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                                                                    EXHIBIT 10.1


                        COMMON STOCK PURCHASE AGREEMENT

                                    BETWEEN

                       THE ASHTON TECHNOLOGY GROUP, INC.
                                 (THE COMPANY)

                                      AND

                          CALP II LIMITED PARTNERSHIP
                                (THE PURCHASER)



                         DATED AS OF FEBRUARY 5, 2001
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                        COMMON STOCK PURCHASE AGREEMENT

     This Common Stock Purchase Agreement (this "Agreement") is made and entered
into as of February 5, 2001 (the "Effective Date"), between The Ashton
Technology Group, Inc. (the "Company"), a Delaware corporation, and CALP II
Limited Partnership (the "Purchaser"), a Bermuda limited partnership.

                                  BACKGROUND

     The Company has authorized the issuance, sale, and delivery of 1,333,333
shares (the "Shares") of the Company's Common Stock, par value $0.01 ("Common
Stock") at a price per Share of $1.50, in currency of the United States of
America, for a total purchase price of U.S. $2,000,000. The Purchaser wishes to
purchase the Shares upon the terms and conditions stated in this Agreement. The
Purchaser is purchasing the Shares in reliance upon an exemption from the
registration requirements of Section 5 of the U.S. Securities Act of 1933, as
amended (the "Securities Act"), in reliance upon the safe harbor afforded by
Rule 903 promulgated by the U.S. Securities and Exchange Commission (the "SEC").

                                   AGREEMENT

     For and in consideration of the premises and the mutual covenants contained
herein and other good and valuable consideration, the receipt and sufficiency of
which are hereby acknowledged, the Company and the Purchaser hereby agree as
follows:

     SECTION 1. ISSUANCE AND SALE OF COMMON STOCK

     1.1. The Company agrees to issue and sell the Shares to the Purchaser and
the Purchaser agrees to purchase the Shares from the Company, at the Closing,
for the Purchase Price of U.S.$2,000,000.

     1.2. At the Closing, the Company agrees to issue and deliver to the
Purchaser a certificate for the Shares, registered in the Purchaser's name, free
and clear of any claims, and containing a legend complying with the requirements
of SEC Rule 903(b)(3)(iii)(B)(3) and the Purchaser agrees to deliver the
Purchase Price to the Company.

                                    RIDER A

     1.3. The closing of the transactions contemplated by this Agreement (the
"Closing") shall take place at a mutually agreed upon time, date and place.

     SECTION 2. PURCHASER'S REPRESENTATIONS AND WARRANTIES.

     2.1. The Purchaser represents and warrants to the Company that:

               (a) The Purchaser is not a U.S. person (a "U.S. Person") as
     defined in SEC Rule 902(k).

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               (b) The offer to sell the Shares to the Purchaser was made
     outside the United States.

               (c) The Purchaser's buy order for the Shares was made outside the
     United States.

               (d) The Purchaser has complied with all of the conditions
     required of it by SEC Regulation S in connection with its purchase of the
     Shares.

               (e) The Purchaser is acquiring the Shares for investment, and not
     with a view towards or for resale in connection with the public sale or
     distribution thereof in the United States, or to or for the account of a
     U.S. person; provided, however, that by making this representation, the
     Purchaser does not agree to hold any Shares for any minimum or other
     specific term.

               (f) The Purchaser is an "accredited investor" as that term is
     defined in Rule 501(a)(3) of Regulation D promulgated under the Securities
     Act.

                                    RIDER B

               (g) The Purchaser understands that the Shares are being offered
     and sold to it in reliance upon specific exemptions from the registration
     requirements of United States federal and state securities laws and that
     the Company is relying upon the truth and accuracy of, and the Purchaser's
     compliance with, the representations, warranties, agreements,
     acknowledgements, and understandings of the Purchaser set forth herein in
     order to determine the availability of such exemptions and the eligibility
     of the Purchaser to acquire the Shares.

               (h) The Purchaser and its advisors, if any, have been furnished
     with all materials relating to the proposed business, financial condition,
     and operations of the Company and materials relating to the offer and sale
     of the Shares, which have been requested by the Purchaser. The Purchaser
     and its advisors, if any, have been afforded the opportunity to ask
     questions of the Company; provided, however, neither such inquiries nor any
     other due diligence investigations conducted by the Purchaser or its
     advisors, if any, or its representatives shall modify, amend, or affect the
     Purchaser's right to rely on the Company's representations and warranties
     contained in Section 3 below. The Purchaser understands that its investment
     in the Shares involves a high degree of risk. The Purchaser has sought such
     accounting, legal, and tax advice as it has considered necessary to make an
     informed investment decision with respect to its acquisition of the Shares.

               (i) The Purchaser understands that no United States federal or
     state agency or any other government or governmental agency has passed on
     or made any recommendation or endorsement of the Shares, or the fairness or
     suitability of the investment in the Shares, nor have such authorities
     passed upon or endorsed the merits of the offering of the Shares.

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                                    RIDER C

               (j) The Purchaser understands that (i) the sale or re-sale of the
     Shares has not been registered under United States federal or state
     securities laws, and the Shares may not be transferred unless (a) the
     Shares are sold pursuant to an effective registration statement under the
     Securities Act, (b) the Purchaser shall have delivered to the Company an
     opinion of counsel (which opinion shall be in form, substance and scope
     customary for opinions of counsel in comparable transactions) to the effect
     that the Shares to be sold or transferred may be sold or transferred
     pursuant to an exemption from such registration, (c) the Shares are sold or
     transferred to an "affiliate" (as defined in Rule 144 promulgated under the
     Securities Act (or a successor rule) ("Rule 144")) of the Purchaser who
     agrees to sell or otherwise transfer the Shares only in accordance with
     this Section 2(j) and who is an "accredited investor" as that term is
     defined in Rule 501(a) of Regulation D promulgated under the Securities
     Act, or (d) the Shares are sold pursuant to Rule 144; (ii) any sale of such
     Shares made in reliance on Rule 144 may be made only in accordance with the
     terms of Rule 144 and further, if Rule 144 is not applicable, any re-sale
     of such Shares under circumstances in which the seller (or the person
     through whom the sale is made) may be deemed to be an underwriter (as that
     term is defined in the Securities Act) may require compliance with some
     other exemption under the Securities Act or the rules and regulations of
     the SEC thereunder; and (iii) neither the Company nor any other person is
     under any obligation to register such Shares under the Securities Act or
     any state securities laws or to comply with the terms and conditions of any
     exemption thereunder (in each case, other than pursuant to Section 4.1
     hereof). Notwithstanding the foregoing or anything else contained herein to
     the contrary, the Shares may be pledged as collateral in connection with a
     bona fide margin account or other lending arrangement.

               (k) The Purchaser understands that the Shares may bear a
     restrictive legend in substantially the following form (and a stop-transfer
     order may be placed against transfer of the certificates for such Shares:

               "The securities represented by this certificate have not been
               registered under the Securities Act of 1933, as amended. The
               securities may not be sold, transferred or assigned in the
               absence of an effective registration statement for the securities
               under said Act, or an opinion of counsel, in form, substance and
               scope customary for opinions of counsel in comparable
               transactions, that registration is not required under said Act or
               unless sold pursuant to Rule 144 under said Act."

               The legend set forth above shall be removed and the Company shall
issue a certificate without such legend to the holder of any Share upon

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which it is stamped, if, unless otherwise required by applicable state
securities laws, (a) such Share is registered for sale under an effective
registration statement filed under the Securities Act or otherwise may be sold
pursuant to Rule 144 without any restriction as to the number of securities as
of a particular date that can then be immediately sold, or (b) such holder
provides the Company with an opinion of counsel, in form, substance and scope
customary for opinions of counsel in comparable transactions, to the effect that
a public sale or transfer of such Share may be made without registration under
the Securities Act and such sale or transfer is effected, or (c) such holder
provides the Company with reasonable assurances that such Share can be sold
pursuant to Rule 144. The Purchaser agrees to sell all Shares including those
represented by a certificate(s) from which the legend has been removed, in
compliance with applicable prospectus delivery requirements, if any.

               (l) This Agreement has been duly and validly authorized,
     executed, and delivered on behalf of the Purchaser and is a valid and
     binding agreement of the Purchaser enforceable in accordance with its
     terms, subject as to enforceability to general principles of equity and to
     applicable bankruptcy, insolvency, reorganization, moratorium, liquidation,
     and other similar laws relating to, or affecting generally, the enforcement
     of applicable creditors' rights and remedies.

               (m) The Purchaser is a limited partnership organized under the
     laws of Bermuda.

               (n) The Purchaser's acquisition of the Shares is not a
     transaction (or any element of a series of transactions) that is part of a
     plan or scheme by the Purchaser to evade the registration provisions of the
     Securities Act.

     SECTION 3. REPRESENTATIONS AND WARRANTIES OF THE COMPANY

     3.1. The Company represents and warrants to the Purchaser that:

               (a) The Company is a corporation duly organized, validly
     existing, and in good standing under the laws of the State of Delaware, and
     has the requisite corporate power to own its properties and to carry on its
     business as now being conducted.

               (b) The Company has the requisite corporate power and authority
     to enter into and perform this Agreement and to issue the Shares.

               (c) The execution and delivery of this Agreement by the Company,
     and the consummation by it of the transactions contemplated hereby,
     including without limitation the issuance of the Shares, have been duly
     authorized by the Company's Board of Directors and no further consent or
     authorization is required by the Company, its Board of Directors or its
     stockholders.

               (d) This Agreement has been duly executed and delivered by the
     Company and the persons signing on behalf of the Company have full power
     and authority to do so.

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               (e) This Agreement constitutes the valid and binding obligation
     of the Company enforceable against the Company in accordance with its
     terms, except as such enforceability may be limited by general principles
     of equity or applicable bankruptcy, insolvency, reorganization, moratorium,
     liquidation, or similar laws relating to, or affecting generally, the
     enforcement of creditors' rights and remedies.

               (f) The Shares are duly authorized and, upon issuance in
     accordance with the terms hereof, shall be validly issued, fully paid, and
     nonassessable, and free from all taxes, liens, and charges with respect to
     the issue thereof.

               (g) The execution, delivery, and performance of this Agreement by
     the Company, and the consummation by the Company of the transactions
     contemplated hereby, will not (i) result in a violation of the Certificate
     of Incorporation, any Certificate of Designation applicable to any
     Preferred Stock of the Company, or the Bylaws of the Company or (ii)
     conflict with, constitute a default (or an event which with notice or lapse
     of time or both would become a default) under, or give to others any rights
     of termination, amendment, acceleration, or cancellation of, any agreement,
     indenture, or instrument to which the Company is a party, or result in a
     violation of any law, rule, regulation, order, judgment, or decree
     (including federal and state securities laws and regulations) applicable to
     the Company or by which any property or asset of the Company is bound or
     affected.

               (h) The Company acknowledges and agrees that the Purchaser is
     acting solely in the capacity of an arm's length purchaser with respect to
     this Agreement and the transactions contemplated hereby. The Company
     further acknowledges that the Purchaser is not acting as a financial
     advisor or fiduciary of the Company (or in any similar capacity) with
     respect to this Agreement or the transactions contemplated herein. The
     Company's decision to enter into this Agreement has been based solely on
     the independent evaluation by the Company and its representatives.

               (i) Neither the Company, nor any of its affiliates, nor any
     person acting on its or their behalf (i) has engaged in any form of general
     solicitation or general advertising (within the meaning of Regulation D
     under the Securities Act) in connection with the offer or sale of the
     Shares; or (ii) has directly or indirectly made any offers or sales of any
     security or solicited any offers to buy any security, under circumstances
     that would require registration of the Shares under the Securities Act or
     cause this offering of the Shares to be integrated with prior offerings by
     the Company for purposes of the Securities Act or any applicable
     stockholder approval provisions.

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               (j) The Company understands that the Purchaser is purchasing the
     Shares in reliance on the exemption from the registration requirements of
     Section 5 of the Securities Act for offshore transactions as defined in SEC
     Rule 902(h), and that the Purchaser is relying in part upon the truth and
     accuracy of, and the Company's compliance with, the representations,
     warranties, agreements, acknowledgments, and understandings of the Company
     set forth herein in order to determine the availability of such exemptions
     and the eligibility of the Company to issue and sell the Shares to the
     Purchaser without having complied with those registration requirements.
     With respect to that exemption, the Company further represents and warrants
     to the Purchaser that (i) the Company has not offered any of the Shares to
     a U.S. Person (as defined in SEC Rule 902(k)) or to a person in the United
     States; (ii) the offer and sale of the Shares to the Purchaser is being
     made in an offshore transaction as defined in SEC Rule 902(h); (iii) the
     Company has not engaged in any directed selling efforts, as defined in SEC
     Rule 902(c), with respect to the Shares; and (iv) in offering and selling
     the Shares to the Purchaser, the Company has complied with all of the
     conditions required of it under SEC Regulation S.

               (k) The Company is, and for more than the past 12 months it
     continuously has been, a "reporting company" under the Securities and
     Exchange Act of 1934, as amended (the "Exchange Act"), as defined by the
     rules and regulations of the SEC and the NASD, and has filed in a timely
     manner all reports and other information required by it to be filed with
     the SEC under the Exchange Act in order to remain a reporting company.

     SECTION 4. REGISTRATION RIGHTS

     4.1. As soon as is practicable after the Closing, the Company shall file a
registration statement (the "Registration Statement") with the SEC to register
the resale of the Shares, and shall use its best efforts to cause the
Registration Statement to become effective as soon as is reasonably practicable.
The Company shall use its best efforts to cause the registration statement to
remain effective for a period of one year from its effective date, or until the
Purchaser is no longer the owner of any Shares, whichever shall first occur.

     SECTION 5. GENERAL PROVISIONS

     5.1. This Agreement shall be governed by and interpreted in accordance with
the laws of the State of Delaware. The parties agree that the United States
District Court for the Southern District of New York, and the courts of the
State of New York located in the Borough of Manhattan, shall have exclusive
jurisdiction and venue for the adjudication of any civil action between them
arising out of relating to this Agreement, and hereby irrevocably consent to
such jurisdiction and venue.

     5.2. This Agreement may be executed in counterparts, each of which shall be
deemed an original, and all of which hall be considered one and the same
agreement.

     5.3. This agreement supersedes all other prior oral or written agreements
between the Purchaser, the Company, their affiliates and persons acting on their
behalf with respect to the issuance and sale of the Shares, and this Agreement
and the instruments referenced herein

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contain the entire understanding of the parties with respect to the matters
covered herein and therein and, except as specifically set forth herein or
therein, neither the Company nor any Purchaser makes any representation,
warranty, covenant, or undertaking with respect to such matters. No provision of
this Agreement may be waived or amended other than by an instrument in writing
signed by the party to be charged with enforcement.

     5.4. Any notices, consents, waivers, or other communications required or
permitted to be given under the terms of this Agreement must be in writing and
will be deemed to have been delivered (a) upon receipt, when delivered
personally, (b) upon receipt, when sent by facsimile, (c) three (3) days after
being sent by certified mail, return receipt requested, or (d) one (1) day after
deposit with a nationally recognized overnight delivery service, in each case
properly addressed to the party to receive the same. The addresses and facsimile
numbers for such communications shall be:

     If to the Company:                      If to the Purchaser:

     The Ashton Technology Group, Inc.       CALP II Limited Partnership
     1835 Market Street, Suite 420           c/o Forum Fund Services
     Philadelphia, Pennsylvania 19103        Washington Mall, 3rd Floor
     Facsimile: (215) ___-____               Hamilton, HM11, Bermuda
                                             Facsimile: (441) 296-1301

     5.5. This Agreement shall be binding upon and inure to the benefit of the
parties and their respective successors and assigns.

     IN WITNESS WHEREOF, the Company and the Purchaser have caused this Common
Stock Purchase Agreement to be duly executed as of the Effective Date.

THE ASHTON TECHNOLOGY GROUP, INC.       CALP II LIMITED PARTNERSHIP


By   /s/ ARTHUR J. BACCI                 By   /s/ MARK VALENTINE
     ---------------------------------        ----------------------------------
Name     Arthur J. Bacci                 Name     Mark Valentine
     ---------------------------------        ----------------------------------
Title    President and COO               Title    Chairman
     ---------------------------------        ----------------------------------


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