EXHIBIT 10.1




                              Separation Agreement

April 11, 2002

Mr. Neil G. Cohen
3 Whittier Way
Livingston, NJ  07039

Dear Neil:

This letter confirms your resignation  from employment as an officer,  director,
administrator,  and/or trustee with OptiMark Holdings,  Inc.  ("Holdings"),  its
wholly-owned  subsidiaries,  OptiMark US  Equities,  Inc.  ("US  Equities")  and
OptiMark,  Inc.  ("OI"),  and the  majority  owned  subsidiary  of OI,  OptiMark
Innovations Inc. ("OII" and  collectively,  the "Company"),  effective as of the
Effective Date (as hereinafter  defined).  This agreement (the "Agreement") sets
forth the entire agreement between the Company and you regarding the termination
of your  employment.  Reference  is made to that certain  employment  agreement,
dated June 3, 1999, by and between  Holdings and you, as amended by that certain
amendment,  dated June 19, 2001,  by and between OI and you  (collectively,  the
"Employment Agreement").

The Company recognizes that without all of the benefits conferred to you under
this Agreement, you would have terminated employment sooner than the Company
otherwise would have wanted, without rights to the Benefits (as hereinafter
defined).

In view of the foregoing, the parties hereto agree as follows:

1.   OBLIGATIONS.

     A.    Effective Date.  The  effective  date  of  your resignation  from the
     Company (the "Effective Date") will be the close of business on the date of
     the earliest to occur of:

          (i)  Friday, May 31, 2002;


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          (ii)  your termination for "Cause" (as hereinafter defined);

          (iii) your death or "Disability" (as hereinafter defined);

          (iv)  an "Event of Default" (as defined in the Bridge Loan Agreement)
          under Section 8.1(g) of that certain Loan Agreement, dated March 21,
          2002 (the "Bridge Loan Agreement"), by and among Holdings, SOFTBANK
          Capital Partners LP, SOFTBANK Capital Advisors Fund LP and SOFTBANK
          Capital LP; and

          (v)   completion to the reasonable satisfaction of the board of
          directors of Holdings, of each of the tasks set forth on Exhibit A
          hereto.


     For purposes hereof, (i) "Cause" shall mean (I) fraud, dishonesty, gross
     negligence, breach of fiduciary duty, or malfeasance by you in connection
     with the performance of your duties under the Employment Agreement and
     which results in material harm to the Company as determined by the board of
     directors of the Company, or (II) your conviction of a felony or crime
     involving moral turpitude and (ii) "Disability" shall mean your physical or
     mental inability to render services in connection with your employment for
     thirty (30) consecutive days from the date of this Agreement.

     B.   Salary; Benefits. Until the Effective Date, you shall continue
     employment with the Company pursuant to the terms of the Employment
     Agreement and shall be entitled to all rights and subject to all
     obligations thereunder.

2.   PAYMENT.  On the date first written above (the "Execution Date"), you will
be immediately entitled to the following (collectively, the "Benefits"):

     A.   Salary. You shall receive an amount in cash equal to your salary from
     the Execution Date through May 31, 2002, less applicable withholding or
     other amounts in respect of taxes and 401(k) contributions that you have
     elected.

     B.   Stay-on Bonus. You shall receive a stay-on bonus payment of fifty
     thousand dollars ($50,000) cash, less applicable withholding or other
     amounts in respect of taxes and 401(k) contributions that you have elected.

     C.   Accrued but Unused Vacation. You shall receive a cash payment
     reflecting 100 hours of your accrued but unused vacation


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                                                                               3

     time as of the date of this Agreement less applicable withholding or other
     amounts in respect of taxes and 401(k) contributions that you have elected.

     D.   Medical Benefits. So long as you are not terminated for Cause,
     commencing on the Effective Date and continuing through August 31, 2002,
     the Company shall pay all premiums, excluding customary co-payment amounts,
     in connection with standard COBRA coverage benefits that will be made
     available to you; provided, however, that in the event that you commence
     employment elsewhere with coverage under a medical insurance plan prior to
     August 31, 2002, then the Company's payment obligations in respect of COBRA
     shall immediately cease and you shall be obligated to return any premium
     amounts paid by the Company for periods covered by the medical insurance
     plan of such subsequent employer.

     E.   Options. So long as you are not terminated for Cause, options to
     purchase 120,250 shares of Series F Preferred Stock, par value $.01 per
     share, of Holdings (the "Series F Preferred Stock") previously granted to
     you pursuant to that certain Stock Option Agreement dated November 14, 2001
     (the "Stock Option Agreement"), shall automatically vest and such options
     (the "Accelerated Options"), together with existing options to purchase
     18,500 shares of Series F Preferred Stock currently exercisable by you (the
     "Vested Options"), shall be exercisable by you for a period of thirty-six
     (36) months from the Effective Date. In the event that you are terminated
     for Cause, then you shall have no rights to the Accelerated Options (except
     Accrued Options (as hereinafter defined)) and your rights to the Vested
     Options and any other options to purchase Series F Preferred Stock that
     vest prior to the Effective Date (the "Accrued Options"), shall be governed
     by Section 1 of the Stock Option Agreement (i.e., the Vested Options and
     Accrued Options shall be exercisable for ninety (90) days from the
     Effective Date).

     F.   Laptop Computer and Cellular Telephone. So long as you are not
     terminated for Cause, you shall receive all right, title and interest in
     (i) that certain IBM Thinkpad laptop computer (Type 2645-51U, serial number
     78-CN147), excluding any proprietary Company software, third party software
     licensed to the Company and all files, Company electronic mail messages, or
     other Confidential Information (as hereinafter defined) copied or residing
     on or in the hard drive and (ii) that certain Nokia model 3390 cellular
     telephone; provided, however, that your cellular telephone shall be
     disconnected from any Company calling plan as of the Effective Date and you
     shall have sole


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                                                                               4


     responsibility to subscribe and make all payments for cellular telephone
     service thereafter.

     G.   Reasonable Fees of Counsel. Upon (i) execution of this Agreement by
     the parties and (ii) your presentment of an itemized bill for time and
     disbursements, the Company shall reimburse you for fees of counsel in
     connection with the negotiation of this Agreement, such fees not to exceed
     two thousand five hundred dollars ($2,500.00).

The amounts owed in respect of the Benefits described in paragraphs 2(A), 2(B) ,
2(C), and 2(G) shall be made within one (1) business day of the execution of
this Agreement and shall be made by wire transfer to the account on file with
the Company to which your salary has been deposited to directly by the Company.

In the event that you are terminated for Cause, then you shall repay to the
Company the net amount that you received under paragraph 2B hereof.

The sums and Benefits being paid to or provided to you pursuant to this
paragraph 2 are in lieu of any other payment, obligation, distribution, salary,
bonus, incentive plan payment, severance pay, unused accrued vacation pay or any
other form of compensation, benefit or damages of any kind otherwise due, owing
or payable by the Company to you. You and the Company also acknowledge and agree
that, except as detailed in written expense reports that you have submitted or
will submit to the Company on or before the Effective Date, or as expressly set
forth in this Agreement, no other monetary or other payments or other
consideration or benefits are due to you from the Company, whether or not
pursuant to any employment agreement between the Company and you.

3.   Non-Solicitation; Non-Disclosure; Assignment of Inventions.

     A.   Non-Solicitation. From the Effective Date and during the period of
     eighteen (18) months from the Effective Date, you agree that you will not,
     directly or indirectly, as an equity owner, director, employee, consultant,
     lender, agent or in any other capacity, (i) solicit, induce or entice for
     employment, retention or affiliation, or recommend to any corporation,
     entity or other person the solicitation, inducement or enticement for
     employment, retention or affiliation of, any employee, consultant,
     independent contractor or other person employed or retained by, or
     affiliated with, the Company, or any of its affiliates or (ii) engage in
     any activity intended to terminate, disrupt or interfere with the Company's
     or


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                                                                               5

     any of its affiliate's relationship with a customer, supplier, lessor or
     other person.

     B.   Non-Disclosure. You hereby acknowledge and agree that during the
     period of your employment with the Company you were in a confidential
     relationship with the Company and have had access to confidential
     information and trade secrets of the Company and its affiliates
     (collectively, the "Confidential Information"). Confidential Information
     includes, but is not limited to, all confidential or any proprietary
     information regarding the Company and its affiliates or any aspect of their
     respective business or operations, including, but not limited to, customer
     and client lists, financial information, price lists, pricing strategies,
     marketing and sales strategies and procedures, computer programs, databases
     and software, supplier, vendor and service information, personnel
     information, operating procedures and techniques, business plans and
     strategies, terms of products strategic alliances (both those in existence
     and those contemplated), operational techniques, intellectual property
     strategies, the status of the Company's intellectual property, quality
     control procedures and systems, internal control procedures, accounting and
     reporting systems, special projects, employee compensation, personnel, and
     all other records, files, and information in respect of the Company. You
     shall use reasonable measures to maintain the confidentiality of all
     Confidential Information and shall not use or permit the use of, or
     disclose, discuss, communicate or transmit or permit the disclosure,
     discussion, communication or transmission of, any Confidential Information
     except with the express written permission of the Company. This paragraph
     3B shall not apply to (i) information that, by means other than your
     deliberate or inadvertent disclosure, becomes generally known to the
     public, or (ii) information the disclosure of which is compelled by law
     (including judicial or administrative proceedings and legal process). In
     that connection, in the event that you are requested or required (by oral
     question, interrogatories, requests for information or documents,
     subpoenas, civil investigative demand or other legal process) to disclose
     any Confidential Information, you agree to provide the Company with prompt
     written notice of such request or requirement so that the Company may seek
     an appropriate protective order or relief therefrom or may waive the
     requirements of this paragraph 3B. If, failing the entry of a protective
     order or the receipt of a waiver hereunder, you are, in the opinion of
     counsel, compelled to disclose Confidential Information under pain of
     liability for contempt or other censure or penalty, you may disclose such
     Confidential Information to the extent so required. In the event of a
     breach or threatened breach by you of any of the provisions of this
     paragraph 3, the


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     Company shall be entitled to an injunction to be issued by any court or
     tribunal of competent jurisdiction to restrain you from committing or
     continuing any such violation. In any proceeding for an injunction, you
     agree that your ability to answer in damages, or your or the Company's
     ability to take any other lawful remedial action, shall not be a bar or be
     interposed as a defense to the granting of a temporary or permanent
     injunction against you. You acknowledge that the Company will not have an
     adequate remedy at law in the event of any breach by you as aforesaid and
     that the Company may suffer irreparable damage and injury in the event of
     such a breach by you. Nothing contained herein shall be construed as
     prohibiting the Company from pursuing any other remedy or remedies
     available to the Company in respect of such breach or threatened breach.

     C.   Assignment of Inventions. With respect to Intellectual Property (as
     hereinafter defined) made or conceived by you (either solely or jointly
     with another or others) during your employment by the Company and which
     Intellectual Property is in any way based on or related to your work for or
     on behalf of the Company or otherwise result from work performed for or at
     the request of the Company:

          (i) you shall promptly and fully inform the Company of each such item
          of Intellectual Property in writing, setting forth in detail the
          procedures employed and the results achieved;

          (ii) you shall apply, at the Company's request and expense, or at the
          request and expense of such other person or entity as the Company
          shall designate, for United States and foreign patents or copyrights
          or other form of protection either in the Company's name or otherwise
          as the Company or its designee shall desire;

          (iii) you agree to and hereby do assign to the Company or such other
          person or entity as the Company shall designate all of your rights to
          such Intellectual Property, including but not limited to applications
          for United States and/or foreign patents or copyrights, and United
          States and/or foreign patents or copyrights granted upon such
          Intellectual Property; and

          (iv) you shall execute and deliver promptly to the Company or its
          designee (without charge but at the Company's or its designee's
          expense) such written instruments, and do such other acts, such as
          giving testimony in support of inventorship, authorship or
          contribution, as may be reasonably necessary in the opinion of the
          Company to obtain and maintain United


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                                                                               7

          States and/or foreign patents or copyright or other protection and to
          vest the entire right and title of same in the Company or its
          designee.

     As used herein, "Intellectual Property" means inventions, discoveries,
     concepts and ideas, whether or not patentable, copyrightable,
     trademarkable, protectable as a mask work, or protectable as a trade secret
     including, but not limited to any process, method, formula, article,
     composition, device, product, tool, machine, computer program, source code,
     object code, apparatus, appliance, design, drawing, practice, manufacture
     or technique, as well as any improvements thereto and know-how related
     thereto.

     To the extent possible, any Intellectual Property made or conceived by you
     shall be deemed a "work made for hire" within the meaning of ss. 101 of the
     Federal Copyright Act, as amended.

     D. It is expressly acknowledged and agreed by you that your obligations set
     forth in this paragraph 3 were an inducement to the Company to enter into
     this Agreement and that the scope of the provisions set forth in this
     paragraph 3 are in each case reasonable and necessary in light of the
     circumstances. If, for any reason, any aspect of any of the provisions set
     forth in this paragraph 3 as they apply to you is determined by a court of
     competent jurisdiction to be unreasonable, illegal, invalid or
     unenforceable, the provisions shall, to the fullest extent possible, be
     modified by the court to the minimum extent required by applicable law in
     order to make the provisions legal, valid and enforceable to the fullest
     extent permitted by applicable law. You hereby acknowledge and agree that
     your services were and continue to be of a unique character and you
     expressly grant the Company the right to enforce the provisions of this
     paragraph 3 through the use of all remedies available at law or in equity,
     including, but not limited to, obtaining a court order, injunction or other
     equitable relief prohibiting you from threatening to breach, breaching or
     continuing to breach any provision of this paragraph 3, without the Company
     being required to post a bond or other security or prove any amount of
     actual damages. If you are adjudicated by a court of competent jurisdiction
     to have violated any of the provisions of this paragraph 3, the Company
     shall be excused and discharged from any obligation to make payments to you
     pursuant to paragraph 2 hereof for the period commencing from the date of
     the violations.

4.   FURTHER OBLIGATIONS. On the Effective Date, you hereby agree to return to
the Company your keys to the Company office, photo


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identification and all Company office equipment and property possessed by you,
except for the items set forth in paragraph 2E above.

5.   RELEASE. In consideration of the Benefits and the other transactions
contemplated herein, for which there was no prior existing obligation, you, for
yourself and your relatives, heirs, executors, administrators, personal
representatives, agents, and affiliates, as the case may be, hereby release and
forever discharge the Company and their respective officers, directors,
employees, shareholders, partners, agents, affiliates, successors and assigns,
and their respective heirs, executors, administrators, personal representatives,
agents, affiliates, successors and assigns, as the case may be (collectively,
"Released Parties"), from any and all obligations, actions, causes of action,
suits, debts, liabilities, damages, guarantees, judgments, claims and demands
whatsoever, whether known or unknown, fixed or contingent, and whether in
administrative proceeding, in arbitration, in law or in equity, other than any
claim to enforce your rights pursuant to this Agreement, (collectively, the
"Claims"), that you ever had, now have, or hereinafter may have against such
Released Parties, as the case may be, by reason of any matter, cause or thing
whatsoever, including, without limitation, Claims arising under, or in any way
related to or connected with: (i) your Employment Agreement and your activities
in connection therewith; (ii) all claims to profit participation, dividends,
distributions, allocations or other equity or ownership interests in the
Company; (iii) any federal, state or local civil or human rights law or any
other local, state or federal law, regulation or ordinance prohibiting, among
other things, sexual harassment or discrimination on the basis of sex, race,
color, creed, religion, age, disability, national origin, sexual orientation or
marital status; (iv) any public policy, contract, tort, or other common law
claim or cause of action, including but not limited to breach of implied or
express contract, intentional or negligent infliction of emotional distress,
negligent misrepresentation, defamation, wrongful discharge; (v) any claim or
cause of action for commission, back wages or other compensation, including, but
not limited to, commissions, back wages or compensation, related to or arising
out of any payments or sums the Company has received or may receive in the
future from any source at any time; (vi) any claim or allegation for costs,
fees, or other expenses, including attorneys' fees, incurred in any matter or
proceeding, except for the attorneys' fees provided for in paragraph 2(G) above.

6.   REPRESENTATIONS AND WARRANTIES. Each party hereto represents and warrants
to the other party hereto that it has had a full and fair opportunity to seek
the advice of legal counsel prior to signing this Agreement and that the parties
hereto cannot now or in the future assert that any party had superior bargaining
power over the other, as


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each party has had a full and fair opportunity to ascertain their respective
rights and responsibilities hereunder. By signing and returning this Agreement,
you acknowledge that you:

          (a) have had sufficient time to review and consider its terms;

          (b) have carefully read and fully understand the terms of this
          Agreement;

          (c) are entering into this Agreement voluntarily and knowing that you
          are releasing Claims that you have or may have against the Company;

          (d) have not assigned any Claims that your have or may have against
          the Company to any third party;

          (e) have had a reasonable opportunity to seek advice from an attorney
          of your choosing prior to signing this Agreement; and

          (f) release all claims, whether known or unknown, that arise up to and
          including the date of execution of this agreement in return for the
          Benefits.

7.   INTEGRATION; WAIVER. This Agreement constitutes the entire agreement and
understanding among the parties and, except as expressly provided herein,
supersedes, terminates and cancels any prior written or oral, express or implied
agreements, understandings, arrangements, covenants, communications,
negotiations, commitments and representations or warranties by any party hereto
or any director, officer, employee, agent, partner or affiliate of any party
hereto. This Agreement is not being executed by the parties hereto in reliance
upon any representation or warranty not expressly set forth herein. Subject to
paragraph 5, this Agreement is intended solely for the benefit of the parties
hereto. Subject to paragraph 5, neither this Agreement nor any of the
relationships or transactions contemplated hereby shall be deemed to create or
enlarge any rights in any parties not a party hereto, under any third-party
beneficiary theory or otherwise. Except as otherwise set forth herein, no
waiver, amendment, modification or cancellation of any term or condition hereof
shall be effective unless executed in writing by the party charged therewith. No
written waiver shall excuse the performance of any act other than those
specifically referred to therein. The waiver by any party hereto of a breach of
any provision of this Agreement by any other party hereto shall not operate or
be construed as a waiver of any other breach or provision of this Agreement.


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8.   NO DISPARAGING STATEMENTS. Each party to this Agreement agrees to refrain
from making any disparaging statements, either orally or in writing, about the
other party or, in the case of the Company, about any of the Company's
directors, officers, employees, agents or representatives.

9.   CONSULTING. You acknowledge and agree that the Company may, from time to
time and on terms and conditions mutually acceptable to the parties, engage you
to provide consulting services to the Company on legal matters, including,
without limitation, matters related to the intellectual property rights and
obligations of the Company.

10.  CONFIDENTIALITY. Except for communicating with legal or financial advisors,
and except as otherwise may be required by applicable law, the parties will keep
confidential the terms and conditions of this Agreement.

11.  SEVERABILITY. If any term or terms of this Agreement are declared invalid
by any court of competent jurisdiction, the Agreement shall be deemed amended by
excluding the invalid term or terms, and all remaining terms shall continue in
full force and effect. You agree to execute such amendments as may be necessary
to accomplish the intent of this provision, which is to maintain in force all
terms of this Agreement to the full extent permitted by law.

12.  GOVERNING LAW. This Agreement shall be governed by, construed, and enforced
in accordance with the laws of the State of New Jersey, without regard to the
conflicts of laws principles thereof.

13.  WAIVER OF JURY TRIAL. To the extent not prohibited by applicable law which
cannot be waived, each of the parties hereto hereby waives and covenants that it
will not assert (whether as plaintiff, defendant or otherwise), any right to
trial by jury in any forum in respect of any issue or action, claim, cause of
action or suit (in contract, tort, equity, or otherwise), inquiry, proceeding or
investigation arising out of or based upon this Agreement or the subject matter
hereof or in any way connected with or related or incidental to the transactions
contemplated hereby, in each case whether now existing or hereafter arising,
except for issues, actions, claims, causes of action or suits, inquiries,
proceedings or investigations arising out of or based solely upon your alleged
gross negligence or willful misconduct. Any party hereto may file an original
counterpart or a copy of this paragraph 13 with any court as written evidence of
the consent of each such party to the waiver of its right to trial by jury.

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Please review this Agreement carefully. If you have any questions about any of
the information contained in this Agreement, please call me at (201) 536-7121.

                                               Sincerely,

                                               OPTIMARK HOLDINGS, INC.


                                               /s/Robert J. Warshaw
                                               ---------------------------
                                               By:    Robert J. Warshaw
                                               Title: Chief Executive Officer

ACCEPTED AND AGREED:


/s/Neil G. Cohen
------------------------------
Name:  Neil G. Cohen
Date:  April 12, 2002



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                                                                       Exhibit A
                                                                       ---------

                              Section 1(A)(v) Tasks
                              ---------------------

         (a) the closing of the transactions contemplated by that certain
Securities Purchase Agreement, dated February 4, 2002, as amended by that
certain Amendment dated March 6, 2002, by and between OII and The Ashton
Technology Group, Inc.; and

         (b) the closing of the transactions contemplated by that certain
non-binding term sheet for the investment of $10,000,000 of cash by Draper
Fisher Jurvetson ePlanet in OII; and

         (c) the filing with the Securities and Exchange Commission ("SEC") of
the Annual Report on Form 10-K of Holdings for the period ended December 31,
2001; and

         (d) the (I) acceptance by the SEC of the filing of the definitive proxy
statement of Holdings pursuant to Section 14(a) of the Securities Exchange Act
of 1934, as amended and (II) mailing of materials to shareholders of record in
connection with the 2002 annual meeting of stockholders of Holdings; and

         (e) the closing of the transactions contemplated by the Bridge Loan
Agreement; and

         (f) execution and closing of definitive settlement agreements, on terms
and conditions acceptable to the board of directors of the Company, covering all
matters arising in connection with (I) Finova Capital Corporation v. OptiMark
Technologies, Inc., OptiMark, Inc. and OptiMark Holdings, Inc., filed June 15,
2001 in the Superior Court of New Jersey - Hudson County, and (II) Comdisco,
Inc. v. OptiMark Technologies, Inc. (now known as OptiMark US Equities, Inc. and
Avnet, Inc., filed December 15, 2000 in the Superior Court of the State of
Connecticut, Judicial District of Fairfield at Bridgeport; and

         (g) the written submission of a transition plan covering (I) procedures
for accessing and engaging outside counsel to provide legal advice related to
routine legal issues and inquiries, including, without limitation, shareholder
inquiries, stock transfer requests, vendor inquiries, and intellectual property
portfolio management, and (II) the engagement of outside counsel for the purpose
of resolving creditor issues and providing legal advice related to bankruptcy
issues.