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EXHIBIT 99.1


  ACACIA
 RESEARCH
CORPORATION


                                                         Contacts: Bret L. Undem
                                                                 Media Relations
                                                             Tel. (425) 493-2293
                                                             Fax. (425) 493-2010

FOR RELEASE
-----------
October 4, 2004

                COMBIMATRIX ENTERS INTO AGREEMENT TO ACQUIRE 33%
                   OF ONCOLOGY DRUG DEVELOPER LEUCHEMIX, INC.
              Company Continues Expansion in Drug Development Arena

         Newport Beach, Calif. - (BUSINESS WIRE) -October 4, 2004 - Acacia
Research Corporation (Nasdaq: CBMX:ACTG) announced today that its Combimatrix
group has entered into an agreement to acquire one third ownership of Leuchemix,
Inc., a private drug development firm which is developing several compounds for
the treatment of leukemia and other cancers. In consideration for the equity
ownership, CombiMatrix will provide Leuchemix, a total of $4 million, paid
quarterly over the next two years.

         The equity will be in the form of preferred stock, and Dr. Amit Kumar,
CombiMatrix's CEO will become a director of Leuchemix.

         Leuchemix is developing a series of small molecules that have shown
efficacy against various Leukemias and solid tumors in animal models. These
molecules are designed to be cytotoxic to cancerous cells as well as to
precursors of such cells. The first indication will be Acute Myelogenous
Leukemia (AML), which is a malignant disease of the bone marrow. Additional
indications addressed will be other hematological diseases such as Chronic
Myelogenous Leukema, Myeloma and Lymphoma. Animal efficacy has also been shown
for solid tumors such as breast and prostate cancer.

         Dr. William Matthews, President and CEO of Leuchemix stated, "Leuchemix
is delighted to close its Series A financing and looks forward to a strong
relationship with Combimatrix. This equity funding will allow us to accelerate
our drug descovery programs with our initial goal being to file our first IND in
2005."

         "We are pleased to be involved with Leuchemix. This transaction
demonstrates our continued expansion into the drug development arena," stated
Dr. Amit Kumar, President and CEO of CombiMatrix. "We look forward to progress
at Leuchemix, and we will seek to utilize CombiMatrix's capabilities and
products in aiding Leuchemix whenever possible."

         Dr. Kumar added, "While we are very excited about the prospects of the
DNA Microarray, Biodefense, and Nanotechnology thrusts of our business, we
continue to see tremendous opportunities to invest in drug development. External
investment in firms such as Leuchemix, will complement the internal efforts we
have undertaken in the area of siRNA drug discovery and development. We are
pleased to be executing on our strategy with this transaction which will provide
us with a significant ownership position in a promising company."

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         The key co-founder and CEO of Leuchemix, William Matthews, was formerly
the co-founder and CEO of Deltagen Corporation, and previously a research
scientist at Genentech. In addition to Dr. Matthews and Dr. Kumar, the Board of
Directors of Leuchemix is comprised of Dr. Roger Whiting, formerly an executive
at Roche Bioscience and Syntex, and currently President and Chief Scientific
Officer at Roxro Pharmaceuticals, and Dr. Chris Henney formerly the CEO of
Dendreon (NASDAQ: DNDN), and a co-founder of ICOS (NASDAQ:ICOS) and a co-founder
of Immunex (acquired by Amgen in 2002 for $16 billion).


ABOUT ACACIA RESEARCH COPORATION

Acacia Research Corporation comprises two operating groups: Acacia Technologies
Group and CombiMatrix Group.

The CombiMatrix group is developing a platform technology to rapidly produce
customizable active biochips, which are semiconductor-based tools for use in
identifying and determining the roles of genes, gene mutations and proteins.
CombiMatrix's technology has a wide range of applications including DNA
synthesis/diagnostics, siRNA synthesis, drug discovery, and immunochemical
detection. CombiMatrix provides DNA arrays to researchers under the
CustomArray(TM) brand. CombiMatrix's Express Track(sm) drug discovery program is
a systems biology approach, using its technology, to target common viral
diseases with siRNA compounds.

The Acacia Technologies group develops, acquires, and licenses patented
technologies. Acacia's DMT(R) technology, which is supported by 5 U.S. and 31
foreign patents, relates to audio and audio/video transmission and receiving
systems commonly known as audio-on-demand, video-on-demand, and audio/video
streaming, and is used for distributing digital content via several means
including Internet, cable, satellite and wireless systems. Acacia's Internet
Access Redirection ("IAR") technology covers redirected Internet registrations
commonly used at wireless hotspots and hotels.

Acacia Research-Acacia Technologies (Nasdaq: ACTG) and Acacia
Research-CombiMatrix (Nasdaq: CBMX) are both classes of common stock issued by
Acacia Research Corporation and are intended to reflect the performance of the
respective operating groups and are not issued by the operating groups.

Information about the Acacia Technologies Group and the CombiMatrix Group is
available at www.acaciaresearch.com.


SAFE HARBOR STATEMENT UNDER THE PRIVATE SECURITIES LITIGATION REFORM ACT OF
1995:

THIS NEWS RELEASE CONTAINS FORWARD-LOOKING STATEMENTS WITHIN THE MEANING OF THE
"SAFE HARBOR" PROVISIONS OF THE PRIVATE SECURITIES LITIGATION REFORM ACT OF
1995. THESE STATEMENTS ARE BASED UPON OUR CURRENT EXPECTATIONS AND SPEAK ONLY AS
OF THE DATE HEREOF. OUR ACTUAL RESULTS MAY DIFFER MATERIALLY AND ADVERSELY FROM
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AND UNCERTAINTIES, INCLUDING THE ECONOMIC SLOWDOWN AFFECTING TECHNOLOGY
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