CombiMatrix to Webcast Presentation at the Lehman Brothers Seventh Annual Global Healthcare Conference.

Business Editors/Health/Medical Writers

BIOWIRE2K

NEWPORT BEACH, Calif.--(BUSINESS WIRE)--Feb. 27, 2004

Acacia Research Corporation (Nasdaq:CBMX)(Nasdaq:ACTG) announced today that its CombiMatrix group will present at the Lehman Brothers Seventh Annual Global Healthcare Conference at the Loews Miami Beach Hotel, located in Miami, Florida. Dr. Amit Kumar, President and CEO of CombiMatrix will present an overview of the company.

A live transmission of the presentation will take place at 2:00 pm ET on Wednesday, March 3, 2004. An archived webcast will be available for 30 days. To access the live webcast or archived presentation, please go to www.combimatrix.com/news_events.htm.

ABOUT ACACIA RESEARCH CORPORATION

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 initial focus of Express Track(SM)
includes the following viral diseases:

Virus                               Collaborator
SARS                                NIAID/USAMRIID
HIV type 1                          irsiCaixa - Dr. Bonaventura Clotet
HIV type 2                          To Be Announced
West Nile virus                     To Be Announced
Human Papillomavirus type 16        To Be Announced
Human Herpes 8 (Kaposi's sarcoma)   To Be Announced
Smallpox (Variola)                  To Be Announced
Influenza virus A                   To Be Announced
Influenza virus B                   To Be Announced
Hepatitis C                         To Be Announced

   CombiMatrix is also establishing applications of its arrays
through other partnerships as follows:

Project                             Collaborator
Cancer Diagnosis (Lymphoma)         University of Washington/Rational
                                        Diagnostics
RNA Drug Targets                    Professor Gregory L. Verdine,
                                        Harvard University

Parasite
Leishmania                          Seattle Biomedical Research
                                        Institute
Trypasonoma                         Seattle Biomedical Research
                                        Institute

The Acacia Technologies Group develops, acquires, and licenses patented technologies. Acacia's DMT 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 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 those expressed in any forward-looking statements as a result of various factors and uncertainties, including the recent economic slowdown affecting technology companies, our ability to successfully develop products, rapid technological change in our markets, changes in demand for our future products, legislative, regulatory and competitive developments and general economic conditions. Our Annual Report on Form 10-K, recent and forthcoming Quarterly Reports on Form 10-Q, recent Current Reports on Forms 8-K and 8-K/A, and other SEC filings discuss some of the important risk factors that may affect our business, results of operations and financial condition. We undertake no obligation to revise or update publicly any forward-looking statements for any reason.