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                                                                  EXHIBIT 10.13

[OPTIMARK TECHNOLOGIES, INC. LOGO]     10 Exchange Place, Jersey City, NJ 07302
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BY E-MAIL AND TELEFACSIMILE


PRIVATE & CONFIDENTIAL


November 15, 1999

William F. Adiletta
66 Petty Road
Cranbury, New Jersey  08512

Re:      Separation Agreement and General Release

Dear Bill:

This letter (the "Letter Agreement") confirms the termination of your
employment as Executive Vice President of OptiMark Technologies, Inc.
("OptiMark") and as President of the NASDAQ Business Division of OptiMark,
effective immediately. By signing this Letter Agreement, you agree to the
following terms and conditions:

        A. Subject to the provisions of this Letter Agreement, OptiMark will
provide you with the following separation payments and benefits:

        1. OptiMark will pay you as severance the amount of $450,000.00,
           minus the deductions required by law, which represents the sum
           of (a) twelve (12) months of your current base salary, (b) all
           bonuses you received during the preceding twelve (12) month
           period, and (c) $25,000 (collectively, the "Severance
           Payment"). The Severance Payment will be paid to you according
           to the following schedule:

           (a) One-third of the Severance Payment will be paid to
               you within three (3) business days of the date that
               this Letter Agreement becomes effective in accordance
               with its terms;

           (b) One-third of the Severance Payment will be paid to you on the
               first business day following January 1, 2000; and

           (c) The final one-third of the Severance Payment will be paid to you
               in equal semi-monthly installments, by keeping you on OptiMark's
               payroll for a period of six (6) months, from January 1, 2000
               through June 30, 2000 (the "Severance Period").

Your coverage, and the coverage of your eligible dependents, under OptiMark's
group health plan will continue during the Severance Period with OptiMark and
you making the same percentage of contributions as each did as of November 8,
1999. Thereafter, you may continue your coverage as part of your entitlement
under the Consolidated Omnibus Budget Reconciliation Act of 1985 ("COBRA").
(See reference to COBRA in paragraph C.2, below.)


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2.    Subject to your continued compliance with the terms and
      conditions of this Letter Agreement, fifty percent (50%) of
      any options granted to you pursuant to OptiMark's Incentive
      Stock Agreement and OptiMark's Non-Qualified Stock Option
      Agreement which were scheduled to vest after November 1, 1999
      shall be treated as vested on the date hereof as if you had
      remained in OptiMark's employ. In addition, you will have
      until November 1, 2002, to exercise all vested options,
      including those otherwise unvested options considered vested
      per the preceding sentence.

3.    You will be provided with a Letter of Reference that is
      mutually satisfactory to you and OptiMark, which shall
      indicate that the termination of your employment was due to
      your voluntary resignation.

4.    Except as provided in paragraph C.1 below, the separation
      payments and benefits described in this Section A represent
      the total amount that will be paid to you and are in lieu of
      any rights to other payments or benefits which you might have
      been eligible to receive as an employee of OptiMark. If you
      breach any of the terms of this Letter Agreement, OptiMark
      will cease making any payments or providing any benefits
      recited herein.

5.    You will have the option of purchasing any OptiMark equipment
      currently in your possession at a price which is reflective of
      OptiMark's book value and which shall be determined in
      OptiMark's sole discretion.

B.    IN CONSIDERATION OF OPTIMARK'S PROVIDING THOSE SEPARATION PAYMENTS AND
BENEFITS DESCRIBED IN SECTION A ABOVE, TO WHICH YOU ARE NOT OTHERWISE ENTITLED,
YOU VOLUNTARILY AGREE TO THE FOLLOWING:

1.    You will sign the General Release attached hereto as Exhibit 1.

2.    You will tender your written resignation from all positions
      you hold with OptiMark or any of its affiliates, which shall
      include your resignation from all Boards of Directors of which
      you are a member and your surrender of all official titles.

3.    You will return to Felice Schulaner all records and materials
      you have in your possession, custody or control that are the
      property of OptiMark no later than November 30, 1999, except
      for property that you have elected to purchase in accordance
      with Section A.6 above.

4.    You will comply with all of the terms and conditions of the
      Employee Agreement (Version II) that you executed on or about
      July 16, 1997, which is incorporated herein and made a part of
      this Letter Agreement; provided, however, that you may hire or
      otherwise retain the services of any former employee of
      OptiMark whose employment was involuntarily terminated by
      OptiMark, subject to your and such former employee's continued
      compliance with all applicable restrictions contained in the
      Employee Agreement (Version II) or any similar agreement which
      the former employee may have signed.

5.    You will not disclose the contents or substance of this Letter
      Agreement or the General Release to anyone except your
      immediate family and any tax, or legal counsel you have


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      consulted regarding the meaning or effect hereof, and you will
      instruct each of the foregoing not to disclose the same.

6.    You will not make any disparaging remarks about OptiMark, or
      any of its present and former directors, officers, agents,
      representatives or employees, to any third parties in a
      business context, including current and potential clients of
      OptiMark. Similarly, OptiMark, in its corporate capacity, will
      not make disparaging remarks about you to any third parties in
      a business context, including current and potential clients of
      OptiMark.

7.    You agree to make yourself reasonably available to OptiMark
      and its representatives in connection with the prosecution and
      defense of any legal proceedings involving matters of which
      you may have relevant knowledge. OptiMark will reimburse you
      for such reasonable expenses as you may incur in providing
      such assistance upon your submission of appropriate
      documentation.

8.    Any dispute arising under this Letter Agreement shall be
      resolved through arbitration sponsored by, and in accordance
      with the rules of, the American Arbitration Association, with
      proceedings conducted by a panel of three arbitrators in
      Newark, New Jersey. In any such proceeding, the arbitration
      panel may award costs and expenses (including reasonable
      attorneys' fees) to the prevailing party. Notwithstanding the
      foregoing, OptiMark shall remain entitled to apply to a court
      of competent jurisdiction to obtain injunctive or other
      equitable relief in the event of your alleged violation of
      Section B.4 above, which shall be in addition to any other
      remedies that may be available to OptiMark.

C.    This Letter Agreement does not affect your entitlement to previously
accrued or vested benefits, which are summarized as follows:

1.    You acknowledge that on November 11, 1999, you were paid the
      sum of $36,778.14, minus applicable withholdings, representing
      all vacation accrued but unused as of November 8, 1999.

2.    Your coverage under OptiMark's group health plan will cease at
      the end of the Severance Period. You will be given separate
      information regarding your right to continue your coverage, as
      required by COBRA.

3.    Your participation in OptiMark's 401k Plan will terminate on
      November 30, 1999. Your rights under these plans will be
      determined by law and in accordance with the terms of the
      plan. A statement of your benefits under the plans will be
      provided to you separately.

By entering into this Letter Agreement, OptiMark does not admit, and
specifically denies, any liability, wrongdoing or violation of any law, statute,
regulation or policy, and it is expressly understood and agreed that this Letter
Agreement is being entered into solely for the purpose of amicably resolving all
matters in controversy of any kind whatsoever concerning your employment and the
termination of your employment. Moreover, by signing this Letter Agreement you
acknowledge that you are not currently aware of any wrongdoing on the part of
OptiMark.

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Because by signing this Letter Agreement and the General Release you are
releasing OptiMark from all claims you might have and you are acknowledging that
no other payments or benefits are due and owing to you, you should review both
documents carefully before signing them. You can take up to twenty-one (21) days
from your receipt of this Letter Agreement to consider its meaning and effect
and to determine whether or not you wish to enter into it. During that time, you
are advised to consult with an attorney.

To receive your separation payments and other benefits, you must sign and return
this Letter Agreement and the General Release no later than twenty-one (21) days
after receiving them. In addition, you may take up to seven (7) days after
executing both documents to revoke your signature. No payments will be made
until the revocation period has expired without your revocation. Any revocation
is requested to be in writing and delivered to OptiMark by hand and marked
"Attention: Felice Schulaner."

THE PAYMENTS AND BENEFITS DESCRIBED IN SECTION A ARE BEING OFFERED FOR THE
PURPOSE OF RESOLVING ALL MATTERS IN DISPUTE BETWEEN YOU AND OPTIMARK WITHOUT
LITIGATION. IF YOU CHOOSE NOT TO SIGN THIS LETTER AGREEMENT AND THE GENERAL
RELEASE, YOU WILL BE PAID THE AMOUNT DUE TO YOU PURSUANT TO THE EMPLOYEE
AGREEMENT (VERSION II) IN EXCHANGE FOR YOUR COMPLIANCE WITH THE TERMS AND
CONDITIONS THEREOF, BUT NO OTHER PAYMENTS OR BENEFITS WILL BE MADE OR PROVIDED
TO YOU. THE REMAINING PAYMENTS AND BENEFITS OFFERED TO YOU, HAVING BEEN OFFERED
ON THE CONDITIONS STATED, MAY NOT BE ENTERED INTO EVIDENCE OR OTHERWISE USED
AGAINST OPTIMARK IN ANY LITIGATION.

This Letter Agreement and the General Release contain the entire agreement
between the parties concerning the subject matter hereof and supersede all
prior agreements, understandings, discussions, negotiations and undertakings,
whether written or oral, express or implied, between the parties with respect
hereto. No representations, inducements, promises or agreements not embodied
herein shall be of any force or effect. This Letter Agreement and the General
Release will be construed in accordance with and governed by the State and
Federal laws applicable in New Jersey. Neither document may be changed or
altered, except in writing signed by OptiMark and you. If any clause of this
Letter Agreement or the General Release is determined to be unenforceable, it
is agreed that this will not affect the enforceability of any other clause or
the remainder of either document.

If you have any questions about your separation benefits, please contact Felice
Schulaner at 201-536-7111.

Very truly yours,



/s/  Phillip Riese
Chief Executive Officer


Agreed to and Accepted By:



/s/  William F. Adiletta

Date:  November 15, 1999


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                                 GENERAL RELEASE
                                       BY
                               WILLIAM F. ADILETTA

         I, WILLIAM F. ADILETTA, in consideration of and subject to the terms
and conditions set out in the letter ("Letter Agreement") to which this General
Release is attached, and other good and valuable consideration, do hereby
release and forever discharge OPTIMARK TECHNOLOGIES, INC. ("OptiMark") and all
of its offices, branches, parents, subsidiaries and affiliates and its present
and former directors, officers, agents, representatives, employees, successors
and assigns, from any and all actions, causes of action, covenants, contracts,
claims and demands whatsoever, which I ever had, now have or which my heirs,
executors, administrators and assigns, or any of them hereafter can, shall or
may have by reason of my employment with or severance of my employment from
OptiMark on or about the 8th day of November, 1999.

         By signing this General Release, I am providing a complete waiver of
all rights and claims that may have arisen, whether known or unknown, up until
the time this General Release is signed. This includes, but is not limited to,
claims based on Title VII of the Civil Rights Act of 1964, the Civil Rights Act
of 1866, the Age Discrimination in Employment Act of 1967 (including the Older
Workers Benefit Protection Act), the Americans with Disabilities Act, the Fair
Labor Standards Act, the Equal Pay Act, the Family and Medical Leave Act, the
Employee Retirement Income Security Act of 1974, the New Jersey Law Against
Discrimination, the New Jersey Labor Laws or any common law, public policy,
contract (whether oral or written, express or implied) or tort law, and any
other local, state or federal law, regulation or ordinance having any bearing
whatsoever on the terms and conditions of my employment and the cessation
thereof. However, I am not releasing any claims I may have that OptiMark
breached the Letter Agreement to which this General Release is attached.

         In addition to waiving my right to file any charge or complaint on my
own behalf, I am waiving my right to participate in any charge or complaint
which may be made by any other person or organization on my behalf before any
federal, state or local court or administrative agency against OptiMark, except
as such waiver is prohibited by law and except to the extent that such
participation is ordered by subpoena or by a court of competent jurisdiction.
Should any charge be filed, I agree that I will not accept any relief or
recovery therefrom.

         I hereby represent that neither I nor anyone acting on my behalf has
filed or will file any action, complaint, charge, grievance or arbitration or
commenced any proceeding, administrative or judicial, against OptiMark or any of
its past or present offices, branches, parents, subsidiaries and affiliates or
its past or present directors, officers, agents, representatives, employees,
successors or assigns.

         I have been given twenty-one (21) days to review the Letter Agreement
and this General Release and to consult with legal counsel, and I am signing
this General Release knowingly, voluntarily and with full understanding of its
terms and effects, and I voluntarily accept the amounts provided for in the
Letter Agreement for the purpose of making full and final settlement of all
claims referred to above. I also understand that this General Release will not
become effective if I revoke my signature within seven (7) days of execution.

         The Letter Agreement and this General Release will be governed by and
construed in accordance with the State and Federal laws applicable in the State
of New Jersey. If any provision in the Letter Agreement or this General Release
is held invalid or unenforceable for any reason, the


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remaining provisions shall be construed as if the invalid or unenforceable
provision had not been included.

In witness hereof, I have executed this General Release this 15th day of
November, 1999.


/s/  William F. Adiletta


State of New York      )
                       ) ss.:
County of New York     )


On this 15th day of November, 1999, before me, a Notary Public of the State of
New York, personally appeared William F. Adiletta to me known and known to me
to be the person described and who executed the foregoing Letter Agreement and
General Release and did then and there acknowledge to me that he voluntarily
executed the same.



/s/  Muriel B. Finkelstein
Notary Public, State of New York
No. 31-4735274
Qualified in New York County
Commission Expires April 30, 2001