Document:

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                                                                     EXHIBIT 4.1

                                 [CERTIFICATE]

COMMON STOCK                   [MARKETAXESS LOGO]               COMMON STOCK

  NUMBER                                                           SHARES

   MA

                 MARKETAXESS HOLDINGS INC.                    CUSIP 57060D 10 8
    INCORPORATED UNDER THE LAWS OF THE STATE OF DELAWARE       SEE REVERSE FOR
                                                             CERTAIN DEFINITIONS

THIS CERTIFIES THAT

IS THE OWNER OF

       FULLY PAID AND NON-ASSESSABLE SHARES OF THE COMMON STOCK PAR VALUE
                               $0.003 PER SHARE OF

                           MARKETAXESS HOLDINGS INC.

transferable on the books of the Corporation by the holder hereof in person or
by duly authorized attorney upon surrender of this certificate properly
endorsed. This certificate is not valid unless countersigned and registered by
the Transfer Agent and Registrar.

         WITNESS the facsimile seal of the Corporation and the facsimile
signatures of its duly authorized officers.

Dated:

/s/ CHARLES HOOD                                   /s/ RICHARD M. McVEY
     SECRETARY             [SEAL]          PRESIDENT AND CHIEF EXECUTIVE OFFICER

                                COUNTERSIGNED AND REGISTERED:
                                                WACHOVIA BANK, N.A.
                                                 (Charlotte, N.C.)

                                                                  TRANSFER AGENT
                                                                   AND REGISTRAR

                                                BY
                                                            AUTHORIZED SIGNATURE

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                           MARKETAXESS HOLDINGS INC.

         The Corporation will furnish to any shareholder, upon request and
without charge, a full statement of the designations, relative rights,
preferences and limitations of the shares of each class and series of the shares
of capital stock of the Corporation authorized to be issued, so far as the same
have been determined, and of the authority of the Board to divide the shares
into classes or series and to determine and change the relative rights,
preferences and limitations of any class or series. Such request may be made to
the office of the Secretary of the Corporation or to the Transfer Agent named on
the face of this Certificate.

         The following abbreviations, when used in the inscription on the face
of this certificate, shall be construed as though they were written out in full
according to applicable laws or regulations:

TEN COM  -   as tenants in common
TEN ENT  -   as tenants by the entireties
JT TEN   -   as joint tenants with right
             of survivorship and not as
             tenants in common

                    UNIF GIFT MIN ACT - ...............Custodian ...............
                                           (Cust)                   (Minor)

                                       under Uniform Gifts to Minors

                                       Act......................................
                                                         (State)

                    UNIF TRF MIN ACT - ...........Custodian (until age ........)
                                         (Cust)

                                       ..................under Uniform Transfers
                                            (Minor)

                                       to Minors Act...........................
                                                               (State)

    Additional abbreviations may also be used though not in the above list.

FOR VALUE RECEIVED, ______________________ hereby sell, assign and transfer unto

PLEASE INSERT SOCIAL SECURITY OR OTHER
    IDENTIFYING NUMBER OF ASSIGNEE

[                                     ]

________________________________________________________________________________
 (PLEASE PRINT OR TYPEWRITE NAME AND ADDRESS, INCLUDING ZIP CODE, OF ASSIGNEE)

________________________________________________________________________________

________________________________________________________________________________

_________________________________________________________________________ Shares
of the common stock represented by the within Certificate, and do hereby
irrevocably constitute and appoint

_______________________________________________________________________ Attorney
to transfer the said stock on the books of the within named Corporation
with full power of substitution in the premises.

Dated _____________________

                                  X ____________________________________________

                                  X ____________________________________________

                            NOTICE: THE SIGNATURE(S) TO THIS ASSIGNMENT MUST
                                    CORRESPOND WITH THE NAME(S) AS WRITTEN UPON
                                    THE FACE OF THE CERTIFICATE IN EVERY
                                    PARTICULAR, WITHOUT ALTERATION OR
                                    ENLARGEMENT OR ANY CHANGE WHATEVER.

Signature(s) Guaranteed

By ________________________________________
THE SIGNATURE(S) SHOULD BE GUARANTEED BY AN
ELIGIBLE GUARANTOR INSTITUTION (BANKS,
STOCKBROKERS, SAVINGS AND LOAN ASSOCIATIONS
AND CREDIT UNIONS WITH MEMBERSHIP IN AN
APPROVED SIGNATURE GUARANTEE MEDALLION
PROGRAM), PURSUANT TO S.E.C. RULE 17Ad-15.

PLEASE KEEP THIS CERTIFICATE IN A SAFE PLACE. IF IT IS LOST, STOLEN, MUTILATED
OR DESTROYED, THE CORPORATION MAY REQUIRE A BOND OF INDEMNITY AS A CONDITION TO
THE ISSUANCE OF A REPLACEMENT CERTIFICATE.<PAGE>

                                                                     EXHIBIT 4.3

THE WARRANT REPRESENTED HEREBY AND THE COMMON STOCK OR OTHER SECURITIES ISSUABLE
UPON THE EXERCISE HEREOF HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF
1933, AS AMENDED (THE "ACT"), OR ANY STATE SECURITIES LAWS AND NEITHER THIS
WARRANT NOR THE COMMON STOCK OR OTHER SECURITIES ISSUABLE UPON THE EXERCISE
HEREOF NOR ANY INTEREST THEREIN MAY BE TRANSFERRED IN THE ABSENCE OF SUCH
REGISTRATION OR AN EXEMPTION THEREFROM UNDER SUCH ACT AND SUCH LAWS AND THE
RULES AND REGULATIONS THEREUNDER.

                        WARRANT TO PURCHASE COMMON STOCK
                                       OF
                            MARKETAXESS HOLDINGS INC.

Warrant No.:                                         Dated: [        ],

                  This certifies that [_____________________], a Delaware
corporation (the "Holder"), for value received, is entitled to purchase from
MarketAxess Holdings Inc., a Delaware corporation (the "Company"), up to an
aggregate of [__________________] ([_________]) fully paid and nonassessable
shares of common stock of the Company, par value $0.003 per share (the "Stock"),
at a price of $0.003 per share (the "Stock Purchase Price"), at any time or from
time to time in accordance with the terms and conditions of this Warrant, but
not later than 5:00 p.m. (New York time) on November 30, 2008 (the "Expiration
Date"). The Stock Purchase Price and the number of shares purchasable hereunder
(wherever expressed herein as a particular number) are subject to adjustment as
provided in Section 4 of this Warrant. This warrant (this "Warrant") is one of a
series of similar warrants being issued pursuant to the Amended and Restated
Warrant (the "Master Warrant"), dated as of April 4, 2002, issued to Bear Market
Axess Corp., Credit Suisse First Boston Next Fund, Inc., DB Capital, Inc., J.P.
Morgan Partners (23A SBIC), LLC, LabMorgan Corporation, LB I Group Inc., and
Banc of America Technology Investments, Inc. (collectively the "Participating
Dealers"). The Holder acknowledges that, upon receipt of this Warrant, it is no
longer a party to and has no further rights under the Master Warrant. The number
of shares of Stock and the Stock Purchase Price have been adjusted to reflect
the 10-for-1 stock split effective June 28, 2001 and the 1-for-3 reverse stock
split effective [_________], 2004.

                  This Warrant is subject to the following terms and conditions:

                  1.       Exercise. This Warrant is exercisable at the option
of the Holder at any time or from time to time on or after the date hereof but
not later than the Expiration Date, for all or a portion of the shares of Stock
which the Holder is entitled to purchase hereunder, by

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delivery to the Company of an exercise notice in the form of Exhibit A hereto
(an "Exercise Notice").

                  2.       Payment; Certificates; Issuance of Stock.

                           2.1      Payment. The purchase rights under this
Warrant may be exercised by the Holder, in whole or in part, by surrender of
this Warrant at the principal office of the Company and by the payment to the
Company by certified check or wire transfer in an amount equal to the aggregate
purchase price of the shares being purchased.

                           2.2      Net Issue Exercise. In lieu of exercising
this Warrant pursuant to Section 2.1, the Holder may elect to receive shares of
Stock equal to the value of the portion of this Warrant being exercised by
surrender of this Warrant at the principal office of the Company together with
notice of such election, in which event the Company shall issue to the Holder a
number of shares of Stock computed using the following formula:

                                   X = Y (A-B)
                                       -------
                                          A

         Where:

         X =      the number of shares of Stock to be issued to the Holder

         Y =      the number of shares of Stock as to which this Warrant is to
be deemed to have been exercised;

         A =      the fair market value of one share of the Company's common
stock (at the date of such calculation); and

         B =      Stock Purchase Price (as adjusted to the date of such
calculation).

                           2.3      Fair Market Value. For purposes of this
Section 2, the "fair market value" of one share of the Company's common stock
shall be determined as follows:

                                    2.3.1    If the common stock is traded in
the over-the-counter market or on an exchange, the fair market value of the
common stock per share shall be the average of the closing bid and asked prices
of the common stock in the over-the-counter market or the closing sale price
quoted on any exchange on which the common stock is listed as published in The
Wall Street Journal, in each case for the ten (10) trading days prior to the
date of determination of fair market value.

                                    2.3.2    If the common stock is not traded
in the over-the-counter market or on an exchange, the fair market value of the
common stock per share shall be the price per share which the Company could
obtain from a willing buyer for shares sold by the Company from authorized but
unissued shares, as determined by the Company's Board of Directors.

                           2.4      Certificates, Etc. Upon any exercise of this
Warrant, the Company shall issue and deliver to the Holder, shares of Stock as
provided herein. The Company agrees that the shares of Stock to be purchased
under this Warrant shall be and are deemed to be issued to the Holder as the
record owner of such shares as of the close of business on the date on which

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this Warrant shall have been surrendered and payment made for such shares on the
terms and conditions provided herein. Subject to the provisions of Sections 3
and 8, certificates for shares of Stock so purchased, together with any other
securities or property to which the Holder is entitled upon such exercise, shall
be delivered to the Holder by the Company or the Company's transfer agent at the
Company's expense within a reasonable time (but in no event more than ten days)
after rights represented by this Warrant have been exercised. Each stock
certificate so delivered shall be in such denominations of Stock as may be
requested by the Holder and shall be registered in the name of the Holder or
such other name as shall be designated by the Holder, subject to the limitations
contained in Sections 3, 7 and 8. If, upon exercise of this Warrant, fewer than
all of the shares of Stock evidenced by this Warrant are purchased prior to the
Expiration Date, one or more new warrants substantially in the form of, and on
the terms in, this Warrant will be issued for the remaining number of shares of
Stock and the provisions hereof will be modified to reflect the prior
exercise(s) hereof.

                  3.       Shares to be Fully Paid; Reservation of Shares. The
Company covenants and agrees that all shares of Stock which may be issued upon
the exercise of the rights represented by this Warrant will be, upon payment of
the Stock Purchase Price therefor and issuance thereof, duly authorized, validly
issued, fully paid and nonassessable and free from all preemptive rights of any
stockholder and free of all taxes, liens and charges with respect to the issue
thereof. The Company further covenants and agrees that during the period within
which the rights represented by this Warrant may be exercised, the Company will
at all times have authorized and reserved, for the purpose of issue or transfer
upon exercise of the subscription rights evidenced by this Warrant, a sufficient
number of shares of authorized but unissued Stock for such exercise. The Company
will take all such action as may be necessary to assure that such shares of
Stock may be issued as provided herein without violation of any applicable law
or regulation, or of any requirements of any securities exchange or automated
quotation system upon which the Stock may be listed.

                  4.       Adjustment of Stock Purchase Price and Number of
Shares. The Stock Purchase Price and the number of shares purchasable upon the
exercise of this Warrant shall be subject to adjustment from time to time upon
the occurrence of certain events described in this Section 4.

                           4.1      Subdivision or Combination of Stock. In case
the Company shall at any time subdivide its outstanding shares of Stock into a
greater number of shares, the Stock Purchase Price in effect immediately prior
to such subdivision shall be proportionately reduced, and the number of shares
issuable upon exercise of this Warrant shall be proportionately increased.
Conversely, in case the outstanding shares of Stock of the Company shall be
combined into a smaller number of shares, the Stock Purchase Price in effect
immediately prior to such combination shall be proportionately increased and the
number of shares issuable upon exercise of this Warrant shall be proportionately
reduced.

                           4.2      Certain Dividends and Distributions. In case
the Company shall at any time declare or pay a dividend upon its Stock payable
in shares of Stock, the Stock Purchase Price in effect immediately prior to such
dividend shall be proportionately reduced and the number of shares issuable upon
exercise of this Warrant shall be proportionately increased. In

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case the Company shall at any time declare or pay a dividend or other
distribution on its Stock payable in cash or in evidences of indebtedness,
shares of stock or other securities or property (other than Stock) or in rights,
warrants or options to subscribe for or purchase evidences of indebtedness,
shares of stock or other securities or property, the Holder shall be entitled to
receive such dividends or distributions as if this Warrant had been exercised in
full for cash (assuming all shares of Stock purchasable hereunder had fully
vested). Such dividends or distributions to the Holder shall be held by the
Company for the benefit of the Holder, and made to the Holder with respect to
any and all shares of Stock that the Holder is entitled to purchase hereunder,
immediately upon such shares of Stock becoming purchasable hereunder.

                           4.3      Notice of Adjustment. Upon any adjustment of
the Stock Purchase Price or any increase or decrease in the number of shares
purchasable upon the exercise of this Warrant, the Company shall give written
notice thereof, by first class mail, postage prepaid, addressed to the
registered holder of this Warrant at the address of such holder listed on the
signature page hereto. The notice shall be signed by the Company's chief
executive officer and shall state the effective date of the adjustment and the
Stock Purchase Price resulting from such adjustment and the increase or
decrease, if any, in the number of shares purchasable at such price upon the
exercise of this Warrant, setting forth in reasonable detail the method of
calculation and the facts upon which such calculation is based.

                           4.4      Other Notices. If at any time:

                           (a)      the Company shall propose to declare any
cash dividend upon its Stock;

                           (b)      the Company shall propose to declare or make
any dividend or other distribution to the holders of its Stock, whether in cash,
property or other securities;

                           (c)      the Company shall propose to effect any
reorganization or reclassification of the capital stock of the Company or any
consolidation or merger of the Company with or into another corporation in which
the holders of Common Stock would receive any consideration for their shares of
Common Stock, or any sale, lease or conveyance of all or substantially all of
the assets of the Company; or

                           (d)      the Company shall propose to effect a
voluntary or involuntary dissolution, liquidation or winding-up of the Company;

then, in any one or more of said cases, the Company shall give, by certified or
registered mail, postage prepaid, addressed to the Holder at the address of the
Holder listed on the signature page hereto, (i) at least 15 business days' prior
written notice of the date on which the books of the Company shall close or a
record shall be taken for such dividend or distribution or for determining
rights to vote in respect of any such reorganization, reclassification,
consolidation, merger, sale, lease, conveyance, dissolution, liquidation or
winding-up, and (ii) in the case of any such reorganization, reclassification,
consolidation, merger, sale, lease, conveyance, dissolution, liquidation or
winding-up, at least 30 days' written notice of the date when the same shall
take place. Upon the occurrence of an event described in clause (c), the Holder
shall be entitled

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thereafter to receive upon exercise of this Warrant, as and when exercised, the
kind and amount of shares of stock or other securities or assets which the
Holder would have been entitled to receive after the occurrence of such event
had this Warrant been exercised in full immediately prior to such event
(assuming the entire amount of this Warrant was fully exercisable at such time);
and in any such case, appropriate provision shall be made with respect to the
rights and interests of the Holder to the end that the provisions of this
Warrant (including, without limitation, provisions with respect to changes in
and adjustments of the Stock Purchase Price and the number of shares purchasable
upon the exercise of this Warrant) shall thereafter be applicable, as nearly as
may be, in relation to any shares of stock, or other securities or assets,
thereafter deliverable upon the exercise of this Warrant. The Company will not
effect any of the transactions described in clause (c) above unless, prior to
the consummation thereof, each person (other than the Company) that may be
required to deliver any cash, stock, securities or other assets upon the
exercise of this Warrant as provided herein shall assume, by written instrument
delivered to, and reasonably satisfactory to, the Holder, (x) the obligations of
the Company under this Warrant (and if the Company shall survive the
consummation of any such transaction, such assumption shall be in addition to,
and shall not release the Company from, any continuing obligations of the
Company under this Warrant) and (y) the obligation to deliver to the Holder such
cash, stock, securities or other assets as such holder may be entitled to
receive in accordance with the provisions of this Section 4. The provisions of
this Section 4.4 shall similarly apply to successive transactions.

                  5.       Issue Tax. The issuance of certificates for shares of
Stock upon the exercise of this Warrant shall be made without charge to the
Holder for any issue tax in respect thereof; provided, however, that the Company
shall not be required to pay any tax which may be payable in respect of any
transfer involved in the issuance and delivery of any certificate in a name
other than that of the then Holder of the Warrant being exercised.

                  6.       No Voting Rights; Limitation of Liability. Nothing
contained in this Warrant shall be construed as conferring upon the Holder the
right to vote or to consent or to receive notice as a stockholder in respect of
meetings of stockholders for the election of directors of the Company or any
other matters or any rights whatsoever as a stockholder of the Company. No
provisions hereof, in the absence of affirmative action by the Holder to
purchase shares of Stock, and no mere enumeration herein of the rights or
privileges of the Holder, shall give rise to any liability of the Holder for the
Stock Purchase Price or as a stockholder of the Company whether such liability
is asserted by the Company or by its creditors.

                  7.       Restrictions on Transferability; Compliance With
Securities Act.

                           7.1      Restrictions on Transferability. This
Warrant and the Stock issued hereunder (collectively, the "Securities"), shall
not be transferable in the absence of registration under the Act or an exemption
therefrom. If the Holder is an entity that was formed for the sole purpose of
holding Securities or that has no substantial assets other than the Securities
or other shares of capital stock of the Company agrees that (a) shares of its
capital stock or other instruments, certificates or documents reflecting equity
interests in such entity (and the shares of capital stock or other equity
interests in any similar entities controlling such entity) will note the
restrictions contained in this Warrant on the transfer of securities as if such
common stock or

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other equity interests were Securities or other shares of capital stock of the
Company, as applicable, and (b) no shares of such capital stock or other equity
interests may be transferred to any person or entity other than in accordance
with the terms and provisions of this Warrant as if such capital stock or other
equity interests were Securities.

                           7.2      Restrictive Legend. Each certificate
representing the Securities or any other securities issued in respect of the
Securities upon any stock split, stock dividend, recapitalization, merger,
consolidation or similar event, or any other interests or securities restricted
hereby, shall be stamped or otherwise imprinted with a legend substantially in
the following form (in addition to any legend required under applicable state
securities laws), unless counsel shall advise the Company that such legend is no
longer required:

                  THE SECURITIES REPRESENTED HEREBY HAVE NOT BEEN REGISTERED
UNDER THE SECURITIES ACT OF 1933, AS AMENDED ("ACT"), OR ANY STATE SECURITIES
LAWS AND NEITHER SUCH SECURITIES NOR ANY INTEREST THEREIN MAY BE TRANSFERRED IN
THE ABSENCE OF SUCH REGISTRATION OR AN EXEMPTION THEREFROM UNDER SUCH ACT AND
SUCH LAWS AND THE RULES AND REGULATIONS THEREUNDER.

                           7.3      Effect of Transfer. Subject to the
provisions of Section 7.1 hereof and any other agreement relating to the
transfer of this Warrant or Warrant Shares, the Holder may transfer all or any
portion of this Warrant by surrendering this Warrant to the Company together
with a completed assignment in the form attached hereto as Exhibit B. Upon such
surrender, the Company shall deliver a new Warrant or Warrants to the person or
persons entitled thereto and, if applicable, shall deliver to the Holder a new
Warrant evidencing the right of the Holder to purchase the balance of the shares
of Stock subject to purchase hereunder. The term "Holder" as used herein shall
include any transferee to whom this Warrant has been transferred in accordance
with this Section 7.3.

                  8.       Limitation on Exercise. Notwithstanding anything to
the contrary contained herein, the number of shares of Common Stock that may be
acquired by the Holder upon any exercise of this Warrant (or otherwise in
respect hereof) shall be limited to the extent necessary to insure that,
following such exercise (or other issuance), the total number of shares of
Common Stock then beneficially owned by the Holder and its Affiliates and any
other persons whose beneficial ownership of Common Stock would be aggregated
with the Holder's for purposes of Section 13(d) of the Securities Exchange Act
of 1934, as amended (the "Exchange Act"), does not exceed 9.99% (the "Maximum
Percentage") of the total number of issued and outstanding shares of Common
Stock (including for such purpose the shares of Common Stock issuable upon such
exercise). For such purposes, beneficial ownership shall be determined in
accordance with Section 13(d) of the Exchange Act and the rules and regulations
promulgated thereunder. Each delivery of an Exercise Notice by the Holder will
constitute a representation by the Holder that it has evaluated the limitation
set forth in this paragraph and determined that issuance of the full number of
shares of Common Stock requested in such Exercise Notice is permitted under this
paragraph. Upon the written request of the Holder, the Corporation shall
promptly confirm in writing to any such holder the number of shares of Common
Stock then outstanding.

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<PAGE>

                  9.       Registration Rights. The shares of Stock purchasable
hereunder constitute "Registrable Investor Securities" as defined in the Sixth
Amended and Restated Registration Rights Agreement, dated as of April 4, 2002,
by and among the Company, the Holder and the other parties thereto, and shall be
entitled to registration rights in accordance with such Agreement.

                  10.      Modification and Waiver. This Warrant and any
provision hereof may be amended, changed, waived, discharged or terminated only
by an instrument in writing signed by the Company and Participating Dealers
holding a majority of the shares of Stock issuable upon exercise of the warrants
issued under the Master Warrant, assuming that all such warrants are exercised
for cash (and not on a cashless basis).

                  11.      Notices. Any notice, request or other document
required or permitted to be given or delivered to the Holder or the Company
shall be personally delivered or shall be sent by certified or registered mail,
postage prepaid, to Holder at its address listed on the signature page hereto or
to the Company at the address indicated therefor in the first paragraph of this
Warrant. Any notice given by personal delivery shall be deemed given upon
receipt, and any notice given by certified or registered mail shall be deemed
given five days after registration or certification thereof, as the case may be.

                  12.      Descriptive Headings, Governing Law and Jurisdiction.
The descriptive headings of the several sections and paragraphs of this Warrant
are inserted for convenience only and do not constitute a part of this Warrant.
This Warrant shall be construed and enforced in accordance with, and the rights
of the parties shall be governed by, the laws of the State of New York as
applied to agreements among New York residents entered into and to be performed
entirely within New York. Any judicial proceeding involving any dispute,
controversy or claim arising out of or relating to this Warrant may be brought
in a court located in the County, City and State of New York, and each of the
Company and the Holder (i) unconditionally accepts the non-exclusive
jurisdiction of such courts and any related appellate court and irrevocably
agrees to be bound by any judgment rendered thereby, (ii) irrevocably waives any
objection it may now or hereafter have as to the venue of any such proceeding
brought in such a court or that such a court is an inconvenient forum and (iii)
waives personal service of any and all process upon it, and consents that all
such service of process be made by registered or certified mail, return receipt
requested, directed to it at its address listed on the signature page hereto.
Each of the Company and the Holder hereby waives trial by jury in any judicial
proceeding to which it is a party.

                  13.      Lost Warrants or Stock Certificates. The Company
represents and warrants to, and agrees with, the Holder that upon receipt of
evidence reasonably satisfactory to the Company of the loss, theft, destruction,
or mutilation of any Warrant or stock certificate and, in the case of any such
loss, theft or destruction, upon receipt of an indemnity, or in the case of any
such mutilation, upon surrender and cancellation of such Warrant or stock
certificate, the Company at its expense will make and deliver a new Warrant or
stock certificate, of like tenor, in lieu of the lost, stolen, destroyed or
mutilated Warrant or stock certificate.

                                       7
<PAGE>

                  14.      Fractional Shares. No fractional shares shall be
issued upon exercise of this Warrant. The Company shall, in lieu of issuing any
fractional share and notwithstanding anything to the contrary contained herein,
round up the number of shares issuable to the Holder upon any exercise hereof to
the next whole number.

                  15.      Counterpart Signatures. This Warrant may be executed
in any number of counterparts, each of which shall be deemed to be an original,
and all of which together shall constitute one and the same document. This
Warrant may be executed by facsimile signatures.

                     [END OF TEXT. SIGNATURE PAGE FOLLOWS.]

                                       8
<PAGE>

                  IN WITNESS WHEREOF, the Company has caused this Warrant to be
executed by a duly authorized officer as of the date first indicated above.

                                       MARKETAXESS HOLDINGS INC.

                                       By: __________________________________
                                           Richard M. McVey
                                           Chief Executive Officer

ACCEPTED:

[HOLDER]

                                           Address:

By: ___________________________
    Name:                                  Telecopy:
    Title:                                 Attn:

<PAGE>

                                                                       EXHIBIT A

                             FORM OF EXERCISE NOTICE

(To be signed only upon exercise of Warrant)

To: ___________________________

                  The undersigned, the holder of the within Warrant, hereby
irrevocably elects to exercise the purchase right represented by such Warrant
for, and to purchase thereunder, _________________________ (___________) shares
of common stock of MarketAxess Holdings Inc. (the "Company") and herewith [makes
payment of ______________________________________ Dollars ($______________)
therefor [by wire transfer] [by delivery of the enclosed certified
check]][elects to exercise this Warrant with respect to ___________ shares of
Stock pursuant to the Net Issue Exercise provisions of Section 2.2 thereof] and
requests that the certificates for such shares be issued in the name of, and
delivered to, _________________________________________________________________,
whose address is ______________________________________________________________.

DATED: _______________

(Signature must conform in all respects to name
of holder as specified on the face of the Warrant)

                                                    (Address)

<PAGE>

                                                                       EXHIBIT B

                               FORM OF ASSIGNMENT

(To be executed by the registered Holder if such Holder desires to transfer the
attached Warrant.)

                  FOR VALUE RECEIVED, ____________________________ hereby sells,
assigns, and transfers unto ___________________________ a Warrant to purchase
____________ shares of common stock of MarketAxess Holdings Inc. (the
"Company"), together with all right, title, and interest therein, and does
hereby irrevocably constitute and appoint ___________ attorney to transfer such
Warrant on the books of the Company, with full power of substitution.

Dated: ________________________

                                               Signature _______________________

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