Document:

EXHIBIT 10.17

                               SUBLEASE AGREEMENT

                           1114 Avenue of the Americas

                               New York, New York

         THIS SUBLEASE AGREEMENT, (the "Sublease") is entered into as of the
15th day of June, 2002, by and between THE NORTHWESTERN MUTUAL LIFE INSURANCE
COMPANY, a Wisconsin corporation, ("Sublandlord") and The Ashton Technology
Group, Inc., a Delaware corporation ("Subtenant").

                               W I T N E S S E T H

         WHEREAS, Sublandlord, as tenant, entered into that certain Office Lease
Agreement between 1114 Trizechahn-Swig, L.L.C. (the "Prime Landlord") and
Sublandlord dated December 22,1997, as amended, (the "Prime Lease") for certain
space (the "Premises") consisting of a total of approximately 54,842 rentable
square feet on the twenty-second (22nd) and twenty-third (23rd) floors of the
building located at 1114 Avenue of the Americas, New York, New York (the
"Building"), and

         WHEREAS, Subtenant desires to sublease a portion of the Premises from
Sublandlord.

         NOW, THEREFORE, for Ten ($10) Dollars and in consideration of the
foregoing and for other good and valuable consideration and of the mutual
agreements hereinafter set forth, Sublandlord and Subtenant stipulate, covenant
and agree as follows:

         1.    SUBLEASE PREMISES. Sublandlord does hereby sublease to Subtenant
               a portion of the Premises consisting of approximately 6,000
               square feet of rentable area on the 22nd floor (the "Sublease
               Premises") as outlined with diagonal lines on the floor plan,
               attached hereto and incorporated herein by reference as Exhibit
               B.

         2.    TERM. The term of this Sublease (the "Term") shall be for a
               period of three years commencing on or about June 15, 2002 or the
               date that Prime Landlord provides written approval of this
               Sublease, whichever occurs later, ("Commencement Date") and
               expiring on approximately June 30, 2005, the third anniversary of
               this date (the "Expiration") unless renewed, terminated or
               cancelled earlier as permitted to this Sublease, the Prime lease
               or by operation of law.

         3.    CANCELLATION RIGHT: Both parties have the right to cancel this
               Sublease as of the second (2nd) year anniversary from the
               Commencement Date and at anytime thereafter with 6 months prior
               written notice to the other party. In the event Subtenant
               exercises their option to cancel this Sublease, they shall pay
               Sublandlord a penalty equal to the unamortized portion of the
               brokerage commissions.

<PAGE>

         4.    USE. The Sublease Premises shall be used for general office use
               and no other use. Under no circumstances shall the Sublease
               Premises be used for the sale of life, disability or long term
               care insurance, annuities, and/or other products provided by The
               Northwestern Mutual Life Insurance Company.

         5.    BASE RENT AND ADDITIONAL RENT.

               (a)  Subtenant shall pay Sublandlord rent based on the following
                    schedule (the "Base Rent"): Year one base rent will commence
                    two (2) months (Free Rent) following the Commencement Date.

         Year 1 - $33.00 per Rentable Square Foot or $165,000* per year;
         $16,500.00 monthly Year 2 - $34.00 per Rentable Square Foot or $204,000
         per year; $17,000.00 monthly Year 3 - $37.00 per Rentable Square Foot
         or $222,000 per year; $18,500.00 monthly * as a result of free rent

               (b)  Subtenant shall pay as additional rent (the "Additional
                    Rent") beginning on the one year anniversary of the
                    Commencement Date any Additional Expenses (as such term is
                    defined in Section 4.4.2 of the Prime Lease) in excess of
                    such items paid by Sublandlord to the Prime Landlord for
                    2001 which are due under Articles 4.2 and 4.4, respectively,
                    of the Prime Lease. ("Base Year").

                    Subtenant's prorata share is 10.9% which is the ratio that
                    6,000 square feet of rentable area of the Sublease Premises
                    bears to 54,842 rentable square feet in the Premises.

               (c)  During the Term, Subtenant shall pay a charge for
                    electricity furnished to the Sublease Premises in an amount
                    of Three dollars ($3.00) per rentable square foot annually.

               (d)  If the Commencement Date is not on the first (1st) day of a
                    calendar month or if the expiration is not on the last day
                    of a calendar month, the monthly installment of Base Rent
                    and Additional Rent payable for such month in which such
                    date occurs shall be prorated accordingly.

               (e)  Subtenant will also be responsible for costs for any
                    services requested through the Prime Landlord (the invoicing
                    of these services may flow through the Sublandlord).

                                       2
<PAGE>

         6.    SECURITY DEPOSIT.

               (a)  Subtenant will deliver to Sublandlord $40,000 on the full
                    execution and delivery of this Sublease as security for the
                    full and faithful performance of the terms, covenants, and
                    conditions of this Sublease to be performed or observed by
                    Subtenant, including, but not limited, to payment of Base
                    Rent and Additional Rent or for any other reasonable sum
                    that Sublandlord may expend by reason of Subtenant's
                    default, including any damages or deficiency in reletting
                    the Sublease Premises, in whole or in part, whether such
                    damages accrue before or after summary proceedings or other
                    reentry by Sublandlord. If Subtenant fully and faithfully
                    complies with all the terms, covenants, and conditions of
                    this Sublease to be performed or observed by Subtenant
                    during the Term, cash deposit or any unapplied balance of it
                    will be released to Subtenant upon surrender of possession
                    of the Sublease Premises to Sublandlord. An interest rate of
                    (two) percent (2 %) per annum will be paid on the Security
                    Deposit that will be held by Sublandlord. Should a portion
                    of the Security Deposit be required to cure any default as
                    described above, then the interest will be calculated on the
                    lowest balance.

         7.    INCORPORATION OF PRIME LEASE.

               (a)  This Sublease is subject and subordinate to all of the terms
                    of the Prime Lease, and to all matters to which the Prime
                    Lease is or shall be subordinate, with the same force and
                    effect as if fully set forth herein at length, excepting
                    only as otherwise specifically provided herein. Except for
                    the obligation to pay Base Rent and Additional Rent all of
                    the terms with which Sublandlord is bound to comply under
                    the Prime Lease shall, to the extent only that they apply to
                    the Sublease Premises and except to the extent they are
                    inapplicable or inconsistent with the same or as otherwise
                    provided herein, be binding upon Subtenant, and all of the
                    obligations of Prime Landlord set forth in the Prime Lease
                    shall, to the extent that they apply to the Sublease
                    Premises, inure to Subtenant's benefit. It is the intention
                    of the parties that, except as otherwise provided in this
                    Sublease, the relationship between Sublandlord and Subtenant
                    shall be governed by the language of the various articles of
                    the Prime Lease as if they were typed out in this Sublease
                    in full, and the words "Landlord", "Tenant", "Premises" and
                    "Lease" as used in the Prime Lease, shall read,
                    respectively, "Sublandlord", "Subtenant", "Sublease
                    Premises" and "Sublease".

               (b)  For the purposes of this Sublease, only the following
                    provisions of the Prime Lease do not apply:(i) Delete in
                    their entirety items (d), (e), (g), (h), (i), (j), (k), (l),
                    (m), (n) and (s) of Section 1.1, titled "Basic Lease
                    Definitions"; items (a), (m) and (o) of Section 1.3, titled
                    "Additional Definitions"; Sections 3.1, 3.2 and 3.3 of
                    Article 3, titled "Term"; Sections 4.1, 4.4, and 4.5 of
                    Article 4, titled "Rent"; Section 16.10, titled" "Initial

                                       3
<PAGE>

                    Subleasing"; and Article 28, titled "Renewal Option". With
                    respect to the Sublease Premises, Subtenant shall be
                    entitled to the same rights from the Prime Landlord as the
                    Sublandlord is entitled as the tenant under the Prime Lease.

               (c)  Subtenant is not and will not be entitled toward any Rent
                    Abatement or Tenant Improvement Allowance outlined in the
                    Prime Lease or anywhere else, except as otherwise provided
                    herein.

         8.    QUIET ENJOYMENT.

               (a)  Sublandlord covenants and agrees with Subtenant that upon
                    Subtenant paying Base Rent and Additional Rent reserved in
                    this Sublease and observing and performing all of the other
                    obligations, terms, covenants and conditions of this
                    Sublease on Subtenant's part to be observed and performed,
                    Sublandlord shall not disturb or terminate Subtenant's
                    leasehold estate hereunder and Subtenant may peaceably and
                    quietly enjoy the Sublease Premises during the Term;
                    provided, however, that this Sublease shall automatically
                    terminate upon termination of the Prime Lease and Subtenant
                    shall have no claim against Sublandlord unless such
                    termination was caused by the default of Sublandlord in the
                    performance of its obligations under the Prime Lease.

               (b)  Subtenant covenants and agrees that Subtenant shall not do
                    or suffer or permit anything to be done which would
                    constitute a default, beyond any applicable cure or notice
                    period, under the Prime Lease or would cause the Prime Lease
                    to be canceled, terminated or forfeited by virtue of any
                    rights of cancellation, termination, or forfeiture reserved
                    or vested in Prime Landlord under the Prime Lease, and that
                    Subtenant will indemnify and hold harmless Sublandlord from
                    and defend Sublandlord against all claims, liabilities,
                    losses and damages of any kind whatsoever (excepting special
                    and consequential damages) that Sublandlord may incur by
                    reason of, resulting from or arising out of any such
                    cancellation, termination or forfeiture.

               (c)  Sublandlord covenants that it shall not voluntarily
                    surrender or terminate the Prime Lease except as set forth
                    in Paragraph 3, hereof. The foregoing is not intended to
                    limit Sublandlord's ability to terminate the Prime Lease in
                    the event of a casualty or condemnation, Premises other than
                    the Sublease Premises, or Sublandlord's election not to
                    exercise its option to renew the Prime Lease as provided
                    therein.

               (d)  Sublandlord shall duly pay each installment of the Rent and
                    Additional Rent under the terms of the Prime Lease and will
                    duly observe and perform every term and condition of the
                    Prime Lease to the extent that such term

                                       4
<PAGE>

                    and conditions not provided in this Sublease to be observed
                    or performed by Subtenant.

         9.    NOTICES.

               (a)  Any notice, demand or request under this Sublease shall be
                    in writing and shall be considered properly delivered when
                    addressed as hereinafter provided and delivered by overnight
                    courier (signature of receipt required), certified mail
                    (return receipt requested) which is deposited in the United
                    States general or branch post office, or delivered by
                    private express mail service (signature of receipt
                    required); or via facsimile. Any notice, demand or request
                    by Sublandlord to Subtenant shall be addressed to Subtenant
                    at:

                    The Ashton Technology Group Inc.
                    The Grace Building
                    1114 Avenue of the Americas 22nd Floor
                    New York, New York 10036
                    Attention: Mr. James Pak, Chief Financial Officer

                    With Copy to:

                    Cole, Schotz, Meisel, Foreman and Leonaerd, P.A.
                    25 Main Street
                    Hackensack, NJ  07601
                    Attn: Stanley Stern, Esq.

                    TrizecHahn Office Properties
                    1114 Avenue of the Americas, 31st Floor
                    New York, NY 10036

                    Until otherwise directed in writing by Subtenant. Any
                    notice, demand or request by Subtenant to Sublandlord
                    shall be addressed to Sublandlord at:

                    The Northwestern Mutual Life Insurance Company
                    720 East Wisconsin Avenue

                    Milwaukee, WI  53202
                    Attn: Field Financial Services Department - Gabriel

                    Rejection or other refusal to accept or the inability to
                    deliver because of a changed address of which no notice was
                    given shall be deemed to be receipt of the notice, demand or
                    request sent.

               (b)  Sublandlord shall promptly notify the Prime Landlord to add
                    Subtenant and its attorney (as set forth herein) as
                    additional parties who are entitled

                                       5
<PAGE>

                    to receive copies of all notices under the Prime Lease.
                    Sublandlord shall cooperate with Subtenant in all respects
                    in connection with Subtenant's exercise of its rights
                    hereunder including, without limitation, using reasonable
                    efforts to obtain all necessary consents required of the
                    Prime Landlord pursuant to the Prime Lease.

         10.   ASSIGNMENT OR SUBLEASE BY SUBTENANT. Subject to the Prime
               Landlord's approval, Subtenant acknowledges and agrees that
               Subtenant may not assign or sublet the Sublease Premises without
               Sublandlord's consent.

         11.   ASSIGNMENT BY SUBLANDLORD. Subtenant acknowledges and agrees that
               Sublandlord may assign all of Sublandlord's rights, title and
               interest in and to the Prime Lease and this Sublease to any
               person or entity permitted pursuant to the Prime Lease provided
               such assignee shall assume the rights and liabilities of
               Sublandlord and perform all its obligations under the Prime Lease
               and this Sublease. Upon such assignment, Subtenant agrees to
               attorn to the such assignee as its Sublandlord and Subtenant
               shall continue to be bound under all of the terms, covenants and
               conditions of this Sublease for the balance of the Term hereof.

         12.   PRIME LANDLORD'S RESPONSIBILITIES. Subtenant recognizes that
               Sublandlord is not in a position to furnish the services set
               forth in the Prime Lease, obtain an agreement of non-disturbance,
               or to perform certain other obligations which are not within the
               control of Sublandlord, such as, without limitation, maintenance,
               repairs and replacements to the Premises and Sublease Premises,
               compliance with laws, and restoration of the Sublease Premises
               and building after casualty or condemnation. Notwithstanding
               anything to the contrary contained in this Sublease, Sublandlord
               and Subtenant agree that Subtenant shall look solely to Prime
               Landlord to furnish all such services and to perform all such
               obligations which by Prime Landlord is obligated under the Prime
               Lease to furnish and perform. Sublandlord shall not be liable to
               Subtenant or be deemed in default hereunder for failure of Prime
               Landlord to furnish or perform the same

         13.   CASUALTY AND CONDEMNATION. Subtenant's rights and obligations
               under Article 13, titled "Damage or Destruction" and Article 15,
               titled "Condemnation", of the Prime Lease shall be that if by
               operation of either of these two Articles the Prime Lease is not
               terminated and continues in full force and effect, this Sublease
               shall not be terminated but shall also continue in full force and
               effect, except that until the Sublease Premises are restored in
               accordance with these two Articles as the case may be there shall
               be a proportionate abatement of Base Rent and Additional Rent
               payable hereunder either to the extent of damage to the Sublease
               Premises as determined by Prime Landlord, Sublandlord and
               Subtenant; provided, however, that such abatement shall in no
               event exceed the abatement granted to Sublandlord under the Prime
               Lease for the Sublease Premises and, provided further, that no

                                       6
<PAGE>

               compensation or claim or reduction will be allowed or paid by
               Sublandlord by reason of inconvenience, annoyance or injury to
               Subtenant's business arising from the necessity of effecting
               repairs to the Sublease Premises or any portion of the Premises,
               whether such repairs are required by operation of these two
               Articles or any other provision of the Prime Lease, except to the
               extent that Sublandlord receives compensation or claim from the
               Prime Landlord, in which event Subtenant shall be entitled to a
               pro-rata share of such compensation, claim and/or reduction to
               the extent that the Sublease Premises are affected by any
               casualty or condemnation. .

         14.   BINDING AND ENTIRE AGREEMENT. This Sublease shall be binding on
               Subtenant and Sublandlord and their respective heirs and
               executors, and on the respective legal representatives,
               successors and permitted assigns of the parties. This Sublease
               contains the entire agreement of the parties with respect to the
               subject matter herein and may not be modified except by
               instrument in writing which is signed by both parties.

         15.   CONSENT OF PRIME LANDLORD. Anything hereinabove to the contrary
               notwithstanding, it is understood and agreed that this Sublease
               shall not become effective unless and until Sublandlord has
               obtained and delivered to Subtenant the written consent of Prime
               Landlord to the subletting herein on or before June 15, 2002,
               failing which either party may at its option, by giving the other
               notice on or before June 30, 2002, elect to terminate this
               Sublease. If this Sublease is terminated as aforesaid, neither
               party hereto shall have any further claim against the other
               hereunder and all monies paid by Subtenant to Sublandlord shall
               be promptly returned.

         16.   SUBLANDLORD WORK CONTRIBUTION. It is understood that the
               Subtenant accepts the Premises in an "as is" condition.
               Sublandlord will paint the space where necessary. It is further
               understood any and all other costs associated with occupying the
               Sublease Premises will be the Subtenant's responsibility. Any
               work must be completed according to the terms of the Prime Lease.

         17.   FURNITURE. For the Term , providing Subtenant is not in default,
               after notice and the expiration of any applicable cure period,
               Subtenant will have use of the workstations contained in the
               Subleased Premises ("Furniture") at no charge. The title of the
               Furniture shall remain with the Sublandlord or an affiliate
               general agent. Subtenant will be responsible for all and any
               repairs or maintenance of the Furniture and shall return the
               Furniture in working order, normal wear and tear excepted, at the
               end of the Term. In the event that any local property taxes are
               assessed on the Furniture during the Term, Subtenant shall be
               solely responsible for the payment of any such taxes assessed on
               the Furniture.

         17.   HOLDING OVER. Subtenant shall have no right to remain in
               possession of all or any part of the Sublease Premises after the
               expiration of the Term. If Subtenant

                                       7
<PAGE>

               remains in possession of all or any part of the Sublease Premises
               after the expiration of the Term, : (a) such tenancy shall be
               deemed to be a periodic tenancy from month-to-month only; (b)
               such tenancy shall not constitute a renewal or extension of this
               Sublease for any further term; and (c) such tenancy may be
               terminated by Sublandlord upon the earlier of 30 days' prior
               written notice or the earliest date permitted by law. In the
               event Subtenant remains in possession after the expiration of the
               Term, monthly installments of Base Rent shall be increased to an
               amount equal to two hundred percent (200%) of the monthly
               installments of Base Rent as charged at that given time by the
               Prime Landlord for the occupied space defined in the Prime Lease
               or any amendments, and any other sums and Additional Rent due
               under this Sublease shall be payable in the amount and at the
               times specified in this Sublease. Such month-to-month tenancy
               shall be subject to every other term, condition, and covenant
               contained in this Sublease.

         18.   INSURANCE. During the Term, Subtenant shall provide Sublandlord
               with satisfactory evidence of insurance for the Subleased
               Premises in accordance with the terms of Section 12 of the Prime
               Lease.

         19.   REPRESENTATIONS AND WARRANTIES. Sublandlord warrants and
               represents the following subparagraphs

               (a)  it is holder of the entire interest of the tenant under the
                    Prime Lease

               (b)  the Prime Lease and any and all amendments and modifications
                    thereto have been delivered to Subtenant and the same have
                    not been further modified or amended;

               (c)  the Prime Lease is in full force and effect and there are no
                    defaults or events with the giving of notice or the passage
                    of time which would constitute defaults by the Prime
                    Landlord or Sublandlord under the Prime Lease;

               (d)  Sublandlord has not received notice from any governmental
                    authority regarding non-compliance with applicable laws
                    relating to the Sublease Premises;

               (e)  Sublandlord has received no notice of any violation, action,
                    suit, claim or proceeding threatened against or affecting
                    the Sublease Premises

               (f)  Sublandlord has not sold, assigned, transferred, mortgaged
                    or pledged its interest as tenant under the Prime Lease; and

                                       8
<PAGE>

               (g)  The execution and delivery of this Sublease has been duly
                    authorized by Sublandlord and the persons(s) execution this
                    Sublease on behalf of the Sublandlord have been duly
                    authorized to do so.

         20.   BROKER. Sublandlord and Subtenant warrant and represent that
               neither has had any dealings or communications with any broker or
               agent in connection with the consummation of this Sublease other
               than CB Richard Ellis, Inc. ("Brokers"). Sublandlord and
               Subtenant agree to defend, hold harmless and indemnify each other
               from and against any and all cost, expenses (including reasonable
               attorney's fees) or liability for any compensation, commission or
               charge claimed by any other broker or agent other than Brokers
               with respect to this Sublease or the negotiation thereof.
               Sublandlord agrees to pay the Brokers pursuant to a separate
               agreement between Sublandlord and Brokers.

         21.   MODIFICATIONS TO PRIME LEASE. Sublandlord covenants and agrees
               that it will not enter into any amendment, modification or other
               agreement with respect to the Prime Lease which relates to the
               Sublease Premises which would reduce the Subtenant's rights or
               increases Subtenant's obligations under this Sublease.

         22.   SUBLANDLORD'S CERTIFICATE. At any time, and from time to time,
               within ten (10) days after written request from Subtenant,
               Sublandlord shall execute, acknowledge and deliver to Subtenant
               (or to any other party designated by Subtenant) a written
               statement certifying: (a) that this Sublease has not been
               modified and is in full force and effect, as modified, and
               stating such modification(s); (b) the dates to which the rent and
               additional rent and other charges hereunder have been paid; (c)
               whether any default or event with which the giving of notice or
               the passage of time would constitute a default exists under this
               Sublease, and if so, specifying such default; and (d) any other
               reasonable information requested by Subtenant.

         23.   CONSENT. Whenever in this Sublease (or the Prime Lease) Subtenant
               may be required to first obtain the consent or approval of the
               Prime Landlord prior to obtaining Sublandlord's consent or
               approval, Sublandlord agrees that it shall use reasonable efforts
               to assist Subtenant in obtaining the same.

         24.   GOVERNING LAW. The Sublease shall be governed by and construed in
               accordance with the laws of the State of New York.

         25.   SIGNAGE. Sublandlord will provide to Subtenant a pro rata share
               (based upon the square footage) of the directory signage rights
               given to Sublandlord under the Prime Lease. Subtenant will need
               to arrange, at their cost, any building directory services
               directly with Prime Landlord without limiting Sublandlord's
               remaining building directory rights. With Sublandlord and Prime
               Landlord's written approval, Subtenant shall be permitted to
               install signage on approved areas of the

                                        9
<PAGE>

               hallway leading to the Sublease Premises and on entrance doors.
               All signage must adhere to any local building codes.

         26.   COUNTERPARTS. This Sublease may be executed in one or more
               counterparts, each of which shall be deemed as original and all
               of which together shall constitute one and the same instrument.

         IN WITNESS WHEREOF, duly authorized representatives of the parties
hereto have executed this Sublease as of the day and year first above written.

SUBLANDLORD:               THE NORTHWESTERN MUTUAL LIFE
                           INSURANCE COMPANY,
                           a Wisconsin corporation

                           By:/s/Christina H. Fiasca
                              -------------------------------------
                           Name: Christina H. Fiasca
                           Title: Vice President

SUBTENANT:                 The Ashton Technology Group Inc.

                           By:/s/James S. Pak
                              -------------------------------------
                           Name: James S. Pak
                           Title:  Chief Financial Officer

                                       10
<PAGE>

                                 SUBLEASE RIDER

A.   REPRESENTATIONS, WARRANTIES AND COVENANTS OF SUBLANDLORD:
     ---------------------------------------------------------
B.

     Sublandlord represents and warrants to Subtenant, and covenants as follows:

(i) Sublandlord has not given or received any notice of any default under the
Prime Lease, which default remains uncured, and, to the best of its knowledge,
no event has occurred or failed to occur which with the passage of time and/or
the giving of notice would ripen into such a default;

(i) Sublandlord has not received written notice of any violation of any
applicable laws or insurance requirements (including, without limitation,
environmental laws), and, to the best of Sublandlord's actual knowledge, the
Sublease Premises and the Building comply with all such laws and requirements;

(i) Sublandlord shall pay all rent and perform all of the obligations required
to be performed by Sublandlord under the Prime Lease (and not assumed by
Subtenant under this Sublease), and not to do or suffer or permit anything to be
done which would result in a default under, or cause the Prime Lease to be
terminated or forfeited;

(i) Sublandlord shall not, without Subtenant's consent, which consent shall not
be unreasonably withheld or delayed, except as expressly provided hereunder, (1)
cancel, surrender or terminate the Prime Lease, or (2) amend or modify the Prime
Lease, the result of which would materially or adversely affect Subtenant's
rights or obligations hereunder or the Sublease Premises, and any such
cancellation, surrender, termination (except as expressly provided hereunder),
amendment or modification of the Prime Lease made without Subtenant's consent
shall not be binding on Subtenant to the extent the same materially decreases
the rights or materially increases the obligations of Subtenant with respect to
the Sublease Premises or this Sublease;

(i) there is no pending and, to the best of Sublandlord's actual knowledge,
threatened litigation affecting Sublandlord's interest in the Prime Lease or the
Sublease Premises;

(i) there is no litigation pending between Sublandlord and Prime Landlord;

                                       11
<PAGE>

(i) Sublandlord has all of the requisite corporate power and authority to
execute, deliver and perform its obligations under this Sublease and the Prime
Lease, and the person executing and delivering this Sublease on behalf of
Sublandlord has the requisite authority to perform such acts on behalf of
Sublandlord;

(i) Sublandlord shall, promptly following receipt thereof, deliver to Subtenant
a copy of any notice received by it from Prime Landlord which would have any
adverse effect upon the Sublease Premises or this Sublease;

(i) Sublandlord agrees that, with respect to any non-disturbance agreement it
has or may hereafter enter into with respect to the Prime Lease, it will enforce
for the benefit of the Sublease Premises and Subtenant, the terms of any such
non-disturbance agreement that it has the right to enforce;

(i) there are no defaults under the Prime Lease by Prime Landlord of which
Sublandlord has actual notice or knowledge;

(i) except as expressly provided herein, Sublandlord has obtained all necessary
consents and approvals to enter into this Sublease;

(i) Sublandlord has no actual knowledge of any pending or threatened
condemnation against the Building or the Sublease Premises;

(i) in the event Subtenant is obligated (whether pursuant to this Sublease, by
law or otherwise) to pay or reimburse Sublandlord for counsel or attorneys'
fees, costs, disbursements, fees, expenditures, charges or expenses, it shall be
deemed that Subtenant shall only be obligated to pay or reimburse Sublandlord
for Sublandlord's reasonable counsel or attorneys' fees, and reasonable costs,
disbursements, fees, expenditures, charges or expenses;

(i) Sublandlord shall use reasonable efforts to minimize interference with
Subtenant's business in connection with any entry in and to the Sublease
Premises, or in connection with any inspection or showing thereof, by
Sublandlord, pursuant to the terms, covenants, conditions, provisions and
agreements of this Sublease;

(i) to the extent not prohibited in the Prime Lease, Subtenant shall be
permitted to have access to the Sublease Premises on a twenty-four (24) hour,
seven (7) day per week basis; provided, however, that Subtenant shall be solely
responsible for any additional charges associated with any such access to the
Sublease Premises outside of

                                       12
<PAGE>

the Building's standard hours of operation as such hours of operation are set
forth in the Prime Lease;

(i) Sublandlord agrees to use reasonable efforts to re-let the Sublease Premises
and to mitigate its damages in the event of a default by Subtenant hereunder;

(i) in the event Sublandlord does not consent or give its approval, Sublandlord
shall specify the reason(s) therefor to Subtenant in writing;

(i) Subtenant may make cosmetic/decorative changes in and to the Sublease
Premises, without Sublandlord's prior written consent, provided the cost of any
such cosmetic/decorative changes does not exceed $1,000.00 and, with respect to
all other cosmetic/decorative changes, subject to the Prime Lease, Sublandlord
shall not unreasonably withhold, condition or delay its consent;

(i) all demands made by Sublandlord for payment of additional rent by Subtenant
hereunder, shall be accompanied by appropriate supporting documentation
including, but not limited to, invoices and/or other billing statements rendered
by Sublandlord;

(i) the Sublease Premises are free from all occupancies or tenancies whatsoever;

(i) to the best of Sublandlord's actual knowledge, the Sublease Premises and the
Building contain no asbestos, urea formaldehyde, chlorofluorocarbons or other
toxic or hazardous substances or wastes; and

A. ATTORNEYS' FEES:
   ----------------
B.

     If either party institutes any action or proceeding against the other
for the violation of any of the terms, covenants, conditions, provisions or
agreements of this Sublease, and if either party shall be successful in such
action or proceeding, then the unsuccessful party shall be obligated to pay or
reimburse the successful party for reasonable attorneys' fees incurred in
connection with the institution and prosecution of such action or proceeding.

A.   ASSIGNMENT/SUBLETTING:
     ----------------------
B.

     Subject to Prime Landlord's consent, if applicable, and subject to any
actual out-of-pocket reasonable costs that may be incurred by Sublandlord in
connection with same, Subtenant may assign this Sublease or sublet all or any
part of the Sublease Premises, without the prior written consent of Sublandlord,
to:

                                       13
<PAGE>

(i) any parent, subsidiary or affiliate of Subtenant; or
(ii) any entity resulting from a merger or consolidation with Subtenant; or
(iii) any entity succeeding to the business and assets or stock of Subtenant.

B.   DELIVERY OF SUBLEASE PREMISES:
     ------------------------------
C.

     Sublandlord agrees to deliver the Sublease Premises to Subtenant on the
commencement date of this Sublease, in vacant and "broom-clean" condition, free
of all tenancies and occupancies whatsoever. If for any reason Sublandlord is
unable to give Subtenant possession of the Sublease Premises by June 15, 2002,
and in the condition as aforesaid, Subtenant may terminate this Sublease upon
three (3) business days written notice to Sublandlord, and if Subtenant so
elects to terminate this Sublease as aforesaid, all sums paid by Subtenant
hereunder shall be returned to Subtenant forthwith.

A.   ENFORCEMENT OF PRIME LEASE:
     ---------------------------
B.

     If Prime Landlord shall default in any of its obligations to Sublandlord
with respect to the Sublease Premises, Sublandlord shall use its best efforts to
enforce its rights against Prime Landlord, and Subtenant shall be entitled to
participate with Sublandlord in the enforcement of Sublandlord's rights against
Prime Landlord. If, after written requests from Subtenant, Sublandlord shall
fail or refuse within ten (10) days thereafter to take appropriate action for
the enforcement of Sublandlord's rights against Prime Landlord with respect to
the Sublease Premises, Subtenant shall have the right to take such action in its
own name, and for that purpose and only to such extent, all of the rights of
Sublandlord under the Prime Lease with respect to the Sublease Premises are
hereby conferred upon and assigned to Subtenant. Sublandlord agrees to cooperate
with Subtenant in connection with the enforcement by Subtenant of such rights.
In the event that any such action against Prime Landlord can only be taken in
Sublandlord's name by reason of lack of privity, non-assignability or otherwise,
Sublandlord shall permit Subtenant to take such action against Prime Landlord in
Sublandlord's own name, at the sole cost and expense of Subtenant (including all
attorneys' fees and disbursements), and Sublandlord shall execute all documents
reasonably required in connection therewith.

A.   MISCELLANEOUS:
     --------------
B.

(i) Subtenant shall not be deemed to be making any representations and
warranties which were made by Sublandlord as tenant under the Prime Lease.
(ii)
(iii) Subtenant shall be permitted to directly contact Prime Landlord with
respect to the maintenance and repair of the Sublease Premises, and the
providing of services and utilities therein (e.g., "after-hours").

                                       14EXHIBIT 10.23

                        THE ASHTON TECHNOLOGY GROUP, INC.

                                 PROMISSORY NOTE

$300,000                                                          April 30, 2002

          FOR VALUE RECEIVED, the undersigned, THE ASHTON TECHNOLOGY GROUP,
INC., a Delaware corporation (the "Company"), and each of the Subsidiaries
(together with the Company, the "Borrowers" and each, a "Borrower"), jointly and
severally, hereby promises to pay to OPTIMARK INNOVATIONS INC., a Delaware
corporation, or its assigns (the "Payee"), the principal sum of THREE HUNDRED
THOUSAND DOLLARS ($300,000), or such lesser principal amount as shall then equal
the outstanding principal amount thereof, plus interest.

          1. Interest Rate. Interest on the outstanding principal balance of
this Note shall accrue at the rate of ten percent (10%) per annum, computed on
the basis of a 360-day year for the actual number of days elapsed. Interest
shall be compounded every ninety (90) days from the date hereof and shall accrue
from the date hereof until all amounts arising under this Note are paid in full.
Upon the occurrence and during the continuance of an Event of Default (as
defined in Section 10 of this Note), interest on the outstanding principal
balance of this Note shall accrue at the Default Rate (as defined in Section 12
of this Note).

          2. Payment of Principal and Interest. The outstanding principal
balance of this Note, together with all accrued but unpaid interest, shall be
due and payable on the earlier to occur of (i) the date of the closing (the
"Closing") of the transactions contemplated by that certain Securities Purchase
Agreement, dated as of February 4, 2002 (as amended on March 6, 2002, the
"Securities Purchase Agreement") by and between the Company and the Payee, or
(ii) May [10], 2002 (the "Maturity Date"). The principal, interest and other
sums due on this Note shall be reflected by the Payee's records which will be
prima facie evidence of the computation of the amounts owing by the Company to
the Payee, absent manifest error. Payment of both principal and interest on this
Note shall be in such coin or currency of the United States of America as at the
time of payment shall be legal tender for the payment of public and private
debts and shall be payable at the principal office of the Payee or at such other
address designated in writing by the Payee to the Company, as designated agent
of the Borrowers.

          3. Pre-Payment. The Borrowers may prepay, without penalty or premium,
all or any portion of the unpaid principal amount of this Note, together with
accrued interest on the amount prepaid.

          4. Compliance with Laws. It is expressly stipulated and agreed to by
the Borrowers and the Payee at all times that it is their intent to comply with
applicable state law or applicable United States federal law (to the extent it
permits the Payee to contract for, charge, take, reserve or receive a greater
amount of interest than under state law) and that this section shall control
every other covenant and agreement in this Note. If the applicable law (state or
federal) is ever judicially interpreted so as to render usurious any amount
called for under this

<PAGE>
                                                                               2

Note, or contracted for, charged, taken, reserved or received with respect to
the indebtedness evidenced by this Note, then it is each Borrower's and the
Payee's express intent that all excess amounts theretofore collected by the
Payee be credited on the principal balance of this Note (or, if this Note has
been or would thereby be paid in full, refunded to the Company, as agent of the
Borrowers), and the provisions of this Note immediately be deemed reformed and
the amounts thereafter collectible hereunder and thereunder reduced, without the
necessity of the execution of any new document, so as to comply with the
applicable law, but so as to permit the recovery of the fullest amount otherwise
called for hereunder and thereunder.

          5. Waiver of Presentment, etc. Each Borrower and all endorsers of this
Note hereby waive presentment, demand, protest and notice. The Payee shall,
promptly upon full payment by the Borrowers of the principal of and interest on
this Note, together with all costs and expenses, if any, due hereon, surrender
this Note to the Company, as agent for the Borrowers, for retirement and
cancellation; provided, however, that to the extent the Borrowers make a payment
or payments to the Payee, which payment or payments or any part thereof are
subsequently invalidated, declared to be fraudulent or preferential, set aside,
and/or required to be repaid to a trustee, receiver, or any other party under
the United States Bankruptcy Code, as amended, any state or federal law, common
law, or equitable causes (a "Voidable Transfer") and the Payee is required to
repay or restore any such Voidable Transfer or the amount or any portion
thereof, or upon the advice of its counsel is advised to do so, then as to any
such Voidable Transfer or the amount repaid or restored (including all
reasonable costs, expenses and attorneys' fees of the Payee related thereto),
the joint and several liability of the Borrowers shall automatically be revived,
reinstated and restored and shall exist in full force and effect as though such
Voidable Transfer had never been made.

          6. Collection Costs. Should the indebtedness evidenced by this Note or
any part thereof be collected in any proceeding at law, or this Note be placed
in the hands of attorneys for collection after default by the Borrowers, jointly
and severally, in making due and punctual payment of principal at maturity and
interest hereunder, the Borrowers, jointly and severally, agree to pay all costs
of collecting this Note, including reasonable attorneys' fees and expenses and
court costs, if any.

          7. Protective Covenants. For so long as any amounts remain outstanding
under this Note, the prior approval of the Payee shall be required for the
Company to:

               (a) authorize or issue any equity security, other than shares of
Common Stock underlying options granted and outstanding as of the date of this
Note;

               (b) increase the aggregate authorized number of shares of Common
Stock or any other class or series of capital stock of the Company;

               (c) enter into any agreement with any holder of any securities of
the Company or any Subsidiary giving such holder the right to require the
Company or such Subsidiary to initiate any registration of the Company's or such
Subsidiary's securities under the Securities Act of 1933, as amended;

<PAGE>
                                                                               3

               (d) repurchase or redeem any of the Company's or any Subsidiary's
securities;

               (e) (i) merge, combine or consolidate with, or agree to merge,
combine or consolidate with, or purchase, or agree to purchase, all or
substantially all of the securities of, any Person or (ii) purchase, or agree to
purchase, all or substantially all of the assets and properties of, or otherwise
acquire, or agree to acquire, all or any portion of, any Person;

               (f) sell all or substantially all of the Company's or any
Subsidiary's assets;

               (g) alter or change materially or adversely, the rights of the
Common Stock or any other class or series of capital stock of the Company;

               (h) make any capital expenditures in excess of $25,000 in any
fiscal year;

               (i) incur debt or guarantees (other than trade payables incurred
by the Company in the ordinary course of business) in excess of $25,000;

               (j) make any loan or advance, other than travel advances to
employees in the ordinary course of business;

               (k) adopt any employee benefit, bonus or stock plan;

               (l) engage in any transaction with any Affiliate or officer,
director or stockholder (or their relatives), other than in the ordinary course
of business and at arms-length;

               (m) amend or propose to amend the Company's certificate of
incorporation or by-laws;

               (n) liquidate or dissolve, effect any recapitalization or
reorganization, or any stock split, reverse stock split, or, in each case,
obligate the Company or its Subsidiaries to do so;

               (o) declare or pay any dividend or make any other distribution to
its stockholders in respect of any shares of its capital stock; or

               (p) engage in any other business other than that business
currently engaged in by the Company and its Subsidiaries.

          8. Assignment. Neither this Note nor the rights and obligations of any
Borrower may be assigned by such Borrower without the prior written consent of
the Payee and any attempted assignment in contravention of this Note shall be
null and void and of no effect. The Payee may assign its rights or obligations
hereunder to any Affiliate of the Payee; provided that, in the event that any
such assignment is in violation of any federal securities laws or any rules or
regulations of the NASD or would result in the delisting of the Company's
securities

<PAGE>
                                                                               4

from the Nasdaq OTC Bulletin Board, such assignment shall be null and void and
of no force or effect. This Note when surrendered for assignment or transfer by
the Payee shall be accompanied by the Assignment Form attached hereto duly
executed by the Payee. Effective upon any such assignment, the Person to whom
such rights, interests and obligations were assigned shall have and exercise all
of the Payee's rights, interest and obligations hereunder as if such Person were
the original Payee of this Note.

          9. No Rights as Stockholder; Note is Debt. This Note does not entitle
the Payee hereof to any voting rights or other rights as a stockholder of any
Borrower. Each Borrower shall treat, account and report this Note as debt and
not equity for accounting and tax purposes.

          10. Event of Default. In the case of an Event of Default (as defined
below), the principal of and accrued and unpaid interest on the Note shall ipso
facto become and be immediately due and payable without any declaration or other
act on the part of any holder. For purposes hereof, "Event of Default" means the
occurrence of any of the following:

               (a) the entry of a decree or order for relief by a court having
jurisdiction in the premises in respect of any Borrower in an involuntary case
under the federal bankruptcy laws, as now constituted or hereafter amended, or
any other applicable federal or state bankruptcy, insolvency or other similar
laws, or appointing a receiver, liquidator, assignee, custodian, trustee,
sequestrator (or similar official) of any Borrower or for any substantial part
of their property, or ordering the winding-up or liquidation of any of their
affairs and the continuance of any such decree or order unstayed and in effect
for a period of 60 consecutive days;

               (b) the commencement by any Borrower of a voluntary case under
the federal bankruptcy laws, as now constituted or hereafter amended, or any
other applicable federal or state bankruptcy, insolvency or other similar laws,
or the consent by any of them to the appointment of or taking possession by a
receiver, liquidator, assignee, custodian, trustee, sequestrator (or similar
official) of any Borrower or for any substantial part of their property, or the
making by any of them of any assignment for the benefit of creditors, or the
failure by any Borrower generally to pay its debts as such debts become due, or
the taking of corporate action by any Borrower in furtherance of or which might
reasonably be expected to result in any of the foregoing; or

               (c) the breach of any representation, warranty or covenant of any
Borrower contained in the Securities Purchase Agreement.

          11. Loss, Theft or Destruction of Note. Upon receipt by the Borrowers
of evidence reasonably satisfactory to it of the loss, theft or destruction of
this Note and of indemnity or security reasonably satisfactory to it, the
Company, as designated agent of the Borrowers, will make and deliver a new Note
which shall carry the same rights to interest (unpaid and to accrue) carried by
this Note, stating that such Note is issued in replacement of this Note, making
reference to the original date of issuance of this Note (and any successors
hereto) and dated as of such cancellation, in lieu of this Note.

<PAGE>
                                                                               5

          12. Definitions. As used in this Note, the following terms shall have
the following meanings:

               (a) "Affiliate" has the meaning specified in Rule 12b-2 under the
Securities Exchange Act of 1934, as amended, and the rules and regulations
promulgated thereunder.

               (b) "Borrower" and "Borrowers" have the meanings set forth in the
preamble.

               (c) "Business Day" means any day other than a Saturday, Sunday or
other day on which banks in the City of New York are required or authorized to
be closed.

               (d) "Common Stock" means the Company's common stock, par value
$.01 per share.

               (e) "Company" has the meaning set forth in the preamble.

               (f) "Default Rate" means an interest rate of fifteen percent
(15%) per annum.

               (g) "Event of Default" has the meaning set forth in Section 10.

               (h) "NASD" means the National Association of Securities Dealers,
Inc.

               (i) "Note" means this 10% Promissory Note, as may be adjusted as
provided herein.

               (j) "Payee" has the meaning set forth in the preamble.

               (k) "Person" means any natural person, firm, corporation,
propriety, public or private company, partnership, limited liability company,
public liability company, trust or other entity, and shall include any successor
(by merger or otherwise) of such entity.

               (l) "Subsidiary" and "Subsidiaries" means, individually or
collectively, (i) UTTC; (ii) NextExchange, Inc., a Delaware corporation and
wholly-owned Subsidiary of UTTC; (iii) Croix Securities, Inc., a Delaware
corporation and wholly-owned Subsidiary of UTTC; (iv) REB Securities, Inc., a
Delaware corporation and wholly-owned Subsidiary of UTTC; (v) ATG Trading, LLC,
a Delaware limited liability company and wholly owned subsidiary of the Company;
(vi) Ashton Technology Canada, Inc., a corporation subsisting under the laws of
Canada and majority owned subsidiary of the Company; and (viii) Electronic
Market Center, Inc., a Delaware corporation and majority owned subsidiary of the
Company.

               (m) "UTTC" means Universal Trading Technologies Corporation, a
Delaware corporation and Subsidiary of the Company.

<PAGE>
                                                                               6

               (n) "Voidable Transfer" has the meaning set forth in Section 5.

          13. Miscellaneous.

               (a) Notices. Any notice, request or other communications required
or permitted hereunder shall be given upon personal delivery or upon the seventh
day following mailing by registered airmail (or certified first class mail if
both the addresser and addressee are located in the United States), postage
prepaid and addressed to the parties as follows:

          To the Borrowers:

                    c/o The Ashton Technology Group, Inc.
                    1835 Market Street, Suite 420
                    Philadelphia, PA  19103
                    Attn: William W. Uchimoto, General Counsel

          with a copy to:

                    Christopher S. Auguste, Esq.
                    Jenkens & Gilchrist Parker Chapin LLP
                    The Chrysler Building
                    405 Lexington Avenue
                    New York, NY  10174

          To the Payee:

                    OptiMark Innovations Inc.
                    c/o OptiMark Holdings, Inc.
                    10 Exchange Place
                    24th Floor
                    Jersey City, NJ  07302
                    Attn:  President

or to such other single place as any single addressee shall designate by written
notice to the other addressees.

               (b) Enforcement. The Borrowers shall pay all reasonable fees and
expenses, including reasonable attorney's fees, incurred by the Payee in the
enforcement in any of the Borrowers' obligations hereunder not performed when
due.

               (c) Survival of Agreement. All covenants, agreements,
representations and warranties made by any Borrower herein shall be considered
to have been relied upon by the Payee and shall survive the making of the loan
and the execution and delivery to the Payee of this Note, regardless of any
investigation made by the Payee or on its behalf; and shall continue in full
force and effect until this Note shall terminate.

               (d) Binding Effect; Several Agreement; Successors and Assigns.
This Note shall become effective as to each Borrower when executed by such
Borrower and

<PAGE>
                                                                               7

delivered to the Payee, and thereafter shall be binding upon the Borrowers and
the Payee and their respective successors and permitted assigns, and shall inure
to the benefit of each and their respective successors and permitted assigns.

               (e) Governing Law. This Note shall be construed in accordance
with and governed by the laws of the State of New York without regard to its
conflicts of laws principles.

               (f) Waivers. No failure or delay of the Payee in exercising any
power or right hereunder shall operate as a waiver thereof, nor shall any single
or partial exercise of any such right or power, or any abandonment or
discontinuance of steps to enforce such a right or power, preclude any other or
further exercise thereof or the exercise of any other right or power. The rights
and remedies of the Payee hereunder are cumulative and are not exclusive of any
rights or remedies that they would otherwise have. No waiver of any provisions
of this Note or consent to any departure by any Borrower herefrom shall in any
event be effective unless the same shall be permitted by the last sentence of
this paragraph (f), and then such waiver or consent shall be effective only in
the specific instance and for the purpose for which given. No notice to or
demand on any Borrower in any case shall entitle such Borrower to any other or
further notice or demand in similar or other circumstances. Neither this Note
nor any provision hereof may be waived except pursuant to an agreement or
agreements, in writing entered into by the Borrowers and the Payee.

               (g) Severability. In the event any one or more of the provisions
contained in this Note should be held invalid, illegal or unenforceable in any
respect, the validity, legality and enforceability of the remaining provisions
contained herein shall not in any way be affected or impaired thereby (it being
understood that the invalidity of a particular provision in a particular
jurisdiction shall not in and of itself affect the validity of such provision in
any other jurisdiction). The parties shall endeavor in good-faith negotiations
to replace the invalid, illegal or unenforceable provisions with valid
provisions the economic effect of which comes as close as possible to that of
the invalid, illegal or unenforceable provisions.

                            [signature pages follow]

<PAGE>

          IN WITNESS WHEREOF, each Borrower has caused this Promissory Note to
be executed by its officer thereunto duly authorized.

                                        BORROWERS:

                                        COMPANY:

                                        THE ASHTON TECHNOLOGY GROUP, INC.

                                        By:/s/William W. Uchimoto
                                           ----------------------
                                        Name: William W. Uchimoto
                                        Title: EVP & General Counsel

                                        SUBSIDIARIES:

                                        UNIVERSAL TRADING TECHNOLOGIES
                                        CORPORATION

                                        By:/s/William W. Uchimoto
                                           ----------------------
                                           Name: William W. Uchimoto
                                           Title: EVP & General Counsel

                                        NEXTEXCHANGE, INC.

                                        By:/s/William W. Uchimoto
                                           ----------------------
                                           Name: William W. Uchimoto
                                           Title: EVP & General Counsel

                                        CROIX SECURITIES, INC.

                                        By:/s/ William W. Uchimoto
                                           -----------------------
                                           Name: William W. Uchimoto
                                           Title: EVP & General Counsel

                                        REB SECURITIES, INC.

                                        By:/s/William W. Uchimoto
                                           ----------------------
                                           Name: William W. Uchimoto
                                           Title: EVP & General Counsel

<PAGE>

                                        ATG TRADING, LLC

                                        By:/s/ William W. Uchimoto
                                           -----------------------
                                           Name: William W. Uchimoto
                                           Title: EVP & General Counsel

                                        ASHTON TECHNOLOGY CANADA, INC.

                                        By:/s/ William W. Uchimoto
                                           -----------------------
                                           Name: William W. Uchimoto
                                           Title: EVP & General Counsel

                                        ELECTRONIC MARKET CENTER, INC.

                                        By:/s/ Fredric W. Rittereiser
                                           ---------------------------------
                                           Name: Fredric W. Rittereiser
                                           Title: Director

<PAGE>

                                 ASSIGNMENT FORM

              (To Assign the foregoing Note, execute this form and
              supply required information.)

          FOR VALUE RECEIVED, an interest corresponding to the unpaid principal
amount of the foregoing Note and all rights evidenced thereby are hereby
assigned to

--------------------------------------------------------------------------------
                                 (Please Print)

whose address is
                ----------------------------------------------------------------

--------------------------------------------------------------------------------

Date:
      --------------------------------------------------------------------------

Payee's Signature:
                    ------------------------------------------------------------
Payee's Address:
                    ------------------------------------------------------------

                    ------------------------------------------------------------

                    ------------------------------------------------------------

Signature Guaranteed:
                    ------------------------------------------------------------

NOTE:      The signature to this Assignment Form must correspond with the name
           as it appears on the face of the Note, without alteration or
           enlargement or any change whatever, and must be guaranteed by a bank
           or trust company. Officers of corporations and those acting in a
           fiduciary or other representative capacity should file proper
           evidence of authority to assign the foregoing Note.

Source: [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00040-of-00352.parquet"}, [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00040-of-00352.parquet"}]]