
<PAGE>

                      SECURITIES AND EXCHANGE COMMISSION
                            WASHINGTON, D.C. 20549

                           ________________________

                                  FORM 8-K/A
                                AMENDMENT NO. 1

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

        Date of Report (date of earliest event reported): June 18, 1999


                              ACTUATE CORPORATION
            (Exact name of registrant as specified in its charter)


         Delaware                      0-24607                  94-3193197
         --------                      -------                  ----------
(State or other jurisdiction         (Commission             (I.R.S. Employer
     of incorporation)               File Number)           Identification No.)



             999 Baker Way, Suite 270 San Mateo, California 94404
         (Address of principal executive offices, including zip code)

      Registrant's telephone number, including area code: (650) 425-2300

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                              Actuate Corporation

                               Table of Contents



  Item 7.  Financial Statements and Exhibits...........................   3


  Signatures ..........................................................   5
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Item 7.  Financial Statements and Exhibits.

          (a)  Financial Statements of Business Acquired

          Included as Exhibit 99.01 hereto, and incorporated herein by
reference, is a copy of the audited consolidated financial statements of Actuate
Holdings, B.V. ("Actuate BV") as of December 31, 1998 and 1997 and for each of
the years ended December 31, 1998 and 1997.

          Included as Exhibit 99.02 hereto, and incorporated herein by
reference, is a copy of certain unaudited consolidated condensed financial
statements of Actuate BV as of June 18, 1999 and for the period from January 1,
1999 to June 18, 1999 (date of acquisition) and six months ended June 30, 1998.
The unaudited consolidated condensed financial statements of Actuate BV are
incomplete as they were prepared solely for purposes of preparing pro forma
condensed consolidated statements of operations data and do not include all of
the information required by Regulation S-X for the full quarterly financial
statements, such as footnotes.

          (b)  Pro Forma Financial Statements

          Included as Exhibit 99.03 hereto, and incorporated herein by
reference, is a copy of the pro forma condensed combined consolidated financial
information with respect to the acquisition of Actuate BV by us (the
"Acquisition"), which combines Actuate Corporation's ("Actuate") statement of
operations for the fiscal year ended December 31, 1998, six months ended June
30, 1999 and six months ended June 30, 1998 with Actuate BV's statements of
operations for fiscal year ended December 31, 1998, for the period from January
1, 1999 to June 18, 1999 (date of acquisition) and six months ended June 30,
1998, respectively, as if the acquisition had occurred on January 1, 1998.

          (c)  Exhibits:

          The following exhibits are filed herewith:

           Exhibit   Description
           -------   -----------

            2.1      Form of Stock Purchase Agreement dated June 4, 1999, among
                     Actuate Corporation, Actuate Holding B.V. and the
                     stockholders of Actuate Holding B.V.*

          23.01      Consent of Ernst & Young Entrepreneurs, Independent
                     Auditors

          99.01      Audited Consolidated Financial Statements of Actuate BV as
                     of December 31, 1998 and 1997, and for the years ended
                     December 31, 1998 and 1997.

          99.02      Unaudited condensed consolidated balance sheet as of June
                     18, 1999 and statements of operations and cash flows for
                     the period
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                     from January 1, 1999 to June 18, 1999 and six months ended
                     June 30, 1998.

          99.03      Pro forma condensed consolidated combined statement of
                     operations information for the six months ended June 30,
                     1999 and 1998 and for the fiscal year ended December 31,
                     1998.

__________________________
* Previously filed.
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                                  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 hereunto duly authorized.


                                        Actuate Corporation


Date:  August 27, 1999                  /s/  William P. Garvey
                                        ---------------------------------
                                        William P. Garvey
                                        General Counsel
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                                 EXHIBIT INDEX



          Exhibit   Description
          -------   -----------

            2.1     Form of Stock Purchase Agreement dated June 4, 1999, among
                    Actuate Corporation, Actuate Holding B.V. and the
                    stockholders of Actuate Holding B.V.*

          23.01     Consent of Ernst & Young Entrepreneurs, Independent Auditors

          99.01     Audited Consolidated Financial Statements of Actuate BV as
                    of December 31, 1998 and 1997, and for the years ended
                    December 31, 1998 and 1997.

          99.02     Unaudited condensed consolidated balance sheet as of June
                    18, 1999 and statements of operations and cash flows for the
                    period from January 1, 1999 to June 18, 1999 and six months
                    ended June 30, 1998.

          99.03     Pro forma condensed consolidated combined statement of
                    operations information for the six months ended June 30,
                    1999 and 1998 and for the fiscal year ended December 31,
                    1998.

____________________________
*  Previously filed.
