<PAGE>

================================================================================
                                 UNITED STATES
                      SECURITIES AND EXCHANGE COMMISSION
                            Washington, D.C. 20549

                             --------------------

                                  FORM 10-K/A
                               (Amendment No. 1)
[X]  ANNUAL REPORT PERSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE
     ACT OF 1934
                  For the fiscal year ended December 31, 2000

                                      OR

[ ]  TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES
     EXCHANGE ACT OF 1934

                       Commission File Number: 000-25375
                             VIGNETTE CORPORATION
            (Exact name of registrant as specified in its charter)


                Delaware                                   74-2769415
     (State or other jurisdiction of                    (I.R.S. Employer
     incorporation or organization)                    Identification No.)


                     901 South MoPac Expressway, Bldg III
                             Austin, Texas  78746
                   (Address of principal executive offices)

                             --------------------

                                (512) 741-4300
             (Registrant's telephone number, including area code)

                             --------------------

       Securities registered pursuant to Section 12(b) of the Act: None

          Securities registered pursuant to Section 12(g) of the Act:

                         Common Stock, $0.01 par value
                             (Title of each class)

                             --------------------

   Indicate by check mark whether the registrant (1) has filed all reports
required to be filed by Sections 13 or 15(d) of the Securities Exchange Act of
1934 during the preceding 12 months (or for such shorter period that the
registrant was required to file such reports), and (2) has been subject to such
filing requirements for the past 90 days

  (1)  Yes [X]    No [ ]
  (2)  Yes [X]    No [ ]

   Indicate by check mark if disclosure of delinquent filers pursuant to Item
405 of Regulation S-K is not contained herein, and will not be contained, to the
best of registrant's knowledge, in definitive proxy or information statements
incorporated by reference in Part III of this Form 10-K or any amendment to this
Form 10-K

   As of January 31, 2001, the aggregate market value of the voting stock held
by non-affiliates of the registrant was approximately $1,472,497,222.

   As of January 31, 2001, there were 240,148,465 shares of the Registrant's
common stock outstanding.

                             --------------------

                      DOCUMENTS INCORPORATED BY REFERENCE

   None.
================================================================================
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PORTION AMENDED

The Registrant hereby amends Part IV - Item 14 (a)(3), "Exhibits" of the
"Exhibits, Financial Statement Schedules and Reports on Form 10-K," contained in
the Registrant's Report on Form 10-K for the year ended December 31, 2000 to
provide detail of Exhibits 10.18 through 10.25 and to add Exhibit 21.1. Except
as set forth in Item 14 (a)(3) below, no other changes are made to the Company's
Report on Form 10-K for the year ended December 31, 2000.

                                       2
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(a)(3) Exhibits

<TABLE>
<C>         <S>
Exhibit
-------
Number                                             Description
------      ----------------------------------------------------------------------------------------------
 2.1*       Agreement between Registrant and Diffusion, Inc. dated May 10, 1999.
 2.2**      Agreement between Registrant and DataSage, Inc. dated January 7, 2000.
 2.3****    Agreement and Plan of Merger, among Registrant, Wheels Acquisition Corp. and OnDisplay, Inc.
            dated May 21, 2000.
 3.1+       Certificate of Incorporation of the Registrant.
 3.2***     Amendment to Certificate of Incorporation.
 3.3+       Bylaws of the Registrant.
 4.1        Reference is made to Exhibits 3.1, 3.2. and 3.3
 4.2+       Specimen common stock certificate.
 4.3+       Fifth Amended and Restated Registration Rights Agreement dated November 30, 1998.
10.1+       Form of Indemnification Agreements.
10.2+       1995 Stock Option/Stock Issuance Plan and forms of agreements thereunder.
10.3+       1999 Equity Incentive Plan.
10.4+       Employee Stock Purchase Plan.
10.5+       1999 Non-Employee Directors Option Plan.
10.6+       Security and Loan Agreement dated March 24, 1998 between the Registrant and Imperial Bank.
10.7+       Lease Agreement dated September 20, 1996 between the Registrant and David B. Barrow, Jr.
10.8+       First Supplement to Lease Agreement dated November 4, 1997 between Registrant and 3410 Far
            West, Ltd.
10.9+       Second Supplement to Lease Agreement dated February 23, 1998 between Registrant and 3410
            Far West, Ltd.
10.10+      Office Lease Agreement date August 4, 1998 between Registrant and B.O. III, Ltd.
10.11+      "Prism" Development and Marketing Agreement dated July 19, 1996 between the Registrant and
            CNET, Inc.
10.12+      Letter Amendment to "Prism" Development and Marketing Agreement between the Registrant and
            CNET, Inc. dated August 15, 1998 and attachments thereto.
10.13+      Software License Agreement dated April 6, 1998 between Registrant and Net Perceptions, Inc.
10.14+      StoryServer Q2 Volume Purchase Agreement between Registrant and Tribune Interactive Inc.
10.15+      Protege Software (Holdings) Confidential Professional Services Agreement dated November 15,
            1997.
10.16+      Subordinated Loan and Security Agreement dated December 3, 1998 between Registrant and
            Comdisco, Inc.
10.17+      Master Lease Agreement dated December 3, 1998 between Registrant and Comdisco, Inc.
10.18       Lease Agreement dated March 3, 2000 between the Registrant and Prentiss Properties Acquisition
            Partners, L.P.
10.19       First Amendment to Lease Agreement dated September 1, 2000 between the Registrant and Prentiss
            Properties Acquisition Partners, L.P.
10.20       Sublease dated June 26, 2000 among the Registrant, Aptis, Inc. and Billing Concepts Corp.
10.21       First Amendment to Lease dated October 30, 1998 between the Registrant and B.O. III, Ltd.
10.22       Second Amendment to Lease dated December 30, 1998 between the Registrant and B.O. III, Ltd.
10.23       Third Amendment to Lease dated April 27, 1999 between the Registrant and The Prudential
            Insurance Company of America (successor in interest to B.O. III, Ltd.).
10.24       Fourth Amendment to Lease dated August 1, 2000 between the Registrant and The Prudential
            Insurance Company of America (successor in interest to B.O. III, Ltd.).
10.25       Fifth Amendment to Lease dated December 12, 2000 between the Registrant and The Prudential
            Insurance Company of America (successor in interest to B.O. III, Ltd.).
21.1        Subsidiaries of the Registrant.
23.1        Consent of Independent Auditors.
</TABLE>
_________
+    Incorporated by reference to the Company's Registration Statement on Form
     S-1, as amended (File No. 333-68345).
*    Incorporated by reference to the Company's Form 8-K filed on July 15, 1999
     (File No. 000-25375).
**   Incorporated by reference to the Company's Form 8-K filed on February 29,
     2000 (File No. 000-25375).
***  Incorporated by reference to the Company's definitive Proxy Statement for
     Special Meeting of

                                       3
<PAGE>

     Stockholders, dated February 17, 2000.
**** Incorporated by reference to the Company's Registration Statement on Form
     S-4, as amended (File No. 333-38478).

                                       4
<PAGE>

                                  SIGNATURES

   Pursuant to the requirements of the Securities Exchange Act of 1934, the
Registrant has duly caused this report to be signed on its behalf by the
undersigned thereunto duly authorized.

                                   Vignette Corporation
                                    (Registrant)





                                       By: /s/ Gregory A. Peters
                                          ------------------------------------
                                               Gregory A. Peters
                                            Chief Executive Officer



Dated: March 30, 2001

   Pursuant to the requirements of the Securities Exchange Act of 1934, this
report has been signed below by the following persons in the capacities and on
the dates indicated:


         Signature                          Title                     Date
         ---------                          -----                     ----

  /s/  Gregory A. Peters          Chairman of the Board           March 30, 2001
----------------------------      and Chief Executive Officer
       Gregory A. Peters


    /s/  Joel G. Katz             Secretary and Chief Financial   March 30, 2001
----------------------------      Officer
         Joel G. Katz


   /s/  Robert E. Davoli          Director                        March 30, 2001
----------------------------
        Robert E. Davoli


   /s/  Joseph A. Marengi         Director                        March 30, 2001
----------------------------
        Joseph A. Marengi


 /s/  Steven G. Papermaster       Director                        March 30, 2001
----------------------------
      Steven G. Papermaster


   /s/  John D. Thornton          Director                        March 30, 2001
----------------------------
        John D. Thornton

                                       5