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                                                                     EXHIBIT 4.5



                             OPTIMARK HOLDINGS, INC.

                                 1999 STOCK PLAN

                       RESTRICTED STOCK PURCHASE AGREEMENT

      Unless otherwise defined herein, the terms defined in the 1999 Stock Plan
shall have the same defined meanings in this Restricted Stock Purchase Agreement
(the "Agreement").

I. NOTICE OF GRANT OF STOCK PURCHASE RIGHT

[Grantee's Name and Address]

      You have been granted the right to purchase Common Stock of the Company,
subject to the terms and conditions of the Plan and this Agreement, as follows:

      Grant Number                        _______________________

      Date of Grant                       _______________________

      Exercise Price Per Share            $______________________

      Total Number of Shares Subject      _______________________
       to This Stock Purchase Right

      Expiration Date                     _______________________

      YOU MUST EXERCISE THIS STOCK PURCHASE RIGHT BEFORE THE EXPIRATION DATE OR
IT WILL TERMINATE AND YOU WILL HAVE NO FURTHER RIGHT TO PURCHASE THE SHARES.

Non-Transferability of Stock Purchase Right.

      This Stock Purchase Right may not be transferred in any manner otherwise
than by will or by the laws of descent or distribution and may be exercised
during the lifetime of Optionee only by Optionee. The terms of the Plan and this
Agreement shall be binding upon the executors, administrators, heirs, successors
and assigns of the Optionee.

II.   AGREEMENT

      1. Sale of Stock. The Company hereby agrees to sell to the individual
named in the Notice of Grant of Stock Purchase Right (the "Purchaser"), and the
Purchaser hereby agrees to
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purchase the number of Shares set forth in the Notice of Grant of Stock Purchase
Right, at the exercise price per share set forth in the Notice of Grant of Stock
Purchase Right (the "Exercise Price"), and subject to the terms and conditions
of the Plan, which is incorporated herein by reference. Subject to Section 16(c)
of the Plan, in the event of a conflict between the terms and conditions of the
Plan and this Agreement, the terms and conditions of the Plan shall prevail.

      2. Payment of Purchase Price. Purchaser herewith delivers to the Company
the aggregate Exercise Price for the Shares by cash or check.

      3. Purchaser's Representations. In the event the Shares have not been
registered under the Securities Act of 1933, as amended, at the time this Stock
Purchase Right is exercised, the Optionee shall, if required by the Company,
concurrently with the exercise of all or any portion of this Stock Purchase
Right, deliver to the Company his or her Investment Representation Statement in
the form attached hereto as Exhibit B.

      4. Repurchase Option.

            (a) In the event the Purchaser's continuous status as a Service
Provider terminates for any or no reason (including death or Disability), the
Company shall, upon the date of such termination (as reasonably fixed and
determined by the Company), have an irrevocable, exclusive option for a period
of sixty (60) days from such date to repurchase up to that number of shares
which constitute the Unreleased Shares (as defined in Section 5) at the Exercise
Price per share (the "Repurchase Price") (the "Repurchase Option").

            (b) The Repurchase Option shall be exercised by the Company by
delivering written notice to the Purchaser or the Purchaser's executor (with a
copy to the Escrow Holder (as defined in Section 7)) AND, at the Company's
option, (i) by delivering to the Purchaser or the Purchaser's executor a check
in the amount of the aggregate Repurchase Price, or (ii) by the Company
canceling an amount of the Purchaser's indebtedness to the Company equal to the
aggregate Repurchase Price, or (iii) by a combination of (i) and (ii) so that
the combined payment and cancellation of indebtedness equals such aggregate
Repurchase Price. Upon delivery of such notice and the payment of the aggregate
Repurchase Price in any of the ways described above, the Company shall become
the legal and beneficial owner of the Unreleased Shares being repurchased and
all rights and interests therein or relating thereto, and the Company shall have
the right to retain and transfer to its own name the number of Unreleased Shares
being repurchased by the Company.

            (c) Whenever the Company shall have the right to repurchase the
Unreleased Shares hereunder, the Company may designate and assign one or more
employees, officers, directors or shareholders of the Company or other persons
or organizations to exercise all or a part of the Company's Repurchase Option to
purchase all or a part of the Unreleased Shares. If the Fair Market Value of the
Unreleased Shares to be repurchased on the date of such designation or
assignment (the "Repurchase FMV") exceeds the aggregate Repurchase Price of the
Unreleased Shares, then each such designee or assignee shall pay the Company
cash equal to the difference between the Repurchase FMV and the aggregate
Repurchase Price of Unreleased Shares to be purchased.


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            (d) If the Company or its assignee does not elect to exercise the
Repurchase Option conferred above by giving the requisite notice within sixty
(60) days following Purchaser's termination as a Service Provider, the
Repurchase Option shall terminate.

      5. Release of Shares From Repurchase Option.

            (a) [                        (     )] of the Shares shall be
released from the Company's Repurchase Option twelve months following the Date
of Grant (as set forth in the Notice of Grant of Stock Purchase Right) and
[                                 ] of the Shares shall be released each month
thereafter, provided in each case that the Purchaser's continuous status as a
Service Provider has not terminated prior to the date of any such release.

            (b) Any of the Shares which have not yet been released from the
Company's Repurchase Option are referred to herein as "Unreleased Shares."

            (c) The Shares which have been released from the Company's
Repurchase Option shall be delivered to the Purchaser at the Purchaser's request
(see Section 7).

      6. Restriction on Transfer. Except for the escrow described in Section 7
or transfer of the Shares to the Company or its assignees contemplated by this
Agreement, none of the Shares or any beneficial interest therein shall be
transferred, encumbered or otherwise disposed of in any way until the release of
such Shares from the Company's Repurchase Option in accordance with the
provisions of this Agreement, other than by will or the laws of descent and
distribution.

      7. Escrow of Shares.

            (a) To ensure the availability for delivery of the Purchaser's
Unreleased Shares upon exercise of the Repurchase Option by the Company, the
Purchaser shall, upon execution of this Agreement, deliver and deposit with an
escrow holder designated by the Company (the "Escrow Holder") the share
certificates representing the Unreleased Shares, together with the Assignment
Separate from Certificate (the "Stock Assignment") duly endorsed in blank,
attached hereto as Exhibit A-1. The Unreleased Shares and Stock Assignment shall
be held by the Escrow Holder, pursuant to the Joint Escrow Instructions of the
Company and Purchaser attached as Exhibit A-2 hereto, until such time as the
Company's Repurchase Option expires. As a further condition to the Company's
obligations under this Agreement, the spouse of Purchaser, if any, shall execute
and deliver to the Company the Consent of Spouse attached hereto as Exhibit A-3.

            (b) The Escrow Holder shall not be liable for any act it may do or
omit to do with respect to holding the Unreleased Shares in escrow and while
acting in good faith and in the exercise of its judgment.

            (c) If the Company or any assignee exercises its Repurchase Option
hereunder, the Escrow Holder, upon receipt of written notice of such option
exercise from the proposed transferee, shall take all steps necessary to
accomplish such transfer.


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            (d) When the Repurchase Option has been exercised or expires
unexercised or a portion of the Shares has been released from such Repurchase
Option, upon Purchaser's request the Escrow Holder shall promptly cause a new
certificate to be issued for such released Shares and shall deliver such
certificate to the Company or the Purchaser, as the case may be.

            (e) Subject to the terms hereof, the Purchaser shall have all the
rights of a shareholder with respect to such Shares while they are held in
escrow, including without limitation, the right to vote the Shares and receive
any cash dividends declared thereon. If, from time to time during the term of
the Company's Repurchase Option, there is (i) any stock dividend, stock split or
other change in the Shares, or (ii) any merger or sale of all or substantially
all of the assets or other acquisition of the Company, any and all new,
substituted or additional securities to which the Purchaser is entitled by
reason of the Purchaser's ownership of the Shares shall be immediately subject
to this escrow, deposited with the Escrow Holder and included thereafter as
"Shares" for purposes of this Agreement and the Company's Repurchase Option.

      8. Company's Right of First Refusal. Before any Shares held by Purchaser
or any transferee (either being sometimes referred to herein as the "Holder")
may be sold or otherwise transferred (including transfer by gift or operation of
law), the Company or its assignee(s) shall have a right of first refusal to
purchase the Shares on the terms and conditions set forth in this Section (the
"Right of First Refusal").

            (a) Notice of Proposed Transfer. The Holder of the Shares shall
deliver to the Company a written notice (the "Notice") stating: (i) the Holder's
bona fide intention to sell or otherwise transfer such Shares; (ii) the name of
each proposed purchaser or other transferee ("Proposed Transferee"); (iii) the
number of Shares to be transferred to each Proposed Transferee; and (iv) the
bona fide cash price or other consideration for which the Holder proposes to
transfer the Shares (the "Offered Price"), and the Holder shall offer the Shares
at the Offered Price to the Company or its assignee(s).

            (b) Exercise of Right of First Refusal. At any time within thirty
(30) days after receipt of the Notice, the Company and/or its assignee(s) may,
by giving written notice to the Holder, elect to purchase all, but not less than
all, of the Shares proposed to be transferred to any one or more of the Proposed
Transferees, at the purchase price determined in accordance with subsection (c)
below.

            (c) Purchase Price. The purchase price ("Purchase Price") for the
Shares purchased by the Company or its assignee(s) under this Section shall be
(i) the Offered Price in the case of Shares that are not Unreleased Shares, or
(ii) in the case of Shares that are Unreleased Shares, the lower of the Offered
Price or the Repurchase Price as defined in Section 4(a) hereof. If the Offered
Price includes consideration other than cash, the cash equivalent value of the
non-cash consideration shall be determined by the Board of Directors of the
Company in good faith.

            (d) Payment. Payment of the Purchase Price shall be made, at the
option of the Company or its assignee(s), (i) by cash or check, (ii) by
cancellation of all or a portion of any outstanding indebtedness of the Holder
to the Company (or, in the case of repurchase by an assignee,


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to the assignee), or (iii) by any combination thereof within thirty (30) days
after receipt of the Notice or in the manner and at the times set forth in the
Notice.

            (e) Holder's Right to Transfer. If all of the Shares proposed in the
Notice to be transferred to a given Proposed Transferee are not purchased by the
Company and/or its assignee(s) as provided in this Section, then the Holder may
sell or otherwise transfer such Shares to that Proposed Transferee at the
Offered Price or at a higher price, provided that such sale or other transfer is
consummated within one hundred twenty (120) days after the date of the Notice
and provided further that any such sale or other transfer is effected in
accordance with any applicable securities laws and the Proposed Transferee
agrees in writing that the provisions of this Section shall continue to apply to
the Shares in the hands of such Proposed Transferee. If the Shares described in
the Notice are not transferred to the Proposed Transferee within such period, a
new Notice shall be given to the Company, and the Company and/or its assignees
shall again be offered the Right of First Refusal before any Shares held by the
Holder may be sold or otherwise transferred.

            (f) Exception for Certain Family Transfers. Anything to the contrary
contained in this Section notwithstanding, the transfer of any or all of the
Shares during the Purchaser's lifetime or on the Purchaser's death by will or
intestacy to the Purchaser's immediate family or a trust for the benefit of the
Purchaser's immediate family shall be exempt from the provisions of this
Section, provided that the Purchaser notifies the Company in writing within
thirty (30) days of said transfer. "Immediate Family" as used herein shall mean
spouse, lineal descendant or antecedent, father, mother, brother or sister. In
such case, the transferee or other recipient shall receive and hold the Shares
so transferred subject to the provisions of this Agreement, including but not
limited to this Section and Section 4, and there shall be no further transfer of
such Shares except in accordance with the terms of this Section.

            (g) Termination of Right of First Refusal. The Right of First
Refusal shall terminate as to any Shares upon the date of the first sale of
Common Stock of the Company to the general public pursuant to a registration
statement filed with and declared effective by the Securities and Exchange
Commission under the 1933 Act.

      9. Restrictive Legends; Stop-Transfer Orders; Refusal to Transfer.

            (a) Purchaser understands and agrees that the Company shall cause
the legends set forth below or legends substantially equivalent thereto, to be
placed upon any certificate(s) evidencing ownership of the Shares together with
any other legends that may be required by the Company or by applicable state or
federal securities laws:

            THE SECURITIES REPRESENTED HEREBY HAVE NOT BEEN REGISTERED UNDER THE
            SECURITIES ACT OF 1933 (THE "ACT") AND MAY NOT BE OFFERED, SOLD OR
            OTHERWISE TRANSFERRED, PLEDGED OR HYPOTHECATED UNLESS AND UNTIL
            REGISTERED UNDER THE ACT OR, IN THE OPINION OF COUNSEL SATISFACTORY
            TO THE ISSUER OF THESE


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            SECURITIES, SUCH OFFER, SALE OR TRANSFER, PLEDGE OR HYPOTHECATION IS
            IN COMPLIANCE THEREWITH.

            THE SHARES REPRESENTED BY THIS CERTIFICATE ARE SUBJECT TO CERTAIN
            RESTRICTIONS ON TRANSFER, A RIGHT OF FIRST REFUSAL, AND A REPURCHASE
            OPTION HELD BY THE ISSUER OR ITS ASSIGNEE(S) AS SET FORTH IN THE
            RESTRICTED STOCK PURCHASE AGREEMENT BETWEEN THE ISSUER AND THE
            ORIGINAL HOLDER OF THESE SHARES, A COPY OF WHICH MAY BE OBTAINED AT
            THE PRINCIPAL OFFICE OF THE ISSUER. SUCH TRANSFER RESTRICTIONS,
            RIGHT OF FIRST REFUSAL AND REPURCHASE OPTION ARE BINDING ON
            TRANSFEREES OF THESE SHARES.

            (b) Stop-Transfer Notices. Purchaser agrees that, in order to ensure
compliance with the restrictions referred to herein, the Company may issue
appropriate "stop transfer" instructions to its transfer agent, if any, and
that, if the Company transfers its own securities, it may make appropriate
notations to the same effect in its own records.

            (c) Refusal to Transfer. The Company shall not be required (i) to
transfer on its books any Shares that have been sold or otherwise transferred in
violation of any of the provisions of this Agreement or (ii) to treat as owner
of such Shares or to accord the right to vote or pay dividends to any purchaser
or other transferee to whom such Shares shall have been so transferred.

      10. Lock-Up Period. Purchaser hereby agrees that, if so requested by the
Company or any representative of the underwriters (the "Managing Underwriter")
in connection with any registration of the offering of any securities of the
Company under the Securities Act, Purchaser shall not sell or otherwise transfer
any Shares or other securities of the Company during the 180-day period (or such
other period as may be requested in writing by the Managing Underwriter and
agreed to in writing by the Company) (the "Market Standoff Period") following
the effective date of a registration statement of the Company filed under the
Securities Act. Such restriction shall apply only to the first registration
statement of the Company to become effective under the Securities Act that
includes securities to be sold on behalf of the Company to the public in an
underwritten public offering under the Securities Act. The Company may impose
stop-transfer instructions with respect to securities subject to the foregoing
restrictions until the end of such Market Standoff Period.

      11. Tax Consequences. Set forth below is a brief summary as of the date of
grant of this Stock Purchase Right of some of the federal tax consequences of
exercise of this Stock Purchase Right and disposition of the Shares. THIS
SUMMARY IS NECESSARILY INCOMPLETE, AND THE TAX LAWS AND REGULATIONS ARE SUBJECT
TO CHANGE.

            (a) Exercise of Stock Purchase Right. Generally, no income will be
recognized by Purchaser in connection with the exercise of the stock purchaser
right for shares subject to the Repurchase Option, unless an election under
Section 83(b) of the Code is filed with the Internal Revenue Service within 30
days of the date of exercise of the right to purchase stock. The form for


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making this election is attached as Exhibit A-4 hereto. Otherwise, as the
Company's repurchase right lapses, Purchaser will recognize compensation income
in an amount equal to the difference between the Fair Market Value of the stock
at the time the Company's repurchase right lapses and the amount paid for the
stock, if any (the "Spread"). If Purchaser is an Employee or former Employee,
the Spread will be subject to tax withholding by the Company, and the Company
will be entitled to a tax deduction in the amount at the time the Purchaser
recognizes ordinary income with respect to a Stock Purchase Right.

            (b) Disposition of Shares. Upon disposition of the Shares, any gain
or loss is treated as capital gain or loss. If the Shares are held for at least
one year, any gain realized on disposition of the shares will be treated as
long-term capital gain for federal income tax purposes. Long-term capital gains
are grouped and netted by holding periods. Current net capital gains on assets
held for more than 12 months is capped at 20%. Capital losses are allowed in
full against capital gains, and up to $3,000 against other income.

      THE PURCHASER ACKNOWLEDGES THAT IT IS THE PURCHASER'S SOLE RESPONSIBILITY
AND NOT THE COMPANY'S TO FILE TIMELY THE ELECTION UNDER SECTION 83(b), EVEN IF
THE PURCHASER REQUESTS THE COMPANY OR ITS REPRESENTATIVES TO MAKE THIS FILING ON
THE PURCHASER'S BEHALF.

      12. No Guarantee of Continued Service. PURCHASER ACKNOWLEDGES AND AGREES
THAT THE RELEASE OF SHARES FROM THE REPURCHASE OPTION OF THE COMPANY PURSUANT TO
4 HEREOF IS EARNED ONLY BY CONTINUING SERVICE AS SERVICE PROVIDER AT THE WILL OF
THE COMPANY (NOT THROUGH THE ACT OF BEING HIRED OR PURCHASING SHARES HEREUNDER).
PURCHASER FURTHER ACKNOWLEDGES AND AGREES THAT THIS AGREEMENT, THE TRANSACTIONS
CONTEMPLATED HEREUNDER AND THE VESTING SCHEDULE SET FORTH HEREIN DO NOT
CONSTITUTE AN EXPRESS OR IMPLIED PROMISE OF CONTINUED ENGAGEMENT AS A SERVICE
PROVIDER FOR THE VESTING PERIOD, FOR ANY PERIOD, OR AT ALL, AND SHALL NOT
INTERFERE WITH PURCHASER'S RIGHT OR THE COMPANY'S RIGHT TO TERMINATE PURCHASER'S
RELATIONSHIP AS A SERVICE PROVIDER AT ANY TIME, WITH OR WITHOUT CAUSE.

      13. Notices. Any notice, demand or request required or permitted to be
given by either the Company or the Purchaser pursuant to the terms of this
Agreement shall be in writing and shall be deemed given when delivered
personally or deposited in the U.S. mail, First Class with postage prepaid, and
addressed to the parties at the addresses of the parties set forth at the end of
this Agreement or such other address as a party may request by notifying the
other in writing.

            Any notice to the Escrow Holder shall be sent to the Company's
address with a copy to the other party not sending the notice.

      14. No Waiver. Either party's failure to enforce any provision or
provisions of this Agreement shall not in any way be construed as a waiver of
any such provision or provisions, nor prevent that party from thereafter
enforcing each and every other provision of this Agreement. The


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<PAGE>   8
rights granted both parties herein are cumulative and shall not constitute a
waiver of either party's right to assert all other legal remedies available to
it under the circumstances.

      15. Successors and Assigns. The Company may assign any of its rights under
this Agreement to single or multiple assignees, and this Agreement shall inure
to the benefit of the successors and assigns of the Company. Subject to the
restrictions on transfer herein set forth, this Agreement shall be binding upon
Purchaser and his or her heirs, executors, administrators, successors and
assigns.

      16. Interpretation. Any dispute regarding the interpretation of this
Agreement shall be submitted by Purchaser or by the Company forthwith to the
Administrator which shall review such dispute at its next regular meeting. The
resolution of such a dispute by the Administrator shall be final and binding on
all parties.

      17. Governing Law; Severability. This Agreement is governed by the
internal substantive laws but not the choice of law rules, of New Jersey.

      18. Entire Agreement. The Plan is incorporated herein by reference. This
Agreement (including the exhibits referenced herein), the Plan, and the
Investment Representation Statement constitute the entire agreement of the
parties with respect to the subject matter hereof and supersede in their
entirety all prior undertakings and agreements of the Company and Purchaser with
respect to the subject matter hereof, and may not be modified adversely to the
Purchaser's interest except by means of a writing signed by the Company and
Purchaser.

      By Purchaser's signature below, Purchaser represents that he or she is
familiar with the terms and provisions of the Plan, and hereby accepts this
Agreement subject to all of the terms and provisions thereof. Purchaser has
reviewed the Plan and this Agreement in their entirety, has had an opportunity
to obtain the advice of counsel prior to executing this Agreement and fully
understands all provisions of this Agreement. Purchaser agrees to accept as
binding, conclusive and final all decisions or interpretations of the
Administrator upon any questions arising under the Plan or this Agreement.
Purchaser further agrees to notify the Company upon any change in the residence
indicated in the Notice of Grant of Stock Purchase Right.

PURCHASER                                OPTIMARK HOLDINGS, INC.


___________________________________      By: ___________________________________
Signature

___________________________________      Title:_________________________________
Print Name


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                                   EXHIBIT A-1

                      ASSIGNMENT SEPARATE FROM CERTIFICATE



      FOR VALUE RECEIVED I, __________________________, hereby sell, assign and
transfer unto _________________________________________________ (__________)
shares of the Common Stock of Optimark Holdings, Inc. standing in my name of
the books of said corporation represented by Certificate No. _____ herewith and
do hereby irrevocably constitute and appoint ______________________________ to
transfer the said stock on the books of the within named corporation with full
power of substitution in the premises.

      This Stock Assignment may be used only in accordance with the Restricted
Stock Purchase Agreement between Optimark Holdings, Inc. and the undersigned
dated ______________, ____.


Dated: _______________, _____       Signature:______________________________























INSTRUCTIONS: Please do not fill in any blanks other than the signature line.
The purpose of this assignment is to enable the Company to exercise its
Repurchase Option as set forth in the Agreement, without requiring additional
signatures on the part of the Purchaser.
<PAGE>   10
                                   EXHIBIT A-2

                            JOINT ESCROW INSTRUCTIONS


                                                      ____________________, __


Corporate Secretary
Optimark Holdings, Inc.
[Address]

Dear ______________________:

      As Escrow Agent for both Optimark Holdings, Inc. (the "Company") and
the undersigned purchaser of stock of the Company (the "Purchaser"), you are
hereby authorized and directed to hold the documents delivered to you pursuant
to the terms of that certain Restricted Stock Purchase Agreement ("Agreement")
between the Company and the undersigned, in accordance with the following
instructions:

      1. In the event the Company and/or any assignee of the Company (referred
to collectively for convenience herein as the "Company") exercises the Company's
repurchase option set forth in the Agreement (the "Repurchase Option"), the
Company shall give to Purchaser and you a written notice specifying the number
of shares of stock to be purchased, the purchase price, and the time for a
closing hereunder at the principal office of the Company. Purchaser and the
Company hereby irrevocably authorize and direct you to close the transaction
contemplated by such notice in accordance with the terms of said notice.

      2. At the closing, you are directed (a) to date the stock assignments
necessary for the transfer in question, (b) to fill in the number of shares
being transferred, and (c) to deliver same, together with the certificate
evidencing the shares of stock to be transferred, to the Company or its
assignee, against the simultaneous delivery to you of the purchase price (by
cash, a check, or some combination thereof) for the number of shares of stock
being purchased pursuant to the exercise of the Company's Repurchase Option.

      3. Purchaser irrevocably authorizes the Company to deposit with you any
certificates evidencing shares of stock to be held by you hereunder and any
additions and substitutions to said shares as defined in the Agreement.
Purchaser does hereby irrevocably constitute and appoint you as Purchaser's
attorney-in-fact and agent for the term of this escrow to execute with respect
to such securities all documents necessary or appropriate to make such
securities negotiable and to complete any transaction herein contemplated,
including but not limited to the filing with any applicable state blue sky
authority of any required applications for consent to, or notice of transfer of,
the securities. Subject to the provisions of this paragraph 3, Purchaser shall
exercise all rights and privileges of a shareholder of the Company while the
stock is held by you.
<PAGE>   11
      4. Upon written request of the Purchaser, but no more than once per
calendar year, unless the Company's Repurchase Option has been exercised, you
will deliver to Purchaser a certificate or certificates representing so many
shares of stock as are not then subject to the Company's Repurchase Option.
Within ninety (90) days after cessation of Purchaser's continuous employment by
or services to the Company, or any parent or subsidiary of the Company, you will
deliver to Purchaser a certificate or certificates representing the aggregate
number of shares held or issued pursuant to the Agreement and not purchased by
the Company or its assignees pursuant to exercise of the Company's Repurchase
Option.

      5. If at the time of termination of this escrow you should have in your
possession any documents, securities, or other property belonging to Purchaser,
you shall deliver all of the same to Purchaser and shall be discharged of all
further obligations hereunder.

      6. Your duties hereunder may be altered, amended, modified or revoked only
by a writing signed by all of the parties hereto.

      7. You shall be obligated only for the performance of such duties as are
specifically set forth herein and may rely and shall be protected in relying or
refraining from acting on any instrument reasonably believed by you to be
genuine and to have been signed or presented by the proper party or parties. You
shall not be personally liable for any act you may do or omit to do hereunder as
Escrow Agent or as attorney-in-fact for Purchaser while acting in good faith,
and any act done or omitted by you pursuant to the advice of your own attorneys
shall be conclusive evidence of such good faith.

      8. You are hereby expressly authorized to disregard any and all warnings
given by any of the parties hereto or by any other person or corporation,
excepting only orders or process of courts of law and are hereby expressly
authorized to comply with and obey orders, judgments or decrees of any court. In
case you obey or comply with any such order, judgment or decree, you shall not
be liable to any of the parties hereto or to any other person, firm or
corporation by reason of such compliance, notwithstanding any such order,
judgment or decree being subsequently reversed, modified, annulled, set aside,
vacated or found to have been entered without jurisdiction.

      9. You shall not be liable in any respect on account of the identity,
authorities or rights of the parties executing or delivering or purporting to
execute or deliver the Agreement or any documents or papers deposited or called
for hereunder.

      10. You shall not be liable for the outlawing of any rights under the
Statute of Limitations with respect to these Joint Escrow Instructions or any
documents deposited with you.

      11. You shall be entitled to employ such legal counsel and other experts
as you may deem necessary properly to advise you in connection with your
obligations hereunder, may rely upon the advice of such counsel, and may pay
such counsel reasonable compensation therefor.


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<PAGE>   12
      12. Your responsibilities as Escrow Agent hereunder shall terminate if you
shall cease to be an officer or agent of the Company or if you shall resign by
written notice to each party. In the event of any such termination, the Company
shall appoint a successor Escrow Agent.

      13. If you reasonably require other or further instruments in connection
with these Joint Escrow Instructions or obligations in respect hereto, the
necessary parties hereto shall join in furnishing such instruments.

      14. It is understood and agreed that should any dispute arise with respect
to the delivery and/or ownership or right of possession of the securities held
by you hereunder, you are authorized and directed to retain in your possession
without liability to anyone all or any part of said securities until such
disputes shall have been settled either by mutual written agreement of the
parties concerned or by a final order, decree or judgment of a court of
competent jurisdiction after the time for appeal has expired and no appeal has
been perfected, but you shall be under no duty whatsoever to institute or defend
any such proceedings.

      15. Any notice required or permitted hereunder shall be given in writing
and shall be deemed effectively given upon personal delivery or upon deposit in
the United States Post Office, by registered or certified mail with postage and
fees prepaid, addressed to each of the other parties thereunto entitled at the
following addresses or at such other addresses as a party may designate by ten
(10) days' advance written notice to each of the other parties hereto.


            COMPANY:          Optimark Holdings, Inc.
                              [Address]


            PURCHASER:        ______________________________

                              ______________________________

                              ______________________________

            ESCROW AGENT:     Corporate Secretary
                              Optimark Holdings, Inc.
                              [Address]

      16. By signing these Joint Escrow Instructions, you become a party hereto
only for the purpose of said Joint Escrow Instructions; you do not become a
party to the Agreement.

      17. This instrument shall be binding upon and inure to the benefit of the
parties hereto, and their respective successors and permitted assigns.

      18. The Restricted Stock Purchase Agreement is incorporated herein by
reference. These Joint Escrow Instructions, the 1999 Stock Plan, and the
Restricted Stock Purchase Agreement (including the exhibits referenced therein)
constitute the entire agreement of the parties with respect


                                      -3-
<PAGE>   13
to the subject matter hereof and supersede in their entirety all prior
undertakings and agreements of the Escrow Agent, the Purchaser and the Company
with respect to the subject matter hereof, and may not be modified except by
means of a writing signed by the Escrow Agent, the Purchaser and the Company.

      19. These Joint Escrow Instructions shall be governed by, and construed
and enforced in accordance with, the laws of the State of New Jersey.

                                          Very truly yours,

                                          OPTIMARK HOLDINGS, INC.

                                          By: __________________________________

                                          Title: _______________________________

                                          PURCHASER:

                                          ______________________________________
                                           (Signature)

                                          ______________________________________
                                           (Typed or Printed Name)



ESCROW AGENT:


___________________________________
Corporate Secretary



                                      -4-
<PAGE>   14
                                   EXHIBIT A-3

                                CONSENT OF SPOUSE

      I, ____________________, spouse of ___________________, have read and
approve the foregoing Restricted Stock Purchase Agreement (the "Agreement"). In
consideration of granting of the right to my spouse to purchase shares of
Optimark Holdings, Inc., as set forth in the Agreement, I hereby appoint my
spouse as my attorney-in-fact in respect to the exercise of any rights under the
Agreement and agree to be bound by the provisions of the Agreement insofar as I
may have any rights in said Agreement or any shares issued pursuant thereto
under the community property laws or similar laws relating to marital property
in effect in the state of our residence as of the date of the signing of the
foregoing Agreement.

Dated: _______________, ______            Signature: ___________________________
<PAGE>   15
                                   EXHIBIT A-4

                          ELECTION UNDER SECTION 83(b)
                      OF THE INTERNAL REVENUE CODE OF 1986

The undersigned taxpayer hereby elects, pursuant to the above-referenced Federal
Tax Code, to include in taxpayer's gross income for the current taxable year,
the amount of any compensation taxable to taxpayer in connection with his
receipt of the property described below:

1.    The name, address, taxpayer identification number and taxable year of the
      undersigned are as follows:

      NAME:                   TAXPAYER:                     SPOUSE:

      ADDRESS:

      IDENTIFICATION NO.:     TAXPAYER:                     SPOUSE:

      TAXABLE YEAR:

2.    The property with respect to which the election is made is described as
      follows:__________ shares (the "Shares") of the Common Stock of Optimark
      Holdings, Inc. (the "Company").

3.    The date on which the property was transferred is:______, ____.

4.    The property is subject to the following restrictions:

      The Shares may be repurchased by the Company, or its assignee, on certain
      events. This right lapses with regard to a portion of the Shares based on
      the continued performance of services by the taxpayer over time.

5.    The fair market value at the time of transfer, determined without regard
      to any restriction other than a restriction which by its terms will never
      lapse, of such property is:

      $_______________

6. The amount (if any) paid for such property is:

      $_______________

The undersigned has submitted a copy of this statement to the person for whom
the services were performed in connection with the undersigned's receipt of the
above-described property. The transferee of such property is the person
performing the services in connection with the transfer of said property.

The undersigned understands that the foregoing election may not be revoked
except with the consent of the Commissioner.

Dated: _______________, ____              _____________________________________
                                          ___________________________, Taxpayer

The undersigned spouse of taxpayer joins in this election.

Dated: _______________, ____              _____________________________________
                                          Spouse of Taxpayer
<PAGE>   16
                                    EXHIBIT B

                       INVESTMENT REPRESENTATION STATEMENT

PURCHASER         :

COMPANY           :     OPTIMARK HOLDINGS, INC.

SECURITY          :     COMMON STOCK

AMOUNT            :

DATE              :

In connection with the purchase of the above-listed Securities, the undersigned
Purchaser represents to the Company the following:

            (a) Purchaser is aware of the Company's business affairs and
financial condition and has acquired sufficient information about the Company to
reach an informed and knowledgeable decision to acquire the Securities.
Purchaser is acquiring these Securities for investment for Purchaser's own
account only and not with a view to, or for resale in connection with, any
"distribution" thereof within the meaning of the Securities Act of 1933, as
amended (the "Securities Act").

            (b) Purchaser acknowledges and understands that the Securities
constitute "restricted securities" under the Securities Act and have not been
registered under the Securities Act in reliance upon a specific exemption
therefrom, which exemption depends upon, among other things, the bona fide
nature of Purchaser's investment intent as expressed herein. In this connection,
Purchaser understands that, in the view of the Securities and Exchange
Commission, the statutory basis for such exemption may be unavailable if
Purchaser's representation was predicated solely upon a present intention to
hold these Securities for the minimum capital gains period specified under tax
statutes, for a deferred sale, for or until an increase or decrease in the
market price of the Securities, or for a period of one (1) year or any other
fixed period in the future. Purchaser further understands that the Securities
must be held indefinitely unless they are subsequently registered under the
Securities Act or an exemption from such registration is available. Purchaser
further acknowledges and understands that the Company is under no obligation to
register the Securities. Purchaser understands that the certificate evidencing
the Securities will be imprinted with a legend which prohibits the transfer of
the Securities unless they are registered or such registration is not required
in the opinion of counsel satisfactory to the Company, and any other legend
required under applicable state securities laws.

            (c) Purchaser is familiar with the provisions of Rule 701 and Rule
144, each promulgated under the Securities Act, which, in substance, permit
limited public resale of "restricted securities" acquired, directly or
indirectly from the issuer thereof, in a non-public offering subject to the
satisfaction of certain conditions. Rule 701 provides that if the issuer
qualifies under Rule 701 at the time of the grant of the Stock Purchase Right to
the Purchaser, the exercise will be exempt from
<PAGE>   17
registration under the Securities Act. In the event the Company becomes subject
to the reporting requirements of Section 13 or 15(d) of the Securities Exchange
Act of 1934, ninety (90) days thereafter (or such longer period as any market
stand-off agreement may require) the Securities exempt under Rule 701 may be
resold, subject to the satisfaction of certain of the conditions specified by
Rule 144, including: (1) the resale being made through a broker in an
unsolicited "broker's transaction" or in transactions directly with a market
maker (as said term is defined under the Securities Exchange Act of 1934); and,
in the case of an affiliate, (2) the availability of certain public information
about the Company, (3) the amount of Securities being sold during any three (3)
month period not exceeding the limitations specified in Rule 144(e), and (4) the
timely filing of a Form 144, if applicable.

      In the event that the Company does not qualify under Rule 701 at the time
of grant of the Stock Purchase Right, then the Securities may be resold in
certain limited circumstances subject to the provisions of Rule 144, which
requires the resale to occur not less than one (1) year after the later of the
date the Securities were sold by the Company or the date the Securities were
sold by an affiliate of the Company, within the meaning of Rule 144; and, in the
case of acquisition of the Securities by an affiliate, or by a non-affiliate who
subsequently holds the Securities less than two (2) years, the satisfaction of
the conditions set forth in sections (1), (2), (3) and (4) of the paragraph
immediately above.

            (d) Purchaser further understands that in the event all of the
applicable requirements of Rule 701 or 144 are not satisfied, registration under
the Securities Act, compliance with Regulation A, or some other registration
exemption will be required; and that, notwithstanding the fact that Rules 144
and 701 are not exclusive, the Staff of the Securities and Exchange Commission
has expressed its opinion that persons proposing to sell private placement
securities other than in a registered offering and otherwise than pursuant to
Rules 144 or 701 will have a substantial burden of proof in establishing that an
exemption from registration is available for such offers or sales, and that such
persons and their respective brokers who participate in such transactions do so
at their own risk. Purchaser understands that no assurances can be given that
any such other registration exemption will be available in such event.

                                          Signature of Purchaser:


                                          ______________________________________

                                          Date:________________, ____


                                      -2-