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                                                                   EXHIBIT 10.39

                           TAX ALLOCATION AGREEMENT

          Agreement dated March 27, 1997, by and among The Ashton Technology
Group, Inc. (Parent) and each of its undersigned subsidiaries (Subsidiaries).

                                  WITNESSETH

          Whereas, the parties hereto are members of an affiliated group
(Affiliated Group) as defined in Section 1504(a); and

          Whereas, such Affiliated Group will file a U.S. consolidated income
tax return for its taxable year ended March 31, 1997 and is required to file
consolidated tax returns for subsequent years; and

          Whereas, it is the intent and desire of the parties hereto that a
method be established for allocating the consolidated tax liability of the
Affiliated Group among its members, for reimbursing the Parent for payment of
such tax liability, for compensating any party for use of its losses or tax
credits, and to provide for the allocation and payment of any refund arising
from a carryback of losses or tax credits from subsequent tax years.

          Now, Therefore, in consideration of the mutual covenants and promises
contained herein, the parties hereto agree as follows:

          1.   A U.S. consolidated income tax return shall be filed by the
               Parent for the tax year ended March 31, 1997, and for each
               subsequent taxable period in respect of which this Agreement is
               in effect and for which the Affiliated Group is required or
               permitted to file a consolidated tax return. Each Subsidiary
               shall execute and file such consent, elections, and other
               documents that may be required or appropriate for the proper
               filing of such returns.

          2.   For each tax period, each member of the Affiliated Group shall
               compute its tax liability in accordance with the provisions of
               Regulation (S) 1.1502-33(d)(3) with a fixed percentage of 100
               percent and shall pay such amount (including any increased
               liability allocated pursuant to such regulation above any
               liability allocated pursuant to section 1552 of the Internal
               Revenue Code) to the Parent. For purposes of this Agreement, any
               liability for alternative minimum tax shall be treated as a tax
               liability subject to this paragraph.

          3.   Payment of the consolidated tax liability for a taxable period
               shall include the payment of estimated tax installments due for
               such taxable period, and each Subsidiary shall pay to the Parent
               its share of each payment within ten days of receiving notice of
               such payment from the Parent, but in no event later than the due
               date for each such payment. Any amounts paid by a Subsidiary 
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               on account of a separate return or separate estimated tax
               payments that are credited against the consolidated tax liability
               of the Affiliated Group shall be included in determining the
               payments due from such Subsidiary. Any overpayment of estimated
               tax should be refunded to the Subsidiary. Any payments made by a
               Subsidiary to the Parent under this Agreement, including payments
               by a Subsidiary to the Parent of any estimated tax installments
               due for each taxable period, shall be paid to the Parent, even if
               the Affiliated Group as a whole does not have any consolidated
               estimated tax liability for such period.

          4.   To the extent payments received in respect of a taxable year by
               Parent pursuant to paragraph 2, above, exceed the consolidated
               tax liability for such period as a result of the absorption or
               utilization of losses, deductions, credits or similar items of
               certain members against other members' income, gain or similar
               items, then the Parent shall pay such excess amount received to
               those members whose items were absorbed or utilized in a manner
               that reasonably reflects such utilization or absorption within 10
               days of filing its consolidated federal income tax return for
               such period.

          5.   If part or all of an unused loss or tax credit is allocated to a
               member of the Affiliated Group pursuant to Regulation (S) 1.1502-
               79, and is carried back or forward to a year in which such member
               filed a separate return or a consolidated return with another
               affiliated group, any refund or reduction in tax liability
               arising from the carryback or carryover shall be retained by such
               member. Notwithstanding the above, the Parent shall determine
               whether an election shall be made not to carry back part or all
               of a consolidated net operating loss for any tax year in
               accordance with Section 172(b)(3).

          6.   If the consolidated tax liability is adjusted for any taxable
               period, whether by means of an amended return, claim for refund,
               or after a tax audit by the Internal Revenue Service, the
               liability of each member shall be recomputed to give effect to
               such adjustments, and in the case of a refund, the Parent shall
               make payment to each member for its share of the refund,
               determined in the same manner as in paragraphs 2 and 4 above,
               within ten days after the refund is received by the Parent, and
               in the case of an increase in tax liability, each member shall
               pay to the Parent its allocable share of such increased tax
               liability within ten days after receiving notice of such
               liability from the Parent.

          7.   If during a consolidated return period the Parent or any
               Subsidiary acquires or organizes another corporation that is
               required to be included in the consolidated return, then such
               corporation shall join in and be bound by this Agreement.
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          8.   This Agreement shall apply to the tax year ending March 31, 1997,
               and all subsequent taxable periods unless the Parent and the
               Subsidiaries agree to terminate the Agreement. Notwithstanding
               such termination, this Agreement shall continue in effect with
               respect to any payment or refunds due for all taxable periods
               prior to termination.

          9.   Notwithstanding any other provisions of this Agreement, payment
               of any estimated tax installment by a Subsidiary to the Parent
               under this Agreement for the tax year ending March 31, 1997 shall
               be made on or before March 31, 1997.

          10.  This Agreement shall be binding upon and inure to the benefit of
               any successor, whether by statutory merger, acquisition of
               assets, or otherwise, to any of the parties hereto, to the same
               extent as if the successor had been an original party to the
               Agreement.

          In Witness Whereof, the parties hereto have caused this Agreement to
be executed by their duly authorized representatives on March 27, 1997.


                                   THE ASHTON TECHNOLOGY GROUP, INC.

                                   By: /s/ Fredric Rittereiser   
                                      ------------------------------------------
                                        Name: Fredric W. Rittereiser   
                                        Title: President & CEO

                                   COMPUTER SCIENCE INNOVATIONS, INC.

                                   By: /s/ George Milligan      
                                      ------------------------------------------
                                        Name: George Milligan           
                                        Title: President

                                   UNIVERSAL TRADING TECHNOLOGIES
                                   CORPORATION

                                   By: /s/ Robert Eprile        
                                      ------------------------------------------
                                        Name: Robert A. Eprile          
                                        Title: President