Exhibit 1.1

EXECUTION COPY

7,000,000 Shares

Cogent Communications Group, Inc.

Common Stock

UNDERWRITING AGREEMENT

November 9, 2006

RBC CAPITAL MARKETS CORPORATION
One Liberty Plaza, 6th floor
New York, New York 10006

Ladies and Gentlemen:

Certain stockholders named in Schedule 2 attached hereto (the “Selling Stockholders”), propose to sell an aggregate of 7,000,000 shares (the “Stock”) of the common stock, par value $0.001 per share (the “Common Stock”) of Cogent Communications Group, Inc. (the “Company”).  This is to confirm the agreement (the “Agreement”) concerning the purchase of the Stock from the Selling Stockholders by RBC Capital Markets Corporation (the “Underwriter”).

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-3 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 Underwriter.  As used in this Agreement:

(i)            “Applicable Time” means 9:00 a.m. (New York City time) on November 9, 2006;

(ii)           “Effective Date” means any date as of which any part of such registration statement relating to the Stock became, or is deemed to have become, effective under the Securities Act in accordance with the Rules and Regulations;

(iii)          “Issuer Free Writing Prospectus” means each “free writing prospectus” (as defined in Rule 405 of the Rules and Regulations) prepared by or on behalf of the Company or used or referred to by the Company in connection with the offering of the Stock:

(iv)          “Preliminary Prospectus” means any preliminary prospectus relating to the Stock included in such registration statement or filed with the Commission pursuant to Rule 424(b) of the Rules and Regulations, including any preliminary prospectus supplement relating to the Stock;

(v)           “Pricing Disclosure Package” means, as of the Applicable Time, the most recent Preliminary Prospectus, together with each Issuer Free Writing Prospectus filed or used by the Company on or before the Applicable Time, other than a road show that is an Issuer Free Writing Prospectus under Rule 433 of the Rules and Regulations;

(vi)          “Prospectus” means the final prospectus relating to the Stock, including any prospectus supplement thereto relating to the Stock, as filed with the Commission pursuant to Rule 424(b) of the Rules and Regulations; and

(vii)         “Registration Statement” means, collectively, the various parts of such registration statement, each as amended as of the Effective Date for such part, including any Preliminary Prospectus and the Prospectus and all exhibits to such registration statement.

Any reference to any Preliminary Prospectus or the Prospectus shall be deemed to refer to and include any documents incorporated by reference therein pursuant to Form S-3 under the Securities Act as of the date of such Preliminary Prospectus or the Prospectus, as the case may be.  Any reference to the “most recent Preliminary Prospectus” shall be deemed to refer to the latest Preliminary Prospectus included in the Registration Statement or filed pursuant to Rule 424(b) prior to or on the date hereof (including, for purposes hereof, any documents incorporated by reference therein prior to or on the date hereof).  Any reference to any amendment or supplement to any Preliminary Prospectus or the Prospectus shall be deemed to refer to and include any document filed under the Securities Exchange Act of 1934, as amended (the “Exchange Act”), after the date of such Preliminary Prospectus or the Prospectus, as the case may be, and incorporated by reference in such Preliminary Prospectus or the Prospectus, as the case may be; and any reference to any amendment to the Registration Statement shall be deemed to include any annual report of the Company on Form 10-K filed with the Commission pursuant to Section 13(a) or 15(d) of the Exchange Act after the Effective Date that is incorporated by reference in the 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.

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(b)           The Company was not at the time of initial filing of the Registration Statement and at the earliest time thereafter that the Company or another offering participant made a bona fide offer (within the meaning of Rule 164(h)(2) of the Rules and Regulations) of the Stock, is not on the date hereof and will not be on the applicable Delivery Date (as defined below) an “ineligible issuer” (as defined in Rule 405 of the Rules and Regulations).  The Company has been since the time of initial filing of the Registration Statement and continues to be eligible to use Form S-3 for the offering of the Stock.

(c)           The Registration Statement conformed and will conform in all material respects on the Effective Date and on the applicable Delivery Date, and any amendment to the Registration Statement filed after the date hereof will conform in all material respects when filed, to the requirements of the Securities Act and the Rules and Regulations.  The Preliminary Prospectus conformed, and the Prospectus will conform, in all material respects when filed with the Commission pursuant to Rule 424(b) and on the applicable Delivery Date to the requirements of the Securities Act and the Rules and Regulations.  The documents incorporated by reference in any Preliminary Prospectus or the Prospectus conformed, and any further documents so incorporated will conform, when filed with the Commission, in all material respects to the requirements of the Exchange Act or the Securities Act, as applicable, and the rules and regulations of the Commission thereunder.  The Registration Statement, at the Effective Date, did not, and the Prospectus, as of its date and on the applicable Delivery Date, 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 in reliance upon and in conformity with written information furnished to the Company by or on behalf of the Underwriter specifically for inclusion therein, which information is specified in Section 10(f).

(d)           The documents incorporated by reference in any Preliminary Prospectus or the Prospectus did not, and any further documents filed and incorporated by reference therein will not, when filed with the Commission, 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 light of the circumstances under which they were made, not misleading.

(e)           The Pricing Disclosure Package did not, as of the Applicable Time, 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 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 Pricing Disclosure Package in reliance upon and in conformity with written information furnished to the Company by or on behalf of the Underwriter specifically for inclusion therein, which information is specified in Section 10(f).

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(f)            Each Issuer Free Writing Prospectus (including, without limitation, any road show that is a free writing prospectus under Rule 433), when considered together with the Pricing Disclosure Package as of the Applicable Time, did 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 light of the circumstances under which they were made, not misleading.

(g)           Each Issuer Free Writing Prospectus conformed or will conform in all material respects to the requirements of the Securities Act and the Rules and Regulations on the date of first use, and the Company has complied with any filing requirements applicable to such Issuer Free Writing Prospectus pursuant to the Rules and Regulations. The Company has not made any offer relating to the Stock that would constitute an Issuer Free Writing Prospectus without the prior written consent of the Underwriter.  The Company has retained in accordance with the Rules and Regulations all Issuer Free Writing Prospectuses that were not required to be filed pursuant to the Rules and Regulations.

(h)           Each of the Company and its subsidiaries (as defined in Section 19) 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 21.1 to the Company’s Annual Report on Form 10-K for the year ended December 31, 2005.  None of the subsidiaries of the Company (other than the Principal Subsidiary and Cogent Europe, SARL) is a “significant subsidiary,” as such term is defined in Rule 405 of the Rules and Regulations.

(i)            The Company has an authorized capitalization as set forth in each of the most recent Preliminary Prospectus and 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 each of the most recent Preliminary Prospectus and 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 each of the most recent Preliminary Prospectus and 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

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issued, are fully paid and non-assessable and are owned directly or indirectly by the Company, other than as described in the most recent Preliminary Prospectus and 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.

(j)            The shares of Stock to be sold by the Selling Stockholders will be sold in compliance with federal and state securities laws.

(k)           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.

(l)            The execution, delivery and performance of this Agreement by the Company and the Principal Subsidiary and the consummation of the transactions contemplated hereby 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.

(m)          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 Underwriter, 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 and the Principal Subsidiary and the consummation of the transactions contemplated hereby.

(n)           Other than as described in the most recent Preliminary 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.

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(o)           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.

(p)           Neither the Company nor any of its subsidiaries has sustained, since the date of the latest audited financial statements included or incorporated by reference in the most recent Preliminary 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, in the aggregate, reasonably be expected to have a Material Adverse Effect.

(q)           Since the date as of which information is given in the most recent Preliminary Prospectus and except as may otherwise be described in the most recent Preliminary 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.

(r)            The historical financial statements (including the related notes and supporting schedules) included or incorporated by reference in the most recent Preliminary 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.

(s)           The pro forma financial information included or incorporated by reference in the most recent Preliminary Prospectus complies as to form in all material respects with the requirements of Regulation S-X under the Securities Act and presents fairly the information shown therein.  Such pro forma financial information has 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.

(t)            Ernst & Young LLP, who have certified certain financial statements of the Company and its consolidated subsidiaries, whose report appears in the most recent Preliminary Prospectus or is incorporated by reference therein and who have delivered the initial letter referred to in Section 9(i) hereof, are independent registered public accountants as required by the Securities Act and the Rules and Regulations.

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(u)           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 most recent Preliminary 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.

(v)           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.

(w)          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, in the aggregate, reasonably be expected to have a Material Adverse Effect or could, in the aggregate, 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.

(x)            There are no contracts or other documents of a character required to be described in the Registration Statement or the most recent Preliminary 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.

(y)           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 most recent Preliminary Prospectus which is not so described.

(z)            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.

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(aa)         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).

(bb)         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 deficiencies that could, in the aggregate, reasonably be expected to have a Material Adverse Effect.

(cc)         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, in the aggregate, reasonably be expected to have a Material Adverse Effect.

(dd)         Neither the Company nor any subsidiary is, and as of the applicable Delivery Date, will be (i) an “investment company” within the meaning of such term under the Investment Company Act of 1940, as amended (the “Investment Company Act”), and the Rules and Regulations, or (ii) a “business development company” as defined in Section 2(a)(48) of the Investment Company Act.

(ee)         Since the date of the most recent audited balance sheet of the Company and its consolidated subsidiaries included or incorporated by reference in the most recent Preliminary Prospectus, (i) the Company has not been advised of (A) any significant

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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 or (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.

(ff)           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, the Prospectus and any Issuer Free Writing Prospectus to which the Underwriter has consented in accordance with Section 1(g) or 6(a)(vi).

(gg)         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.

(hh)         The Stock has been approved for inclusion, subject to official notice of issuance, in the Nasdaq Global Market.

(ii)           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 most recent Preliminary Prospectus, except for any of the foregoing that could not, in the aggregate, 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, in the aggregate, reasonably be expected to have a Material Adverse Effect.

(jj)           Except as described in the most recent Preliminary 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 mark 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 most recent Preliminary 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.

(kk)         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,

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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, 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, 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.

(ll)           The Principal Subsidiary indirectly, and through one or more of its wholly-owned, direct subsidiaries, owns in excess of 80% of the value reflected in the financial statements of the Company 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 counsel for the Underwriter in connection with the offering of the Stock shall be deemed a representation and warranty by the Company, as to matters covered thereby, to the Underwriter.

2.     Representations, Warranties and Agreements of the Selling Stockholders.  Each Selling Stockholder, severally and not jointly, represents, warrants and agrees that

(a)           Neither the Selling Stockholder nor any person acting on behalf of the Selling Stockholder (other than, if applicable, the Company and the Underwriter) has used or referred to any “free writing prospectus” (as defined in Rule 405 of the Rules and Regulations), relating to the Stock;

(b)           The Selling Stockholder has, and immediately prior to any Delivery Date on which the Selling Stockholder is selling shares of Stock, the Selling Stockholder will have, good and valid title to the shares of Stock to be sold by the Selling Stockholder hereunder on such Delivery Date, free and clear of all liens, encumbrances, equities or claims.

(c)           The Stock to be sold by the Selling Stockholder hereunder is subject to the interest of the Underwriter and the other Selling Stockholders thereunder, and the arrangements made by the Selling Stockholder for such custody are to that extent irrevocable, and the obligations of the Selling Stockholder hereunder shall not be

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terminated by any act of the Selling Stockholder, by operation of law, by the death or incapacity of any individual Selling Stockholder or, in the case of a trust, by the death or incapacity of any executor or trustee or the termination of such trust, or the occurrence of any other event.

(d)           Upon payment for the Stock to be sold by such Selling Stockholder, delivery of such Stock, as directed by the Underwriter, to Cede & Co. (“Cede”) or such other nominee as may be designated by The Depository Trust Company (“DTC”), registration of such Stock in the name of Cede or such other nominee and the crediting of such Stock on the books of DTC to securities accounts of the Underwriter (assuming that neither DTC nor such Underwriter has notice of any adverse claim (within the meaning of Section 8-105 of the Delaware UCC (the “UCC”)) to such Stock), (i) DTC shall be a “protected purchaser” of such Stock within the meaning of Section 8-303 of the UCC, (ii) under Section 8-501 of the UCC, the Underwriter will acquire a valid security entitlement in respect of such Stock and (iii) no action based on any “adverse claim,” within the meaning of Section 8-102 of the UCC, to such Stock may be successfully asserted against the Underwriter with respect to such security entitlement.  For purposes of this representation, such Selling Stockholder may assume that when such payment, delivery and crediting occur, (A) such Stock will have been registered in the name of Cede or another nominee designated by DTC, in each case on the Company’s share registry in accordance with its certificate of incorporation, bylaws and applicable law, (B) DTC will be registered as a “clearing corporation” within the meaning of Section 8-102 of the UCC and (C) appropriate entries to the accounts of the Underwriter on the records of DTC will have been made pursuant to the UCC.

(e)           The Selling Stockholder has duly and irrevocably executed and delivered a power of attorney (the “Power of Attorney” and, together with all other similar agreements executed by the other Selling Stockholders, the “Powers of Attorney”) appointing Messrs. Schaeffer, Harrison and Beury as attorneys-in-fact, with full power of substitution, and with full authority (exercisable by any one or more of them) to execute and deliver this Agreement and to take such other action as may be necessary or desirable to carry out the provisions hereof on behalf of the Selling Stockholder.

(f)            The Selling Stockholder has full right, power and authority, corporate or otherwise, to enter into this Agreement and the Power of Attorney.

(g)           This Agreement has been duly and validly authorized, executed and delivered by or on behalf of the Selling Stockholder.

(h)           The Power of Attorney has been duly and validly authorized, executed and delivered by or on behalf of the Selling Stockholder and constitutes valid and legally binding obligations of the Selling Stockholder, enforceable against the Selling Stockholder in accordance with its terms, subject to (i) the effects of bankruptcy, insolvency, fraudulent conveyance, reorganization, moratorium and other similar laws relating to or affecting creditors’ rights generally, (ii) general equitable principles (whether considered in a proceeding in equity or at law) and (iii) an implied covenant of good faith and fair dealing

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(i)            The execution, delivery and performance of this Agreement and the Power of Attorney by the Selling Stockholder and the consummation by the Selling Stockholder of the transactions contemplated hereby and thereby do not and will not (i) conflict with or result in a breach or violation of any of the terms or provisions of, or constitute a default under, any indenture, mortgage, deed of trust, loan agreement, license or other agreement or instrument to which the Selling Stockholder is a party or by which the Selling Stockholder is bound or to which any of the property or assets of the Selling Stockholder is subject, (ii) result in any violation of the provisions of the charter, by-laws, deed of trust (or similar organizational documents) of the Selling Stockholder, 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 Selling Stockholder or the property or assets of the Selling Stockholder, except in the case of clauses (i) or (iii) for such conflicts, breaches, violations or defaults as would not, individually or in the aggregate, reasonably be expected to have a material adverse effect on the ability of such Selling Stockholder to consummate the transactions contemplated by this Agreement.

(j)            No consent, approval, authorization or order of, or filing or registration with, any court or governmental agency or body having jurisdiction over the Selling Stockholder or the property or assets of the Selling Stockholder is required for the execution, delivery and performance of this Agreement or the Power of Attorney by the Selling Stockholder and the consummation by the Selling Stockholder of the transactions contemplated hereby and thereby, 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 or foreign securities laws in connection with the purchase and sale of the Stock by the Underwriter.

(k)           The Selling Stockholder is familiar with the Registration Statement, the Prospectus and the Pricing Disclosure Package (as amended or supplemented) and has no knowledge of any material fact, condition or information not disclosed (i) in the Registration Statement, as of the Effective Date, (ii) in the Prospectus, as of its date and on the applicable Delivery Date, or (iii) in the Pricing Disclosure Package, as of the Applicable Time, that, in each case, could reasonably be expected to have a Material Adverse Effect.  The Selling Stockholder is not prompted to sell shares of Common Stock by any information concerning the Company that is not set forth in the Registration Statement, the Pricing Disclosure Package and the Prospectus.

(l)            The Selling Stockholder has not taken and will not take, directly or indirectly, any action that is 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.

(m)          To the knowledge of the Selling Stockholder, the sale of the Stock by the Selling Stockholder does not violate any of the Company’s internal policies regarding the sale of stock by its affiliates.

Any certificate signed by or on behalf of any Selling Stockholder and delivered to counsel for the Underwriter in connection with the offering of the Stock shall be deemed a representation and warranty by such Selling Stockholder, as to matters covered thereby, to the Underwriter.

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3.     Purchase of the Stock by the Underwriter.  On the basis of the representations and warranties contained in, and subject to the terms and conditions of, this Agreement, each Selling Stockholder agrees to sell the number of shares of Stock set forth opposite its name in Schedule 2 hereto, severally and not jointly, to the Underwriter, and the Underwriter agrees to purchase the Stock.

The price of the Stock purchased by the Underwriter shall be $14.64 per share.

The Selling Stockholders shall not be obligated to deliver any of the 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.

4.     Offering of Stock by the Underwriter.   The Underwriter proposes to offer the Stock for sale upon the terms and conditions set forth in the Prospectus.

5.     Delivery of and Payment for the Stock.  Delivery of and payment for the Stock shall be made at 10:00 A.M., New York City time, on November 14, 2006 at the offices of Latham & Watkins LLP, 555 Eleventh Street, NW, Suite 1000, Washington, DC or at such other date or place as shall be determined by agreement between the Underwriter and the Company.  This date and time are sometimes referred to as the “Delivery Date.”  Delivery of the Stock shall be made to the Underwriter against payment by the Underwriter of the respective aggregate purchase prices of the Stock being sold by the Selling Stockholders to or upon the order of the Selling Stockholders by wire transfer in immediately available funds to the accounts specified by the Selling Stockholders.  Time shall be of the essence, and delivery at the time specified pursuant to this Agreement is a further condition of the obligation of the Underwriter hereunder.  Delivery of the Stock shall be made through the facilities of DTC unless the Underwriter shall otherwise instruct.

6.     Further Agreements of the Company and the Underwriter.

(a) The Company agrees:

(i)            To prepare the Prospectus in a form approved by the Underwriter 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 Delivery Date except as permitted herein; to advise the Underwriter, 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 Underwriter with copies thereof; to file promptly all reports and any definitive proxy or information statements required to be filed by the Company with the Commission pursuant to Section 13(a), 13(c), 14 or 15(d) of the Exchange Act subsequent to the date of the Prospectus and for so long as the delivery of a prospectus is

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required in connection with the offering or sale of the Stock; to advise the Underwriter, 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, the Prospectus or any Issuer Free Writing 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, the Prospectus or any Issuer Free Writing 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, the Prospectus or any Issuer Free Writing Prospectus or suspending any such qualification, to use promptly its best efforts to obtain its withdrawal;

(ii)           To furnish promptly to counsel for the Underwriter 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;

(iii)          To deliver promptly to the Underwriter such number of the following documents as the Underwriter shall reasonably request:  (A) 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), (B) each Preliminary Prospectus, the Prospectus and any amended or supplemented Prospectus, (C) each Issuer Free Writing Prospectus, and (D) any document incorporated by reference in any Preliminary Prospectus or the Prospectus; and, if the delivery of a prospectus is required at any time after the date hereof 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 or to file under the Exchange Act any document incorporated by reference in the Prospectus in order to comply with the Securities Act or the Exchange Act, to notify the Underwriter and, upon its request, to file such document and to prepare and furnish without charge to the Underwriter and to any dealer in securities as many copies as the Underwriter may from time to time reasonably request of an amended or supplemented Prospectus that will correct such statement or omission or effect such compliance;

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

(v)           Prior to filing with the Commission any amendment to the Registration Statement or supplement to the Prospectus, any Prospectus pursuant to Rule 424(b) of the Rules and Regulations, any document incorporated by reference in the Prospectus or any amendment to any document incorporated by reference in the Prospectus, to furnish a copy thereof to counsel for the Underwriter and obtain the consent of the Underwriter to the filing;

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(vi)          Not to make any offer relating to the Stock that would constitute an Issuer Free Writing Prospectus without the prior written consent of the Underwriter to the filing;

(vii)         To retain in accordance with the Rules and Regulations all Issuer Free Writing Prospectuses not required to be filed pursuant to the Rules and Regulations; and if at any time after the date hereof any events shall have occurred as a result of which any Issuer Free Writing Prospectus, as then amended or supplemented, would conflict with the information in the Registration Statement, the most recent Preliminary Prospectus or the Prospectus or 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, not misleading, or, if for any other reason it shall be necessary to amend or supplement any Issuer Free Writing Prospectus, to notify the Underwriter and, upon their request, to file such document and to prepare and furnish without charge to the Underwriter as many copies as the Underwriter may from time to time reasonably request of an amended or supplemented Issuer Free Writing Prospectus that will correct such conflict, statement or omission or effect such compliance;

(viii)        As soon as practicable after the Effective Date, and in any event not later than 16 months after the date hereof, to make generally available to the Company’s security holders and to deliver to the Underwriter 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);

(ix)           Promptly from time to time to take such action as the Underwriter may reasonably request to qualify the Stock for offering and sale under the securities laws of such jurisdictions as the Underwriter 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;

(x)            For a period commencing on the date hereof through and including the 30th day after the date of the Prospectus (the “Company 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

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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 Underwriter (the lock-up applicable to the Company as described in this paragraph being the “Company Lock-Up”), and to cause each officer, director and stockholder of the Company set forth on Schedule 2 hereto to furnish to the Underwriter, 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; and

Notwithstanding the foregoing paragraph, if (1) during the last 17 days of the Company 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 Company Lock-Up Period, the Company announces that it will release earnings results during the 16-day period beginning on the last day of the Company 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 Underwriter waives such extension in writing; provided, however, that this sentence shall not apply if the Underwriter publishes or distributes any research regarding the earnings results, material news or material event, and such research is compliant under Rule 139 of the Securities Act of 1933, as amended, and the Company’s securities are actively traded as defined in Rule 101(c)(1) of Regulation M under the Securities Exchange Act of 1934, as amended.

(b)           The Underwriter agrees that it shall not include any “issuer information” (as defined in Rule 433) in any “free writing prospectus” (as defined in Rule 405 of the Rules and Regulations) used or referred to by the Underwriter without the prior consent of the Company (any such issuer information the Company has given its consent to, “Permitted Issuer Information”); provided that (i) no such consent shall be required with respect to any such issuer information contained in any document filed by the Company with the Commission prior to the use of such free writing prospectus and (ii) “issuer information,” as used in this Section 6(b), shall not be deemed to include information prepared by or on behalf of the Underwriter on the basis of or derived from issuer information.

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7.     Further Agreements of the Selling Stockholders.  Each Selling Stockholder severally and not jointly hereby agrees:

(a)           That on or prior to the date hereof it shall have entered into a Lock-Up Agreement in the form of Exhibit A;

(b)           That the Stock to be sold by the Selling Stockholder hereunder is subject to the interest of the Underwriter and the other Selling Stockholders thereunder, that the arrangements made by the Selling Stockholder for such custody are to that extent irrevocable, and that the obligations of the Selling Stockholder hereunder shall not be terminated by any act of the Selling Stockholder, by operation of law, by the death or incapacity of any individual Selling Stockholder or, in the case of a trust, by the death or incapacity of any executor or trustee or the termination of such trust, or the occurrence of any other event;

(c)           Neither the Selling Stockholder nor any person acting on behalf of the Selling Stockholder (other than, if applicable, the Company and the Underwriter) shall use or refer to any “free writing prospectus” (as defined in Rule 405 of the Rules and Regulations), relating to the Stock; and

(d)           To deliver to the Underwriter prior to the Initial Delivery Date a properly completed and executed United States Treasury Department Form W-8 (if the Selling Stockholder is a non-United States person) or Form W-9 (if the Selling Stockholder is a United States person).

8.     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, the Issuer Free Writing Prospectus and any amendment or supplement to the Prospectus or the Issuer Free Writing 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, the Issuer Free Writing Prospectus and any amendment or supplement to the Prospectus or the Issuer Free Writing Prospectus and any document incorporated by reference therein, all as provided in this Agreement; (d) the production and distribution of this Agreement, any supplemental agreement among Underwriter and any other related documents in connection with the offering, purchase, sale and delivery of the Stock; (e) the delivery and distribution of the Powers of Attorney and the fees and expenses, if any, of the custodian and any attorney-in-fact; (f) 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 Underwriter); (g) the inclusion of the Stock on the Nasdaq Global Market and/or any other exchange; (h) the qualification of the Stock under the securities laws of the several jurisdictions as provided in Section 6(a)(xi) and the preparation, printing and distribution of a Blue Sky Memorandum (including related fees and expenses of counsel to the Underwriter not to exceed, in the aggregate, $2,500); (i) its expenses incurred in connection with any “road show” undertaken in connection with the marketing of the Stock, including food, lodging, travel and other expenses for Company

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representatives and officers; and (j) all other costs and expenses incident to the performance of the obligations of the Company and the Selling Stockholders under this Agreement; provided that, except as provided in this Section 8 and in Section 13, the Underwriter shall pay its own costs and expenses, including but not limited to the costs and expenses of its counsel, its costs and expenses of the road show including food, lodging, travel and other expenses for its representatives and any aircraft chartered in connection therewith, any transfer taxes on the Stock which it may sell and the expenses of advertising any offering of the Stock made by the Underwriter and the Selling Stockholders shall pay any transfer taxes payable in connection with their respective sales of Stock to the Underwriter.  Nothing in this Section 8 shall affect any agreement that some or all of the Selling Stockholders may have among themselves or with the Company as to the sharing of expenses among the Selling Stockholders and the Company.

9.     Conditions of Underwriter’s Obligations.   The obligations of the Underwriter hereunder are subject to the accuracy, when made and on the Delivery Date, of the representations and warranties of the Company, the Principal Subsidiary and the Selling Stockholders contained herein, to the performance by the Company and the Selling Stockholders of their respective 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 6(a)(i); the Company shall have complied with all filing requirements applicable to any Issuer Free Writing Prospectus used or referred to after the date hereof; no stop order suspending the effectiveness of the Registration Statement or preventing or suspending the use of the Prospectus or any Issuer Free Writing 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, the Prospectus or the Pricing Disclosure Package, or any amendment or supplement thereto, contains an untrue statement of a fact which, in the opinion of Mayer, Brown, Rowe & Maw LLP, counsel for the Underwriter, 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 Powers of Attorney, the Stock, the Registration Statement, the Prospectus and any Issuer Free Writing 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 Underwriter, and the Company and the Selling Stockholders shall have furnished to such counsel all documents and information that they may reasonably request to enable them to pass upon such matters.

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(d)           Latham & Watkins LLP shall have furnished to the Underwriter its written opinions, as counsel to the Company, addressed to the Underwriter and dated such Delivery Date, in form and substance reasonably satisfactory to the Underwriter, substantially in the forms attached hereto as Exhibit B-1 and Exhibit B-2 and the statement of Latham & Watkins as to certain other matters as set forth in Exhibit B-3.

(e)           Robert Beury, General Counsel of the Company, shall have furnished to the Underwriter his written opinion addressed to the Underwriter and dated such Delivery Date, in form and substance reasonably satisfactory to the Underwriter, substantially in the form attached hereto as Exhibit C.

(f)            Elvinger Hoss et Prussen shall have furnished to the Underwriter its written opinion, as Luxembourg counsel to the Company, addressed to the Underwriter and dated such Delivery Date, in form and substance reasonably satisfactory to the Underwriter, substantially in the form attached hereto as Exhibit D.

(g)           The Underwriter shall have received the written opinions of counsel to each Selling Stockholder addressed to the Underwriter and dated such Delivery Date, in form and substance reasonably satisfactory to the Underwriter, substantially in the form attached hereto as Exhibit E.

(h)           The Underwriter shall have received from Mayer, Brown, Rowe & Maw LLP, counsel for the Underwriter, such opinion or opinions, dated such Delivery Date, with respect to the issuance and sale of the Stock, the Registration Statement, the Prospectus, the Pricing Disclosure Package and other related matters as the Underwriter 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.

(i)            On the date of execution of this Agreement, the Underwriter shall have received from Ernst & Young LLP a letter, in form and substance satisfactory to the Underwriter, addressed to the Underwriter 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.

(j)            With respect to the letter of Ernst & Young LLP referred to in the preceding paragraph and delivered to the Underwriter concurrently with the execution of this Agreement (the “initial letter”), the Company shall have furnished to the Underwriter a letter (the “bring-down letter”) of such accountants, addressed to the Underwriter and dated such Delivery Date (i) confirming that they are independent

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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.

(k)           The Company shall have furnished to the Underwriter 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; and

(iii)          They have carefully examined the Registration Statement, the Prospectus and the Pricing Disclosure Package and, in their opinion, (A)(1) the Registration Statement, as of the Effective Date, (2) the Prospectus, as of its date and as of such Delivery Date, and (3) the Pricing Disclosure Package, as of the Applicable Time, 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 (except in the case of the Registration Statement, in the light of the circumstances under which they were made) not misleading, and (B) since the Effective Date, no event has occurred that should have been set forth in an amendment to the Registration Statement or a supplement to the Prospectus or any Issuer Free Writing Prospectus that has not been so set forth.

(l)            Each Selling Stockholder (or one or more attorneys-in-fact on behalf of the Selling Stockholders) shall have furnished to the Underwriter on such Delivery Date a certificate, dated such Delivery Date, signed by, or on behalf of, the Selling Stockholder (or one or more attorneys-in-fact) stating that the representations, warranties and agreements of the Selling Stockholder contained herein are true and correct on and as of such Delivery Date, or true and correct in all material respects where such representations and warranties are not qualified by materiality, and that the Selling Stockholder has complied in all material respects with all its agreements contained herein and has satisfied all the conditions on its part to be performed or satisfied hereunder at or prior to such Delivery Date.

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(m)          (i) Neither the Company nor any of its subsidiaries shall have sustained, since the date of the latest audited financial statements included or incorporated by reference in the most recent Preliminary 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 Underwriter, 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.

(n)           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 Underwriter, 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.

(o)                   The Nasdaq Stock Market LLC shall have approved the Stock for inclusion in the Nasdaq Global Market, subject only to official notice of issuance.

(p)                   The Lock-Up Agreements between the Underwriter and the officers, directors and stockholders of the Company set forth on Schedule 2, delivered to the Underwriter 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 Underwriter.

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10.   Indemnification and Contribution.

(a)           The Company and the Principal Subsidiary shall jointly and severally indemnify and hold harmless the Underwriter, its directors, officers and employees and each person, if any, who controls the 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 the 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 in (A) any Preliminary Prospectus, the Registration Statement, the Prospectus or in any amendment or supplement thereto, (B) any Issuer Free Writing Prospectus or in any amendment or supplement thereto, (C) any Permitted Issuer Information used or referred to in any “free writing prospectus” (as defined in Rule 405of the Rules and Regulations) used or referred to by any Underwriter, or (D) any “road show” (as defined in Rule 433 of the Rules and Regulations) not constituting an Issuer Free Writing Prospectus (a “Non-Prospectus Road Show”), (ii) the omission or alleged omission to state in any Preliminary Prospectus, the Registration Statement, the Prospectus, any Issuer Free Writing Prospectus or in any amendment or supplement thereto or in any Permitted Issuer Information or any Non-Prospectus Road Show, 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, the Prospectus, any Issuer Free Writing Prospectus or in any such amendment or supplement thereto or in any Permitted Issuer Information or any Non-Prospectus Road Show, in reliance upon and in conformity with written information concerning such Underwriter furnished to the Company by or on behalf of any Underwriter specifically for inclusion therein, which information consists solely of the information specified in Section 10(f).  The foregoing indemnity agreement is in addition to any liability which the Company may otherwise

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have to the Underwriter or to any director, officer, employee or controlling person of the Underwriter.

(b)           The Selling Stockholders, severally, and not jointly in proportion to the number of shares of Stock to be sold by each of them hereunder, shall indemnify and hold harmless the Underwriter, its directors, officers and employees, and each person, if any, who controls the 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 the 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 in any Preliminary Prospectus, the Registration Statement, the Prospectus, any Issuer Free Writing Prospectus or in any amendment or supplement thereto or in any Permitted Issuer Information, any Non-Prospectus Road Show or any “free writing prospectus” (as defined in Rule 405 of the Rules and Regulations) prepared by or on behalf of the Selling Stockholder or used or referred to by the Selling Stockholder in connection with the offering of the Stock in violation of Section 7(c) (a “Selling Stockholder Free Writing Prospectus”), (ii) the omission or alleged omission to state in any Preliminary Prospectus, Registration Statement, the Prospectus, any Issuer Free Writing Prospectus or in any amendment or supplement thereto or in any Permitted Issuer Information, any Non-Prospectus Road Show or any Selling Stockholder Free Writing Prospectus, any material fact required to be stated therein or necessary to make the statements therein not misleading, and shall reimburse the Underwriter, its directors, officers and employees and each such controlling person promptly upon demand for any legal or other expenses reasonably incurred by the Underwriter, its directors, officers and employees or controlling persons in connection with investigating or defending or preparing to defend against any such loss, claim, damage, liability or action as such expenses are incurred or (iii) any breach of any representation or warranty of the Selling Stockholders in this Agreement or any certificate or other agreement delivered pursuant hereto or  contemplated hereby; provided, however, that the Selling Stockholders 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, the Prospectus, any Issuer Free Writing Prospectus or in any such amendment or supplement thereto or in any Permitted Issuer Information or any Non-Prospectus Road Show or any Selling Stockholder Free Writing Prospectus, in reliance upon and in conformity with written information concerning the Underwriter furnished to the Company by or on behalf of any Underwriter specifically for inclusion therein, which information consists solely of the information specified in Section 10(f).  The liability of a Selling Stockholder under the indemnity agreement contained in this paragraph shall be limited to an amount equal to the total net proceeds from the offering of the shares of the Stock purchased under the Agreement received by the Selling Stockholder, determined by multiplying the proceeds to the Selling Stockholders per share as set forth in the table on the cover page of the Prospectus by the number of shares of Stock sold by such Selling Stockholder.  The foregoing indemnity agreement is in addition to any liability that the Selling

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Stockholders may otherwise have to the Underwriter or any officer, employee or controlling person of the Underwriter.

(c)           The Underwriter shall indemnify and hold harmless the Company, each Selling Stockholder, their respective directors, officers and employees, and each person, if any, who controls the Company or such Selling Stockholder 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, such Selling Stockholder 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, the Prospectus any Issuer Free Writing Prospectus or in any amendment or supplement thereto or in any Non-Prospectus Road Show, or (ii) the omission or alleged omission to state in any Preliminary Prospectus, the Registration Statement, the Prospectus, the Issuer Free Writing Prospectus or in any amendment or supplement thereto or in any Non-Prospectus Road Show, 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 the Underwriter furnished to the Company by or on behalf of that Underwriter specifically for inclusion therein, which information is limited to the information set forth in Section 10(f) and shall reimburse the Company, such Selling Stockholder and any such director, officer or controlling person for any legal or other expenses reasonably incurred by the Company, such Selling Stockholder 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 the Underwriter may otherwise have to the Company, such Selling Stockholder or any such director, officer, employee or controlling person.

(d)           Promptly after receipt by an indemnified party under this Section 10 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 10, 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 10 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 10.  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 10 for any legal or other expenses subsequently

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incurred by the indemnified party in connection with the defense thereof other than reasonable costs of investigation; provided, however, that the Underwriter shall have the right to employ counsel to represent the Underwriter and its 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 Underwriter against the Company under this Section 10 if (i) the Company, the Selling Stockholders and the Underwriter shall have so mutually agreed; (ii) the Company or the Selling Stockholders have failed within a reasonable time to retain counsel reasonably satisfactory to the Underwriter; (iii) the Underwriter and its 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 the Selling Stockholders; or (iv) the named parties in any such proceeding (including any impleaded parties) include both the Underwriter or its respective directors, officers, employees or controlling persons, on the one hand, and the Company or the Selling Stockholders, on the other hand, and represen­tation of those 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 for 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.

(e)           If the indemnification provided for in this Section 10 shall for any reason be unavailable to or insufficient to hold harmless an indemnified party under Section 10(a), 10(b) or 10(c) 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, the Principal Subsidiary and the Selling Stockholders, on the one hand, and the Underwriter, 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, the Principal Subsidiary and the Selling Stockholders, on the one hand, and the Underwriter, 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

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benefits received by the Company, the Principal Subsidiary and the Selling Stockholders, on the one hand, and the Underwriter, 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 and the Selling Stockholders, 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 Underwriter 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, the Selling Stockholders or the Underwriter, 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, the Selling Stockholders and the Underwriter agree that it would not be just and equitable if contributions pursuant to this Section 10(e) were to be determined by pro rata allocation 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 10(e) shall be deemed to include, for purposes of this Section 10(e), 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 10(e), the Underwriter shall not 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 the 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

(f)            The Underwriter confirm sand the Company and the Selling Stockholders acknowledge and agree that the statements with respect to the delivery of the shares of the Stock by the Underwriter set forth on the cover page of the Prospectus, and the concession and reallowance figures, the paragraph relating to stabilization by the Underwriter appearing under the caption “Underwriting”, and in the first paragraph under the heading “Electronic Distribution” appearing under the caption “Underwriting” in the Prospectus, are correct and constitute the only information concerning the Underwriter furnished in writing to the Company by or on behalf of the Underwriter specifically for inclusion in any Preliminary Prospectus, the Registration Statement, the Prospectus, any Issuer Free Writing Prospectus or any amendment or supplement thereto or in any Non-Prospectus Road Show.

11.   Termination.   The obligations of the Underwriter hereunder may be terminated by the Underwriter by notice given to and received by the Company and the Selling

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Stockholders prior to delivery of and payment for the Firm Stock if, prior to that time, any of the events described in Sections 9(m) or 9(n) shall have occurred (or not occurred, as the case may be) or if the Underwriter shall decline to purchase the Stock for any reason permitted under this Agreement.

12.   Reimbursement of Underwriter’s Expenses.   If any Selling Stockholder shall fail to tender the Stock for delivery to the Underwriter by reason of any failure, refusal or inability on the part of the Company or the Selling Stockholder or its representatives to perform any agreement on their part to be performed, or because any other condition of the Underwriter’s obligations hereunder required to be fulfilled by the Company or a Selling Stockholder is not fulfilled, the Company will reimburse the Underwriter for all reasonable out-of-pocket expenses (including fees and disbursements of counsel) incurred by the Underwriter 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 Underwriter.

13.   Research Independence.  In addition, the Company acknowledges that the Underwriter’s 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 the Underwriter’s 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 and each Selling Stockholder hereby waive and release, to the fullest extent permitted by law, any claims that the Company or such Selling Stockholder may have against the Underwriter 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 or the Selling Stockholders by such Underwriter’s investment banking divisions.  The Company and the Selling Stockholders acknowledge that the Underwriter 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.

14.   No Fiduciary Duty.  The Company and the Selling Stockholders acknowledge and agree that in connection with this offering, the sale of the Stock or any other services the Underwriter may be deemed to be providing hereunder, notwithstanding any preexisting relationship, advisory or otherwise, between the parties or any oral representations or assurances previously or subsequently made by the Underwriter: (i) no fiduciary or agency relationship between the Company, the Selling Stockholders and any other person, on the one hand, and the Underwriter, on the other, exists; (ii) the Underwriter is not acting as an advisor, an expert or otherwise, to either the Company or the Selling Stockholders, including, without limitation, with respect to the determination of the public offering price of the Stock, and such relationship between the Company and the Selling Stockholders, on the one hand, and the Underwriter, on the other, is entirely and solely commercial, based on arms-length negotiations; any duties and obligations that the Underwriter may have to the Company or Selling Stockholders shall be limited to those duties and obligations specifically stated herein; and (iv) the Underwriter and its affiliates may have interests that differ from those of the Company and the Selling Stockholders.  The Company and each Selling Stockholders hereby

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waive any claims that the Company or such Selling Stockholder may have against the Underwriter with respect to any breach of fiduciary duty in connection with this offering.

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

(a)           Notices to the Underwriter shall be given to the Underwriter c/o RBC Capital Markets Corporation, One Liberty Plaza 6th floor, New York, New York 10006; Attention: Joe Morea, Syndicate Director (Fax: (212) 428-6260).

(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: Robert N. Beury, Jr. (Fax: 202 ###-###-####); and

(c)           if to the Selling Stockholders, shall be delivered or sent by mail, telex or facsimile transmission to such Selling Stockholder at the address set forth on Schedule 2 hereto.

16.   Persons Entitled to Benefit of Agreement.   This Agreement shall inure to the benefit of and be binding upon the Underwriter, the Company, the Principal Subsidiary, the Selling Stockholders and their respective personal representatives and 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,  the Principal Subsidiary and the Selling Stockholders contained in this Agreement shall also be deemed to be for the benefit of the directors, officers and employees of the Underwriter and each person or persons, if any, who control the Underwriter within the meaning of Section 15 of the Securities Act and (B) the indemnity agreement of the Underwriter contained in Section 10(c) 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, any person controlling the Company within the meaning of Section 15 of the Securities Act and any directors of a Selling Stockholder and any person controlling such Selling Stockholder 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 17, any legal or equitable right, remedy or claim under or in respect of this Agreement or any provision contained herein.

17.   Survival.   The respective indemnities, representations, warranties and agreements of the Company, the Principal Subsidiary, the Selling Stockholders and the Underwriter 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.

18.   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.

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

20.   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.

21.   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.

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

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SCHEDULE 1

PERSONS DELIVERING LOCK-UP AGREEMENTS

The individuals and entities listed in Schedule 2, except for Natio Vie Developpment 3, FCPR.

SCHEDULE 2

SELLING STOCKHOLDERS

Addresses:

(1)                                  C/O CIBC Financial Center, Third Floor, 11, Dr. Roy’s Drive, P.O. Box 694 GT, Grand Cayman, Cayman Islands, British West Indies

(2)                                  C/O BNP Private Equity SA, 32 Boulevard Haussmann, Paris, France 75009

(3)                                  1810 Gateway Dr., Suite 260, San Mateo, CA  94404

(4)                                  203 SE Park Plaza Drive, Suite 270, Vancouver, WA 98684

(5)                                  C/O JVP Consulting Inc., 41 Madison Ave 25th Floor, New York, NY 10010

(6)                                  One Gorham Island, Westport, CT 06880

(7)                                  435 Tasso Street, Suite 120, Palo Alto, CA 94301

FORM OF LOCK-UP LETTER AGREEMENT

RBC CAPITAL MARKETS CORPORATION
One Liberty Plaza, 6th floor
New York, New York 10006

Ladies and Gentlemen:

The undersigned understands that you (the “Underwriter”) propose to enter into an Underwriting Agreement (the “Underwriting Agreement”) providing for the purchase by the Underwriter of shares (the “Shares”) of Common Stock, par value $0.001 per share (the “Common Stock”), of Cogent Communications Group, Inc., a Delaware corporation (the “Company”), and that the Underwriter proposes to reoffer the Shares to the public (the “Offering”).

In consideration of the execution of the Underwriting Agreement by the Underwriter, and for other good and valuable consideration, the undersigned hereby irrevocably agrees that, without the prior written consent of the Underwriter the undersigned will not, 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 (including, without limitation, shares of Common Stock that may be deemed to be beneficially owned by the undersigned in accordance with the rules and regulations of the Securities and Exchange Commission and shares of Common Stock that may be issued upon exercise of any option or warrant) or securities convertible into or exchangeable for Common Stock (other than the Shares in the Offering), (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 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) make any demand for or exercise any right or file or cause to be filed a registration statement, including any amendments, with respect to the registration of 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 Underwriter for a period commencing on the date hereof and ending 30 days thereafter with respect to such shares or securities (the “Base Shares”) so indicated (the “Lock-Up Period”).  The foregoing sentence shall not apply to bona fide gifts or other dispositions of Common Stock, in each case that are made exclusively between and among the undersigned or members of the undersigned’s family, or affiliates of the undersigned, including its partners (if a partnership) or members (if a limited liability company); provided that it shall be a condition to any such transfer that (i) the transferee/donee agrees to be bound by the terms of this Lock-Up Letter Agreement (including, without limitation, the restrictions set forth in the preceding sentence) to the same extent as if the transferee/donee were a party hereto, (ii) no filing by any party (donor, donee, transferor or transferee) under the Securities Exchange Act of

1934, as amended (the “Exchange Act”), shall be required or shall be voluntarily made in connection with such transfer or distribution (other than a filing on a Form 5, Schedule 13D or Schedule 13G (or 13D-A or 13G-A) made after the expiration of the Lock-Up Period), (iii) each party (donor, donee, transferor or transferee) shall not be required by law (including without limitation the disclosure requirements of the Securities Act of 1933, as amended, and the Exchange Act) to make, and shall agree to not voluntarily make, any public announcement of the transfer or disposition, (iv) any such transfer shall not involve a disposition for value, and (v) the undersigned notifies RBC Capital Markets Corporation at least two business days prior to the proposed transfer or disposition.

Notwithstanding the foregoing paragraph, if (1) during the last 17 days of either 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 Underwriter waives such extension in writing; provided, however that in no event shall any such extension of the Lock-Up Period last beyond the 34th day following the originally contemplated end of such period; and provided, further, that this sentence shall not apply if the Underwriter publish or distribute any research regarding the earnings results, material news or material event, and such research is compliant under Rule 139 of the Securities Act of 1933, as amended, and the Company’s securities are actively traded as defined in Rule 101(c)(1) of Regulation M under the Securities Exchange Act of 1934, as amended.  The undersigned hereby further agrees that, prior to engaging in any transaction or taking any other action that is subject to the terms of this Lock-Up Letter Agreement during the period from the date of this Lock-Up Letter Agreement to and including the 34th day following the expiration of the Lock-Up Period, it will give notice thereof to the Company and will not consummate such transaction or take any such action unless it has received written confirmation from the Company that the Lock-Up Period (as such may have been extended pursuant to this paragraph) has expired.

In furtherance of the foregoing, the Company and its transfer agent are hereby authorized to decline to make any transfer of securities if such transfer would constitute a violation or breach of this Lock-Up Letter Agreement.

The undersigned hereby represents and warrants that the undersigned has full power and authority to enter into this Lock-Up Letter Agreement and that, upon request, the undersigned will execute any additional documents necessary in connection with the enforcement hereof.  Any obligations of the undersigned shall be binding upon the heirs, personal representatives, successors and assigns of the undersigned.

The undersigned hereby represents and warrants that the undersigned has full power and authority to enter into this Lock-Up Letter Agreement and that, upon request, the undersigned will execute any additional documents necessary in connection with the enforcement hereof.  Any obligations of the undersigned shall be binding upon the heirs, personal representatives, successors and assigns of the undersigned.

EXHIBIT E

FORM OF OPINION OF COUNSEL TO SELLING STOCKHOLDERS

1.             The Selling Stockholder has all requisite [corporate/limited partnership] power and authority to enter into the Underwriting Agreement, the Power of Attorney and the Lock-Up Letter Agreement to which it is a party.  The execution, delivery and performance of the Underwriting Agreement, each of the Power of Attorneys and each of the Lock-Up Letter Agreements by each Selling Stockholder and the consummation by such Selling Stockholder of the transactions contemplated in the Underwriting Agreement, the Power of Attorney and the Lock-Up Letter Agreement to which it is a party will not conflict with or result in a breach or violation of any of the terms or provisions of the [law under which entity organized], or any federal or State of New York statute known to us by which such Selling Stockholder is bound or to which any of the property or assets of such Selling Stockholder is subject, nor do such actions result in any violation of any [organizational documents of Selling Stockholder] or any statute or any order, rule or regulation known to us of any federal, State of New York or [state of organization] court or governmental agency or body having jurisdiction over such Selling Stockholder or the property or assets of such Selling Stockholder or constitute a default under any indenture, mortgage, deed of trust, loan agreement or instrument known to us (such knowledge based solely on a certificate from each such Selling Stockholder) to which the Selling Stockholders are a party.  Except for the registration of the Offering and the sale of the Stock under the Securities Act and such consents, approvals, authorizations, filings, reports, registrations or qualifications as may be required under the Exchange Act and applicable state securities laws (as to which we do not opine) in connection with the purchase and distribution of the Stock by the Underwriter, no consent, approval, authorization or order of, or filing or registration with, any such federal, State of New York or [state of organization] court or governmental agency or body is required for the execution, delivery and performance of the Underwriting Agreement, the Power of Attorneys and the Lock-Up Letter Agreements by each such Selling Stockholder which is a party thereto and the consummation by such Selling Stockholder of the transactions contemplated thereby.

2.             The Underwriting Agreement has been duly authorized, executed and delivered by or on behalf of each Selling Stockholder.

3.             Each Power of Attorney and the Lock-Up Letter Agreement has been duly authorized, executed and delivered by each Selling Stockholder which is a party thereto and constitutes the legal, valid and binding agreement of each such Selling Stockholder enforceable against such Selling Stockholder in accordance with its terms, except where (i) the enforceability thereof may be limited by bankruptcy, insolvency, reorganization, fraudulent conveyance, moratorium or other similar laws now or hereafter in effect relating to rights of creditors and other obligees generally, (ii) the remedy of specific performance and other forms of equitable relief may be subject to certain equitable defenses and principles and to the discretion of the court before which the proceedings

may be brought and (iii) rights to indemnity, contribution, reimbursement and the like may be limited by applicable law and public policy.

4.             Assuming that (a) DTC is a “clearing corporation” as defined in Section 8-102(a)(5) of the Uniform Commercial Code as in effect on the date hereof in the State of New York (the “UCC”), and (b) the Underwriter acquires its interest in the Stock it has purchased without notice of any adverse claim (within the meaning of Section 8-105 of the UCC), the Underwriter that has purchased Stock from the Selling Stockholders delivered on the date hereof to DTC, made payment therefore pursuant to the Underwriting Agreement and has had such Stock credited to a securities account of such Underwriter maintained with DTC will have acquired a securities entitlement (within the meaning of Section 8-102(a)(17) of the UCC) to such Stock, and no action based on an adverse claim may be successfully asserted against the Underwriter with respect to such security entitlement.

In rendering such opinion, such counsel may (i) state that its opinion is limited to matters governed by the federal laws of the United States of America, the laws of [insert name of jurisdiction in which such counsel practices] and [insert description of law (e.g., corporate, partnership, trust, etc.) of the jurisdiction in which the selling stockholders are organized] and that such counsel is not admitted in [insert jurisdiction in which the selling stockholder is organized].

Such counsel shall also have furnished to the Representatives a written statement, addressed to the Underwriter and dated such Delivery Date, in form and substance satisfactory to the Representatives, to the effect that such counsel has acted as counsel to the Selling Stockholder in connection with the preparation of the Registration Statement and although such counsel has not independently verified and is not passing upon and assumes no responsibility for the accuracy, completeness or fairness of the statements contained in the Registration Statement, the Prospectus, the most recent Preliminary Prospectus and the Issuer Free Writing Prospectuses set forth on Annex A to such opinion, based on the foregoing and solely with respect to information regarding the Selling Stockholder (relying as to factual matters upon the statements of officers and other representatives of the Selling Stockholder and others), no facts have come to such counsel’s attention that caused it to believe that the Registration Statement, as of the Effective Date, the Prospectus, as of its date and as of the date of such opinion, the most recent Preliminary Prospectus, as of the Applicable Time, and the Issuer Free Writing Prospectuses set forth on Annex A to such opinion, as of the Applicable Time, contained or contains an untrue statement of a material fact or omitted or omits to state a material fact required to be stated therein or necessary to make the statements therein, in light of the circumstances under which they were made, not misleading (it being understood that such counsel need express no view with respect to the financial statements and related notes thereto and the other financial and statistical information included in, incorporated by reference in, or excluded from the Registration Statement, the Prospectus, the most recent Preliminary Prospectus and the Issuer Free Writing Prospectuses set forth on Annex A to such opinion).