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                                                                  EXHIBIT 10.28


                               VENTRO CORPORATION
                    1500 Plymouth Street, Mt. View, CA 94043


                                November 19, 2001


DDP Ventures
P.O. Box 10845
Oakland, CA  94610-0845
Attn: David Perry

Dear David:

                  Ventro Corporation (the "Company") is pleased to offer DDP
Ventures a Net Proceeds Income Agreement ("Agreement"), as referred to in
section 2(c) of the Employment Agreement (the "Employment Agreement") between
you and the Company dated November 16, 2001, on the following terms:

                  1. COMPANY'S INVESTMENTS. As of the date of this Agreement,
the Company has invested amounts (each, an "Eligible Investment" and
collectively, "Eligible Investments") in the following companies (collectively,
"Eligible Companies"): MarketMile; DoubleTwist; Cognia; Amphire Solutions, Inc.;
Ingenuity Work, Inc.; and BioWire.com/LabVelocity, Inc. In consideration for the
Company's Eligible Investments, the Company has received securities with respect
to the Eligible Companies.

                  2. NET PROCEEDS AMOUNT. DDP Ventures shall be eligible to
receive an amount ("Incentive Proceeds") equal to 10% of the Net Proceeds Amount
of each Eligible Investment, subject to the terms of this Agreement, including
but not limited to the requirements of Section 3 of this Agreement. The Net
Proceeds Amount of each Eligible Investment is equal to the amount that the
Company receives in cash or liquid securities upon the Company's liquidation
(each, a "Liquidation Date") of each Eligible Investment, less any applicable
taxes and withholdings, brokerage commissions, attorney fees and any other
direct incremental transaction costs or other fees related to the liquidation of
each Eligible Investment, not to include Ventro employee time. The Company's
Chief Executive Officer shall determine the Net Proceeds Amount and the
Liquidation Date with respect to each Eligible Investment.

                  3. PAYMENT DATE. DPP Ventures shall be paid the Incentive
Proceeds with respect to each Eligible Investment within thirty (30) days
following the date on which the Company receives the Net Proceeds Amount with
respect to each Eligible Investment, provided that the Liquidation Date occurs
on or prior to December 31, 2003. The Incentive Proceeds shall be payable to DPP
Ventures net of applicable withholding and payroll taxes and other deductions
required by law and shall be paid by Company check or by grant of 10% of the
liquid securities in the event of an IPO or purchase for stock by a publicly
traded company. DPP Ventures shall only be eligible to receive the Incentive
Proceeds attributable to the liquidation of each Eligible Investment with a
Liquidation Date that occurred prior to the termination date of this Agreement,
<PAGE>
David Perry
[Date]
Page 2


and in no event shall DPP Ventures receive the Incentive Proceeds with respect
to the liquidation of an Eligible Investment if the Liquidation Date for such
Eligible Investment occurs after December 31, 2003.

                  4. TERM AND TERMINATION. The term of this Agreement commences
from the date of this Agreement and continues through and until December 31,
2003; provided, however, that if prior to December 31, 2003, (a) you resign from
employment with the Company or (b) the Company terminates your employment for
Cause (as defined in the Employment Agreement), then this Agreement terminates
on the effective date of your resignation or termination, respectively. As
provided in Section 6(b) of the Employment Agreement, if the Company terminates
your employment for any reason other than Cause (as defined in the Employment
Agreement) prior to December 31, 2003, then the term of this Agreement shall
still continue through and until December 31, 2003.

                  5. GENERAL ASSETS. No amounts awarded or accrued under this
Agreement shall actually be funded, set aside or otherwise segregated prior to
payment. The obligation to pay distributions shall at all times be an unfunded
and unsecured obligation of the Company. DPP Ventures shall have the status of a
general creditor and shall look solely to the general assets of the Company for
the payment of any Incentive Proceeds.

                  6. NO ALIENATION RIGHTS. DPP Ventures shall not have the right
to alienate, pledge or encumber its interest in this Agreement, and such
interest shall not (to the extent permitted by law) be subject in any way to the
claims of DPP Ventures' creditors or to attachment, execution or other process
of law.

                  7. EMPLOYMENT RELATIONSHIP. Your employment with the Company
will be "at will" and governed by the Employment Agreement referenced above.

                  8. ENTIRE AGREEMENT. This Agreement supersedes and replaces
any prior agreements, representations or understandings, whether written, oral
or implied, between DPP Ventures and the Company and between you and the Company
with respect to the subject matter described herein.

                  9. GOVERNING LAW AND SEVERABILITY. This Agreement shall be
interpreted in accordance with the laws of the State of California (except its
provisions governing the choice of law). If any provision of this Agreement
becomes or is deemed invalid, illegal or unenforceable in any applicable
jurisdiction by reason of the scope, extent or duration of its coverage, then
such provision shall be deemed amended to the minimum extent necessary to
conform to applicable law so as to be valid and enforceable or, if such
provision cannot be so amended without materially altering the intention of the
parties, then such provision shall be stricken and the remainder of this
Agreement shall continue in full force and effect. If any provision of this
Agreement is rendered illegal by any present or future statute, law, ordinance
or regulation (collectively, the "Law") then that provision shall be curtailed
or limited only to the minimum extent necessary to bring the provision into
compliance with the Law. All the other
<PAGE>
David Perry
[Date]
Page 3


terms and provisions of this Agreement shall continue in full force and effect
without impairment or limitation.

                  10. NO ASSIGNMENT. This Agreement and all of DPP Ventures'
rights and obligations hereunder are specific to DPP Ventures and may not be
transferred or assigned by DPP Ventures at any time. The Company may assign its
rights under this Agreement to any entity that assumes the Company's obligations
hereunder in connection with any sale or transfer of all or a substantial
portion of the Company's assets to such entity.

                  11. ARBITRATION.

                  (a) SCOPE OF ARBITRATION REQUIREMENT. The parties hereby waive
their rights to a trial before a judge or jury and agree to arbitrate before a
neutral arbitrator any and all claims or disputes arising out of this Agreement.

                  (b) PROCEDURE. The arbitrator's decision shall be written and
shall include the findings of fact and law that support the decision. The
arbitrator's decision shall be final and binding on both parties, except to the
extent applicable law allows for judicial review of arbitration awards. The
arbitrator may award any remedies that would otherwise be available to the
parties if they were to bring the dispute in court. The arbitration shall be
conducted in accordance with the National Rules for the Resolution of Employment
Disputes of the American Arbitration Association; provided, however, that the
arbitrator shall allow the discovery authorized by the California Arbitration
Act or that the arbitrator deems necessary for the parties to vindicate their
respective claims or defenses. The arbitration shall take place in Santa Clara
County, California or, at the option of DPP Ventures, the county in which DPP
Ventures primarily conducted business with the Company at the time when the
arbitrable dispute or claim first arose.

                  (c) COSTS. The parties shall share the costs of arbitration
equally, except that the Company shall bear the cost of the arbitrator's fee and
any other type of expense or cost that DPP Ventures would not be required to
bear if DPP Ventures were to bring the dispute or claim in court. Both DPP
Ventures and the Company shall be responsible for their own attorneys' fees, and
the arbitrator may not award attorneys' fees unless a statute or contract at
issue specifically authorizes such an award.

                  (d) APPLICABILITY. This arbitration provision does not apply
to the following: (a) workers' compensation or unemployment insurance claims or
(b) claims concerning the validity, infringement or enforceability of any trade
secret, patent right, copyright or any other trade secret or intellectual
property held or sought by either DPP Ventures or the Company (whether or not
arising under the Company's Employee Confidentiality Agreement between you and
the Company).
<PAGE>
David Perry
[Date]
Page 2


                  12. COUNTERPARTS. This Agreement may be executed in two or
more counterparts, each of which shall be deemed an original, but all of which
together shall constitute one and the same instrument.

                                    * * * * *

                  DPP Ventures may indicate agreement with these terms and
accept the terms of this Agreement by signing and dating the enclosed duplicate
original of this Agreement and returning it to me.

                  If you have any questions, please call me at 650.567.8900.


                                           Very truly yours,

                                           VENTRO CORPORATION



                                           By:  /s/Ted Drysdale
                                                -------------------------------
                                           Title:       President & CEO
                                                 ------------------------------



I have read and accept this Agreement:



    /s/ David Perry
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         Signature of David Perry

Dated:   11/19/01
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