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                                                                   EXHIBIT 10.10

                          OPTIMARK TECHNOLOGIES, INC.

                              EMPLOYMENT AGREEMENT

         This Agreement is entered into by and between OptiMark Technologies,
Inc., a Delaware corporation (the "Company") and Phillip J. Riese (the
"Employee").

         WHEREAS, the Company desires to employ the Employee on a full-time
basis in the capacity of Chief Executive Officer of the Company, and the
Employee desires to accept such employment; and

         WHEREAS the parties desire and agree to enter into an employment
relationship by means of this Agreement;

         NOW THEREFORE in consideration of the promises and mutual covenants
herein contained, and other good and valuable consideration, the receipt and
sufficiency of which is hereby acknowledged, it is mutually covenanted and
agreed by the parties as follows:

         1.      POSITION AND DUTIES.  The Employee shall be employed as Chief
Executive Officer of the Company, reporting solely to the Company's Board of
Directors (the "Board") and assuming and discharging such duties and
responsibilities as are commensurate with the Employee's position.  In
performing his basic duties, the Employee shall work at the Company's business
offices located in New York, New York, although the Employee acknowledges that
frequent travel may be necessary in carrying out his duties hereunder.  The
Employee shall perform his duties faithfully and to the best of his ability and
shall devote his full business time and effort (except for permitted vacation
periods and periods of illness and other incapacity) to the performance of his
duties hereunder.  The Employee shall commence employment with the Company
effective November 1, 1998 (the "Effective Date"), and for so long as the
Employee remains Chief Executive Officer of the Company, the Board will
nominate the Employee to the Board, and, if elected, the Employee shall serve
in such capacity without additional consideration.

         2.      TERM OF EMPLOYMENT.  This Agreement shall become effective
upon the Effective Date.  The Employee's employment with the Company shall
continue until terminated by either party at any time, with or without notice,
and for any or no reason.  The parties agree and acknowledge that this
Agreement is an "at will" agreement and that no implied covenant or standard of
practice will cause this Agreement to have any minimum period of employment.

         3.      TERM OF AGREEMENT.  The terms of this Agreement shall
terminate upon the earlier of (i) the date that all obligations of the parties
hereunder have been satisfied, or (ii) the fifth anniversary of the Effective
Date.  Notwithstanding the foregoing, this Agreement may be extended for an
additional period or periods by mutual written agreement of the Company and the
Employee.  A termination of the  terms of this Agreement pursuant to this
Section 3 shall be effective for all purposes, except that such termination
shall not affect any ongoing obligations of the parties hereunder.

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         4.      COMPENSATION.

                 (a)      BASE SALARY.  For all services to be rendered by the
Employee to the Company while this Agreement is in effect, the Employee shall
receive a minimum annual base salary equal to $425,000 (the "Base Salary"),
payable in accordance with the Company's normal payroll practices.  The Base
Salary shall be reevaluated yearly and may be increased by the Board, in light
of the Employee's performance of his duties, provided that in any event, the
Base Salary shall at least be increased each January 1, starting January 1,
2000, by a percentage equal to the percentage increase in the Consumer Price
Index - All Urban Consumers for the New York - Northern New Jersey - Long
Island, NY-NJ-CT-PA area (or any successor Consumer Price Index) for the
preceding year, based on the most recent data published by the Bureau of Labor
Statistics Data of the United States Department of Labor.

                 (b)      JOINING BONUS.  Within fifteen (15) calendar days
after the Effective Date, the Company shall pay the Employee a lump sum cash
bonus equal to $1,000,000.

                 (c)      PERFORMANCE BONUS.  Beginning with the Company's 1999
fiscal year, the Employee shall be entitled to a one-time bonus (the
"Performance Bonus") of $1,000,000 in the event the Company achieves pre-tax
net income in a fiscal year of at least $10,000,000, provided the Employee is
employed with the Company on the last day of such fiscal year.  For this
purpose only, the Company's pre-tax net income shall be determined before
giving effect to any accounting expense attributable to (i) the Employee's
purchase of shares of Company stock pursuant to Section 5(b) below and (ii) the
payment to Employee of any bonus, including any Performance Bonus or Retention
Bonus.  In the event the Employee becomes entitled to the Performance Bonus
hereunder, it shall be paid to the Employee within 90 days after the end of the
applicable fiscal year.  Notwithstanding the foregoing, in the event that on or
before the end of the fiscal year in which such Performance Bonus is earned (i)
the Company terminates the Employee's employment other than for "Cause" or the
Employee terminates his employment for "Good Reason" (as those terms are
defined in Section 10 below), or (ii) the Employee's employment terminates by
reason of the Employee's death or "Disability" (as defined in Section 10), the
Company shall become obligated to pay a prorated Performance Bonus equal to
$1,000,000 multiplied by a fraction, the numerator of which is the actual
pre-tax net income achieved in such fiscal year prior to such termination
(calculated through the end of the calendar month in which such termination
occurs in accordance with the second sentence of this Section 4(c)) and the
denominator of which is $10,000,000, provided that such fraction shall not
exceed one, within fifteen (15) days of such termination.  Thereafter, the
Employee shall become eligible to participate in the Company's executive bonus
plan as then in effect.

                 (d)      RETENTION BONUS.  Provided the Employee remains an
employee of the Company through the first anniversary of the Effective Date,
the Company shall pay to the Executive a bonus (the "Retention  Bonus") of
$1,000,000 within fifteen (15) days of such anniversary.  Notwithstanding the
foregoing, in the event that on or before such first anniversary (i) the
Company terminates





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the Employee's employment other than for "Cause" or the Employee terminates his
employment for "Good Reason" (as those terms are defined in Section 10 below),
or (ii) the Employee's employment terminates by reason of Employee's death or
"Disability" (as defined in Section 10), the Company shall become obligated to
pay the Retention Bonus within fifteen (15) days of such termination.

         5.      OPTIONS; STOCK PURCHASES.

                 (a)      OPTIONS.  As of the Effective Date, the Company shall
grant two (2) options to the Employee covering a total of one million, two
hundred thousand (1,200,000) shares of the Company's Common Stock (the
"Options") pursuant to the Company's Incentive Stock Option Plan, as amended
and restated as of September 21, 1998 and standard form of stock option
agreement as modified to reflect the terms of this Agreement (the "Plan"). The
exercise price of the Options shall be $10.00 per share, i.e., the current fair
market value of a share. Except as otherwise provided herein, the other terms
and conditions of the Options shall be as provided under the Plan.  The First
Option (the "First Option") shall cover 1,000,000 shares and the Second Option
(the "Second Option") shall cover 200,000 shares.  Subject to the Employee's
continued employment with the Company, twenty percent (20%) of the First Option
shall vest and become exercisable on the first anniversary of the Effective
Date, and an additional twenty percent (20%) of the First Option shall vest and
become exercisable at the end of each subsequent annual anniversary of the
Effective Date.  The Second Option shall be fully vested and exercisable as of
the Effective Date.  Notwithstanding the foregoing, in certain circumstances
following a "Change of Control" of the Company (as defined in Section 10 below)
in the event (i) the Company terminates the Employee's employment with the
Company other than for "Cause" or (ii) the Employee terminates for "Good
Reason" (as those terms are defined in Section 10 below), all or a portion of
the then unvested portion of the First Option shall become vested and
exercisable as  provided in Sections 8 or 9 below.

                 (b)      RESTRICTED STOCK.  For a period of thirty (30) days
after the Effective Date, the Employee may purchase from the Company up to
100,000 shares of the Company's Common Stock at a price of $10.00 per share
(the "Restricted Stock").  The Employee may purchase the Restricted Stock with
a full recourse promissory note (the "Note").  The Note shall accrue interest
semiannually at the "applicable federal rate" (within the meeting of Section
1274(d) of the Internal Revenue Code of 1986, as amended (the "Code")), and
shall be subject to repayment in accordance with Section 5(e) below.  Subject
to the Employee's continued employment with the Company, the Restricted Stock
shall vest on the first anniversary of the Effective Date; provided, however,
the Restricted Stock shall vest in full prior to such date in the event (i) the
Company terminates the Employee's employment with the Company for any reason
other than "Cause" or the Employee terminates his employment for "Good Reason"
(as those terms are defined in Section 10 below), or (ii) the Employee's
employment terminates by reason of his death or "Disability" (as defined in
Section 10 below).

                 (c)      STOCK PURCHASE.  Within sixty (60) days of the
Effective Date, the Employee may purchase from the Company up to 250,000 shares
of the Company's Common Stock at a purchase price of $10.00 per share.

                 (d)      STOCK OWNERSHIP RIGHTS AND RESTRICTIONS.  With
respect to shares of the Company's Common Stock that the Employee acquires or
may acquire pursuant to Sections 5(a), (b) and





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(c) above, the Employee shall be made a party to the Amended and Restated
Stockholders Agreement dated April 23, 1998, as amended, among the Company and
the signatories to such Agreement (the "Stockholders Agreement") and will be
deemed a Stockholder, Major Stockholder and Rightholder thereunder, provided
that the Employee agrees to be bound by the terms and conditions of such
Stockholders Agreement.

                 (e)      REPAYMENT OF NOTE.  The Employee's Note (as described
in Section 5(b)) shall be due and payable in full, together with any accrued
but unpaid interest, on the earlier of (i) the first anniversary of the
Effective Date, or (ii) fifteen (15) days after termination of the Employee's
employment with the Company for any reason.

         6.      OTHER BENEFITS.  The Employee shall be entitled to participate
in the employee benefit plans and programs that the Company makes available to
its senior executives, subject to the rules and regulations applicable thereto.
The Company reserves the right to cancel or change the benefit plans and
programs it offers to its senior executive employees at any time.  The Employee
will be eligible for vacation and sick leave in accordance with the policies in
effect for senior executives during the term of this Agreement and will receive
such other benefits and perquisites as the Company generally provides to its
senior executives.

         7.      EXPENSES.  The Company shall pay the Employee a corporate
allowance of $35,000 per fiscal year to be paid to the Employee in a lump sum
at the beginning of such fiscal year (beginning with the 1999 fiscal year) and
used at the Employee's reasonable discretion to cover his Company-related
business expenses.  In addition, the Company shall reimburse the Employee for
reasonable travel, entertainment or other expenses incurred by the Employee in
the furtherance of or in connection with the performance of the Employee's
duties hereunder, in accordance with the Company's expense reimbursement policy
as in effect from time to time.

         8.      TERMINATION.

                 (a)      TERMINATION WITHOUT CAUSE OR FOR GOOD REASON.  If the
Company terminates the Employee's employment other than for "Cause" or if
Employee terminates his employment for  "Good Reason" (as those terms are
defined in Section 10 below), then, subject to the Employee's obligations
pursuant to Section 11 below and in addition to any other amounts to which the
Employee is entitled hereunder:  (i) the Company shall continue to pay the
Employee his Base Salary in effect on the date of such termination for two (2)
years after termination, (ii) the Company shall pay the Employee the "Bonus
Amount" (as defined herein) in a lump sum within fifteen (15) days after
termination, (iii) the Company shall continue to provide the Employee with the
same medical, life and disability benefits as provided to the Employee
immediately prior to such termination or the after-tax cash equivalent,
provided that such amount is sufficient for the Employee to purchase his own
policy, for so long as the Employee is entitled to continuation of Base Salary
as provided herein, provided that such coverage shall become secondary if the
Employee receives coverage from a subsequent employer; and (iv) 60% of the
First Option shall vest upon termination prior to the third anniversary of the
Effective Date, 80% shall vest upon termination on or after the third but prior
to the fourth anniversary of the Effective Date, and





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100% shall vest upon termination on or after the fourth but prior to the fifth
anniversary of the Effective Date.  For purposes of the preceding (iv), the
applicable vesting percentage shall include any portion of the First Option
vested prior to such termination.  In addition, if such termination occurs on
or after the first day of the tenth month of the Company's fiscal year, the
Employee shall be entitled to a lump sum payment within fifteen (15) days of
termination in an amount equal to a prorata portion of the Employee's target
bonus for such fiscal year, based on the number of days in such fiscal year up
to and including the termination date divided by 365, and excluding for this
purpose the Performance Bonus and the Retention Bonus.  For purposes of the
foregoing, the "Bonus Amount" shall mean an amount equal to the greater of (i)
the bonus paid or payable to the Employee with respect to the Company's fiscal
year immediately preceding the fiscal year in which such termination occurs, or
(ii) a prorata portion of the Employee's target bonus for the fiscal year in
which such termination occurs, based on the number of calendar days in such
fiscal year up to and including the termination date divided by 365, and
excluding for this purpose the Performance Bonus and the Retention Bonus.

                 (b)      DEATH OR DISABILITY.  In the event of Employee's
death during the term of this Agreement, the Company shall pay to the
Employee's estate all salary, bonuses and unpaid vacation accrued as of the
date of Employee's death and any other benefits payable under the Company's
then existing benefit plans and policies in accordance with such plans and
policies in effect on the date of death and in accordance with applicable law.
In the event that, during the term of this Agreement, Employee is unable to
perform his job due to Disability (as defined in Section 10 below), the Company
may, at its option, terminate Employee's employment with the Company and such
termination shall entitle the Employee to all salary, bonuses and unpaid
vacation accrued as of the date of such termination and any other benefits
payable under the Company's then existing benefit plans and policies in
accordance with such plans and policies in effect on the date of such
termination and in accordance with applicable law.

                 (c)      VOLUNTARY TERMINATION; TERMINATION FOR CAUSE.  In the
event the Employee's employment with the Company terminates either (i)
voluntarily by the Employee without "Good Reason" (as defined in Section 10
below), or (ii) involuntarily by the Company for "Cause" (as defined in Section
10 below), then the Company shall have no further obligations hereunder except
to pay to the Employee all amounts of unpaid Base Salary and any unpaid bonus
from the prior year, reimburse all reasonable business-related expenses and pay
and provide all other benefits required by law or by the terms of the
applicable plan or benefit program.

         9.      CHANGE OF CONTROL.

                 (a)      OPTION VESTING.  Upon a "Change of Control" (as
defined in Section 10), 100% of the First Option shall vest if such Change of
Control occurs prior to the first anniversary of the Effective Date, 75% shall
vest if such Change of Control occurs on or after the first but prior to the
second anniversary of the Effective Date, 60% shall vest if such Change of
Control occurs on or after the second but prior to the third anniversary of the
Effective Date, 80% shall vest if such Change of Control occurs on or after the
third but prior to the fourth anniversary of the Effective Date, and 100% shall
vest if such Change of Control occurs on or after the fourth anniversary of the
Effective Date.  For





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purposes of the preceding sentence, the applicable vesting percentage shall
include any portion of the First Option that is vested prior to such Change of
Control.  If, during the one-year period following a "Change of Control" of the
Company (as defined in Section 10 below), (i) the Employee terminates his
employment with the Company for "Good Reason" (as defined in Section 10 below),
or (ii) the Company terminates the Employee's employment other than "Cause" (as
defined in Section 10 below), then, subject to the Employee's obligations
pursuant to Section 11 below and in addition to any other amounts to which the
Employee is entitled hereunder, including, but not limited to, payments
provided pursuant to Section 8(a), the First Option shall become 100% vested.

                 (b)      LIMITATION ON PAYMENTS.  In the event that any
payment or benefit received or to be received by the Employee in connection
with a "Change of Control" (as defined in Section 10) or the termination of the
Employee's employment (the "Total Payments") would subject the Employee to the
excise tax imposed under Section 4999 of the Internal Revenue Code of 1986, as
amended (the "Code"), (the "Excise Tax") and the net after-tax amount
receivable by the Employee is less than the net after-tax amount that could
otherwise be payable to the Employee without the imposition of the Excise Tax,
then, subject to Section 9(c) below, to the extent necessary to eliminate the
imposition of the Excise Tax, such Total Payments shall be reduced in the
following order by the least amount which results in the Employee not being
subject to the Excise Tax:  Total Payments payable in cash shall first be
reduced (if necessary, to zero) and Total Payments in connection with stock
options shall next be reduced.  For purposes of this limitation no portion of
the Total Payments shall be taken into account that, in the opinion of tax
counsel selected by the Employee and reasonably acceptable to the Company, does
not constitute a "parachute payment" within the meaning of Section 280G(b)(2)
of the Code, including by reason of Section 280G(b)(4)(A).

                 (c)      CERTAIN BUSINESS COMBINATIONS.  In the event it is
determined by the Board, upon receipt of a written opinion of the Company's
independent public accounts, that the operation of Section 9(b) hereof would
preclude accounting for any proposed business combination of the Company
involving a Change of Control as a pooling of interests, and the Board
otherwise desires to approve such proposed business transaction as a pooling
interests, said Section shall be null and void, but only to the extent
necessary to preserve the pooling treatment.

         10.     DEFINITIONS.    For purposes of this Agreement, the following
terms shall have the following meanings:

                 (a)      CAUSE.  "Cause" shall mean (i) gross negligence or
willful misconduct in the performance of duties to the Company after one
written warning detailing the concerns and offering the Employee opportunities
to cure; (ii) conviction of a felony or a crime involving moral turpitude, in
either event, causing material harm to the standing and reputation of the
Company; or (iii) intentional and improper disclosure of the Company's
confidential or proprietary information which causes material harm to the
Company.

                 (b)      CHANGE OF CONTROL.  A "Change of Control" shall mean
(i) the sale, lease, conveyance or other disposition of all or substantially
all of the Company's assets as an entirety or





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substantially as an entirety to any "person" (as such term is used in Sections
13(d) and 14(d) of Securities Exchange Act of 1934, as amended), entity or
group of persons acting in concert; (ii) any "person"  becoming the "beneficial
owner" (as defined in Rule 13d-3 under said Act), directly or indirectly, of
securities of the Company representing 40% or more of the total voting power
represented by the Company's then outstanding voting securities; (iii) a merger
or consolidation of the Company with any other corporation, other than a merger
or consolidation that would result in the voting securities of the Company
outstanding immediately prior thereto continue to represent (either by
remaining outstanding or by being converted into voting securities of the
surviving entity or its controlling entity) of at least 60% of the total voting
power represented by the voting securities of the Company or such surviving
entity (or its controlling entity) outstanding immediately after such merger or
consolidation; (iv) a change in the composition of the Board of Directors of
the Company occurring within a two (2)-year period, such that a majority of the
then current Board members ceases to be comprised of individuals who either (a)
have been Board members continuously since the beginning of such period, or (b)
have been elected or nominated for election as Board members during such period
by at least a majority of the Board members described in clause (a) who were
still in office at the time such election or nomination was approved by the
Board.

                 (c)      DISABILITY.  A "Disability" shall mean the Employee's
inability to substantially perform his essential job functions as the result of
a physical or mental disability or incapacity for a period of 180 days,
consecutive or otherwise, in any 360-day period.

                 (d)      GOOD REASON.  Resignation for "Good Reason" shall
mean any of the following without the Employee's written consent:  (i) any
material diminution or material adverse change in the Employee's position with
the Company, duties, responsibilities or the positions that report directly to
him, (ii) a reduction by the Company in Employee's Base Salary (in which event
payments provided in Sections 8 and 9 shall be made based upon Employee's Base
Salary in effect prior to any such reduction), (iii) a material reduction in
the aggregate program of employee benefits and perquisites to which Employee is
entitled, (iv) relocation by more than 50 miles from Executive's workplace, (v)
a material decline in Executive's bonus opportunity or (vi) the failure by the
Company to elect, or the removal of, the Employee as a Director, in any event
without Cause.

         11.     NON-COMPETITION AND NON-SOLICITATION.

                 (a)      For a period beginning on the Effective Date  and
ending 18 months after the date on which the Employee ceases to be employed by
the Company for any reason whatsoever, the Employee, directly or indirectly,
whether as owner, sole proprietor, partner, shareholder, director, member,
consultant, agent, founder, co-venturer or otherwise, will:  (i) not engage,
participate or invest in any business activity anywhere in the world which
develops, manufactures or markets products or performs services which are
competitive with the products or services of the Company at the time of the
Employee's termination, or products or services which the Company has under
development or for which are the subject of active planning at the time of the
Employee's termination; provided, however, that the Employee, may own as a
passive investor, publicly-traded securities of any corporation which competes
with the business of the Company so long as such securities do not, in the
aggregate, constitute





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more than 5% of any class of outstanding securities of such corporations; (ii)
refrain from hiring or attempting to employ, recruiting or otherwise
soliciting, inducing or influencing any person to leave employment with the
Company or its resellers or distributors and (iii) refrain from directly or
indirectly soliciting competitive business from any of the Company's customers
and users, resellers or distributors on behalf of any business which competes
the Company.

                 (b)      The Employee understands that the restrictions set
forth in this Section 11 are intended to protect the Company's interest in its
"proprietary information" (as defined in the Confidential Information
Agreement) and establish customer relationships in good will, and agrees that
such restrictions are reasonable and appropriate for this purpose.

                 (c)      The Employee agrees that it would be difficult to
measure any damages caused by  the Company which might result from any breach
by the Employee of the promises set forth in this Section 11, and that in any
event money damages would be an inadequate remedy for any such breach.
Accordingly, the Employee agrees that if the Employee breaches, or proposes to
breach, any portion of  this Section 11, the Company shall be entitled, in
addition all other remedies that it may have, to injunction or other
appropriate equitable relief to restrain any such breach without showing or
proving any actual damage to the Company.



         12.     RIGHT TO ADVICE OF COUNSEL.  The Employee acknowledges that he
has consulted with counsel and is fully aware of his rights and obligations
under this Agreement and of the tax consequences thereof.  The Company shall
pay the legal fees incurred by the Employee in connection with the negotiation
of this Agreement up to $3,000.

         13.     CONFIDENTIAL INFORMATION.  As a condition of Employee's
employment with the Company, the Employee shall execute the Company's standard
form of Confidential Information Agreement.

         14.     SUCCESSORS.

                 (a)      COMPANY'S SUCCESSORS.  Any successor (whether direct
or indirect and whether by purchase, lease, merger, consolidation, liquidation
or otherwise) to all or substantially all of the Company's business and/or
assets shall assume the obligations under this Agreement and agree expressly to
perform the obligations under this Agreement in the same manner and to the same
extent as the Company would be required to perform such obligations in the
absence of a succession.  For all purposes under this Agreement, the term
"Company," shall include any successor to the Company's business and/or assets
which executes and delivers the assumption agreement described in this
subsection (a) or which becomes bound by the terms of this Agreement by
operation of law.

                 (b)      EMPLOYEE'S SUCCESSORS.  Without the written consent
of the Company, the Employee shall not assign or transfer this Agreement or any
right or obligation under this Agreement to any other person or entity.
Notwithstanding the foregoing, the terms of this Agreement and all rights





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of the Employee hereunder shall inure to the benefit of, and be enforceable by,
the Employee's personal or legal representatives, executors, administrators,
successors, heirs, distributees, devisees and legatees.

         15.     NOTICE CLAUSE.

                 (a)      MANNER.  Any notice hereby required or permitted to
be given shall be sufficiently given if in writing and upon mailing by
registered or certified mail, postage prepaid, to either party at the address
of such party or such other address as shall have been designated by written
notice by such party to the other party.

                 (b)      EFFECTIVENESS.  Any notice or other communication
required or permitted to be given under this Agreement will be deemed given on
the day when delivered in person, or the third business day after the day on
which such notice was mailed in accordance with Section 15(a).

         16.     GOVERNING LAW.  This Agreement shall be governed by and
construed in accordance with the internal substantive laws, but not the choice
of law rules, of the state of New York.

         17.     SEVERABILITY.  The invalidity or unenforceability of any
provision of this Agreement, or any terms hereof, shall not affect the validity
or enforceability of any other provision or term of this Agreement.

         18.     INTEGRATION.  Except as otherwise expressly provided otherwise
herein, this Agreement represents the entire agreement and understanding
between the parties as to the subject matter herein and supersedes all prior or
contemporaneous agreements, whether written or oral.  No waiver, alteration, or
modification of any of the provisions of this Agreement shall be binding unless
in writing and signed by duly authorized representatives of the parties hereto.

         19.     TAXES.  All payments made pursuant to this Agreement shall be
subject to withholding of applicable income and employment taxes.

         20.     ARBITRATION.  Except for proceedings seeking injunctive
relief, including, without limitation, allegations of misappropriation of trade
secrets, copyright or patent infringements, or breach of any anti-competition
provisions of this Agreement, any controversy or claim arising out of or in
relation to this Agreement, or the breach thereof, shall be settled by
arbitration in accordance with the commercial arbitration rules of the American
Arbitration Association ("AAA"), and judgment upon the award rendered by the
arbitrator may be entered in any court having jurisdiction thereof.
Arbitration of this Agreement shall include all claims, regardless of whether
the dispute arises during the term of the Agreement, at the time of termination
or thereafter.  Either party may initiate the arbitration proceedings, for
which the provision is herein made, by notifying the opposing party, in
writing, of its demand to arbitrate.  In any such arbitration there shall be
appointed one arbitrator who shall be selected in accordance with the AAA
Commercial Arbitration Rules.  The place of arbitration shall be New York, New
York.  The parties agree that the award of the arbitrator shall be the sole and
exclusive remedy between them regarding any claims, counterclaims, issues or
accounting presented or plead to the





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arbitrator; that the arbitrator shall be the final judge of both law and fact
in arbitration of disputes arising out of or relating to this Agreement,
including the interpretation of the terms of this Agreement.  The parties
further agree it shall be the sole and exclusive duty of the arbitrator to
determine the arbitrability of issues in dispute and that neither party shall
have recourse to the court of such a determination.

         21.     COUNTERPARTS.  This Agreement may be executed by either of the
parties hereto in one or more counterparts, none of which need contain the
signature of more than one party hereto, and each of which shall be deemed to
be an original, and all of which together shall constitute a single agreement.

         IN WITNESS WHEREOF, each of the parties has executed this Agreement,
in the case of the Company by a duly authorized officer, as of the day and year
first above written.


                              OPTIMARK TECHNOLOGIES, INC.

                              By:  /s/  William A. Lupien
                              Chairman


                              PHILLIP J. RIESE

                              By:  /s/  Phillip J. Riese





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