SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

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                                    FORM 8-K

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

                                 APRIL 27, 2005
                DATE OF REPORT (DATE OF EARLIEST EVENT REPORTED)

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                           ACACIA RESEARCH CORPORATION
             (Exact name of Registrant as specified in its Charter)


         Delaware                      000-26068                95-4405754
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(State or Other Jurisdiction          (Commission              (I.R.S. Employer
       of Incorporation)              File Number)           Identification No.)

                            500 Newport Center Drive,
                         Newport Beach, California 92660
                    (Address of Principal Executive Offices)

                                 (949) 480-8300
                    Registrant's telephone number, including
                                    area code

                                 Not Applicable
          (Former Name or Former Address, if Changed since Last Report)



ITEM 2.02.   RESULTS OF OPERATIONS AND FINANCIAL CONDITION.

         On April 27, 2005, Acacia Research Corporation issued a press release
announcing its earnings for the three months ended March 31, 2005. A copy of
that release is furnished as Exhibit 99.1 to this report.

         The information in this Current Report on Form 8-K is being furnished
and shall not be deemed "filed" for the purposes of Section 18 of the Securities
Exchange Act of 1934, as amended, or otherwise subject to the liabilities of
that Section. The information in this Current Report shall not be incorporated
by reference into any registration statement or other document pursuant to the
Securities Act of 1933, as amended, except as shall be expressly set forth by
specific reference in such filing.

ITEM 9.01.   FINANCIAL STATEMENTS AND EXHIBITS.

         (c)      Exhibits.

                  99.1  Press Release dated April 27, 2005 of the Registrant.


                                   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.


                                ACACIA RESEARCH CORPORATION


Date:  April 27, 2005           By:  /s/ Paul R. Ryan
                                     -------------------------------------------
                                     Name: Paul R. Ryan
                                     Title: Chairman and Chief Executive Officer


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                                  Exhibit Index


Exhibit Number            Description
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   99.1                   Press Release dated April 27, 2005, of the Registrant.