<DOCUMENT>
<TYPE>EX-23.4
<SEQUENCE>5
<FILENAME>acacia_s3a2ex23-4.txt
<TEXT>

<PAGE>

                                                                    EXHIBIT 23.4


            CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

We hereby consent to the incorporation by reference in this Registration
Statement on Form S-3/A of our report dated March 14, 2005 relating to the
financial statements of CombiMatrix Group (a division of Acacia Research
Corporation), which appears in Acacia Research Corporation's Annual Report on
Form 10-K for the year ended December 31, 2004. We also consent to the reference
to us under the heading "Experts" in such Registration Statement.

PRICEWATERHOUSECOOPERS LLP

Los Angeles, California
May 2, 2005


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</DOCUMENT>