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                       SECURITIES AND EXCHANGE COMMISSION

                             WASHINGTON, D.C. 20549


                                    FORM 8-K


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


    Date of Report (Date of earliest event reported)   September 13, 2000.


                               COMMERCE ONE, INC.
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             (Exact name of registrant as specified in its charter)


                Delaware            000-26453           68-0322810
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     (State or other jurisdiction  (Commission         (IRS Employer
           of incorporation)       File Number)      Identification No.)


                4440 Rosewood Drive, Pleasanton, California 94588
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            (Address of principal executive offices)      (Zip Code)


      Registrant's telephone number, including area code   (925) 520-6000


                                       N/A
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          (Former name or former address, if changed since last report)


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ITEM 2.  ACQUISITION OR DISPOSITION OF ASSETS

         On June 20, 2000, Commerce One, Inc., a Delaware corporation
("Commerce One") entered into an Agreement and Plan of Reorganization and
Merger, dated June 20, 2000 (the "Merger Agreement"), by and among Commerce
One, Constitution Acquisition Corporation, a Delaware corporation and
wholly-owned subsidiary of Commerce One ("Merger Sub"), and AppNet, Inc., a
Delaware corporation ("AppNet"). On September 13, 2000, according to the
terms of the Merger Agreement, Merger Sub merged with and into AppNet, with
AppNet as the surviving corporation (the "Merger"). The Merger was
consummated by the filing of a Certificate of Merger with the Secretary of
State of the State of Delaware. As a result of the Merger, AppNet became a
wholly-owned subsidiary of Commerce One. The Merger is a tax-free
reorganization under the Internal Revenue Code of 1986, as amended, and is
being accounted for as a purchase transaction.

         Under the terms of the Merger, each share of AppNet common stock
issued and outstanding immediately prior to the closing of the Merger was
cancelled and converted automatically into the right to receive 0.8 of a
share of Commerce One common stock. In addition, the Merger Agreement
provided that at the closing of the Merger, each issued and outstanding
option or right to purchase AppNet common stock, whether or not exercisable,
was assumed by Commerce One. Each stock option or right continued to have the
same terms and conditions as it had immediately prior to the closing of the
merger, except that each option or right became an option or right to
purchase a number of shares of Commerce One common stock equal to 0.8
multiplied by the number of shares of AppNet common stock subject to such
option or right. No fractional shares of Commerce One common stock will be
issued pursuant to the Merger, but instead cash equal to the market value of
the fractional shares will be paid.

         Under the terms of the Merger, approximately 27.9 million shares of
Commerce One common stock will be exchanged for all outstanding shares of
AppNet common stock, and approximately 6.5 million shares of Commerce One
common stock have been set aside as a reserve for the assumption of
outstanding options and rights to purchase AppNet common stock. The terms of
the Merger were determined by arms-length negotiations.

         The description contained in this Item 2 of the transactions
contemplated by the Merger Agreement is qualified in its entirety by
reference to the full text of the Merger Agreement, a copy of which is
incorporated by reference hereto as Exhibit 2.1.

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ITEM 7.  FINANCIAL STATEMENTS, PRO FORMA FINANCIAL INFORMATION AND EXHIBITS.

         (a)   FINANCIAL STATEMENTS

         Commerce One will provide the financial statements required by
paragraph (a) of Item 7 of Form 8-K promulgated by the Commission pursuant to
the Securities Exchange Act of 1934, as amended (the "Exchange Act"), within
60 days after the date that the initial report on this Form 8-K must be filed.

         (b)   PRO FORMA FINANCIAL INFORMATION

         Commerce One will provide the pro forma financial information
required by paragraph (b) of Item 7 of Form 8-K promulgated by the Commission
pursuant to the Exchange Act within 60 days after the date that the initial
report on this Form 8-K must be filed.

         (c)   EXHIBITS

               2.1  Agreement and Plan of Reorganization, dated June 20, 2000 by
                    and among Commerce One, Inc., Constitution Acquisition
                    Corporation and AppNet, Inc. (incorporated by reference to
                    Exhibit 2.1 to the Current Report on Form 8-K filed by
                    Commerce One, Inc. on June 29, 2000 (File No. 000-26453))


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                                    SIGNATURE

         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 hereunto duly authorized.


                                             COMMERCE ONE, INC.


                                             /s/ Robert M. Tarkoff
                                             --------------------------------
                                             Robert M. Tarkoff
                                             Senior Vice President, Corporate
                                             Development and General Counsel

                                             Date:  September 27, 2000



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                                INDEX TO EXHIBITS
<TABLE>
<CAPTION>
    Exhibit No.     Description
    -----------     -----------
<S>                 <C>
        2.1         Agreement and Plan of Reorganization, dated June 20, 2000 by
                    and among Commerce One, Inc., Constitution Acquisition
                    Corporation and AppNet, Inc. (incorporated by reference to
                    Exhibit 2.1 to the Current Report on Form 8-K filed by
                    Commerce One, Inc. on June 29, 2000 (File No. 000-26453))
</TABLE>