EXHIBIT 10.13
                                                                   -------------


                            STOCK PURCHASE AGREEMENT
                            ------------------------

                               RXBAZAAR.COM, INC.

RxBazaar.com, Inc.
1000 Winter Street
Suite 2700
Waltham, MA 02451

Ladies and Gentlemen:

     1. Purchase. Subject to the terms and conditions hereof, the undersigned
agrees to purchase the number of shares of the Common Stock, par value $.001 per
share (the "Shares"), of RxBazaar.com, Inc., a Delaware corporation (the
"Company"), set forth at the end of this Agreement, at a purchase price of $1.00
per share. The undersigned hereby tenders the amount set forth at the end of
this Agreement, in the form of a check payable to the order of the Company or
wire transfer, in full payment of the purchase price for such Shares.

     2. Closing. The sum tendered herewith pursuant to Paragraph 1 will promptly
be remitted to the Company, or third parties for the account of the Company, for
their use. Promptly after such sum is remitted to the Company or such third
parties for their use, the Company will cause a certificate for the Shares
purchased hereunder by the undersigned to be issued in the name of and delivered
to the undersigned.

     3. Acceptance of Agreement. This agreement shall be accepted by the Company
when it is signed on behalf of the Company and the funds tendered concurrently
herewith are transferred to or for the account of the Company. The Company may
refuse to accept any subscription in its sole discretion.

     4. Representations and Warranties of the Undersigned. The undersigned
hereby represents and warrants to the Company, its officers, directors, agents,
and employees as follows:

     (a) That he(1) has adequate means of providing for his current needs and
personal contingencies. He has no need now, and anticipates no need in the
foreseeable future, to sell the Shares which he hereby agrees to purchase, and
he currently has sufficient financial liquidity to afford a complete loss of his
investment in the Company.

        (b) That he has received and carefully reviewed descriptive memoranda
relating to the Company and any other materials relating thereto that he has
requested.

        (c) That he has had an opportunity to ask questions of and receive
answers from the authorized representatives of the Company, and to review any
relevant documents and
--------
1 Masculine pronouns are used solely for convenience of reference, and are
intended to have general application.
<PAGE>

records concerning the business of the Company and the terms and conditions of
this investment, and that any such questions have been answered to the full
satisfaction of the undersigned.

        (d) That no person or entity, other than the Company or its authorized
representatives, has offered the Shares to the undersigned.

        (e) That he has such knowledge and experience in financial and business
matters that he is capable of evaluating the merits and risks of an investment
in the Company, or he and his financial and investment advisors together have
such knowledge and experience in financial and business matters that they are
capable of evaluating the merits and risks of an investment in the Company.

        (f) That the Shares for which he hereby subscribes will be acquired for
his own account for investment and not with a view toward subdivision, resale,
or redistribution thereof in a manner prohibited under the Securities Act of
1933, as amended (the "Act"), and he does not presently have any reason to
anticipate any change in his circumstances or other particular occasion or event
which would cause him to sell his Shares. He has no contract, undertaking,
agreement, understanding, or arrangement with any person to sell, transfer, or
pledge to any person any part or all of the Shares for which he hereby
subscribes, or any interest therein, and has no present plans to enter into the
same.

        (g) That (i) it has been called to his attention in connection with his
investment in the Company that such investment is speculative in nature and
involves a high degree of risk, and (ii) he is aware that the Company is in the
start-up stage and thus does not have any operating history.

        (h) That he will notify the Company immediately, and in any event prior
to the date this agreement is accepted by the Company, if any event occurs which
would materially and adversely affect any of the above representations or
warranties.

        (i) That he understands that no federal or state agency has passed upon
or made any recommendation or endorsement of an investment in the Shares.

        (j) That he would come within the following categories of "accredited
investor" under Rule 501(a) of Regulation D of the Securities Exchange
Commission promulgated under the Securities Act of 1933 (Please check all
applicable spaces):

   _____    (i) His or her net worth exceeds $1,000,000 (may include spouse's
            net worth).

   _____    (ii) His or her individual income in each of the two immediately
            previous years has been more than $200,000 and his or her current
            year's income is reasonably expected to be more than $200,000, or
            his or her joint income with spouse in each of the two immediately
            previous years has been more than $300,000 and his or her current
            year's joint income is reasonably expected to be more than $300,000.

                                      -2-
<PAGE>

   _____    (iii) We are a trust with total assets of more than $5,000,000, not
            formed for the specific purpose of acquiring the Securities, whose
            purchase is being directed by an investor who, either alone or with
            his purchaser representative(s), has such knowledge and experience
            in financial affairs and business matters that he is capable of
            evaluating the merits and risks of the prospective investments.

   _____    (iv) We are an organization described in Section 501(c)(3) of the
            Internal Revenue Code, a corporation, a Massachusetts or similar
            business trust, or a partnership, not formed for the specific
            purpose of acquiring the securities, with total assets in excess of
            $5,000,000.

   _____    (v) We are a corporation or partnership and each and every of our
            equity owners falls into at least one of the above categories.

   _____    (vi) None of the above.

     5. Reliance. The undersigned acknowledges that the Company and its
officers, directors, employees, and agents are relying on the truth and accuracy
of the foregoing representations and warranties in the offering of Shares for
sale to the undersigned without having first registered the Shares under the
Act. All representations, warranties, and covenants contained in this agreement
shall survive the acceptance of this agreement and the sale of Shares in the
Company. Notwithstanding the foregoing, however, no representation, warranty,
acknowledgment, or agreement made herein by the undersigned shall in any manner
be deemed to constitute a waiver of any rights granted to him under federal or
state securities laws.

     6. Consent to Use of Information. The undersigned hereby consents to the
utilization by the Company, as necessary in connection with dealings with any
governmental and regulatory authorities, of any information supplied to the
Company by the undersigned or by his representatives in connection with the
offer and sale of the Shares, and agrees to supply any additional information
reasonably requested by any such authority.

     7. Restrictions on Transfer of Shares.

        (a) Opinion of Counsel. The undersigned acknowledges that there are
restrictions on the transferability of the Shares. Since the Shares are not
registered under the Act or applicable state securities laws, and since the
undersigned has no right to require that the Shares be so registered, the
undersigned acknowledges and agrees that he shall have no right at any time to
sell, assign, pledge, transfer, or otherwise dispose of or encumber the Shares
(except by will or by the laws of descent and distribution) unless the Company
shall first have been provided with an opinion of counsel acceptable to the
Company that such sale is exempt from such registration under the Act and any
applicable state securities laws.

        (b) Restrictive Legends. The undersigned acknowledges that each
certificate representing Shares will bear restrictive legends which may refer to
this Stock Purchase Agreement and to the restrictions on transfer referred to in
this Paragraph 7.

                                      -3-
<PAGE>

     8. Notice to Investor. Correspondence and notices to the undersigned should
be sent to the __ business __ residence address listed below until such time as
the undersigned shall notify the Company, in writing, of a different address to
which such correspondence and notices are to be sent. If neither space is marked
above, all correspondence will be sent to the undersigned's residence address.

     9. Lock-Up Provisions. In the event the Company has filed a registration
statement under the Securities Act of 1933 for an initial public offering of the
Company's Common Stock, $.001 par value (the "Common Stock"), and if in
connection therewith the Company has obtained lock-up agreements from all of its
then officers and directors not to sell any shares of Common Stock owned by them
for a specified period of time, then the undersigned shall be bound by the terms
of such agreements with respect to all shares of the Common Stock owned by the
undersigned, whether or not the undersigned has executed such an agreement. This
provision shall survive the termination of this agreement. This agreement shall
be construed as a "lock-up" agreement and may be delivered by the Company to any
underwriter retained in connection with the Company's initial public offering.

                  [remainder of page left intentionally blank]















                                      -4-
<PAGE>


     IN WITNESS WHEREOF, the undersigned has executed this Agreement as of this
___ day of ______________, 2000.

                                           -------------------------------------
                                           Signature

-------------------------------------      -------------------------------------
Business Position or Title                 Name (Typed or Printed)


-------------------------------------      -------------------------------------
Name of Business                           United States
                                           Social Security Number, if any


-------------------------------------      -------------------------------------
Business Address                           Residence Address


-------------------------------------      -------------------------------------
City, State or Province                    City, State or Province
County and Zip Code                        County and Zip Code


                                           $
-------------------------------------      -------------------------------------
Shares (#)                                 Purchase Price ($)

Accepted and agreed to:
RXBAZAAR.COM, INC.



By: _________________________

Dated: ______________________



                                      -5-