall have discovered and disclosed to the Company on or prior to such Delivery Date that the Registration Statement or the Prospectus or any amendment or supplement thereto contains an untrue statement of a fact which, in the opinion of Mayer, Brown, ▇▇▇▇ & Maw LLP, counsel for the Underwriters, is material or omits to state a fact which, in the opinion of such counsel, is material and is required to be stated therein or is necessary to make the statements therein not misleading.

(c) All corporate proceedings and other legal matters incident to the authorization, form and validity of this Agreement, the Stock, the Registration Statement and the Prospectus, and all other legal matters relating to this Agreement and the transactions contemplated hereby shall be reasonably satisfactory in all material respects to counsel for the Underwriters, and the Company shall have furnished to such counsel all documents and information that they may reasonably request to enable them to pass upon such matters.

(d) ▇▇▇▇▇▇ & ▇▇▇▇▇▇▇ LLP shall have furnished to the Representative its written opinion, as counsel to the Company, addressed to the Underwriters and dated such Delivery Date, in form and substance reasonably satisfactory to the Representative, substantially in the form attached hereto as Exhibit B.

(e) The Representative shall have received from Mayer, Brown, ▇▇▇▇ & Maw LLP, counsel for the Underwriters, such opinion or opinions, dated such Delivery Date, with respect to the issuance and sale of the Stock, the Registration Statement, the Prospectus and other related matters as the Representative may reasonably require, and the Company shall have furnished to such counsel such documents as they reasonably request for the purpose of enabling them to pass upon such matters.

(f) At the time of execution of this Agreement, the Representative shall have received from Ernst & Young LLP a letter, in form and substance satisfactory to the Representative, addressed to the Underwriters and dated the date hereof (i) confirming that they are independent registered public accountants within the meaning of the Securities Act and are in compliance with the applicable requirements relating to the qualification of accountants under Rule 2-01 of Regulation S-X of the Commission, (ii) stating, as of the date hereof (or, with respect to matters involving changes or developments since the respective dates as of which specified financial information is given in the Prospectus, as of a date not more than three days prior to the date hereof), the conclusions and findings of such firm with respect to the financial information and other matters ordinarily covered by accountants' "comfort letters" to underwriters in connection with registered public offerings.

(g) With respect to the letter of Ernst & Young LLP referred to in the preceding paragraph and delivered to the Representative concurrently with the execution of this Agreement (the "initial letter"), the Company shall have furnished to the Representative a letter (the "bring-down letter") of such accountants, addressed to the Underwriters and dated such Delivery Date (i) confirming that they are independent registered public accountants within the meaning of the Securities Act and are in compliance with the applicable requirements relating to the qualification of accountants under Rule 2-01 of Regulation S-X of the Commission, (ii) stating, as of the date of the bring-down letter (or, with respect to matters involving changes or developments since the respective dates as of which specified financial information is given in the Prospectus, as of a date not more than three days prior to the date of the bring-down letter), the conclusions and findings of such firm with respect to the financial information and other matters covered by the initial letter and (iii) confirming in all material respects the conclusions and findings set forth in the initial letter.

(h) The Company shall have furnished to the Representative a certificate, dated such Delivery Date, of its Chief Executive Officer and its Chief Financial Officer stating that:

(i) The representations, warranties and agreements of the Company and the Principal Subsidiary in Section 1 are true and correct on and as of such Delivery Date, and the Company has complied with all its agreements contained herein and satisfied all the conditions on its part to be performed or satisfied hereunder at or prior to such Delivery Date;

(ii) No stop order suspending the effectiveness of the Registration Statement has been issued, and no proceedings for that purpose have been instituted or, to the knowledge of such officers, threatened;

(iii) They have carefully examined the Registration Statement and the Prospectus and, in their opinion, (A) the Registration Statement, as of the Effective Time, and the Prospectus, as of its date and as of such Delivery Date, did not and do not contain any untrue statement of a material fact and did not and do not omit to state a material fact required to be stated therein or necessary to make the statements therein (in the case of the Prospectus, in the light of the circumstances under which they were made) not misleading, and (B) since the Effective Time, no event has occurred that should have been set forth in an amendment to the Registration Statement or a supplement to the Prospectus that has not been so set forth; and

(i) (i) neither the Company nor any of its subsidiaries shall have sustained, since the date of the latest audited financial statements included in the Prospectus, any loss or interference with its business from fire, explosion, flood or other calamity, whether or not covered by insurance, or from any labor dispute or court or governmental action, order or decree or (ii) since such date there shall not have been any change in the capital stock or long-term debt of the Company or any of its subsidiaries or any change, or any development involving a prospective change, in or

affecting the condition (financial or otherwise), results of operations, stockholders' equity, properties, management, business or prospects of the Company and its subsidiaries taken as a whole, the effect of which, in any such case described in clause (i) or (ii), is, in the judgment of the Representative, so material and adverse as to make it impracticable or inadvisable to proceed with the public offering or the delivery of the Stock being delivered on such Delivery Date on the terms and in the manner contemplated in the Prospectus.

(j) Subsequent to the execution and delivery of this Agreement there shall not have occurred any of the following: (i) trading in securities generally on the New York Stock Exchange or the American Stock Exchange or in the over-the-counter market in the United States, or trading in any securities of the Company on any exchange in the United States or in the over-the-counter market in the United States, shall have been suspended or materially limited or the settlement of such trading generally shall have been materially disrupted or minimum prices shall have been established on any such exchange or such market by the Commission, by such exchange or by any other regulatory body or governmental authority having jurisdiction, (ii) a banking moratorium shall have been declared by federal or state authorities, (iii) the United States shall have become engaged in hostilities, there shall have been an escalation in hostilities involving the United States or there shall have been a declaration of a national emergency or war by the United States or (iv) there shall have occurred such a material adverse change in general economic, political or financial conditions, including, without limitation, as a result of terrorist activities after the date hereof (or the effect of international conditions on the financial markets in the United States shall be such), as to make it, in the judgment of the Representative, impracticable or inadvisable to proceed with the public offering or delivery of the Stock being delivered on such Delivery Date on the terms and in the manner contemplated in the Prospectus.

(k) The American Stock Exchange shall have approved the Stock for listing, subject only to official notice of issuance.

(l) The Lock-Up Agreements between the Representative and the officers, directors and stockholders of the Company set forth on Schedule 2, delivered to the Representative on or before the date of this Agreement, shall be in full force and effect on such Delivery Date.

All opinions, letters, evidence and certificates mentioned above or elsewhere in this Agreement shall be deemed to be in compliance with the provisions hereof only if they are in form and substance reasonably satisfactory to counsel for the Underwriters.

8. Indemnification and Contribution.

(a) The Company and the Principal Subsidiary shall jointly and severally indemnify and hold harmless each Underwriter, its directors, officers and employees and each person, if any, who controls any Underwriter within the meaning of Section 15 of the Securities Act, from and against any loss, claim, damage or liability, joint or several, or any action in respect thereof (including, but not limited to, any loss, claim, damage, liability or action relating to purchases and sales of Stock), to which that Underwriter, director, officer, employee or controlling person may become subject, under the Securities Act or otherwise, insofar as such loss, claim, damage, liability or action arises out of, or is based upon, (i) any untrue statement or alleged untrue statement of a material fact contained (A) in any Preliminary Prospectus, the Registration Statement or the Prospectus or in any amendment or supplement thereto or (B) in any materials or information provided to investors by, or with the written approval of, the Company in connection with the marketing of the offering of the Stock ("Marketing Materials"), including any road show or investor presentations made to investors by the Company (whether in person or electronically), (ii) the omission or alleged omission to state in any Preliminary Prospectus, the Registration Statement or the Prospectus, or in any amendment or supplement thereto or any Marketing Materials, any material fact required to be stated therein or necessary to make the statements therein not misleading: or (iii) any act or failure to act or any alleged act or failure to act by any Underwriter in connection with, or relating in any manner to, the Stock or the offering contemplated hereby, and which is included as part of or referred to in any loss, claim, damage, liability or action arising out of or based upon matters covered by clause (i) or (ii) above (provided that the Company and the Principal Subsidiary shall not be liable under this clause (iii) to the extent that it is determined in a final judgment by a court of competent jurisdiction that such loss, claim, damage, liability or action resulted directly from any such acts or failures to act undertaken or omitted to be taken by such Underwriter through its bad faith, gross negligence or willful misconduct), and shall reimburse each Underwriter and each such director, officer, employee or controlling person promptly upon demand for any legal or other expenses reasonably incurred by that Underwriter, director, officer, employee or controlling person in connection with investigating or defending or preparing to defend against any such loss, claim, damage, liability or action as such expenses are incurred; provided, however, that the Company and the Principal Subsidiary shall not be liable in any such case to the extent that any such loss, claim, damage, liability or action arises out of, or is based upon, any untrue statement or alleged untrue statement or omission or alleged omission made in any Preliminary Prospectus, the Registration Statement or the Prospectus, or in any such amendment or supplement, in reliance upon and in conformity with written information concerning such Underwriter furnished to the Company through the Representative by or on behalf of any Underwriter specifically for inclusion therein, which information consists solely of the information specified in Section 8(e); and provided further, that the foregoing indemnity agreement with respect to any Preliminary Prospectus shall not inure to the benefit of any Underwriter who it shall be established failed to deliver the Prospectus to the person asserting any losses, claims, damages, liabilities and judgments caused by any untrue statement or alleged untrue statement of a material fact or an omission or alleged omission to state a material fact required to be stated in such Preliminary Prospectus or necessary to make the statements in such Preliminary Prospectus not misleading, if (A) the Company shall have furnished copies of the Prospectus to the several Underwriters in the requisite quantity and sufficiently in advance of the Effective Date to permit proper delivery of the Prospectus to such person on or prior to the Effective Date; (B) such misstatement or omission or alleged misstatement or omission was identified in writing at such time to such Underwriter or its counsel and cured in the Prospectus and the Prospectus was required by law to be delivered to such person at or prior to the written confirmation of the sale of Stock to such person and (C) the timely delivery of the Prospectus to such person would have constituted a complete defense to the losses, claims, damages, liabilities and judgments asserted by such person. The foregoing indemnity agreement is in addition to any liability which the Company

may otherwise have to any Underwriter or to any director, officer, employee or controlling person of that Underwriter.

(b) Each Underwriter, severally and not jointly, shall indemnify and hold harmless the Company, its directors, officers and employees, and each person, if any, who controls the Company within the meaning of Section 15 of the Securities Act, from and against any loss, claim, damage or liability, joint or several, or any action in respect thereof, to which the Company or any such director, officer, employee or controlling person may become subject, under the Securities Act or otherwise, insofar as such loss, claim, damage, liability or action arises out of, or is based upon, (i) any untrue statement or alleged untrue statement of a material fact contained in any Preliminary Prospectus, the Registration Statement or the Prospectus or in any amendment or supplement thereto, or any Marketing Materials, or (ii) the omission or alleged omission to state in any Preliminary Prospectus, the Registration Statement or the Prospectus, or in any amendment or supplement thereto, or any Marketing Materials, any material fact required to be stated therein or necessary to make the statements therein not misleading, but in each case only to the extent that the untrue statement or alleged untrue statement or omission or alleged omission was made in reliance upon and in conformity with written information concerning such Underwriter furnished to the Company through the Representative by or on behalf of that Underwriter specifically for inclusion therein, which information is limited to the information set forth in Section 8(e) and shall reimburse the Company and any such director, officer or controlling person for any legal or other expenses reasonably incurred by the Company or any such director, officer or controlling person in connection with investigating or defending or preparing to defend against any such loss, claim, damage, liability or action as such expenses are incurred. The foregoing indemnity agreement is in addition to any liability that any Underwriter may otherwise have to the Company or any such director, officer, employee or controlling person.

(c) Promptly after receipt by an indemnified party under this Section 8 of notice of any claim or the commencement of any action, the indemnified party shall, if a claim in respect thereof is to be made against the indemnifying party under this Section 8, notify the indemnifying party in writing of the claim or the commencement of that action; provided, however, that the failure to notify the indemnifying party shall not relieve it from any liability which it may have under this Section 8 except to the extent it has been materially prejudiced by such failure and, provided, further, that the failure to notify the indemnifying party shall not relieve it from any liability which it may have to an indemnified party otherwise than under this Section 8. If any such claim or action shall be brought against an indemnified party, and it shall notify the indemnifying party thereof, the indemnifying party shall be entitled to participate therein and, to the extent that it wishes, jointly with any other similarly notified indemnifying party, to assume the defense thereof with counsel reasonably satisfactory to the indemnified party. After notice from the indemnifying party to the indemnified party of its election to assume the defense of such claim or action, the indemnifying party shall not be liable to the indemnified party under this Section 8 for any legal or other expenses subsequently incurred by the indemnified party in connection with the defense thereof other than reasonable costs of investigation; provided, however, that the Representative shall have the right to employ counsel to represent jointly the Representative and those other Underwriters and their respective directors, officers, employees and controlling persons who may be subject to liability arising out of any claim in respect of which indemnity may be sought by the Underwriters against the Company under this Section 8 if (i) the Company and the Underwriters shall have so mutually agreed; (ii) the Company has failed within a reasonable time to retain counsel reasonably satisfactory to the Underwriters; (iii) the Underwriters and their respective directors, officers, employees and controlling persons shall have reasonably concluded that there may be legal defenses available to them that are different from or in addition to those available to the Company; or (iv) the named parties in any such proceeding (including any impleaded parties) include both the Underwriters or their respective directors, officers, employees or controlling

persons, on the one hand, and the Company, on the other hand, and representation of both sets of parties by the same counsel would be inappropriate due to actual or potential differing interests between them, and in any such event the fees and expenses of such separate counsel shall be paid by the Company. No indemnifying party shall (i) without the prior written consent of the indemnified parties (which consent shall not be unreasonably withheld), settle or compromise or consent to the entry of any judgment with respect to any pending or threatened claim, action, suit or proceeding in respect of which indemnification or contribution may be sought hereunder (whether or not the indemnified parties are actual or potential parties to such claim or action) unless such settlement, compromise or consent includes an unconditional release of each indemnified party from all liability arising out of such claim, action, suit or proceeding and does not include any findings of fact or admissions of fault or culpability as to the indemnified party, or (ii) be liable for any settlement of any such action effected without its written consent (which consent shall not be unreasonably withheld), but if settled with the consent of the indemnifying party or if there be a final judgment of the plaintiff in any such action, the indemnifying party agrees to indemnify and hold harmless any indemnified party from and against any loss or liability by reason of such settlement or judgment.

(d) If the indemnification provided for in this Section 8 shall for any reason be unavailable to or insufficient to hold harmless an indemnified party under Section 8(a) or 8(b) in respect of any loss, claim, damage or liability, or any action in respect thereof, referred to therein, then each indemnifying party shall, in lieu of indemnifying such indemnified party, contribute to the amount paid or payable by such indemnified party as a result of such loss, claim, damage or liability, or action in respect thereof, (i) in such proportion as shall be appropriate to reflect the relative benefits received by the Company and the Principal Subsidiary, on the one hand, and the Underwriters, on the other, from the offering of the Stock or (ii) if the allocation provided by clause (i) above is not permitted by applicable law, in such proportion as is appropriate to reflect not only the relative benefits referred to in clause (i) above but also the relative fault of the Company and the Principal Subsidiary, on the one hand, and the Underwriters, on the other, with respect to the statements or omissions that resulted in such loss, claim, damage or liability, or action in respect thereof, as well as any other relevant equitable considerations. The relative benefits received by the Company and the Principal Subsidiary, on the one hand, and the Underwriters, on the other, with respect to such offering shall be deemed to be in the same proportion as the total net proceeds from the offering of the Stock purchased under this Agreement (before deducting expenses) received by the Company, as set forth in the table on the cover page of the Prospectus, on the one hand, and the total underwriting discounts and commissions received by the Underwriters with respect to the shares of the Stock purchased under this Agreement, as set forth in the table on the cover page of the Prospectus, on the other hand, bear to the total gross proceeds from the offering of the shares of the Stock under this Agreement, as set forth in the table on the cover page of the Prospectus. The relative fault shall be determined by reference to whether the untrue or alleged untrue statement of a material fact or omission or alleged omission to state a material fact relates to information supplied by the Company, the Principal Subsidiary or the Underwriters, the intent of the parties and their relative knowledge, access to information and opportunity to correct or prevent such statement or omission. The Company, the Principal Subsidiary and the Underwriters agree that it would not be just and equitable if contributions pursuant to this Section 8(d) were to be determined by pro rata allocation (even if the Underwriters were treated as one entity for such purpose) or by any other method of allocation which does not take into account the equitable considerations referred to herein. The amount paid or payable by an indemnified party as a result of the loss, claim, damage or liability, or action in respect thereof, referred to above in this Section 8(d) shall be deemed to include, for purposes of this Section 8(d), any legal or other expenses reasonably incurred by such indemnified party in connection with investigating or defending any such action or claim.

Notwithstanding the provisions of this Section 8(d), no Underwriter shall be required to contribute any amount in excess of the amount by which the total price at which the Stock underwritten by it and distributed to the public was offered to the public exceeds the amount of any damages which such Underwriter has otherwise paid or become liable to pay by reason of any untrue or alleged untrue statement or omission or alleged omission. No person guilty of fraudulent misrepresentation (within the meaning of Section 11(f) of the Securities Act) shall be entitled to contribution from any person who was not guilty of such fraudulent misrepresentation. The Underwriters' obligations to contribute as provided in this Section 8(d) are several in proportion to their respective underwriting obligations and not joint.

(e) The Underwriters severally confirm and the Company acknowledges and agrees that the statements with respect to the public offering of the Stock by the Underwriters set forth on the cover page of, and the concession and reallowance figures and the paragraph relating to stabilization by the Underwriters appearing under the caption "Underwriting" in, the Prospectus are correct and constitute the only information concerning such Underwriters furnished in writing to the Company by or on behalf of the Underwriters specifically for inclusion in the Registration Statement and the Prospectus.

9. Defaulting Underwriters. If, on any Delivery Date, any Underwriter defaults in the performance of its obligations under this Agreement, the remaining non-defaulting Underwriters shall be obligated to purchase the Stock that the defaulting Underwriter agreed but failed to purchase on such Delivery Date in the respective proportions which the number of shares of the Firm Stock set forth opposite the name of each remaining non-defaulting Underwriter in Schedule 1 hereto bears to the total number of shares of the Firm Stock set forth opposite the names of all the remaining non-defaulting Underwriters in Schedule 1 hereto; provided, however, that the remaining non-defaulting Underwriters shall not be obligated to purchase any of the Stock on such Delivery Date if the total number of shares of the Stock which the defaulting Underwriter or Underwriters agreed but failed to purchase on such date exceeds 9.09% of the total number of shares of the Stock to be purchased on such Delivery Date, and any remaining non-defaulting Underwriter shall not be obligated to purchase more than 110% of the number of shares of the Stock which it agreed to purchase on such Delivery Date pursuant to the terms of Section 2. If the foregoing maximums are exceeded, the remaining non-defaulting Underwriters, or those other underwriters satisfactory to the Representative who so agree, shall have the right, but shall not be obligated, to purchase, in such proportion as may be agreed upon among them, all the Stock to be purchased on such Delivery Date. If the remaining Underwriters or other underwriters satisfactory to the Representative do not elect to purchase the shares that the defaulting Underwriter or Underwriters agreed but failed to purchase on such Delivery Date, this Agreement (or, with respect to any Option Stock Delivery Date, the obligation of the Underwriters to purchase, and of the Company to sell, the Option Stock) shall terminate without liability on the part of any non-defaulting Underwriter, the Company or the Principal Subsidiary, except that the Company will continue to be liable for the payment of expenses to the extent set forth in Sections 6 and 11. As used in this Agreement, the term "Underwriter" includes, for all purposes of this Agreement unless the context requires otherwise, any party not listed in Schedule 1 hereto that, pursuant to this Section 9, purchases Stock that a defaulting Underwriter agreed but failed to purchase.

Nothing contained herein shall relieve a defaulting Underwriter of any liability it may have to the Company and the Principal Subsidiary for damages caused by its default. If other Underwriters are obligated or agree to purchase the Stock of a defaulting or withdrawing Underwriter, either the Representative or the Company may postpone the Delivery Date for up to seven full business days in order to effect any changes that in the opinion of counsel for the Company or counsel for the Underwriters may be necessary in the Registration Statement, the Prospectus or in any other document or arrangement.

10. Termination. The obligations of the Underwriters hereunder may be terminated by the Representative by notice given to and received by the Company prior to delivery of and payment for the Firm Stock if, prior to that time, any of the events described in Sections 7(i), 7(j) and 7(k) shall have occurred (or not occurred, as the case may be) or if the Underwriters shall decline to purchase the Stock for any reason permitted under this Agreement.

11. Reimbursement of Underwriters' Expenses. If the Company shall fail to tender the Stock for delivery to the Underwriters by reason of any failure, refusal or inability on the part of the Company to perform any agreement on its part to be performed, or because any other condition of the Underwriters' obligations hereunder required to be fulfilled by the Company is not fulfilled, the Company will reimburse the Underwriters for all reasonable out-of-pocket expenses (including fees and disbursements of counsel) incurred by the Underwriters in connection with this Agreement and the proposed purchase of the Stock, and upon demand the Company shall pay the full amount thereof to the Representative. If this Agreement is terminated pursuant to Section 9 by reason of the default of one or more Underwriters, the Company shall not be obligated to reimburse any defaulting Underwriter on account of those expenses.

12. Research Independence. In addition, the Company acknowledges that the Underwriters' research analysts and research departments are required to be independent from their respective investment banking divisions and are subject to certain regulations and internal policies, and that such Underwriters' research analysts may hold and make statements or investment recommendations and/or publish research reports with respect to the Company and/or the offering that differ from the views of its investment bankers. The Company hereby waives and releases, to the fullest extent permitted by law, any claims that the Company may have against the Underwriters with respect to any conflict of interest that may arise from the fact that the views expressed by their independent research analysts and research departments may be different from or inconsistent with the views or advice communicated to the Company by such Underwriters' investment banking divisions. The Company acknowledges that each of the Underwriters is a full service securities firm and as such from time to time, subject to applicable securities laws, may effect transactions for its own account or the account of its customers and hold long or short positions in debt or equity securities of the companies which may be the subject of the transactions contemplated by this Agreement.

13. Notices, Etc. All statements, requests, notices and agreements hereunder shall be in writing, and:

(a) if to the Underwriters, shall be delivered or sent by mail, telex or facsimile transmission to ▇▇▇▇▇▇ Brothers Inc., ▇▇▇ ▇▇▇▇▇▇▇ ▇▇▇▇▇▇, ▇▇▇ ▇▇▇▇, ▇▇▇ ▇▇▇▇ ▇▇▇▇▇, Attention: Syndicate Department (Fax: ▇▇▇-▇▇▇-▇▇▇▇), with a copy, in the case of any notice pursuant to Section 8(c), to the Director of Litigation, Office of the General Counsel, ▇▇▇▇▇▇ Brothers Inc., ▇▇▇ ▇▇▇▇ ▇▇▇▇▇▇, ▇▇^▇▇ ▇▇▇▇▇, ▇▇▇ ▇▇▇▇, ▇▇▇ ▇▇▇▇ ▇▇▇▇▇ (Fax: ▇▇▇-▇▇▇-▇▇▇▇); and

(b) if to the Company or the Principal Subsidiary, shall be delivered or sent by mail, telex or facsimile transmission to the address of the Company set forth in the Registration Statement, Attention: ▇▇▇▇▇▇ ▇. ▇▇▇▇▇, ▇▇. (Fax: ▇▇▇-▇▇▇-▇▇▇▇);

provided, however, that any notice to an Underwriter pursuant to Section 8(c) shall be delivered or sent by mail, telex or facsimile transmission to such Underwriter at its address set forth in its acceptance telex to the Representative, which address will be supplied to any other party hereto by the Representative upon request. Any such statements, requests, notices or agreements shall take effect at the time of receipt thereof. The Company shall be entitled to act and rely upon any request, consent, notice or agreement given or made on behalf of the Underwriters by ▇▇▇▇▇▇ Brothers Inc.

14. Persons Entitled to Benefit of Agreement. This Agreement shall inure to the benefit of and be binding upon the Underwriters, the Company, the Principal Subsidiary and their respective successors.

This Agreement and the terms and provisions hereof are for the sole benefit of only those persons, except that (A) the representations, warranties, indemnities and agreements of the Company and the Principal Subsidiary contained in this Agreement shall also be deemed to be for the benefit of the directors, officers and employees of the Underwriters and each person or persons, if any, who control any Underwriter within the meaning of Section 15 of the Securities Act and (B) the indemnity agreement of the Underwriters contained in Section 8(b) of this Agreement shall be deemed to be for the benefit of the directors of the Company, the officers of the Company who have signed the Registration Statement and any person controlling the Company within the meaning of Section 15 of the Securities Act. Nothing in this Agreement is intended or shall be construed to give any person, other than the persons referred to in this Section 14, any legal or equitable right, remedy or claim under or in respect of this Agreement or any provision contained herein.

15. Survival. The respective indemnities, representations, warranties and agreements of the Company, the Principal Subsidiary and the Underwriters contained in this Agreement or made by or on behalf on them, respectively, pursuant to this Agreement, shall survive the delivery of and payment for the Stock and shall remain in full force and effect, regardless of any investigation made by or on behalf of any of them or any person controlling any of them.

16. Definition of the Terms "Business Day" and "Subsidiary". For purposes of this Agreement, (a) "business day" means each Monday, Tuesday, Wednesday, Thursday or Friday that is not a day on which banking institutions in New York are generally authorized or obligated by law or executive order to close and (b) "subsidiary" has the meaning set forth in Rule 405 of the Rules and Regulations.

17. Governing Law. This Agreement shall be governed by and construed in accordance with the laws of the State of New York.

18. Counterparts. This Agreement may be executed in one or more counterparts and, if executed in more than one counterpart, the executed counterparts shall each be deemed to be an original but all such counterparts shall together constitute one and the same instrument.

19. Headings. The headings herein are inserted for convenience of reference only and are not intended to be part of, or to affect the meaning or interpretation of, this Agreement.

If the foregoing correctly sets forth the agreement between the Company, the Principal Subsidiary and the Underwriters, please indicate your acceptance in the space provided for that purpose below.

		Very truly yours,
		COGENT COMMUNICATIONS GROUP, INC.
		By:
				Name:
				Title:
		COGENT COMMUNICATIONS, INC.
		By:
				Name:
				Title:

Accepted:
▇▇▇▇▇▇ BROTHERS INC.
For itself and as Representative of the several Underwriters named in Schedule 1 hereto
By:		Authorized Representative

SCHEDULE 1

Underwriters		Number of Shares of Firm Stock
▇▇▇▇▇▇ Brothers Inc.
▇▇▇▇▇▇ ▇▇▇▇▇▇ Partners LLC
CIBC World Markets Corp.
Friedman, Billings, ▇▇▇▇▇▇ & Co., Inc.

Total

B-1

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Exhibit 1.1

UNDERWRITING AGREEMENT
SCHEDULE 1

• Shares Cogent Communications Group, Inc. Common Stock UNDERWRITING AGREEMENT

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