<PAGE>
                                                                   EXHIBIT 10.28


                                AMENDMENT # 3 TO
                     MAJOR ACCOUNT LICENSE AGREEMENT BETWEEN
                      GE MEDICAL SYSTEMS AND SELECTICA INC.

This Amendment #3 ("Amendment #3") to the Major Account License Agreement
between GE Medical Systems and Affiliates ("Customer") and Selectica Inc.
("SELECTICA") dated June 28, 2002 (the "Agreement"), is made as of the date of
signature by the last signing party (the "Effective Date") by and among Customer
and SELECTICA.

                                     RECITAL

On June 28, 2002, Customer and SELECTICA entered into the Agreement by which
SELECTICA is to provide certain Services. The parties to the Agreement now wish
to amend the Agreement as follows by executing this Amendment #3.

                                    AGREEMENT

1.    Exhibit B, Section 3, Paragraph 3 (Payment Schedule Table) of the
      Agreement, shall be deleted in its entirety and replaced with the
      following:

<TABLE>
<CAPTION>
                    Payment Date                        Amount of Payment
                    ------------                        -----------------
<S>                                                     <C>
       Acceptance of Deliverable at Milestone 1            $ 2,760,000
       (estimated September 30, 2002)

       Acceptance of Deliverable at Milestone 2            $ 2,760,000
       (estimated December 31, 2002)

       "Gold Code" for Field Release R1+                   $ 1,693,000
       (estimated March 31, 2003)

       "Gold Code" for Field Release R2+                   $ 1,219,000
       (estimated June 30, 2003)

       "Gold Code" for Field Release R3+                   $ 1,105,000
       (estimated September 30, 2003)

       "Gold Code" for Field Release R4+                   $ 1,105,000
       (estimated December 31, 2003)

       Field Deployment of R4+ to GEMS Core                $ 1,579,000
       (estimated February 15, 2004)

       Field Deployment (50%) of R4+ to GEMS Core          $ 1,579,000
       (estimated March 31, 2004)

        TOTAL                                              $13,800,000
</TABLE>

      Customer agrees to issue the purchase orders approximately forty-five(45)
days prior to the acceptance date. Selectica shall invoice to the Customer
approximately thirty (30) days

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prior to the acceptance date and cash payments shall be made once acceptance has
been received.

2.    Miscellaneous

All other terms and conditions of the Agreement, including exhibits and
schedules remain unchanged.

This Amendment #3 may be executed in any number of counterparts, each of which
shall be deemed an original, but all of which together shall constitute one
instrument.

In the event of any inconsistency between the terms of the Agreement and the
terms of this Amendment, this Amendment will prevail in all respects.

This Amendment #3, prior Amendments #1 and #2, and the Major Account License
Agreement constitute the entire agreement, and supercedes any and all prior
agreements between SELECTICA and Customer relating to the Software,
Documentation, services and other items subject to this Agreement.

IN WITNESS WHEREOF, the parties have caused this Amendment #3 to the Agreement
to be duly signed and authorized.

GE Medical Systems                         SELECTICA, INC.
(CUSTOMER)                                 (SELECTICA)

By:    /s/ RONALD J. MAUER                 By:    /s/ Stephen Bennion
    ----------------------------               ----------------------------
Name:  RONALD J. MAUER                     Name:  Stephen Bennion
      --------------------------                 --------------------------
Title: SOURCING LEADER                     Title: CFO
       -------------------------                  -------------------------
Address:                                   Address:
         -----------------------                    -----------------------

--------------------------------           --------------------------------
Date:  28 - Mar 03                         Date:  3-31-03
      --------------------------                 --------------------------