9,000,000 SHARES

                            MARKETAXESS HOLDINGS INC.

                                  COMMON STOCK

                             UNDERWRITING AGREEMENT

                                                            [        ], 2004


Credit Suisse First Boston LLC
J.P. Morgan Securities Inc.,
  As Representatives of the several Underwriters

c/o Credit Suisse First Boston LLC
    Eleven Madison Avenue
    New York, New York  10010-3629

    J.P. Morgan Securities Inc.
    277 Park Avenue
    New York, New York  10172


Ladies and Gentlemen:

      1. Introductory. MarketAxess Holdings Inc., a Delaware corporation (the
"COMPANY"), proposes to issue and sell 3,000,000 shares of its Common Stock, par
value $0.003 per share (the "SECURITIES"), and the stockholders listed in
Schedule I hereto (the "SELLING STOCKHOLDERS") propose severally to sell an
aggregate of 6,000,000 shares of the Securities (the aggregate of such 9,000,000
shares of the Securities to be sold by the Company and the Selling Stockholders
are herein referred to as the "FIRM SECURITIES") to the several underwriters
named in Schedule II hereto (the "UNDERWRITERS"), for whom Credit Suisse First
Boston LLC and J.P. Morgan Securities Inc. are acting as representatives (the
"REPRESENTATIVES"). Certain of the Selling Stockholders as specified in Schedule
I hereto also propose to sell to the Underwriters, at the option of the
Underwriters, an aggregate of not more than 1,350,000 additional shares of the
Securities, as set forth below (such 1,350,000 additional shares are herein
referred to as the "OPTIONAL SECURITIES"). The Firm Securities and the Optional
Securities are herein referred to collectively as "OFFERED SECURITIES." The
Company and the Selling Stockholders hereby agree with the Underwriters as
follows:

      2. Representations and Warranties of the Company and the Selling
Stockholders. (a) The Company represents and warrants to, and agrees with, the
several Underwriters that:

                  (i) A registration statement (No. 333-112718) relating to the
            Offered Securities, including a form of prospectus, has been filed
            with the Securities and Exchange Commission (the "COMMISSION") and
            either (A) has been declared effective under the Securities Act of
            1933, as amended (the "ACT"), and is not proposed to be amended or
            (B) is proposed to be amended by amendment or post-effective
            amendment. If such registration statement (the "INITIAL REGISTRATION
            STATEMENT") has been declared effective, either (A) an additional
            registration statement (the "ADDITIONAL REGISTRATION statement")
            relating to the Offered Securities may have been filed with the
            Commission pursuant to Rule 462(b) ("RULE 462(B)") under the Act
            and, if so filed, has become effective upon filing pursuant to such
            Rule and the Offered Securities all have been duly registered under
            the Act pursuant to the initial registration statement and, if
            applicable, the additional registration statement or (B) such an
            additional registration statement is proposed to be filed with the
            Commission pursuant to Rule 462(b) and will become effective upon
            filing pursuant to such Rule and upon such filing the Offered
            Securities will all have been duly registered under the Act pursuant
            to the initial registration statement and such additional
            registration statement. If the Company does not propose to amend the
            initial registration statement or if an additional registration
            statement has been filed and the Company does not propose to amend
            it, and if any post-effective amendment to either such registration
            statement has been filed with the Commission prior to the execution
            and delivery of this Agreement, the most recent amendment (if any)
            to each such registration statement has been declared effective by
            the Commission or has become effective upon filing pursuant to Rule
            462(c) ("RULE 462(C)") under the Act or, in the case of the
            additional registration statement, Rule 462(b). For purposes of this
            Agreement, the "EFFECTIVE TIME" with respect to the initial
            registration statement or, if filed prior to the execution and
            delivery of this Agreement, the additional registration statement
            means (A) if the Company has advised the Representatives that it
            does not propose to amend such registration statement, the date and
            time as of which such registration statement, or the most recent
            post-effective amendment thereto (if any) filed prior to the
            execution and delivery of this Agreement, was declared effective


                                       2

            by the Commission or has become effective upon filing pursuant to
            Rule 462(c), or (B) if the Company has advised the Representatives
            that it proposes to file an amendment or post-effective amendment to
            such registration statement, the date and time as of which such
            registration statement, as amended by such amendment or
            post-effective amendment, as the case may be, is declared effective
            by the Commission. If an additional registration statement has not
            been filed prior to the execution and delivery of this Agreement but
            the Company has advised the Representatives that it proposes to file
            one, the "EFFECTIVE TIME" with respect to such additional
            registration statement means the date and time as of which such
            registration statement is filed and becomes effective pursuant to
            Rule 462(b). The "EFFECTIVE DATE" with respect to the initial
            registration statement or the additional registration statement (if
            any) means the date of the Effective Time thereof. The initial
            registration statement, as amended at its Effective Time, including
            all information contained in the additional registration statement
            (if any) and deemed to be a part of the initial registration
            statement as of the Effective Time of the additional registration
            statement pursuant to the General Instructions of the Form on which
            it is filed and including all information (if any) deemed to be a
            part of the initial registration statement as of its Effective Time
            pursuant to Rule 430A(b) ("RULE 430A(B)") under the Act, is herein
            referred to as the "INITIAL REGISTRATION STATEMENT." The additional
            registration statement, as amended at its Effective Time, including
            the contents of the initial registration statement incorporated by
            reference therein and including all information (if any) deemed to
            be a part of the additional registration statement as of its
            Effective Time pursuant to Rule 430A(b), is herein referred to as
            the "ADDITIONAL REGISTRATION STATEMENT." The Initial Registration
            Statement and the Additional Registration are herein referred to
            collectively as the "REGISTRATION STATEMENTS" and individually as a
            "REGISTRATION STATEMENT." The form of prospectus relating to the
            Offered Securities, as first filed with the Commission pursuant to
            and in accordance with Rule 424(b) ("RULE 424(B)") under the Act or
            (if no such filing is required) as included in a Registration
            Statement, is herein referred to as the "PROSPECTUS." No document
            has been or will be prepared or distributed in reliance on Rule 434
            under the Act.

                  (ii) If the Effective Time of the Initial Registration
            Statement is prior to the execution and delivery of this Agreement:
            (A) on the Effective Date of the Initial Registration


                                       3

            Statement, the Initial Registration Statement conformed in all
            material respects to the applicable requirements of the Act and the
            rules and regulations of the Commission (the "RULES AND
            REGULATIONS") and did not include any untrue statement of a material
            fact or omit to state any material fact required to be stated
            therein or necessary to make the statements therein not misleading;
            (B) on the Effective Date of the Additional Registration Statement
            (if any), each Registration Statement conformed or will conform, in
            all material respects to the applicable requirements of the Act and
            the Rules and Regulations and did not include, or will not include,
            any untrue statement of a material fact and did not omit, or will
            not omit, to state any material fact required to be stated therein
            or necessary to make the statements therein not misleading; and (C)
            on the date of this Agreement, the Initial Registration Statement
            and, if the Effective Time of the Additional Registration Statement
            is prior to the execution and delivery of this Agreement, the
            Additional Registration Statement each conform, and at the time of
            filing of the Prospectus pursuant to Rule 424(b) or (if no such
            filing is required) at the Effective Date of the Additional
            Registration Statement in which the Prospectus is included, each
            Registration Statement and the Prospectus will conform, in all
            material respects to the applicable requirements of the Act and the
            Rules and Regulations, and none of such documents includes, or will
            include, any untrue statement of a material fact or omits, or will
            omit, to state any material fact required to be stated therein or
            necessary to make the statements therein not misleading.

                  If the Effective Time of the Initial Registration Statement is
            subsequent to the execution and delivery of this Agreement: on the
            Effective Date of the Initial Registration Statement, the Initial
            Registration Statement and the Prospectus will conform in all
            material respects to the applicable requirements of the Act and the
            Rules and Regulations, neither of such documents will include any
            untrue statement of a material fact or will omit to state any
            material fact required to be stated therein or necessary to make the
            statements therein not misleading, and no Additional Registration
            Statement has been or will be filed.

                  The two preceding paragraphs do not apply to statements in or
            omissions from a Registration Statement or the Prospectus based upon
            written information furnished to the Company by any Underwriter
            through the Representatives specifically for use therein, it being
            understood and agreed that the only such information is that
            described as such in Section 7(c) hereof.


                                       4

                  (iii) The Company has been duly incorporated and is an
            existing corporation in good standing under the laws of the State of
            Delaware, with power and authority (corporate and other) to own its
            properties and conduct its business as described in the Prospectus;
            and the Company is duly qualified to do business as a foreign
            corporation in good standing in all other jurisdictions in which its
            ownership or lease of property or the conduct of its business
            requires such qualification, except where the failure to so qualify
            as a foreign corporation would not, individually or in the
            aggregate, have a material adverse effect on the condition
            (financial or other), business, properties or results of operations
            of the Company and its subsidiaries taken as a whole (a "MATERIAL
            ADVERSE EFFECT"). The jurisdictions listed on Exhibit A to the
            opinion to be delivered to the Underwriters by Proskauer Rose LLP
            pursuant to Section 6(d) hereof and on Exhibit A to the opinion to
            be delivered to the Underwriters by [ ] pursuant to Section 6(e)
            hereof are the only jurisdictions in which the Company maintains an
            office or leases property.

                  (iv) Each subsidiary of the Company has been duly incorporated
            and is an existing corporation in good standing under the laws of
            the jurisdiction of its incorporation, with power and authority
            (corporate and other) to own its properties and conduct its business
            as described in the Prospectus; each subsidiary of the Company is
            duly qualified to do business as a foreign corporation in good
            standing in all other jurisdictions in which its ownership or lease
            of property or the conduct of its business requires such
            qualification, except where the failure to so qualify as a foreign
            corporation would not, individually or in the aggregate, have a
            Material Adverse Effect; the jurisdictions listed on Exhibit A to
            the opinion to be delivered to the Underwriters by Proskauer Rose
            LLP pursuant to Section 6(d) hereof and on Exhibit A to the opinion
            to be delivered to the Underwriters by [    ] pursuant to Section
            6(e) hereof are the only jurisdictions in which the Company's
            subsidiaries maintain an office or lease property; all of the issued
            and outstanding capital stock of each subsidiary of the Company has
            been duly authorized and validly issued and is fully paid and
            nonassessable and the capital stock of each subsidiary owned by the
            Company, directly or through subsidiaries, is owned free from liens,
            encumbrances and defects.

                  (v) The Securities (including the Offered Securities to be
            sold by the Selling Stockholders) outstanding prior to the issuance
            of the Offered Securities to be sold by the Company


                                       5

            have been duly authorized and are validly issued, fully paid and
            non-assessable and conform to the description thereof contained in
            the Prospectus.

                  (vi) The Offered Securities to be sold by the Company have
            been duly authorized and, when issued and delivered in accordance
            with the terms of this Agreement, will be validly issued, fully paid
            and non-assessable, and the issuance of such Offered Securities will
            not be subject to any preemptive or similar rights.

                  (vii) Except as disclosed in the Prospectus, there are no
            contracts, agreements or understandings between the Company and any
            person that would give rise to a valid claim against the Company or
            any Underwriter for a brokerage commission, finder's fee or other
            like payment in connection with this offering.

                  (viii) There are no contracts, agreements or understandings
            between the Company and any person granting such person the right to
            require the Company to file a registration statement under the 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 a Registration Statement or
            in any securities being registered pursuant to any other
            registration statement filed by the Company under the Act, other
            than the Sixth Amended and Restated Registration Rights Agreement
            dated as of April 4, 2002 (the "REGISTRATION RIGHTS AGREEMENT")
            among the Company and the Investors and Other Holders named therein.

                  (ix) The Securities have been approved for quotation subject
            to notice of issuance on the Nasdaq National Market.

                  (x) No consent, approval, authorization, or order of, or
            filing with, any governmental agency or body or any court is
            required to be obtained or made by the Company for the consummation
            of the transactions contemplated by this Agreement in connection
            with the sale of the Offered Securities, except such as have been
            obtained and made under the Act or under the Securities Exchange Act
            of 1934, as amended (the "EXCHANGE ACT"), such as have been obtained
            from the National Association of Securities Dealers, Inc. (the
            "NASD") and the Nasdaq National Market, and such as may be required
            under state securities laws.


                                       6

                  (xi) The execution, delivery and performance of this
            Agreement, and the consummation of the transactions herein
            contemplated will not result in a breach or violation of any of the
            terms and provisions of, or constitute a default under, any statute,
            any rule, regulation or order of any governmental agency or body or
            any court, domestic or foreign, having jurisdiction over the Company
            or any subsidiary of the Company or any of their properties, or any
            material agreement or instrument to which the Company or any such
            subsidiary is a party or by which the Company or any such subsidiary
            is bound or to which any of the properties of the Company or any
            such subsidiary is subject, or the charter or bylaws of the Company
            or any such subsidiary.

                  (xii) This Agreement has been duly authorized, executed and
            delivered by the Company.

                  (xiii) Except as disclosed in the Prospectus, the Company and
            its subsidiaries have good and marketable title to all real
            properties and all other properties and assets owned by them, in
            each case free from liens, encumbrances and defects that would
            materially affect the value thereof or materially interfere with the
            use made or to be made thereof by them; and except as disclosed in
            the Prospectus, the Company and its subsidiaries hold any leased
            real or personal property under valid and enforceable leases with no
            exceptions that would materially interfere with the use made or to
            be made thereof by them.

                  (xiv) The Company and its subsidiaries possess adequate
            certificates, authorities or permits issued by appropriate
            governmental agencies or bodies necessary to conduct the business
            now operated by them and have not received any notice of proceedings
            relating to the revocation or modification of any such certificate,
            authority or permit that, if determined adversely to the Company or
            any of its subsidiaries, would individually or in the aggregate have
            a Material Adverse Effect.

                  (xv) No labor dispute with the employees of the Company or any
            subsidiary exists or, to the knowledge of the Company, is imminent
            that might have a Material Adverse Effect.

                  (xvi) The Company and its subsidiaries own, possess the right
            to use or can acquire the right to use on reasonable terms, adequate
            trademarks, trade names and other rights to those inventions,
            know-how, patents, copyrights, confidential information and other
            intellectual property (collectively, the


                                       7

            "INTELLECTUAL PROPERTY RIGHTS") necessary to conduct the business
            now operated by them, or presently employed by them, and have not
            received any written notice of infringement with respect to any
            third party intellectual property rights that, if determined
            adversely to the Company or any of its subsidiaries, would
            individually or in the aggregate have a Material Adverse Effect.

                  (xvii) Except as disclosed in the Prospectus, neither the
            Company nor any of its subsidiaries is in violation of any statute,
            any rule, regulation, decision or order of any governmental agency
            or body or any court, domestic or foreign, relating to the use,
            disposal or release of hazardous or toxic substances or relating to
            the protection or restoration of the environment or human exposure
            to hazardous or toxic substances (collectively, the "ENVIRONMENTAL
            LAWS"), owns or operates any real property contaminated with any
            substance that is subject to any environmental laws, is liable for
            any off-site disposal or contamination pursuant to any environmental
            laws, or is subject to any claim relating to any environmental laws,
            which violation, contamination, liability or claim would
            individually or in the aggregate have a Material Adverse Effect; and
            the Company is not aware of any pending investigation which might
            lead to such a claim.

                  (xviii) Except as disclosed in the Prospectus, there are no
            pending actions, suits or proceedings against or affecting the
            Company, any of its subsidiaries or any of their respective
            properties that, if determined adversely to the Company or any of
            its subsidiaries, would individually or in the aggregate have a
            Material Adverse Effect, or would materially and adversely affect
            the ability of the Company to perform its obligations under this
            Agreement, or which are otherwise material in the context of the
            sale of the Offered Securities; and no such actions, suits or
            proceedings, to the Company's knowledge, have been threatened or are
            contemplated.

                  (xix) The financial statements, together with the related
            notes, included in each Registration Statement and the Prospectus
            present fairly the financial position of the Company and its
            consolidated subsidiaries as of the dates shown and their results of
            operations and cash flows for the periods shown, and such financial
            statements and related notes have been prepared in conformity with
            the generally accepted accounting principles in the United States
            applied on a consistent basis; all non-GAAP financial information,
            if any, included in each Registration


                                       8

            Statement and the Prospectus complies with the requirements of
            Regulation G and Item 10 of Regulation S-K under the Act; and the
            assumptions used in preparing the pro forma financial statements
            included in each Registration Statement and the Prospectus provide a
            reasonable basis for presenting the significant effects directly
            attributable to the transactions or events described therein, the
            related pro forma adjustments give appropriate effect to those
            assumptions, and the pro forma columns therein reflect the proper
            application of those adjustments to the corresponding historical
            financial statement amounts.

                  (xx) Except as disclosed in the Prospectus, since the date of
            the latest audited financial statements included in the Prospectus
            there has been no material adverse change, nor any development or
            event involving a prospective material adverse change, in the
            condition (financial or other), business, properties or results of
            operations of the Company and its subsidiaries taken as a whole,
            and, except as disclosed in or contemplated by the Prospectus, there
            has been no dividend or distribution of any kind declared, paid or
            made by the Company on any class of its capital stock.

                  (xxi) The Company is not and, after giving effect to the
            offering and sale of the Offered Securities and the application of
            the proceeds thereof as described in the Prospectus, will not be
            required to register as an "investment company" as such term is
            defined in the Investment Company Act of 1940, as amended.

                  (xxii) Any statistical and market-related data included in the
            Prospectus are based on or derived from sources that the Company
            believes to be reliable and accurate, and the Company has obtained
            the written consent to the use of such data from such sources to the
            extent required.

                  (xxiii) MarketAxess Corporation is registered under the
            Exchange Act as a broker-dealer and is a member in good standing of
            the NASD and neither the Company nor any other subsidiary is
            required to be so registered; MarketAxess Europe Limited is
            registered with the Financial Services Authority as a dealer and is
            a member in good standing of the Financial Services Authority and
            neither the Company nor any other subsidiary is required to be so
            registered; and to the extent required in connection with their
            respective businesses, each of the Company


                                       9

            and its subsidiaries is also registered as a broker-dealer in each
            state or other jurisdiction in which such registration is required.

                  (xxiv) Each of the Company and its subsidiaries maintain a
            system of internal accounting controls sufficient to provide
            reasonable assurance that (i) transactions are executed in
            accordance with management's general or specific authorizations;
            (ii) transactions are recorded as necessary to permit preparation of
            financial statements in conformity with generally accepted
            accounting principles and to maintain asset accountability; (iii)
            access to assets is permitted only in accordance with management's
            general or specific authorization and (iv) the recorded
            accountability for assets is compared with the existing assets at
            reasonable intervals and appropriate action is taken with respect to
            any differences. The Company maintains disclosure controls and
            procedures (as such term is defined in Rule 13a-14 under the
            Exchange Act) that are effective in ensuring that information
            required to be disclosed by the Company in the reports that it files
            or submits under the Exchange Act is recorded, processed, summarized
            and reported, within the time periods specified in the rules and
            forms of the Commission, including, without limitation, controls and
            procedures designed to ensure that information required to be
            disclosed by the Company in the reports that it files or submits
            under the Exchange Act is accumulated and communicated to the
            Company's management, including its principal executive officer or
            officers and its principal financial officer or officers, as
            appropriate to allow timely decisions regarding required disclosure.

      (b) Each Selling Stockholder severally represents and warrants to, and
agrees with, the several Underwriters that:

                  (i) If the Effective Time of the Initial Registration
            Statement is prior to the execution and delivery of this Agreement:
            (A) on the Effective Date of the Initial Registration Statement, the
            Initial Registration Statement did not include any untrue statement
            of a material fact or omit to state any material fact required to be
            stated therein or necessary to make the statements therein not
            misleading; (B) on the Effective Date of the Additional Registration
            Statement (if any), each Registration Statement did not include, or
            will not include, any untrue statement of a material fact and did
            not omit, or will not omit, to state any material fact required to
            be stated therein or necessary to make the statements therein not
            misleading and (C) on the date of this Agreement, neither the
            Initial Registration Statement nor, if


                                       10

            the Effective Time of the Additional Registration Statement is prior
            to the execution and delivery of this Agreement, the Additional
            Registration Statement includes, or will include, any untrue
            statement of a material fact or omits, or will omit, to state any
            material fact required to be stated therein or necessary to make the
            statements therein not misleading.

                  If the Effective Time of the Initial Registration Statement is
            subsequent to the execution and delivery of this Agreement: on the
            Effective Date of the Initial Registration Statement, neither the
            Initial Registration Statement nor the Prospectus will include any
            untrue statement of a material fact or will omit to state any
            material fact required to be stated therein or necessary to make the
            statements therein not misleading.

                  The two preceding paragraphs apply only to the extent that any
            statements in or omissions from a Registration Statement or the
            Prospectus are based on written information furnished to the Company
            by such Selling Stockholder specifically for use therein.

                  (ii) This Agreement has been duly authorized by each Selling
            Stockholder that is not a natural person, and has been duly executed
            and delivered by or on behalf of each Selling Stockholder.

                  (iii) The execution and delivery by such Selling Stockholder
            of, and the performance by such Selling Stockholder of its
            obligations under, this Agreement, the Custody Agreement signed by
            such Selling Stockholder and Wachovia Bank, N.A., as Custodian,
            relating to the deposit of the Offered Securities to be sold by such
            Selling Stockholder (the "CUSTODY AGREEMENT") and the Power of
            Attorney appointing certain individuals as such Selling
            Stockholder's attorneys-in-fact to the extent set forth therein,
            relating to the transactions contemplated hereby and by the
            Registration Statement (the "POWER OF ATTORNEY") will not contravene
            any provision of applicable law, or the certificate of incorporation
            or bylaws of such Selling Stockholder (if such Selling Stockholder
            is a corporation), or the partnership agreement or other similar
            agreement (if such Selling Stockholder is a partnership), or any
            agreement or other instrument binding upon such Selling Stockholder
            or any judgment, order or decree of any governmental body, agency or
            court having jurisdiction over such Selling Stockholder, and no
            consent, approval, authorization or order of, or qualification with,
            any governmental


                                       11

            body or agency or other regulatory body is required for the
            performance by such Selling Stockholder of its obligations under
            this Agreement or the Custody Agreement or Power of Attorney of such
            Selling Stockholder, except such as have been obtained and made
            under the Act or under the Exchange Act, such as have been obtained
            from the NASD and the Nasdaq National Market, and such as may be
            required under state securities laws.

                  (iv) Such Selling Stockholder has, and upon the delivery of,
            and payment for, the Offered Securities on each Closing Date
            hereunder, the several Underwriters will acquire, good and valid
            title to, the Offered Securities to be sold by such Selling
            Stockholder, free and clear of all security interests, claims,
            liens, equities or other encumbrances. In addition, such Selling
            Stockholder has the legal right and power, and all authorization and
            approval required by law, to enter into this Agreement, the Custody
            Agreement and the Power of Attorney and to sell, transfer and
            deliver the Offered Securities to be sold by such Selling
            Stockholder in respect of such Offered Securities.

                  (v) The Custody Agreement and the Power of Attorney have been
            duly authorized by each Selling Stockholder that is not a natural
            person, and have been duly executed and delivered by each Selling
            Stockholder and are valid and binding agreements of each Selling
            Stockholder, enforceable in accordance with their terms, subject to
            bankruptcy, insolvency, fraudulent transfer, reorganization,
            moratorium and similar laws of general applicability relating to or
            affecting creditors' rights and to general equity principles.

                  (vi) Upon payment for the Offered Securities to be sold by
            such Selling Stockholder pursuant to this Agreement, and assuming
            that no Underwriter has notice of any "adverse claim" within the
            meaning of Section 8-105 of the New York Uniform Commercial Code
            (the "UCC") to such Offered Securities, the Underwriters will
            acquire a valid security entitlement in respect of such Offered
            Securities.

                  (vii) Except as disclosed in the Prospectus, there are no
            contracts, agreements or understandings between such Selling
            Stockholder and any person that would give rise to a valid claim
            against such Selling Stockholder or any Underwriter for a brokerage
            commission, finder's fee or other like payment in connection with
            this offering.


                                       12

      3. Purchase, Sale and Delivery of Offered Securities. On the basis of the
representations, warranties and agreements herein contained, but subject to the
terms and conditions herein set forth, the Company and each Selling Stockholder
agree, severally and not jointly, to sell to each Underwriter, and each
Underwriter agrees, severally and not jointly, to purchase from the Company and
each Selling Stockholder, at a purchase price of $[    ] per share, that number
of Firm Securities (rounded up or down, as determined by the Representatives in
their discretion, in order to avoid fractions) obtained by multiplying 3,000,000
Firm Securities, in the case of the Company, and the number of Firm Securities
set forth opposite the name of such Selling Stockholder in Schedule I hereto, in
the case of a Selling Stockholder, in each case by a fraction the numerator of
which is the number of Firm Securities set forth opposite the name of such
Underwriter in Schedule II hereto and the denominator of which is the total
number of Firm Securities.

      Certificates in negotiable form for the Offered Securities to be sold by
the Selling Stockholders hereunder have been placed in custody, for delivery
under this Agreement, under Custody Agreements made with Wachovia Bank, N.A. as
custodian (the "CUSTODIAN"). Each Selling Stockholder agrees that the shares
represented by the certificates held in custody for the Selling Stockholders
under such Custody Agreements are subject to the interests of the Underwriters
hereunder, that the arrangements made by the Selling Stockholders for such
custody are to that extent irrevocable, and that the obligations of the Selling
Stockholders hereunder shall not be terminated by operation of law, whether by
the death of any individual Selling Stockholder or the occurrence of any other
event, or in the case of a trust, by the death of any trustee or trustees or the
termination of such trust. If any individual Selling Stockholder or any such
trustee or trustees should die, or if any other such event should occur, or if
any of such trusts should terminate, before the delivery of the Offered
Securities hereunder, certificates for such Offered Securities shall be
delivered by the Custodian in accordance with the terms and conditions of this
Agreement as if such death or other event or termination had not occurred,
regardless of whether or not the Custodian shall have received notice of such
death or other event or termination.

      The Company and the Custodian will deliver the Firm Securities to the
Representatives for the accounts of the Underwriters, against payment of the
purchase price in Federal (same day) funds by wire transfer to an account at a
bank acceptable to the Representatives made to the order of the Company, in the
case of 3,000,000 shares of Firm Securities, and made to the order of Wachovia
Bank, N.A., as Custodian, as agent for the Selling Stockholders, in the case of
6,000,000 shares of Firm Securities, at the offices of Davis Polk & Wardwell,
450 Lexington Avenue, New York, New York, at 10 A.M., New York time, on [    ],
2004, or at such other time not later than seven full business days thereafter
as the Representatives and the Company determine (such time is herein referred
to as the


                                       13

"FIRST CLOSING DATE"). For purposes of Rule 15c6-1 under the Exchange Act, the
First Closing Date (if later than the otherwise applicable settlement date)
shall be the settlement date for payment of funds and delivery of securities for
all the Offered Securities sold pursuant to the offering. The certificates for
the Firm Securities so to be delivered will be in definitive form, in such
denominations and registered in such names as the Representatives request and
will be made available for checking and packaging at the above offices of Davis
Polk & Wardwell at least 24 hours prior to the First Closing Date.

      In addition, upon written notice from the Representatives given to the
Company and certain of the Selling Stockholders, as indicated under the caption
"Number of Optional Securities to be Sold" in Schedule I hereto (the
"OVER-ALLOTMENT SELLING STOCKHOLDERS"), from time to time not more than 30 days
subsequent to the date of the Prospectus, the Underwriters may purchase all or
less than all of the Optional Securities at the purchase price per Security to
be paid for the Firm Securities. The Over-Allotment Selling Stockholders agree,
severally and not jointly, to sell to the Underwriters the respective numbers of
Optional Securities obtained by multiplying the number of Optional Securities
specified in such notice by a fraction the numerator of which is the number of
shares set forth opposite the names of such Over-Allotment Selling Stockholders
in Schedule I hereto under the caption "Number of Optional Securities to be
Sold" and the denominator of which is the total number of Optional Securities
(subject to adjustment by the Representatives to eliminate fractions). Such
Optional Securities shall be purchased from each Over-Allotment Selling
Stockholder for the account of each Underwriter in the same proportion as the
number of Firm Securities set forth opposite such Underwriter's name bears to
the total number of Firm Securities (subject to adjustment by the
Representatives to eliminate fractions) and may be purchased by the Underwriters
only for the purpose of covering over-allotments made in connection with the
sale of the Firm Securities. No Optional Securities shall be sold or delivered
unless the Firm Securities previously have been, or simultaneously are, sold and
delivered. The right to purchase the Optional Securities or any portion thereof
may be exercised from time to time and to the extent not previously exercised
may be surrendered and terminated at any time upon notice by the Representatives
to the Over-Allotment Selling Stockholders.

      Each time for the delivery of and payment for the Optional Securities
(such time is herein referred to as an "OPTIONAL CLOSING Date"), which may be
the First Closing Date (the First Closing Date and each Optional Closing Date,
if any, are herein referred to as a "CLOSING DATE"), shall be determined by the
Representatives but shall be not later than five full business days after
written notice of election to purchase Optional Securities is given. The
Custodian will deliver the Optional Securities being purchased on each Optional
Closing Date to the Representatives for the accounts of the several
Underwriters, against payment of the purchase price therefor in Federal (same
day) funds by wire transfer to an


                                       14

account at a bank acceptable to the Representatives made to the order of [the
Over-Allotment Selling Stockholders], at the above offices of Davis Polk &
Wardwell. The certificates for the Optional Securities being purchased on each
Optional Closing Date will be in definitive form, in such denominations and
registered in such names as the Representatives request upon reasonable notice
prior to such Optional Closing Date and will be made available for checking and
packaging at the above offices of Davis Polk & Wardwell at a reasonable time in
advance of such Optional Closing Date.

      4. Offering by Underwriters. It is understood that the several
Underwriters propose to offer the Offered Securities for sale to the public as
set forth in the Prospectus.

      5. Certain Agreements of the Company and the Selling Stockholders. The
Company and the Selling Stockholders agree with the several Underwriters that:

      (a) If the Effective Time of the Initial Registration Statement is prior
to the execution and delivery of this Agreement, the Company will file the
Prospectus with the Commission pursuant to and in accordance with subparagraph
(1) (or, if applicable and if consented to by the Representatives, subparagraph
(4)) of Rule 424(b) not later than the earlier of (A) the second business day
following the execution and delivery of this Agreement or (B) the fifteenth
business day after the Effective Date of the Initial Registration Statement.

      The Company will advise the Representatives promptly of any such filing
      pursuant to Rule 424(b). If the Effective Time of the Initial Registration
      Statement is prior to the execution and delivery of this Agreement and an
      additional registration statement is necessary to register a portion of
      the Offered Securities under the Act, but the Effective Time thereof has
      not occurred as of such execution and delivery, the Company will file the
      additional registration statement or, if filed, will file a post-effective
      amendment thereto with the Commission pursuant to and in accordance with
      Rule 462(b) on or prior to 10:00 P.M., New York time, on the date of this
      Agreement or, if earlier, on or prior to the time the Prospectus is
      printed and distributed to any Underwriter, or will make such filing at
      such later date as shall have been consented to by the Representatives.

      (b) The Company will advise the Representatives promptly of any proposal
to amend or supplement the initial or any additional registration statement as
filed or the related prospectus or the Initial Registration Statement, the
Additional Registration Statement (if any) or the Prospectus and will not
efffect


                                       15

such amendment or supplement without the Representatives' consent; and the
Company will also advise the Representatives promptly of the effectiveness of
each Registration Statement (if its Effective Time is subsequent to the
execution and delivery of this Agreement) and of any amendment or supplement of
a Registration Statement or the Prospectus and of the institution by the
Commission of any stop order proceedings in respect of a Registration Statement
and will use its best efforts to prevent the issuance of any such stop order and
to obtain as soon as possible its lifting, if issued.

      (c) If, at any time when a prospectus relating to the Offered Securities
is required to be delivered under the Act in connection with sales by any
Underwriter or dealer, any event occurs 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 to make the statements
therein, in the light of the circumstances under which they were made, not
misleading, or if it is necessary at any time to amend the Prospectus to comply
with the Act, the Company will promptly notify the Representatives of such event
and will promptly prepare and file with the Commission, at its own expense, an
amendment or supplement which will correct such statement or omission or an
amendment which will effect such compliance. Neither the Representatives'
consent to, nor the Underwriters' delivery of, any such amendment or supplement
shall constitute a waiver of any of the conditions set forth in Section 6
hereof.

      (d) As soon as practicable, but not later than the Availability Date (as
defined below), the Company will make generally available to its securityholders
an earning statement covering a period of at least 12 months beginning after the
Effective Date of the Initial Registration Statement (or, if later, the
Effective Date of the Additional Registration Statement) which will satisfy the
provisions of Section 11(a) of the Act. For the purpose of the preceding
sentence, the "AVAILABILITY DATE" means the 45th day after the end of the fourth
fiscal quarter following the fiscal quarter that includes such Effective Date,
except that, if such fourth fiscal quarter is the last quarter of the Company's
fiscal year, "AVAILABILITY DATE" means the 90th day after the end of such fourth
fiscal quarter.

      (e) The Company will furnish to the Representatives copies of each
Registration Statement (three of which will be signed and will include all
exhibits), each related preliminary prospectus, and, so long as a prospectus
relating to the Offered Securities is required to be delivered under the Act in
connection with sales by any Underwriter or dealer, the Prospectus and all
amendments and supplements to such documents, in each case in such quantities as
the Representatives request. The Prospectus shall be so furnished on or prior to
3:00 P.M., New York time, on the business day following the later of the
execution and delivery of this Agreement or the Effective Time of the Initial
Registration Statement. All other such documents shall be so furnished as soon
as available.


                                       16

The Company will pay the expenses of printing and distributing to the
Underwriters all such documents.

      (f) The Company will arrange for the qualification of the Offered
Securities for sale under the laws of such jurisdictions as the Representatives
designate and will continue such qualifications in effect so long as required
for the distribution.

      (g) The Company agrees with the several Underwriters that the Company will
pay all expenses incident to the performance of the obligations of the Company
and the Selling Stockholders, as the case may be, under this Agreement
including: (i) the fees, disbursements and expenses of the Company's counsel,
the Company's accountants and one counsel for the Selling Stockholders in
connection with the registration and delivery of the Offered Securities under
the Act and all other fees or expenses in connection with the preparation and
filing of a Registration Statement, any preliminary prospectus, the Prospectus
and amendments and supplements to any of the foregoing, including all printing
costs associated therewith, and the mailing and delivering of copies thereof to
the Underwriters and dealers; provided that the Underwriters shall not be
obligated to pay the fees, disbursements and expenses of any counsel for the
Selling Stockholders; (ii) the cost of printing or producing any Blue Sky
memorandum in connection with the offer and sale of the Offered Securities under
state securities laws and all expenses in connection with the qualification of
the Offered Securities for offer and sale under state securities laws, including
filing fees and the reasonable fees and disbursements of counsel for the
Underwriters in connection with such qualification and in connection with the
Blue Sky memorandum; (iii) all filing fees incurred in connection with the
review and qualification of the offering of the Offered Securities by the NASD;
(iv) any travel expenses of the Company's officers and employees and any other
expenses of the Company in connection with attending or hosting meetings with
prospective purchasers of the Offered Securities, including the cost of any
aircraft chartered in connection with attending or hosting such meetings; (v)
any transfer taxes on the sale by the Selling Stockholders of the Offered
Securities to the Underwriters; (vi) all fees and expenses in connection with
the preparation and filing of the registration statement on Form 8-A relating to
the Securities and all costs and expenses incident to quoting the Offered
Securities on the Nasdaq National Market; (vii) the cost of printing
certificates representing the Offered Securities and (viii) the costs and
charges of any transfer agent, registrar or depositary; provided, however, that
each Selling Stockholder shall be responsible for the underwriting discounts and
commissions applicable to the shares sold by such Selling Stockholder. The
provisions of this Section 5(g) are intended to relieve the Underwriters from
the payment of the expenses and costs which the Company agrees to pay, but shall
not affect any agreement which the Company and the Selling Stockholders may
make, or may have made, for the sharing of any of such expenses and costs.


                                       17

      (h) For a period of 180 days after the date of the initial public offering
of the Offered Securities, the Company shall not offer, sell, contract to sell,
pledge or otherwise dispose of, directly or indirectly, or file with the
Commission a registration statement under the Act relating to, any additional
shares of the Securities or securities convertible into or exchangeable or
exercisable for any Securities, or publicly disclose the intention to make any
such offer, sale, pledge, disposition or filing, without, in each case, the
prior written consent of the Representatives, except (i) the filing of a
registration statement on Form S-8, (ii) issuances of Securities pursuant to the
conversion of convertible securities or the exercise of warrants or stock
options, in each case outstanding on the date hereof and (iii) grants of
employee stock options pursuant to the terms of a plan in effect on the date
hereof and disclosed in the Prospectus.

      (i) For a period of 180 days after the date of the initial public offering
of the Offered Securities, each Selling Stockholder shall not offer, sell,
contract to sell, pledge or otherwise dispose of, directly or indirectly, any
additional shares of the Securities or securities convertible into or
exchangeable or exercisable for any Securities, enter into a transaction which
would have the same effect, or enter into any swap, hedge or other arrangement
that transfers, in whole or in part, any of the economic consequences of
ownership of the Securities, whether any such aforementioned transaction is to
be settled by delivery of the Securities or such other securities, in cash or
otherwise, or publicly disclose the intention to make any such offer, sale,
pledge or disposition, or enter into any such transaction, swap, hedge or other
arrangement, or make any demand for or exercise any right with respect to, the
registration of any Securities or any security convertible into or exercisable
or exchangeable for the Securities, without, in each case, the prior written
consent of the Representatives.

      (j) For a period of 180 days after the date of the initial public offering
of the Offered Securities, the Company shall not waive the lock-up restrictions
contained in (i) the Registration Rights Agreement, (ii) the Stock Restriction
Agreement dated March 23, 2001 among the Company and Holders named therein and
(iii) any stock option plan adopted by the Company, without, in each case, the
prior written consent of the Representatives.

      6. Conditions of the Obligations of the Underwriters. The obligations of
the several Underwriters to purchase and pay for the Firm Securities on the
First Closing Date and the Optional Securities to be purchased on each Optional
Closing Date will be subject to the accuracy of the representations and
warranties on the part of the Company and the Selling Stockholders herein, to
the accuracy of the statements of officers of the Company made pursuant to the
provisions hereof, to the performance by the Company and the Selling
Stockholders of their obligations hereunder and to the following additional
conditions precedent:


                                       18

      (a) The Representatives shall have received a letter, dated the date of
delivery thereof (which, if the Effective Time of the Initial Registration
Statement is prior to the execution and delivery of this Agreement, shall be on
or prior to the date of this Agreement or, if the Effective Time of the Initial
Registration Statement is subsequent to the execution and delivery of this
Agreement, shall be prior to the filing of the amendment or post-effective
amendment to the registration statement to be filed shortly prior to such
Effective Time), of PricewaterhouseCoopers LLP confirming that they are
independent public accountants within the meaning of the Act and the applicable
published Rules and Regulations thereunder and stating to the effect that:

                  (i) in their opinion the financial statements examined by them
            and included in the Registration Statements comply as to form in all
            material respects with the applicable accounting requirements of the
            Act and the related published Rules and Regulations;

                  (ii) they have performed the procedures specified by the
            American Institute of Certified Public Accountants for a review of
            interim financial information as described in Statement of Auditing
            Standards No. 100, Interim Financial Information, on the unaudited
            financial statements included in the Registration Statements;

                  (iii) on the basis of the review referred to in clause (ii)
            above, a reading of the latest available interim financial
            statements of the Company, inquiries of officials of the Company who
            have responsibility for financial and accounting matters and other
            specified procedures, nothing came to their attention that caused
            them to believe that:

                        (A) the unaudited financial statements included in the
                  Registration Statements do not comply as to form in all
                  material respects with the applicable accounting requirements
                  of the Act and the related published Rules and Regulations or
                  any material modifications should be made to such unaudited
                  financial statements for them to be in conformity with
                  generally accepted accounting principles;

                        (B) the unaudited consolidated revenues, income (loss)
                  from operations, net income (loss) and net income (loss) per
                  share amounts for the three-month periods ended March 31, 2003
                  and 2004 included in the Prospectus do not agree with the
                  amounts set forth in the


                                       19

                  unaudited consolidated financial statements for those same
                  periods or were not determined on a basis substantially
                  consistent with that of the corresponding amounts in the
                  audited statements of income;

                        (C) at the date of the latest available balance sheet
                  read by such accountants, or at a subsequent specified date
                  not more than three business days prior to the date of this
                  Agreement, there was any change in the capital stock or any
                  increase in short-term indebtedness or long-term debt of the
                  Company and its consolidated subsidiaries or, at the date of
                  the latest available balance sheet read by such accountants,
                  there was any decrease in consolidated net assets, as compared
                  with amounts shown on the latest balance sheet included in the
                  Prospectus; or

                        (D) for the period from the closing date of the latest
                  income statement included in the Prospectus to the closing
                  date of the latest available income statement read by such
                  accountants there were any decreases, as compared with the
                  corresponding period of the previous year, in consolidated
                  revenues or income (loss) from operations or in the total or
                  per share amounts of consolidated net income (loss);

            except in all cases set forth in clauses (C) and (D) above, for
            changes, increases or decreases which the Prospectus discloses have
            occurred or may occur or which are described in such letter; and

                  (iv) they have compared specified dollar amounts (or
            percentages derived from such dollar amounts) and other financial
            information contained in the Registration Statements (in each case
            to the extent that such dollar amounts, percentages and other
            financial information are derived from the general accounting
            records of the Company and its subsidiaries subject to the internal
            controls of the Company's accounting system or are derived directly
            from such records by analysis or computation) with the results
            obtained from inquiries, a reading of such general accounting
            records and other procedures specified in such letter and have found
            such dollar amounts, percentages and other financial information to
            be in agreement with such results, except as otherwise specified in
            such letter.


                                       20

            For purposes of Section 6(a) hereof, (i) if the Effective Time of
      the Initial Registration Statement is subsequent to the execution and
      delivery of this Agreement, the "REGISTRATION STATEMENTS" shall mean the
      initial registration statement as proposed to be amended by the amendment
      or post-effective amendment to be filed shortly prior to its Effective
      Time, (ii) if the Effective Time of the Initial Registration Statement is
      prior to the execution and delivery of this Agreement but the Effective
      Time of the Additional Registration Statement is subsequent to such
      execution and delivery, the "REGISTRATION STATEMENTS" shall mean the
      Initial Registration Statement and the additional registration statement
      as proposed to be filed or as proposed to be amended by the post-effective
      amendment to be filed shortly prior to its Effective Time and (iii) the
      "PROSPECTUS" shall mean the prospectus included in the Registration
      Statements.

      (b) If the Effective Time of the Initial Registration Statement is not
prior to the execution and delivery of this Agreement, such Effective Time shall
have occurred not later than 10:00 P.M., New York time, on the date of this
Agreement or such later date as shall have been consented to by the
Representatives. If the Effective Time of the Additional Registration Statement
(if any) is not prior to the execution and delivery of this Agreement, such
Effective Time shall have occurred not later than 10:00 P.M., New York time, on
the date of this Agreement or, if earlier, the time the Prospectus is printed
and distributed to any Underwriter, or shall have occurred at such later date as
shall have been consented to by the Representatives. If the Effective Time of
the Initial Registration Statement is prior to the execution and delivery of
this Agreement, the Prospectus shall have been filed with the Commission in
accordance with the Rules and Regulations and Section 5(a) hereof. Prior to such
Closing Date, no stop order suspending the effectiveness of a Registration
Statement shall have been issued and no proceedings for that purpose shall have
been instituted or, to the knowledge of any Selling Stockholder, the Company or
the Representatives, shall be contemplated by the Commission.

      (c) Subsequent to the execution and delivery of this Agreement, there
shall not have occurred: (i) any change, or any development or event involving a
prospective change, in the condition (financial or other), business, properties
or results of operations of the Company and its subsidiaries taken as one
enterprise which, in the judgment of a majority in interest of the Underwriters
including the Representatives, is material and adverse and makes it impractical
or inadvisable to proceed with completion of the public offering or the sale of
and payment for the Offered Securities; (ii) any downgrading in the rating of
any debt securities of the Company by any "nationally recognized statistical
rating organization" (as defined for purposes of Rule 436(g) under the Act), or
any public announcement that any such organization has under surveillance or
review its rating of any debt securities of the Company (other than an
announcement with positive implications of a


                                       21

possible upgrading, and no implication of a possible downgrading, of such
rating); (iii) any change in U.S. or international financial, political or
economic conditions or currency exchange rates or exchange controls as would, in
the judgment of a majority in interest of the Underwriters including the
Representatives, be likely to prejudice materially the success of the proposed
issue, sale or distribution of the Offered Securities, whether in the primary
market or in respect of dealings in the secondary market; (iv) any material
suspension or material limitation of trading in securities generally on the New
York Stock Exchange or the Nasdaq National Market, or any setting of minimum
prices for trading on such exchange; (v) any suspension of trading of any
securities of the Company on any exchange or in the over-the-counter market;
(vi) any banking moratorium declared by U.S. Federal or New York authorities;
(vii) any major disruption of settlements of securities or clearance services in
the United States; or (viii) any attack on, outbreak or escalation of
hostilities or act of terrorism involving the United States, any declaration of
war by Congress or any other national or international calamity or emergency if,
in the judgment of a majority in interest of the Underwriters including the
Representatives, the effect of any such attack, outbreak, escalation, act,
declaration, calamity or emergency makes it impractical or inadvisable to
proceed with completion of the public offering or the sale of and payment for
the Offered Securities.

      (d) The Representatives shall have received an opinion, dated such Closing
Date, of Proskauer Rose LLP, counsel for the Company, to the effect that:

                  (i) The Company has been duly incorporated and is an existing
            corporation in good standing under the laws of the State of
            Delaware, with corporate power and authority to own its properties
            and conduct its business as described in the Prospectus; and the
            Company is duly qualified to do business as a foreign corporation in
            good standing in each jurisdiction listed on Exhibit A to such
            opinion.

                  (ii) Each U.S. subsidiary of the Company has been duly
            incorporated and is an existing corporation in good standing under
            the laws of the jurisdiction of its incorporation, with corporate
            power and authority to own its properties and conduct its business
            as described in the Prospectus; each U.S. subsidiary of the Company
            is duly qualified to do business as a foreign corporation in good
            standing in each jurisdiction listed on Exhibit A to such opinion;
            all of the issued and outstanding capital stock of each U.S.
            subsidiary of the Company has been duly authorized and validly
            issued and, to such counsel's knowledge, is fully paid and
            nonassessable; and the capital stock of each U.S. subsidiary owned
            by the Company, directly or through subsidiaries, is owned free from
            liens, encumbrances and defects.


                                       22

                  (iii) The Securities (including the Offered Securities to be
            sold by the Selling Stockholders) outstanding prior to the issuance
            of the Offered Securities to be sold by the Company have been duly
            authorized and are validly issued, fully paid and non-assessable and
            conform in all material respects to the description thereof
            contained in the Prospectus.

                  (iv) The Offered Securities to be sold by the Company have
            been duly authorized and, when issued and delivered in accordance
            with the terms of this Agreement, will be validly issued, fully paid
            and non-assessable, and the issuance of such Offered Securities will
            not be subject to any preemptive or similar rights.

                  (v) To such counsel's knowledge, other than the Registration
            Rights Agreement, there are no contracts, agreements or
            understandings between the Company and any person granting such
            person the right to require the Company to file a registration
            statement under the 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 Act.

                  (vi) The Company is not and, after giving effect to the
            offering and sale of the Offered Securities and the application of
            the proceeds thereof as described in the Prospectus, will not be
            required to register as an "investment company" as such term is
            defined in the Investment Company Act of 1940, as amended.

                  (vii) No consent, approval, authorization or order of, or
            filing with, any governmental agency or body or any court is
            required to be obtained or made by the Company for the consummation
            of the transactions contemplated by this Agreement or the Custody
            Agreement in connection with the sale of the Offered Securities,
            except such as have been obtained and made under the Act, the
            Exchange Act, the rules of the NASD, the rules of the Nasdaq
            National Market and such as may be required under state securities
            laws.

                  (viii) The execution, delivery and performance by the Company
            of this Agreement and the consummation of the transactions herein
            contemplated will not result in a breach or violation of any of the
            terms and provisions of, or constitute a


                                       23

            default under, any applicable United States federal law, Delaware
            corporate law or New York State law, rule, regulation or order of
            any governmental agency or body or any court having jurisdiction
            over the Company or any U.S. subsidiary of the Company or any of
            their properties that, in such counsel's experience, is normally
            applicable to general business corporations in relation to
            transactions of the type contemplated by this Agreement, or the
            charter or bylaws of the Company or any U.S. subsidiary of the
            Company or any agreement or other instrument to which the Company or
            any U.S. subsidiary is a party and which is filed as an exhibit to
            the Registration Statement.

                  (ix) The Initial Registration Statement was declared effective
            under the Act as of the date and time specified in such opinion, the
            Additional Registration Statement, if any, was filed and became
            effective under the Act as of the date and time, if determinable,
            specified in such opinion, the Prospectus either was filed with the
            Commission pursuant to the subparagraph of Rule 424(b) specified in
            such opinion on the date specified therein or was included in the
            Initial Registration Statement or the Additional Registration
            Statement, as the case may be, and, based solely upon the oral
            advice of the Commission, no stop order suspending the effectiveness
            of a Registration Statement or any part thereof has been issued and
            no proceedings for that purpose have been instituted or are pending
            or contemplated under the Act; and each Registration Statement and
            the Prospectus, and each amendment or supplement thereto, as of
            their respective effective or issue dates, complied as to form in
            all material respects with the applicable requirements of the Act
            and the Rules and Regulations; in the course of the preparation of
            the Registration Statement and the Prospectus, such counsel has
            participated in conferences with certain officers of the Company,
            with representatives of the independent or certified public
            accountants for the Company and with representatives of the
            Representatives and counsel for the Underwriters at which the
            contents of the Registration Statement and the Prospectus were
            discussed and, although such counsel need not pass upon or assume
            any responsibility for the accuracy, completeness or fairness of the
            statements contained in the Registration Statement or the Prospectus
            (other than as expressly set forth in such opinion), on the basis of
            the foregoing, nothing has come to such counsel's attention that
            would lead them to believe that the Registration Statement (other
            than the financial statements and related notes thereto and the
            other financial and accounting data


                                       24

            set forth therein or omitted therefrom, as to which such counsel
            need express no view), as of its effective date, contained an untrue
            statement of a material fact or omitted to state a material fact
            required to be stated therein or necessary to make the statements
            therein not misleading or that the Prospectus (other than the
            financial statements and related notes thereto and the other
            financial and accounting data set forth therein or omitted
            therefrom, as to which such counsel need express no view), as of its
            date and the Closing Date, contained or contains an untrue statement
            of a material fact or omitted or omits to state a material fact
            necessary to make the statements therein, in light of the
            circumstances under which they were made, not misleading; the
            descriptions in the Registration Statements and Prospectus of
            statutes, legal and governmental proceedings and contracts and other
            documents are accurate and fairly present the information required
            to be shown; such counsel do not know of any legal or governmental
            proceedings required to be described in a Registration Statement or
            the Prospectus which are not described as required or of any
            contracts or documents of a character required to be described in a
            Registration Statement or the Prospectus or to be filed as exhibits
            to a Registration Statement which are not described and filed as
            required; it is understood that such counsel need express no opinion
            as to the financial statements or other financial data contained in
            the Registration Statements or the Prospectus.

                  (x) This Agreement has been duly authorized, executed and
            delivered by the Company.

      (e) [The Representatives shall have received an opinion, dated such
Closing Date, of      , counsel for the Company with respect to the Company's
wholly owned subsidiary, MarketAxess Europe (the "Subsidiary"), to the effect
that:

                  (i) The Subsidiary has been duly incorporated and is an
            existing corporation in good standing under the laws of the
            jurisdiction of its incorporation, with corporate power and
            authority to own its properties and conduct its business as
            described in the Prospectus; the Subsidiary is duly qualified to do
            business as a foreign corporation in good standing in all other
            jurisdictions in which its ownership or lease of property or the
            conduct of its business requires such qualification; all of the
            issued and outstanding capital stock of the Subsidiary has been duly
            authorized and validly issued and, to such counsel's knowledge, is
            fully paid and nonassessable; and, to such


                                       25

            counsel's knowledge, the capital stock of the Subsidiary owned by
            the Company, directly or through subsidiaries, is owned free from
            liens, encumbrances and defects.

                  (ii) The execution, delivery and performance by the Company of
            this Agreement and the consummation of the transactions herein
            contemplated will not result in a breach or violation of any of the
            terms and provisions of, or constitute a default under any statute,
            any rule, regulation or order known to such counsel of any
            governmental agency or body or any court having jurisdiction over
            the Subsidiary or any of its properties, or any agreement or
            instrument to which the Subsidiary is a party or by which the
            Subsidiary is bound or to which any of the properties of the
            Subsidiary is subject or the charter or bylaws of the Subsidiary.]

      (f) The Representatives shall have received either (i) the opinion
contemplated in Annex II to the Power of Attorney executed and delivered by each
Selling Stockholder or (ii) an opinion, dated such closing date, of Proskauer
Rose LLP, counsel for certain of the Selling Stockholders, to the effect that:

                  (i) Each Selling Stockholder has full right, power and
            authority to enter into the Power of Attorney, dated [    ], 2004,
            of such Selling Stockholder, the Custody Agreement, dated [    ],
            2004, between such Selling Stockholder and the Custodian, and this
            Agreement.

                  (ii) The execution, delivery and performance of each of the
            Power of Attorney, the Custody Agreement and this Agreement by each
            Selling Stockholder and the consummation by each Selling Stockholder
            of the transactions contemplated thereby will not conflict with or
            result in a breach or violation of any of the terms or provisions
            of, or constitute a default under, any provision of applicable
            United States federal law, Delaware corporate law or New York State
            law, or the certificate of incorporation or bylaws of such Selling
            Stockholder (if such Selling Stockholder is a corporation), or the
            partnership agreement or other similar agreement (if such Selling
            Stockholder is a partnership), or, to such counsel's knowledge, any
            material indenture, mortgage, deed of trust, loan agreement or other
            agreement or instrument known to such counsel to which any Selling
            Stockholder is a party or by which any Selling Stockholder is bound
            or to which any of the property or assets of any Selling Stockholder
            is subject (each of which agreements and instruments shall be listed
            in such opinion), or, to such counsel's


                                       26

            knowledge, any order, rule or regulation of any United States
            federal, Delaware corporate or New York State court or governmental
            agency or body having jurisdiction over any Selling Stockholder or
            the property or assets of any Selling Stockholder; and, except for
            the registration of the Offered Securities 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
            distribution of the Offered Securities by the Underwriters, no
            consent, approval, authorization or order of, or filing or
            registration with, any such United States federal, Delaware
            corporate or New York State court or governmental agency or body is
            required for the execution, delivery and performance of the Power of
            Attorney, the Custody Agreement or this Agreement by any Selling
            Stockholder and the consummation by each Selling Stockholder of the
            transactions contemplated thereby.

                  (iii) This Agreement has been duly authorized by each Selling
            Stockholder that is not a natural person, and has been duly executed
            and delivered by or on behalf of each Selling Stockholder.

                  (iv) Each of the Power of Attorney and the Custody Agreement
            has been duly authorized by each Selling Stockholder that is not a
            natural person, and has been duly executed and delivered by each
            Selling Stockholder, and is a valid and binding agreement of such
            Selling Stockholder, enforceable in accordance with its terms,
            subject to bankruptcy, insolvency, fraudulent transfer,
            reorganization, moratorium and similar laws of general applicability
            relating to or affecting creditors' rights and to general equity
            principles.

                  (v) Upon payment for, and delivery of, the shares of Stock to
            be sold by the Selling Stockholders under this Agreement in
            accordance with the terms hereof, assuming that such Underwriters
            have no notice of any adverse claim (within the meaning of Section
            8-105 of the UCC) to such shares of Stock or any security
            entitlement in respect thereof, (A) the Underwriters shall be a
            protected purchaser of such shares of Stock within the meaning of
            Section 8-303 of the UCC, (B) under Section 8-501 of the UCC, the
            Underwriters will acquire a security entitlement in respect of such
            shares of Stock and (C) no action based on an adverse claim (as
            defined in Section 8-102 of


                                       27

            the UCC) to such security entitlement may be validly asserted
            against the Underwriters.

      (g) The Representatives shall have received from Davis Polk & Wardwell,
counsel for the Underwriters, such opinion or opinions, dated such Closing Date,
with respect to the validity of the Offered Securities delivered on such Closing
Date, the Registration Statements, the Prospectus and other related matters as
the Representatives may require, and the Selling Stockholders and the Company
shall have furnished to such counsel such documents as they may reasonably
request for the purpose of enabling them to pass upon such matters.

      (h) The Representatives shall have received a certificate, dated such
Closing Date, of the President or any Vice President and a principal financial
or accounting officer of the Company in which such officers, to the best of
their knowledge after reasonable investigation, shall state that: (i) the
representations and warranties of the Company in this Agreement are true and
correct; (ii) the Company has complied with all agreements and satisfied all
conditions on its part to be performed or satisfied hereunder at or prior to
such Closing Date; (iii) no stop order suspending the effectiveness of any
Registration Statement has been issued and no proceedings for that purpose have
been instituted or are contemplated by the Commission; (iv) the Additional
Registration Statement (if any) satisfying the requirements of subparagraphs (1)
and (3) of Rule 462(b) was filed pursuant to Rule 462(b), including payment of
the applicable filing fee in accordance with Rule 111(a) or (b) under the Act,
prior to the time the Prospectus was printed and distributed to any Underwriter;
and (v) subsequent to the date of the most recent financial statements in the
Prospectus, there has been no material adverse change, nor any development or
event involving a prospective material adverse change, in the condition
(financial or other), business, properties or results of operations of the
Company and its subsidiaries taken as a whole except as set forth in the
Prospectus or as described in such certificate.

      (i) The Representatives shall have received a letter, dated such Closing
Date, of PricewaterhouseCoopers LLP which meets the requirements of Section 6(a)
hereof, except that the specified date referred to in such subsection will be a
date not earlier than the date hereof for purposes of the letter delivered on
the First Closing Date and a date not more than three days prior to any Optional
Closing Date for purposes of the letter delivered on any Optional Closing Date.

      (j) On or prior to the date of this Agreement, the Representatives shall
have received lock-up letters from (i) each of the executive officers and
directors of the Company, (ii) each of the holders of equity securities of the
Company (including holders of options and warrants to purchase equity securities
of the Company), other than executive officers and directors and (iii) each of
the equity holders who are Selling Stockholders, in each case except as
otherwise agreed to by the Representatives on behalf of the Underwriters.


                                       28

      (k) The Custodian will deliver to the Representatives a letter stating
that they will deliver to each Selling Stockholder a United States Treasury
Department Form 1099 (or other applicable form or statement specified by the
United States Treasury Department regulations in lieu thereof) on or before
January 31 of the year following the date of this Agreement.

      (l) No Underwriter shall have notice of an "adverse claim" on the Offered
Securities within the meaning of Section 8-102 of the UCC.

The Selling Stockholders and the Company will furnish the Representatives with
such conformed copies of such opinions, certificates, letters and documents as
the Representatives reasonably request. The Representatives may in their sole
discretion waive on behalf of the Underwriters compliance with any conditions to
the obligations of the Underwriters hereunder, whether in respect of an Optional
Closing Date or otherwise.

      7. Indemnification and Contribution. (a) The Company will indemnify and
hold harmless each Underwriter, its partners, members, directors and officers
and each person, if any, who controls such Underwriter within the meaning of
Section 15 of the Act, against any losses, claims, damages or liabilities, joint
or several, to which such Underwriter may become subject, under the Act or
otherwise, insofar as such losses, claims, damages or liabilities (or actions in
respect thereof) arise out of or are based upon any untrue statement or alleged
untrue statement of any material fact contained in any Registration Statement,
the Prospectus, or any amendment or supplement thereto, or any related
preliminary prospectus, or arise out of or are based upon the omission or
alleged omission to state therein a material fact required to be stated therein
or necessary to make the statements therein not misleading, and will reimburse
each Underwriter for any legal or other expenses reasonably incurred by such
Underwriter in connection with investigating or defending any such loss, claim,
damage, liability or action as such expenses are incurred; provided that the
Company will not be liable in any such case to the extent that any such loss,
claim, damage or liability arises out of or is based upon an untrue statement or
alleged untrue statement in or omission or alleged omission from any of such
documents in reliance upon and in conformity with written information furnished
to the Company by any Underwriter through the Representatives specifically for
use therein, it being understood and agreed that the only such information
furnished by any Underwriter consists of the information described as such in
subsection (c) below; and provided, further, that with respect to any untrue
statement or alleged untrue statement in or omission or alleged omission from
any preliminary prospectus the indemnity agreement contained in this subsection
(a) shall not inure to the benefit of any Underwriter from whom the person
asserting any such losses, claims, damages or liabilities purchased the Offered
Securities concerned, to the extent that a prospectus relating to such Offered
Securities was required to be delivered by such Underwriter under the Act in
connection with such purchase and any such loss,


                                       29

claim, damage or liability of such Underwriter results from the fact that there
was not sent or given to such person, at or prior to the written confirmation of
the sale of such Offered Securities to such person, a copy of the Prospectus if
the Company had previously furnished copies thereof to such Underwriter.

      (b) The Selling Stockholders will, severally and not jointly, indemnify
and hold harmless each Underwriter, its partners, members, directors and
officers and each person who controls such Underwriter within the meaning of
Section 15 of the Act, against any losses, claims, damages or liabilities, joint
or several, to which such Underwriter may become subject, under the Act or
otherwise, insofar as such losses, claims, damages or liabilities (or actions in
respect thereof) arise out of or are based upon any untrue statement or alleged
untrue statement of any material fact contained in any Registration Statement,
the Prospectus, or any amendment or supplement thereto, or any related
preliminary prospectus, or arise out of or are based upon the omission or
alleged omission to state therein a material fact required to be stated therein
or necessary to make the statements therein not misleading, and will reimburse
each Underwriter for any legal or other expenses reasonably incurred by such
Underwriter in connection with investigating or defending any such loss, claim,
damage, liability or action as such expenses are incurred; provided that the
Selling Stockholders shall only be subject to such liability to the extent that
the untrue statement or alleged untrue statement or omission or alleged omission
is based on written information provided by such Selling Stockholder or
contained in a representation or warranty given by such Selling Stockholder in
this Agreement or the Custody Agreement; provided, further, that the liability
under this Section of each Selling Stockholder shall be limited as described in
subsection (g) of this Section 7.

      (c) Each Underwriter will severally and not jointly indemnify and hold
harmless the Company, its directors and officers and each person, if any, who
controls the Company within the meaning of Section 15 of the Act, and each
Selling Stockholder against any losses, claims, damages or liabilities to which
the Company or such Selling Stockholder may become subject, under the Act or
otherwise, insofar as such losses, claims, damages or liabilities (or actions in
respect thereof) arise out of or are based upon any untrue statement or alleged
untrue statement of any material fact contained in any Registration Statement,
the Prospectus, or any amendment or supplement thereto, or any related
preliminary prospectus, or arise out of or are based upon the omission or the
alleged omission to state therein a material fact required to be stated therein
or necessary to make the statements therein not misleading, in each case to the
extent, but only to the extent, that such untrue statement or alleged untrue
statement or omission or alleged omission was made in reliance upon and in
conformity with written information furnished to the Company by such Underwriter
through the Representatives specifically for use therein, and will reimburse any
legal or other expenses reasonably incurred by the Company and each Selling
Stockholder in connection with investigating or defending any such loss, claim,
damage, liability


                                       30

or action as such expenses are incurred, it being understood and agreed that the
only such information furnished by any Underwriter consists of the following
information in the Prospectus furnished on behalf of each Underwriter: [to
come].

      (d) Promptly after receipt by an indemnified party under this Section or
Section 9 hereof of notice of the commencement of any action, such indemnified
party will, if a claim in respect thereof is to be made against an indemnifying
party under subsection (a), (b) or (c) above or Section 9 hereof, notify the
indemnifying party of the commencement thereof; provided that the failure to
notify the indemnifying party shall not relieve it from any liability that it
may have under subsection (a), (b) or (c) above or Section 9 hereof except to
the extent that it has been materially prejudiced (through the forfeiture of
substantive rights or defenses) by such failure; provided, further, that the
failure to notify the indemnifying party shall not relieve it from any liability
that it may have to an indemnified party otherwise than under subsection (a),
(b) or (c) above or Section 9 hereof. In case any such action is brought against
any indemnified party and it notifies an indemnifying party of the commencement
thereof, the indemnifying party will be entitled to participate therein and, to
the extent that it may wish, jointly with any other indemnifying party similarly
notified, to assume the defense thereof, with counsel reasonably satisfactory to
such indemnified party (who shall not, except with the consent of the
indemnified party, be counsel to the indemnifying party), and after notice from
the indemnifying party to such indemnified party of its election so to assume
the defense thereof, the indemnifying party will not be liable to such
indemnified party under this Section or Section 9 hereof, as the case may be,
for any legal or other expenses subsequently incurred by such indemnified party
in connection with the defense thereof other than reasonable costs of
investigation. No indemnifying party shall, without the prior written consent of
the indemnified party, effect any settlement of any pending or threatened action
in respect of which any indemnified party is or could have been a party and
indemnity could have been sought hereunder by such indemnified party unless such
settlement (i) includes an unconditional release of such indemnified party from
all liability on any claims that are the subject matter of such action and (ii)
does not include a statement as to, or an admission of, fault, culpability or a
failure to act by or on behalf of an indemnified party.

      (e) If the indemnification provided for in this Section is unavailable or
insufficient to hold harmless an indemnified party under subsection (a), (b) or
(c) above, then each indemnifying party shall contribute to the amount paid or
payable by such indemnified party as a result of the losses, claims, damages or
liabilities referred to in subsection (a), (b) or (c) above, (i) in such
proportion as is appropriate to reflect the relative benefits received by the
Company and the Selling Stockholders, on the one hand, and the Underwriters, on
the other, from the offering of the Securities 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


                                       31

fault of the Company and the Selling Stockholders, on the one hand, and the
Underwriters, on the other, in connection with the statements or omissions that
resulted in such losses, claims, damages or liabilities as well as any other
relevant equitable considerations. The relative benefits received by the Company
and the Selling Stockholders, on the one hand, and the Underwriters, on the
other, shall be deemed to be in the same proportion as the total net proceeds
from the offering (before deducting expenses) received by the Company and the
Selling Stockholders bear to the total underwriting discounts and commissions
received by the Underwriters. The relative fault shall be determined by
reference to, among other things, whether the untrue or alleged untrue statement
of a material fact or the omission or alleged omission to state a material fact
relates to information supplied by the Company, the Selling Stockholders or the
Underwriters and the parties' relative intent, knowledge, access to information
and opportunity to correct or prevent such untrue statement or omission. The
amount paid by an indemnified party as a result of the losses, claims, damages
or liabilities referred to in the first sentence of this subsection (e) shall be
deemed to include any legal or other expenses reasonably incurred by such
indemnified party in connection with investigating or defending any action or
claim which is the subject of this subsection (e). Notwithstanding the
provisions of this subsection (e), no Underwriter shall be required to
contribute any amount in excess of the underwriting discounts and commissions
applicable to the Offered Securities purchased by such Underwriter hereunder,
and no Selling Stockholder shall be required to contribute any amount in excess
of the amounts specified in subsection (g) of this Section 7. No person guilty
of fraudulent misrepresentation (within the meaning of Section 11(f) of the Act)
shall be entitled to contribution from any person who was not guilty of such
fraudulent misrepresentation. The Underwriters' obligations in this subsection
(e) to contribute are several in proportion to their respective underwriting
obligations and not joint.

      (f) The obligations of the Company and the Selling Stockholders under this
Section or Section 9 hereof shall be in addition to any liability which the
Company and the Selling Stockholders may otherwise have and shall extend, upon
the same terms and conditions, to each person, if any, who controls any
Underwriter or the QIU (as hereinafter defined) within the meaning of the Act.
The obligations of the Underwriters under this Section shall be in addition to
any liability which the respective Underwriters may otherwise have and shall
extend, upon the same terms and conditions, to each director of the Company, to
each officer of the Company who has signed a Registration Statement and to each
person, if any, who controls the Company within the meaning of the Act, to each
Selling Stockholder and to each person, if any, who controls any Selling
Stockholder within the meaning of the Act.

      (g) The liability of each Selling Stockholder under the representations,
warranties and agreements contained herein and under the indemnity and
contribution agreements contained in the provisions of this Section 7 shall be


                                       32

limited to an amount equal to the aggregate net proceeds received by such
Selling Stockholder (after deducting underwriting commissions and discounts, but
before expenses) from the sale of Offered Securities sold by such Selling
Stockholder hereunder.

      8. Default of Underwriters. If any Underwriter or Underwriters default in
their obligations to purchase Offered Securities hereunder on either the First
or any Optional Closing Date and the aggregate number of Offered Securities that
such defaulting Underwriter or Underwriters agreed but failed to purchase does
not exceed 10% of the total number of shares of Offered Securities that the
Underwriters are obligated to purchase on such Closing Date, the Representatives
may make arrangements satisfactory to the Company and the Selling Stockholders
for the purchase of such Offered Securities by other persons, including any of
the Underwriters, but if no such arrangements are made by such Closing Date, the
non-defaulting Underwriters shall be obligated severally, in proportion to their
respective commitments hereunder, to purchase the Offered Securities that such
defaulting Underwriters agreed but failed to purchase on such Closing Date. If
any Underwriter or Underwriters so default and the aggregate number of Offered
Securities with respect to which such default or defaults occur exceeds 10% of
the total number of Offered Securities that the Underwriters are obligated to
purchase on such Closing Date, and arrangements satisfactory to the
Representatives, the Company and the Selling Stockholders for the purchase of
such Offered Securities by other persons are not made within 36 hours after such
default, this Agreement will terminate without liability on the part of any
non-defaulting Underwriter, the Company or the Selling Stockholders, except as
provided in Section 10 hereof; provided that if such default occurs with respect
to Optional Securities after the First Closing Date, this Agreement will not
terminate as to the Firm Securities or any Optional Securities purchased prior
to such termination. As used in this Agreement, the term "Underwriter" includes
any person substituted for an Underwriter under this Section. Nothing herein
will relieve a defaulting Underwriter from liability for its default.

      9. Qualified Independent Underwriter. The Company hereby confirms that, at
its request, Thomas Weisel Partners LLC has, without compensation, acted as
"qualified independent underwriter" (in such capacity, the "QIU") within the
meaning of Rule 2710 of the Conduct Rules of the NASD in connection with the
offering of the Offered Securities. The Company and the Selling Stockholders
will severally and not jointly indemnify and hold harmless the QIU against any
losses, claims, damages or liabilities, joint or several, to which the QIU may
become subject under the Act or otherwise, insofar as such losses, claims,
damages or liabilities (or actions in respect thereof) arise out of or are based
upon the QIU's acting, or alleged failure to act, as such "qualified independent
underwriter" and will reimburse the QIU for any legal or other expenses
reasonably incurred by the QIU in connection with investigating or defending any
such loss, claim, damage, liability or action as such expenses are incurred;


                                       33

provided that the liability, if any, of each Selling Stockholder under this
Section shall be limited to the same extent as the liability, if any, of such
Selling Stockholder under Section 7(b) hereof.

      10. Survival of Certain Representations and Obligations. The respective
indemnities, agreements, representations, warranties and other statements of the
Selling Stockholders, of the Company or its officers and of the several
Underwriters set forth in or made pursuant to this Agreement will remain in full
force and effect, regardless of any investigation, or statement as to the
results thereof, made by or on behalf of any Underwriter, any Selling
Stockholder, the Company or any of their respective representatives, officers or
directors or any controlling person, and will survive delivery of and payment
for the Offered Securities. If this Agreement is terminated pursuant to Section
8 hereof or if for any reason the purchase of the Offered Securities by the
Underwriters is not consummated, the Company and the Selling Stockholders shall
remain responsible for the expenses to be paid or reimbursed by them pursuant to
Section 5 hereof and the respective obligations of the Company, the Selling
Stockholders, and the Underwriters pursuant to Section 7 hereof and the
obligations of the Company and the Selling Stockholders pursuant to Section 9
hereof shall remain in effect, and if any Offered Securities have been purchased
hereunder the representations and warranties in Section 2 hereof and all
obligations under Section 5 hereof shall also remain in effect. If the purchase
of the Offered Securities by the Underwriters is not consummated for any reason
other than solely because of the termination of this Agreement pursuant to
Section 8 hereof or the occurrence of any event specified in clauses (iii),
(iv), (vi), (vii), or (viii) of Section 6(c) hereof, the Company will reimburse
the Underwriters for all out-of-pocket expenses (including fees and
disbursements of counsel) reasonably incurred by them in connection with the
offering of the Offered Securities.

      11. Notices. All communications hereunder will be in writing and: (i) if
sent to the Underwriters, will be mailed, delivered or faxed and confirmed to
the Representatives, c/o Credit Suisse First Boston LLC, Eleven Madison Avenue,
New York, New York, 10010-3629, Attention: Transactions Advisory Group (fax:
212-325-4296), and J.P. Morgan Securities Inc., 277 Park Avenue, New York, New
York 10172, Attention: [Legal Department (fax: _____)]; (ii) if sent to the
Company, will be mailed, delivered or faxed and confirmed to it at MarketAxess
Holdings Inc., 140 Broadway, 42nd Floor, New York, New York 10005, Attention:
Mr. Charles R. Hood, General Counsel (fax: 212-813-6384); or (iii) if sent to
the Selling Stockholders or any of them, including the Over-Allotment Selling
Stockholders, will be mailed, delivered or faxed and confirmed to Richard M.
McVey, James N. B. Rucker and Charles R. Hood, as Attorneys-in-Fact for the
Selling Stockholders, c/o MarketAxess Holdings Inc., 140 Broadway, 42nd Floor,
New York, New York 10005 (fax: 212-813-6384); provided, however, that any notice
to an Underwriter pursuant to Section 7 hereof will be mailed, delivered or
faxed and confirmed to such Underwriter.


                                       34

      12. Successors. This Agreement will inure to the benefit of and be binding
upon the parties hereto and their respective personal representatives and
successors and the officers and directors and controlling persons referred to in
Section 7 hereof, and no other person will have any right or obligation
hereunder.

      13. Representation. The Representatives will act for the several
Underwriters in connection with the transactions contemplated by this Agreement,
and any action under this Agreement taken by the Representatives jointly will be
binding upon all the Underwriters. The Attorneys-in-Fact, as defined in the
Power of Attorney, will act for the Selling Stockholders in connection with such
transactions, and any action under or in respect of this Agreement taken by an
Attorney-in-Fact will be binding upon the Selling Stockholders.

      14. Counterparts. This Agreement may be executed in any number of
counterparts, each of which shall be deemed to be an original, but all such
counterparts shall together constitute one and the same Agreement.

      15. APPLICABLE LAW. THIS AGREEMENT SHALL BE GOVERNED BY, AND CONSTRUED IN
ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK, WITHOUT REGARD TO PRINCIPLES
OF CONFLICTS OF LAWS.

      The Company, the Selling Stockholders and the Underwriters hereby submit
to the non-exclusive jurisdiction of the Federal and state courts in the Borough
of Manhattan in The City of New York in any suit or proceeding arising out of or
relating to this Agreement or the transactions contemplated hereby.


                                       35

      If the foregoing is in accordance with the Representatives' understanding
of our agreement, kindly sign and return to the Company one of the counterparts
hereof, whereupon it will become a binding agreement among the Selling
Stockholders, the Company and the several Underwriters in accordance with its
terms.

                                    Very truly yours,

                                    MarketAxess Holdings Inc.

                                    By:
                                        ---------------------------------------
                                        Name:
                                        Title:



                                    Selling Stockholders

                                    By: Attorney-in-Fact

                                        Acting on behalf of the Selling
                                        Stockholders listed on Schedule I
                                        hereto.


                                        ---------------------------------------


                                       36

The foregoing Underwriting Agreement is hereby confirmed and accepted as of the
date first above written.

                                    Credit Suisse First Boston LLC
                                    J.P. Morgan Securities Inc.,

                                    Acting on behalf of themselves and as the
                                    Representatives of the several Underwriters
                                    listed on Schedule II hereto.

                                    Credit Suisse First Boston LLC

                                    By:
                                        ---------------------------------------
                                        Name:
                                        Title:


                                    J.P. Morgan Securities Inc.


                                    By:
                                        ---------------------------------------
                                        Name:
                                        Title:


                                       37