Document:

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                                                                     Exhibit 4.4

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                          REGISTRATION RIGHTS AGREEMENT

                                      among

                          OPTIMARK TECHNOLOGIES, INC.,

                       GENERAL ATLANTIC PARTNERS 35, L.P.,

                        GAP COINVESTMENT PARTNERS, L.P.,

                           DOW JONES & COMPANY, INC.,

                                 ALICE L. WALTON

                                       and

                     THE PACIFIC STOCK EXCHANGE INCORPORATED

                        ---------------------------------
                             Dated: August 27, 1996
                        ---------------------------------

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                                TABLE OF CONTENTS

                                                                            Page

1. Definitions ............................................................   1

2. General; Securities Subject to this Agreement ..........................   5
   (a) Grant of Rights ....................................................   5
   (b) Registrable Securities .............................................   5
   (c) Holders of Registrable Securities ..................................   5

3. Demand Registration ....................................................   5
   (a) Request for Demand Registration ....................................   5
   (b) Effective Demand Registration ......................................   6
   (c) Expenses ...........................................................   6
   (d) Underwriting Procedures ............................................   7
   (e) Selection of Underwriters ..........................................   7

4. Piggy-Back Registration ................................................   7
   (a) Piggy-Back Rights ..................................................   7
   (b) Expenses ...........................................................   8

5. Holdback Agreements ....................................................   8
   (a) Restrictions on Public Sale by Designated Holders ..................   8
   (b) Restrictions on Public Sale by the Company .........................   8

6. Registration Procedures ................................................   9
   (a) Obligations of the  Company ........................................   9
   (b) Seller Information .................................................  12
   (c) Notice to Discontinue ..............................................  12
   (d) Registration Expenses ..............................................  12

7. Indemnification; Contribution ..........................................  13
   (a) Indemnification by the Company .....................................  13
   (b) Indemnification by Designated Holders ..............................  13
   (c) Conduct of Indemnification Proceedings .............................  14
   (d) Contribution .......................................................  14

8. Rule 144 ...............................................................  15

9. Miscellaneous ..........................................................  15
   (a) Recapitalizations, Exchanges, etc ..................................  15
   (b) No Inconsistent Agreements .........................................  16

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                                                                            Page

(c) Remedies ..............................................................  16
(d) Amendments and Waivers ................................................  16
(e) Notices ...............................................................  16
(f) Successors and Assigns; Third Party Beneficiaries .....................  18
(g) Counterparts ..........................................................  19
(h) Headings ..............................................................  19
(i) GOVERNING LAW .........................................................  19
(j) Severability ..........................................................  19
(k) Entire Agreement ......................................................  19
(1) Further Assurances ....................................................  19

                                       ii
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                          REGISTRATION RIGHTS AGREEMENT

            REGISTRATION RIGHTS AGREEMENT, dated August 27, 1996 (this
"Agreement"), among OptiMark Technologies, Inc., a Delaware corporation (the
"Company"), General Atlantic Partners 35, L.P., a Delaware limited Partnership
("GAP LP"), GAP Coinvestment Partners, L.P., a New York limited partnership
("GAP Coinvestment"), Dow Jones & Company, Inc., a Delaware corporation
("Dow Jones"), Alice L. Walton ("Walton") and The Pacific Stock Exchange
Incorporated, a Delaware corporation ("PSE").

            This Agreement is made in connection with the Stock Purchase
Agreement, dated the date hereof (the "Stock Purchase Agreement"), among the
Company, GAP LP, GAP Coinvestment, Dow Jones and Walton, pursuant to which the
Company has agreed to issue and sell to (a) GAP LP, and GAP LP has agreed to
purchase from the Company, 1,162,753 shares, par value $.Ol per share, of Series
A Convertible Participating Preferred Stock of the Company (the "Preferred
Stock"), (b) GAP Coinvestment, and GAP Coinvestment has agreed to purchase from
the Company, 201,504 shares of Preferred Stock, (c) Dow Jones, and Dow Jones has
agreed to purchase from the Company, 682,129 shares of Preferred Stock and (d)
Walton, and Walton has agreed to purchase from the Company, 136,426 shares of
Preferred Stock. Each share of Preferred Stock is convertible into one (1)
share, par value $.O1 per share, of Common Stock of the Company (the "Common
Stock"), subject to adjustments. On the date hereof, PSE has the right to
purchase up to 526,000 shares of Common Stock pursuant to a Common Stock
Purchase Warrant, dated the date hereof, issued by the Company to PSE (the "PSE
Warrant"). In order to induce (i) GAP LP, GAP Coinvestment, Dow Jones and Walton
to enter into the Stockholders Agreement, dated the date hereof (the
"Stockholders Agreement") and (ii) PSE to enter into the PSE-OptiMark Agreement,
dated the date hereof, between the Company and PSE, and for other good and
valuable consideration, the receipt and adequacy of which is hereby
acknowledged, the Company has agreed to grant registration rights with respect
to the Registrable Securities (as hereinafter defined) as set forth in this
Agreement.

            The parties hereby agree as follows:

            1. Definitions. As used in this Agreement the following terms have
the meanings indicated:

               "Act" means the Securities Act of 1933, as amended.

               "Affiliate" shall mean any Person who is an "affiliate" as
defined in Rule 12b-2 of the General Rules and Regulations under the Exchange
Act. In addition, the following shall be deemed to be Affiliates of GAP LP: (a)
GAP LLC, the members of GAP LLC, and the limited partners of GAP LP; (b) any
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Affiliate of GAP LLC, the members of GAP LLC and the limited partners of GAP LP;
and (c) any limited liability company or partnership a majority of whose members
or partners, as the case may be, are members, former members, consultants or key
employees of GAP LLC. In addition, GAP LP and GAP Coinvestment shall be deemed
to be Affiliates of one another.

               "Approved Underwriter" has the meaning assigned such term in
Section 3(e).

               "Common Stock" means the Common Stock, par value $.Ol per share,
of the Company or any other equity securities of the Company into which such
securities are converted, reclassified, reconstituted or exchanged.

               "Company" has the meaning assigned to such term in the recital to
this Agreement.

               "Company Underwriter" has the meaning assigned such term in
Section 4(a).

               "Demand Registration" has the meaning assigned such term in
Section 3(a).

               "Designated Holder" means each of the General Atlantic
Stockholders, the Dow Jones Stockholders, the Walton Stockholders and the PSE
Stockholders and any transferee of any of them to whom Registrable Securities
have been transferred in accordance with the provisions of this Agreement, other
than a transferee to whom such securities have been transferred pursuant to a
registration statement under the Securities Act or Rule 144 or Regulation S
under the Securities Act.

               "Dow Jones" has the meaning assigned such term in the recital to
this Agreement.

               "Dow Jones Stockholders" means Dow Jones and any Affiliate
thereof to which Registrable Securities are transferred.

               "Exchange Act" means the Securities Exchange Act of 1934, as
amended, and the rules and regulations promulgated thereunder.

               "GAP LLC" means General Atlantic Partners, LLC, a Delaware
limited liability company and the general partner of GAP LP, and any successor
to such entity.

               "GAP Coinvestment" has the meaning assigned such term in the
recital to this Agreement.
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                                                                               3

               "GAP LP" has the meaning assigned such term in the recital to
this Agreement.

               "General Atlantic Stockholders" means GAP LP, GAP Coinvestment
and any Affiliate thereof to which Registrable Securities are transferred.

               "Holders' Counsel" has the meaning assigned such term in Section
6(a)(i).

               "Indemnified Party" has the meaning assigned such term in Section
7(c).

               "Indemnifying Party" has the meaning assigned such term in
Section 7(c).

               "Initiating Holders" has the meaning assigned such term in
Section 3(a).

               "Inspector" has the meaning assigned such term in Section 6(a)
(viii).

               "IPO Effectiveness Date" means the date upon which the Company
commences its initial offer for sale of shares of Common Stock pursuant to an
effective Registration Statement filed under the Securities Act.

               "NASD" has the meaning assigned such term in Section 6(a)(xiii).

               "Person" means any individual, firm, corporation, partnership,
limited liability company, trust, incorporated or unincorporated association,
joint venture, joint stock company, limited liability company, government (or an
agency or political subdivision thereof) or other entity of any kind, and shall
include any successor (by merger or otherwise) of such entity.

               "Preferred Stock" has the meaning assigned to such term in the
recital to this Agreement.

               "PSE" means The Pacific Stock Exchange Incorporated.

               "PSE Stockholders" means PSE and any Affiliate thereof to which
Registrable Securities are transferred.

               "PSE Warrant" means the Common Stock Purchase Warrant, dated the
date hereof, issued by the Company in favor of PSE.
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               "Records" has the meaning assigned such term in Section 6(a)(v
iii).

               "Registrable Securities" means each of the following: (a) any and
all shares of Common Stock owned by the Designated Holders and issued or
issuable upon conversion of shares of Preferred Stock, (b) any other shares of
Common Stock acquired or owned by any of the Designated Holders prior to the IPO
Effectiveness Date, or acquired or owned by any of the Designated Holders after
the IPO Effectiveness Date, if such Designated Holder is an Affiliate of the
Company, (c) any shares of Common Stock issued or issuable to any of the
Designated Holders with respect to shares of Common Stock or shares of Preferred
Stock by way of stock dividend or stock split or in connection with a
combination of shares, recapitalization, merger, consolidation or other
reorganization or otherwise and shares of Common Stock issuable upon conversion,
exercise or exchange thereof and (d) to the extent exercisable at the time such
amount of Registrable Securities is to be determined, any and all shares of
Common Stock issuable to PSE upon exercise of the PSE Warrant.

               "Registration Expenses" has the meaning set forth in Section
6(d).

               "Registration Statement" means a registration statement filed
pursuant to the Securities Act.

               "SEC" means the Securities and Exchange Commission or any similar
agency then having jurisdiction to enforce the Securities Act.

               "Securities Act" means the Securities Act of 1933, as amended,
and the rules and regulations promulgated thereunder.

               "Stock Purchase Agreement" has the meaning assigned such term in
the recital to this Agreement.

               "Stockholders Agreement" has the meaning assigned such term in
the recital to this Agreement.

               "Walton" has the meaning assigned such term in the recital to
this Agreement.

               "Walton Stockholders" means Walton and any Permitted Transferee
(as defined in the Stockholders Agreement) thereof to which Registrable
Securities are transferred.
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                                                                               5

            2. General; Securities Subject to this Agreement.

               (a) Grant of Rights. The Company hereby grants registration
rights to the General Atlantic Stockholders, the Dow Jones Stockholders, the
Walton Stockholders and the PSE Stockholders upon the terms and conditions set
forth in this Agreement.

               (b) Registrable Securities. For the purposes of this Agreement,
Registrable Securities will cease to be Registrable Securities when (i) a
registration statement covering such Registrable Securities has been declared
effective under the Securities Act by the SEC and such Registrable Securities
have been disposed of pursuant to such effective registration statement, (ii)
the entire amount of such Registrable Securities proposed to be sold in a single
sale are or, in the opinion of counsel satisfactory to the Company and the
Designated Holder, each in their reasonable judgment, may be distributed to the
public without any limitation as to volume pursuant to Rule 144 (or any
successor provision then in effect) under the Securities Act or (iii) such
Registrable Securities are proposed to be sold or distributed by a Person not
entitled to the registration rights granted by this Agreement.

               (c) Holders of Registrable Securities. A Person is deemed to be a
holder of Registrable Securities whenever such Person owns of record Registrable
Securities. If the Company receives conflicting instructions, notices or
elections from two or more Persons with respect to the same Registrable
Securities, the Company may act upon the basis of the instructions, notice or
election received from the registered owner of such Registrable Securities.
Registrable Securities issuable upon exercise of an option or upon conversion of
another security shall be deemed outstanding for the purposes of this Agreement.

            3. Demand Registration.

               (a) Request for Demand Registration. At any time after twelve
months following the IPO Effectiveness Date, the General Atlantic Stockholders
may make a written request to the Company to register (such General Atlantic
Stockholders making such request being referred to hereinafter as the
"Initiating Holders"), under the Securities Act and under the securities or
"blue sky" laws of any jurisdiction reasonably designated by such holder or
holders, the number of Registrable Securities, the offer and sale of which shall
result in net proceeds (after expenses and underwriting commissions and
discounts) to such Initiating Holders of at least $5,000,000 (a "Demand
Registration"). The Company shall use its reasonable efforts to cause such
Demand Registration to become and remain effective not later than three (3)
months after it receives a request for a Demand Registration. The Company shall
not be required to effect more than one (1) Demand Registration at the request
of the General Atlantic Stockholders pursuant to this Section 3. Notwithstanding
the foregoing, if the amount of Registrable Securities requested by
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the Initiating Holders to be included in a Demand Registration is reduced
pursuant to Section 3(d) or 4(a), then a Demand Registration shall not be deemed
to have been effected at the request of such Initiating Holders. If at the time
of any request to register Registrable Securities pursuant to this Section 3(a),
the Company is engaged in, or has fixed plans to engage in within three (3)
months of the time of such request, a registered public offering or is engaged
in any other activity which, in the good faith determination of the Board of
Directors of the Company, would be adversely affected by the requested
registration to the material detriment of the Company, then the Company may at
its option direct that such request be delayed for a reasonable period not in
excess of three (3) months from the effective date of such offering or the date
of completion of such other material activity, as the case may be, such right to
delay a request to be exercised by the Company not more than once in any
one-year period. In addition, the Company shall not be required to effect any
Demand Registration within three (3) months after the effective date of any
other Registration Statement of the Company. Each request for a Demand
Registration by the Initiating Holders shall state the amount of the Registrable
Securities proposed to be sold and the intended method of disposition thereof.
Upon a request for a Demand Registration, the Company shall promptly take such
steps as are necessary or appropriate to prepare for the registration of the
Registrable Securities to be registered. Each of the Designated Holders (other
than the Initiating Holders) may, pursuant to and as limited by Section 4
hereof, offer its Registrable Securities under any such Demand Registration
pursuant to this Section 3.

               (b) Effective Demand Registration. A registration shall not
constitute a Demand Registration until it has become effective and remains
continuously effective for the lesser of (i) the period during which all
Registrable Securities registered in the Demand Registration are sold and (ii)
120 days; provided, however, that a registration shall not constitute a Demand
Registration if (x) after such Demand Registration has become effective, such
registration or the related offer, sale or distribution of Registrable
Securities thereunder is interfered with by any stop order, injunction or other
order or requirement of the SEC or other governmental agency or court for any
reason not attributable to the Initiating Holders and such interference is not
thereafter eliminated or (y) the conditions to closing specified in the
underwriting agreement, if any, entered into in connection with such Demand
Registration are not satisfied or waived, other than by reason of a failure by
the Initiating Holders.

               (c) Expenses. In any registration initiated as a Demand
Registration, the Company shall pay all Registration Expenses (other than
underwriting discounts and commissions) in connection therewith, whether or not
such Demand Registration becomes effective; provided, however, that each
Designated Holder participating in such Demand Registration shall bear the costs
of its own legal counsel.
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               (d) Underwriting Procedures. If the Initiating Holders holding a
majority of the Registrable Securities held by all of the Initiating Holders to
which the requested Demand Registration relates so elect, the Company shall use
its reasonable efforts to cause the offering of such Registrable Securities
pursuant to such Demand Registration to be in the form of a firm commitment
underwritten offering and the managing underwriter or underwriters selected for
such offering shall be the Approved Underwriter (as hereinafter defined)
selected in accordance with Section 3(e). In such event, if the Approved
Underwriter advises the Company in writing that in its opinion the aggregate
amount of such Registrable Securities requested to be included in such offering
is sufficiently large to have a material adverse effect on the success of such
offering, then the Company shall include in such registration only the aggregate
amount of Registrable Securities that in the opinion of the Approved Underwriter
may be sold without any such material adverse effect and shall reduce, first as
to the Company and then as to the Designated Holders as a group pro rata based
on the number of Registrable Securities requested to be included in such
registration.

               (e) Selection of Underwriters. If any Demand Registration of
Registrable Securities is in the form of an underwritten offering, the
Initiating Holders holding a majority of the Registrable Securities held by all
such Initiating Holders shall select and obtain an investment banking firm of
national reputation to act as the managing underwriter of the offering (the
"Approved Underwriter"); provided, however, that the Approved Underwriter shall,
in any case, be acceptable to the Company in its reasonable judgment.

            4. Piggy-Back Registration.

               (a) Piggy-Back Rights. At any time after the IPO Effectiveness
Date, if the Company proposes to file a registration statement under the
Securities Act with respect to an offering by the Company for its own account or
for the account of the Initiating Holders pursuant to Section 3 of any class of
security (other than a registration statement on Form S-4 or S-8 or any
successor thereto), then the Company shall give written notice of such proposed
filing to each of the Designated Holders of Registrable Securities (other than
any Initiating Holders) at least thirty (30) days before the anticipated filing
date, and such notice shall describe the proposed registration and distribution
and offer such Designated Holders (other than any Initiating Holders) the
opportunity to register the number of Registrable Securities as each such holder
may request. The Company and/or Initiating Holders shall, and shall use
reasonable efforts to cause the managing underwriter or underwriters of a
proposed underwritten offering (the "Company Underwriter") to, permit the
Designated Holders of Registrable Securities who have requested in writing to
participate in the registration for such offering to include such Registrable
Securities in such offering on the same terms and conditions as the securities
of the Company included therein. In connection with any offering under this
Section 4(a) involving an underwriting, the Company and/or Initiating Holders
shall not be
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required to include any Registrable Securities in such underwriting unless the
holders thereof accept the terms of the underwriting as agreed upon between the
Company and the Company Underwriter, and then only in such quantity as will not,
in the opinion of the Company Underwriter, jeopardize the success of the
offering by the Company and/or Initiating Holders. If in the written opinion of
the Company Underwriter the registration of all or part of the Registrable
Securities which the Designated Holders have requested to be included would
materially adversely affect such public offering, then the Company shall be
required to include in the underwriting, to the extent of the amount that the
Company Underwriter believes may be sold without causing such adverse effect,
first, all of the securities to be offered for the account of the Company, if
the Company initiated such registration; second, the Registrable Securities to
be offered for the account of the Designated Holders as a group, pro rata based
on the number of Registrable Securities proposed to be offered for the account
of such Designated Holders; and third, any other securities requested to be
included in such underwriting.

               (b) Expenses. The Company shall bear all Registration Expenses
(other than underwriting discounts and commissions) in connection with any
registration pursuant to this Section 4; provided, however, that each Designated
Holder participating in such registration shall bear the costs of its own legal
counsel.

            5. Holdback Agreements.

               (a) Restrictions on Public Sale by Designated Holders. Each
Designated Holder of Registrable Securities agrees not to effect any public sale
or distribution of any Registrable Securities being registered or of any
securities convertible into or exchangeable or exercisable for such Registrable
Securities, including a sale pursuant to Rule 144 under the Securities Act,
during the 180-day period beginning on the effective date of such registration
statement (except as part of such registration), if and to the extent requested
by the Company or Initiating Holders in the case of a non-underwritten public
offering or if and to the extent requested by the Company Underwriter in the
case of an underwritten public offering.

               (b) Restrictions on Public Sale by the Company. The Company
agrees not to effect any public sale or distribution of any of its securities,
or any securities convertible into or exchangeable or exercisable for such
securities (except pursuant to registrations on Form S-4 or S-8 or any successor
thereto), during the period beginning on the effective date of any registration
statement in which the Designated Holders of Registrable Securities are
participating and ending on the earlier of (i) the date on which all Registrable
Securities registered on such registration statement are sold and (ii) three (3)
months after the effective date of such registration statement.
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                                                                               9

            6. Registration Procedures.

               (a) Obligations of the Company. Whenever registration of
Registrable Securities has been requested pursuant to Section 3 or 4 of this
Agreement, the Company shall use its reasonable efforts to effect the
registration and sale of such Registrable Securities in accordance with the
intended method of distribution thereof as quickly as practicable, and in
connection with any such request, the Company shall, as expeditiously as
possible:

                   (i) use its reasonable efforts to prepare and file with the
SEC a registration statement on any form for which the Company then qualifies or
which counsel for the Company shall deem appropriate and which form shall be
available for the sale of such Registrable Securities in accordance with the
intended method of distribution thereof, and use its reasonable efforts to cause
such registration statement to become effective; provided, however, that (x)
before filing a registration statement or prospectus or any amendments or
supplements thereto, the Company shall provide counsel selected by the
Designated Holders holding a majority of the Registrable Securities being
registered in such registration ("Holders' Counsel") and any other Inspector (as
hereinafter defined) with an adequate and appropriate opportunity to participate
in the preparation of such registration statement and each prospectus included
therein (and each amendment or supplement thereto) to be filed with the SEC,
which documents shall be subject to the review of Holders' Counsel, and (y) the
Company shall notify the Holders' Counsel and each seller of Registrable
Securities of any stop order issued or threatened by the SEC and take all
reasonable action required to prevent the entry of such stop order or to remove
it if entered;

                   (ii) prepare and file with the SEC such amendments and
supplements to such registration statement and the prospectus used in connection
therewith as may be necessary to keep such registration statement effective for
the lesser of (x) three (3) months and (y) such shorter period which will
terminate when all Registrable Securities covered by such registration statement
have been sold, and comply with the provisions of the Securities Act with
respect to the disposition of all securities covered by such registration
statement during such period in accordance with the intended methods of
disposition by the sellers thereof set forth in such registration statement;

                   (iii) as soon as reasonably possible, furnish to each seller
of Registrable Securities, prior to filing a registration statement, copies of
such registration statement as is proposed to be filed, and thereafter such
number of copies of such registration statement, each amendment and supplement
thereto (in each case including all exhibits thereto), the prospectus included
in such registration statement (including each preliminary prospectus) and such
other documents as each such seller may reasonably request in order to
facilitate the disposition of the Registrable Securities owned by such seller;
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                                                                              10

                   (iv) use its reasonable efforts to register or qualify such
Registrable Securities under such other securities or "blue sky" laws of such
jurisdictions as any seller of Registrable Securities may reasonably request,
and to continue such qualification in effect in such jurisdiction for the lesser
of (x) three (3) months and (y) such shorter period which will terminate when
all Registrable Securities covered by such registration statement have been
sold, and do any and all other acts and things which may be reasonably necessary
or advisable to enable any such seller to consummate the disposition in such
jurisdictions of the Registrable Securities owned by such seller; provided,
however, that the Company shall not be required to (x) qualify generally to do
business in any jurisdiction where it would not otherwise be required to qualify
but for this Section 6(a)(iv), (y) subject itself to taxation in any such
jurisdiction or (z) consent to general service of process in any such
jurisdiction;

                   (v) use its reasonable efforts to cause the Registrable
Securities covered by such registration statement to be registered with or
approved by such other governmental agencies or authorities as may be necessary
by virtue of the business and operations of the Company to enable the seller or
sellers of Registrable Securities to consummate the disposition of such
Registrable Securities;

                   (vi) upon discovery that, or upon the happening of any event
as a result of which, the prospectus included in a registration statement
covering Registrable Securities contains an untrue statement of a material fact
or omits to state any material fact required to be stated therein or necessary
to make the statements therein not misleading in light of the circumstances
under which they were made, (x) promptly prepare a supplement or amendment to
such prospectus and furnish to each seller of Registrable Securities a
reasonable number of copies of a supplement to or an amendment of such
prospectus as may be necessary so that, after delivery to the purchasers of such
Registrable Securities, such prospectus shall not contain an 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 in light of the
circumstances under which they were made and (y) immediately prior to the
preparation of such amendment or supplement to such prospectus, notify each
seller of Registrable Securities of the anticipated preparation thereof;

                   (vii) enter into and perform customary agreements (including
an underwriting agreement in customary form with the Approved Underwriter or
Company Underwriter, if any, selected as provided in Section 3 or 4) and take
such other actions as are prudent and reasonably required in order to expedite
or facilitate the disposition of such Registrable Securities;

                   (viii) make available for inspection by any seller of
Registrable Securities, any managing underwriter participating in any
disposition pursuant to such registration statement, Holders' Counsel and any
attorney, accountant or other agent retained by any such seller or any managing
underwriter
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                                                                              11

(each, an "Inspector" and collectively, the "Inspectors"), all financial and
other records, pertinent corporate documents and properties of the Company and
its subsidiaries (collectively, the "Records") as shall be reasonably necessary
to enable them to exercise their due diligence responsibility, and cause the
Company's and its subsidiaries' officers, directors and employees, and the
independent public accountants of the Company, to supply all information
reasonably requested by any such Inspector in connection with such registration
statement. Records that the Company determines, in good faith, to be
confidential and which it notifies the Inspectors are confidential shall not be
disclosed by the Inspectors unless (x) the disclosure of such Records is
necessary to avoid or correct a misstatement or omission in the registration
statement, (y) the release of such Records is ordered pursuant to a subpoena or
other order from a court of competent jurisdiction or (z) the information in
such Records was known to the Inspectors on a non-confidential basis prior to
its disclosure by the Company or has been made generally available to the
public. Each seller of Registrable Securities agrees that it shall, upon
learning that disclosure of such Records is sought in a court of competent
jurisdiction, give notice to the Company and allow the Company, at the Company's
expense, to undertake appropriate action to prevent disclosure of the Records
deemed confidential;

                   (ix) if such sale is pursuant to an underwritten offering,
use its reasonable efforts to obtain a "cold comfort" letter from the Company's
independent public accountants in customary form and covering such matters of
the type customarily covered by "cold comfort" letters as Holders' Counsel or
the managing underwriter reasonably request;

                   (x) use its reasonable efforts to furnish, at the request of
any seller of Registrable Securities on the date such securities are delivered
to the underwriters for sale pursuant to such registration or, if such
securities are not being sold through underwriters, on the date the registration
statement with respect to such securities becomes effective, an opinion, dated
such date, of counsel representing the Company for the purposes of such
registration, addressed to the underwriters, if any, and to the seller making
such request, covering such legal matters with respect to the registration in
respect of which such opinion is being given as such seller may reasonably
request and are customarily included in such opinions;

                   (xi) otherwise use its reasonable efforts to comply with all
applicable rules and regulations of the SEC, and make available to its security
holders, as soon as reasonably practicable but no later than fifteen (15) months
after the effective date of the registration statement, an earnings statement
covering a period of twelve (12) months beginning after the effective date of
the registration statement, in a manner which satisfies the provisions of
Section 11(a) of the Securities Act and Rule 158 thereunder;
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                   (xii) cause all such Registrable Securities to be listed on
each securities exchange on which similar securities issued by the Company are
then listed, provided, that the applicable listing requirements are satisfied;

                   (xiii) cooperate with each seller of Registrable Securities
and each underwriter participating in the disposition of such Registrable
Securities and their respective counsel in connection with any filings required
to be made with the National Association of Securities Dealers, Inc. (the
"NASD"); and

                   (xiv) use reasonable efforts to take all other steps
necessary to effect the registration of the Registrable Securities contemplated
hereby.

               (b) Seller Information. The Company may require each seller of
Registrable Securities as to which any registration is being effected to furnish
to the Company such information regarding the distribution of such securities as
the Company may from time to time reasonably request in writing.

               (c) Notice to Discontinue. Each Designated Holder of Registrable
Securities agrees that, upon receipt of any notice from the Company of the
happening of any event of the kind described in Section 6(a)(vi), such
Designated Holder shall forthwith discontinue disposition of Registrable
Securities pursuant to the registration statement covering such Registrable
Securities until such Designated Holder's receipt of the copies of the
supplemented or amended prospectus contemplated by Section 6(a)(vi) and, if so
directed by the Company, such Designated Holder shall deliver to the Company (at
the Company's expense) all copies, other than permanent file copies then in such
Designated Holder's possession, of the prospectus covering such Registrable
Securities which is current at the time of receipt of such notice. If the
Company shall give any such notice, the Company shall extend the period during
which such registration statement shall be maintained effective pursuant to this
Agreement (including, without limitation, the period referred to in Section
6(a)(ii)) by the number of days during the period from and including the date of
the giving of such notice pursuant to Section 6(a)(vi) to and including the date
when the Designated Holder shall have received the copies of the supplemented or
amended prospectus contemplated by and meeting the requirements of Section
6(a)(vi).

               (d) Registration Expenses. The Company shall pay all expenses
(other than as set forth in Sections 3(c) and 4(b)) arising from or incident to
the performance of, or compliance with, this Agreement, including, without
limitation, (i) SEC, stock exchange and NASD registration and filing fees, (ii)
all fees and expenses incurred in complying with securities or "blue sky" laws
(including reasonable fees, charges and disbursements of counsel in connection
with "blue sky" qualifications of the Registrable Securities), (iii) all
printing, messenger and delivery expenses, (iv) the fees, charges and
disbursements of counsel to the Company and of its independent public
accountants and any other accounting and legal fees, charges and expenses
incurred by the Company (including, without limitation, any expenses
<PAGE>   16
                                                                              13

arising from any special audits incident to or required by any registration or
qualification) and (v) any liability insurance or other premiums for insurance
obtained in connection with any Demand Registration or piggy-back registration
pursuant to the terms of this Agreement, regardless of whether such registration
statement is declared effective. All of the expenses described in this Section
6(d) are referred to herein as "Registration Expenses".

            7. Indemnification; Contribution.

               (a) Indemnification by the Company. The Company agrees to
indemnify and hold harmless, to the fullest extent permitted by law, each
Designated Holder, its officers, directors, trustees, partners, members,
employees, advisors and agents and each Person who controls (within the meaning
of the Securities Act or the Exchange Act) such Designated Holder from and
against any and all losses, claims, damages, liabilities and expenses (including
reasonable costs of investigation) arising out of or based upon any untrue, or
allegedly untrue, statement of a material fact contained in any registration
statement, prospectus or preliminary prospectus or notification or offering
circular (as amended or supplemented if the Company shall have furnished any
amendments or supplements thereto) or arising out of or based upon any omission
or alleged omission to state therein a material fact required to be stated
therein or necessary to make the statements therein not misleading, except
insofar as the same are caused by or contained in any information concerning
such Designated Holder furnished in writing to the Company by such Designated
Holder expressly for use therein. The Company shall also provide customary
indemnities to any underwriters of the Registrable Securities, their officers,
directors and employees and each Person who controls such underwriters (within
the meaning of the Securities Act and the Exchange Act) to the same extent as
provided above with respect to the indemnification of the Designated Holders of
Registrable Securities.

               (b) Indemnification by Designated Holders. In connection with any
registration statement in which a Designated Holder is participating pursuant to
Section 3 or 4 hereof, each such Designated Holder shall furnish to the Company
in writing such information with respect to such Designated Holder as the
Company may reasonably request or as may be required by law for use in
connection with any such registration statement or prospectus and each
Designated Holder agrees to indemnify and hold harmless, to the fullest extent
permitted by law, the Company, any underwriter retained by the Company and their
respective directors, officers, employees and each Person who controls the
Company or such underwriter (within the meaning of the Securities Act and the
Exchange Act) to the same extent as the foregoing indemnity from the Company to
the Designated Holders, but only with respect to any such information with
respect to such Designated Holder furnished in writing to the Company by such
Designated Holder expressly for use therein; provided, however, that the total
amount to be indemnified by such Designated Holder pursuant to this Section 7(b)
shall be limited to the net proceeds received by
<PAGE>   17
                                                                              14

such Designated Holder in the offering to which the registration statement or
prospectus relates.

               (c) Conduct of Indemnification Proceedings. Any Person entitled
to indemnification hereunder (the "Indemnified Party") agrees to give prompt
written notice to the indemnifying party (the "Indemnifying Party") after the
receipt by the Indemnified Party of any written notice of the commencement of
any action, suit, proceeding or investigation or threat thereof made in writing
for which the Indemnified Party intends to claim indemnification or contribution
pursuant to this Agreement; provided, however, that the failure so to notify the
Indemnifying Party shall not relieve the Indemnifying Party of any liability
that it may have to the Indemnified Party hereunder. If notice of commencement
of any such action is given to the Indemnifying Party as above provided, the
Indemnifying Party shall be entitled to participate in and, to the extent it may
wish, jointly with any other Indemnifying Party similarly notified, to assume
the defense of such action at its own expense, with counsel chosen by it and
satisfactory to such Indemnified Party. The Indemnified Party shall have the
right to employ separate counsel in any such action and participate in the
defense thereof, but the fees and expenses of such counsel (other than
reasonable costs of investigation) shall be paid by the Indemnified Party unless
(i) the Indemnifying Party agrees to pay the same, (ii) the Indemnifying Party
fails to assume the defense of such action with counsel satisfactory to the
Indemnified Party in its reasonable judgment or (iii) the named parties to any
such action (including any impleaded parties) have been advised by such counsel
that either (x) representation of such Indemnified Party and the Indemnifying
Party by the same counsel would be inappropriate under applicable standards of
professional conduct or (y) there may be one or more legal defenses available to
it which are different from or additional to and in conflict with those
available to the Indemnifying Party and in such event, the Indemnifying Party
shall pay the fees and expenses of counsel to the Indemnified Party only to the
extent that such separate counsel is necessary under such applicable standards
of professional conduct in the case of the foregoing clause (x) or to the extent
necessary to avoid any conflict in the case of the foregoing clause (y). In
either of such cases, the Indemnifying Party shall not have the right to assume
the defense of such action on behalf of such Indemnified Party. No Indemnifying
Party shall be liable for any settlement entered into without its written
consent, which consent shall not be unreasonably withheld.

               (d) Contribution. If the indemnification provided for in this
Section 8 from the Indemnifying Party is unavailable to an Indemnified Party
hereunder in respect of any losses, claims, damages, liabilities or expenses
referred to therein, then the Indemnifying Party, in lieu of indemnifying such
Indemnified Party, shall contribute to the amount paid or payable by such
Indemnified Party as a result of such losses, claims, damages, liabilities or
expenses in such proportion as is appropriate to reflect the relative fault of
the Indemnifying Party and Indemnified Party in connection with the actions
which resulted in such losses, claims, damages, liabilities or expenses, as well
as any other relevant equitable considerations. The
<PAGE>   18
                                                                              15

relative faults of such Indemnifying Party and Indemnified Party shall be
determined by reference to, among other things, whether any action in question,
including any untrue or alleged untrue statement of a material fact or omission
or alleged omission to state a material fact, has been made by, or relates to
information supplied by, such Indemnifying Party or Indemnified Party, and the
parties' relative intent, knowledge, access to information and opportunity to
correct or prevent such action. The amount paid or payable by a party as a
result of the losses, claims, damages, liabilities and expenses referred to
above shall be deemed to include, subject to the limitations set forth in
Sections 7(a), 7(b) and 7(c), any legal or other fees, charges or expenses
reasonably incurred by such party in connection with any investigation or
proceeding; provided that the total amount to be indemnified by such Designated
Holder shall be limited to the net proceeds received by such Designated Holder
in the offering.

             The parties hereto agree that it would not be just and equitable if
contribution pursuant to this Section 8(d) were determined by pro rata
allocation or by any other method of allocation which does not take account of
the equitable considerations referred to in the immediately preceding paragraph.
No person guilty of fraudulent misrepresentation (within the meaning of Section
11(f) of the Securities Act) shall be entitled to contribution from any person.

            8. Rule 144. From and after the IPO Effectiveness Date, the Company
covenants that it shall file any reports required to be filed by it under the
Exchange Act and that it shall take such further action as each Designated
Holder of Registrable Securities may reasonably request (including providing any
information necessary to comply with Rules 144 and 144A under the Securities
Act), all to the extent required from time to time to enable such Designated
Holder to sell Registrable Securities without registration under the Securities
Act within the limitation of the exemptions provided by (a) Rule 144 under the
Securities Act, as such rules may be amended from time to time, or (b) any
similar rules or regulations hereafter adopted by the SEC. The Company shall,
upon the request of any Designated Holder of Registrable Securities, deliver to
such Designated Holder a written statement as to whether it has complied with
such requirements.

            9. Miscellaneous.

               (a) Recapitalizations, Exchanges, etc. The provisions of this
Agreement shall apply, to the full extent set forth herein with respect to (i)
the shares of Common Stock and (ii) to any and all equity securities of the
Company or any successor or assign of the Company (whether by merger,
consolidation, sale of assets or otherwise) which may be issued in respect of,
in conversion of, in exchange for or in substitution of, the shares of Common
Stock and shall be appropriately adjusted for any stock dividends, splits,
reverse splits, combinations, recapitalizations and the like occurring after the
date hereof. The Company shall cause any successor or assign (whether by sale,
merger or otherwise) to enter into a new registration rights
<PAGE>   19
                                                                              16

agreement with the Designated Holders on terms substantially the same as this
agreement as a condition of any such transaction.

               (b) No Inconsistent Agreements. The Company shall not enter into
any agreement with respect to its securities that is inconsistent with the
rights granted to the Designated Holders in this Agreement or grant any
additional registration rights to any Person or with respect to any securities
which are not Registrable Securities which are prior in right to or inconsistent
with the rights granted in this Agreement.

               (c) Remedies. The Designated Holders, in addition to being
entitled to exercise all rights granted by law, including recovery of damages,
shall be entitled to specific performance of their rights under this Agreement.
The Company agrees that monetary damages would not be adequate compensation for
any loss incurred by reason of a breach by it of the provisions of this
Agreement and hereby agrees to waive in any action for specific performance the
defense that a remedy at law would be adequate.

               (d) Amendments and Waivers. Except as otherwise provided herein,
the provisions of this Agreement may not be amended, modified or supplemented,
and waivers or consents to departures from the provisions hereof may not be
given unless consented to in writing by (i) the Company, (ii) the General
Atlantic Stockholders holding Registrable Securities representing (after giving
effect to any adjustments) at least 80% of the aggregate number of Registrable
Securities owned by all of the General Atlantic Stockholders, (iii) the holders
of Registrable Securities representing (after giving effect to any adjustments)
at least 60% of (x) the aggregate number of Registrable Securities owned by all
of the Dow Jones Stockholders plus (y) the aggregate number of Registrable
Securities owned by all of Walton Stockholders and (iv) the PSE Stockholders
holding Registrable Securities representing (after giving effect to any
adjustments) at least 80% of the aggregate number of Registrable Securities
owned by all of the PSE Stockholders. Any such written consent shall be binding
upon the Company and all of the Designated Holders.

               (e) Notices. All notices, demands and other communications
provided for or permitted hereunder shall be made in writing and shall be made
by registered or certified first-class mail, return receipt requested,
telecopier, courier service, overnight mail or personal delivery:

                   (i)   if to the Company:

                         OptiMark Technologies, Inc.
                         530 Main Avenue
                         Durango, CO 81301
                         Telecopy: (970) 247-8844
                         Attention: William A. Lupien
<PAGE>   20
                                                                              17

                         with a copy to:

                         Ducker, Seawell & Montgomery, P.C.
                         One Civic Center Plaza
                         1560 Broadway, Suite 1500
                         Denver, CO 80202
                         Telecopy: (303) 861-4017
                         Attention: Bruce Ducker, Esq.

                   (ii)  if to GAP LP or GAP Coinvestment:

                         c/o General Atlantic Service Corporation
                         3 Pickwick Plaza
                         Greenwich, Connecticut 06830
                         Telecopy: (203) 622-4099
                         Attention: Stephen P. Reynolds

                         with a copy to:

                         Paul, Weiss, Rifkind, Wharton & Garrison
                         1285 Avenue of the Americas
                         New York, New York 10019-6064
                         Telecopy: (212) 757-3990
                         Attention: Matthew Nimetz, Esq.

                   (iii) if to Dow Jones:

                         Dow Jones & Company, Inc.
                         200 Liberty Street
                         New York, New York 10281
                         Telecopy: (212) 416-2524
                         Attention: John Goggins, Esq.

                   (iv)  if to Walton:

                         The Llama Company
                         One McIlroy Plaza, Suite 302
                         Fayetteville, AR 72701
                         Telecopy: (501) 444-4042
                         Attention: Alice L. Walton
<PAGE>   21
                                                                              18

                   (v)   if to PSE:

                         The Pacific Stock Exchange Incorporated
                         301 Pine Street
                         San Francisco, CA 94104
                         Telecopy: (415) 393-4150
                         Attention: John C. Katovich, Esq.

                         with a copy to:

                         Howard, Rice, Nemerovski,
                           Canady, Falk & Rabkin
                         A Professional Corporation
                         Three Embarcadero Center
                         Suite 700
                         San Francisco, CA 94111
                         Telecopy: (415) 399-3041
                         Attention: Timothy S. McCann, Esq.

                   (vi)  if to any other Designated Holder, at its address as it
                         appears on the record books of the Company.

               All such notices and communications shall be deemed to have been
duly given when delivered by hand, if personally delivered; when delivered by
courier or overnight mail, if delivered by commercial courier service or
overnight mail; five (5) Business Days after being deposited in the mail,
postage prepaid, if mailed; and when receipt is mechanically acknowledged, if
telecopied.

               (f) Successors and Assigns; Third Party Beneficiaries. This
Agreement shall inure to the benefit of and be binding upon the successors and
assigns of each of the parties hereto. The Demand Registration rights and other
rights of the General Atlantic Stockholders contained in Section 3 of this
Agreement shall be, with respect to any Registrable Security, (i) automatically
transferred among the General Atlantic Stockholders and (ii) in all other cases,
transferred only with the consent of the Company. The "incidental" registration
rights and other rights of each of the Designated Holders contained in this
Agreement may be, with respect to any Registrable Security, (i) automatically
transferred among the General Atlantic Stockholders, (ii) automatically
transferred among the Dow Jones Stockholders, (iii) automatically transferred
among the Walton Stockholders and (v) automatically transferred among the PSE
Stockholders. All of the obligations of the Company hereunder shall survive any
such transfer. No Person other than the parties hereto and their successors and
permitted assigns is intended to be a beneficiary of any of the rights granted
hereunder.
<PAGE>   22
                                                                              19

               (g) Counterparts. This Agreement may be executed in any number of
counterparts and by the parties hereto in separate counterparts, each of which
when so executed shall be deemed to be an original and all of which taken
together shall constitute one and the same agreement.

               (h) Headings. The headings in this Agreement are for convenience
of reference only and shall not limit or otherwise affect the meaning hereof.

               (i) GOVERNING LAW. THIS AGREEMENT SHALL BE GOVERNED BY AND
CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK WITHOUT REGARD TO
THE PRINCIPLES OF CONFLICTS OF LAW THEREOF.

               (j) Severability. If any one or more of the provisions contained
herein, or the application thereof in any circumstances, is held invalid,
illegal or unenforceable in any respect for any reason, the validity, legality
and enforceability of any such provision in every other respect and of the
remaining provisions hereof shall not be in any way impaired, it being intended
that all of the rights and privileges of the Designated Holders shall be
enforceable to the fullest extent permitted by law.

               (k) Entire Agreement. This Agreement is intended by the parties
as a final expression of their agreement and intended to be a complete and
exclusive statement of the agreement and understanding of the parties hereto in
respect of the subject matter contained herein. There are no restrictions,
promises, warranties or undertakings, other than those set forth or referred to
herein and in the Stock Purchase Agreement. This Agreement supersedes all prior
agreements and understandings between the parties with respect to such subject
matter.

               (l) Further Assurances. Each of the parties shall execute such
documents and perform such further acts as may be reasonably required or
desirable to carry out or to perform the provisions of this Agreement.
<PAGE>   23
                                                                              20

            IN WITNESS WHEREOF, the undersigned have executed, or have caused to
be executed, this Agreement on the date first written above.

                       OPTIMARK TECHNOLOGIES, INC.

                       By: /s/ William A. Lupien
                          -------------------------------------
                           Name: William A. Lupien
                           Title: Chairman & C.E.O.

                       GENERAL ATLANTIC PARTNERS 35, L.P.

                       By: GENERAL ATLANTIC PARTNERS, LLC,
                           Its General Partner

                           By: /s/ J. Michael Cline
                              -------------------------------------
                               Name: J. Michael Cline
                               Title: A Managing Member

                       GAP COINVESTMENT PARTNERS, L.P.

                       By: /s/ J. Michael Cline
                          -------------------------------------
                       Name: J. Michael Cline
                       Title: A General Partner

                       DOW JONES & COMPANY, INC.

                       By: /s/ Carl M. Valenti
                          -------------------------------------
                           Name: Carl M. Valenti
                           Title: Senior Vice President

                       /s/ Alice L. Walton
                       -----------------------------------------
                           Alice L. Walton

                       THE PACIFIC STOCK EXCHANGE INCORPORATED

                       By: /s/ John C. Katovich
                          -------------------------------------
                       Name: John C. Katovich
                       Title: Sr. Vice President, General Counsel
                              and Director of Legal Affairs<PAGE>   1

                                                                     Exhibit 4.5

                                    AMENDMENT
                                       TO
                            STOCK PURCHASE AGREEMENT
                                       AND
                          REGISTRATION RIGHTS AGREEMENT

            THIS AMENDMENT (this "Amendment"), dated as of March 19, 1997 among
OptiMark Technologies, Inc. (the "Company"), General Atlantic Partners 35, L.P.
("GAP 35"), GAP Coinvestment Partners, L.P. ("GAP Coinvestment"), Dow Jones &
Company, Inc. ("Dow") and Alice L. Walton ("Walton"; and, together with GAP 35,
GAP Coinvestment and Dow, the "Investors") amends (i) that certain Stock
Purchase Agreement, dated August 27, 1996, as amended on October 25, 1996 (the
"Stock Purchase Agreement") among the Company and the Investors and (ii) that
certain Registration Rights Agreement, dated as of August 27, 1996 (the
"Registration Rights Agreement"), among the Company, the Investors and The
Pacific Stock Exchange Incorporated.

            WHEREAS, pursuant to the Stock Purchase Agreement, the Investors
agreed to purchase, and the Company agreed to sell, shares of Series A
Convertible Participating Preferred Stock, par value $.O1 per share, of the
Company in two sequential closings;

            WHEREAS, on August 27, 1996, the Company and the Investors
consummated the First Closing (as defined in the Stock Purchase Agreement);

            WHEREAS, concurrent with the execution of this Amendment, the
Investors have agreed to waive a certain condition to the Second Closing (as
defined in the Stock Purchase Agreement) and consummate the Second Closing; and

            WHEREAS, in order to induce the Investors to waive that certain
condition to the Second Closing and consummate the Second Closing, the Company
has agreed to issue to each of the Investors a warrant to purchase Common Stock,
par value $.01 per share, of the Company.

            NOW, THEREFORE, in consideration of the premises and for other good
and valuable consideration, the receipt and adequacy of which is hereby
acknowledged, the parties hereto agree as follows:

            1. Amendment to the Stock Purchase Agreement.

                  (a) Section 2.3(a) of the Stock Purchase Agreement is hereby
deleted in its entirety and replaced with the following:

            "(a) Subject to Section 2.3(b), the Second Closing shall occur on
March 19, 1997."

<PAGE>   2

                                                                               2

                 (b) Section 2.3(b) of the Stock Purchase Agreement is hereby
amended to add the following as subsection (vii):

            "(vii) Each of the Investors shall have received a warrant,
            substantially in the form attached hereto as Exhibit A (each, a
            "Warrant" and collectively, the "Warrants"), exercisable into that
            percentage of outstanding shares of Common Stock as set forth
            opposite such Investor's name below:

                     Investor        Percentage of Common Stock
                     --------        --------------------------

                      GAP 35                  4.13 %

               GAP Coinvestment               0.87 %

                       Dow                     2.5 %

                      Walton                   0.5 %"

                  (c) The definition of "Transaction Documents" in the Stock
Purchase Agreement is hereby amended by deleting it entirely and replacing it
with the following:

            "Transaction Documents" means collectively this Agreement, the
            Certificate of Designation, the Stockholders Agreement, the
            Registration Rights Agreement, the Employment, Trade Secret and
            NonCompetition Agreements between the Company and Messrs. Lupien and
            Rickard, the PSE-OptiMark Agreement, the PSE Revenue Sharing
            Agreement, the PSE Warrant and each Warrant."

            2. Amendment to the Registration Rights Agreement.

                  (a) The definition of "Registrable Securities" in the
Registration Rights Agreement is hereby amended by deleting part (d) of such
definition in its entirety and replacing it with the following:

            "(d) to the extent exercisable at the time such amount of
            Registrable Securities is to be determined, any and all shares of
            Common Stock issuable to (i) PSE upon exercise of the PSE Warrant
            and (ii) each Investor (as defined in the Stock Purchase Agreement)
            upon exercise of their respective Warrants (as defined in the Stock
            Purchase Agreement)."

<PAGE>   3

                                                                               3

                  (b) It is understood by the parties hereto that the above
amendment to the Registration Rights Agreement shall become effective upon the
written consent of The Pacific Stock Exchange Incorporated.

            3. Miscellaneous.

                  (a) Governing Law. This Amendment shall be governed by and
construed in accordance with the laws of the State of New York applicable to
agreements made and to be performed entirely within such State.

                  (b) Assignment. This Amendment shall be binding upon the
successors and permitted assigns of the parties.

                  (c) Counterparts. This Amendment may be executed by the
parties hereto in separate counterparts, each of which when so executed and
delivered shall be an original but all such counterparts together shall
constitute one and the same instrument. Each counterpart may consist of a number
of copies hereof each signed by less than all, but together signed by all of the
parties hereto.

            IN WITNESS WHEREOF, the parties have executed this Amendment as of
the date first above written.

                                     OptiMark Technologies, Inc.

                                     By: /s/ Alan S. Danson
                                         --------------------------------------
                                         Name: Alan S. Danson
                                         Title: Senior Vice President

                                     General Atlantic Partners 35, L.P.

                                     By: General Atlantic Partners, LLC
                                          its General Partner

                                          By: /s/ Stephen P. Reynolds
                                              ---------------------------------
                                              A Managing Member

                                     GAP Coinvestment Partners, L.P.

                                     By: /s/ Stephen P. Reynolds
                                         --------------------------------------
                                         General Partner

<PAGE>   4

                                     Dow Jones & Company, Inc.

                                     By: /s/ Julian B. Childs
                                         --------------------------------------
                                         Name: Julian B. Childs
                                         Title: Executive Vice President

                                         /s/ Alice L. Walton
                                     ------------------------------------------
                                     Alice L. Walton

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