CombiMatrix Publishes Influenza Paper in Collaboration with World Health Organization (WHO) Laboratory after Filing Key Patent Applications.

NEWPORT BEACH, Calif. -- Acacia Research Corporation (Nasdaq:CBMX) (Nasdaq:ACTG) announced today that its CombiMatrix group paper describing the Influenza Surveillance technology has been published in the April edition of the Journal of Clinical Microbiology. This journal publishes the most-current research on microbiological aspects and diagnosis of human and animal infections and electronic versions of scientific publications can been accessed online at http://jcm.asm.org/current.dtl. The paper is titled "Use of Semiconductor-Based Oligonucleotide Microarrays for Influenza A Virus Subtype Identification and Sequencing." This research was conducted in collaboration with the U.S. Air Force Institute of Operational Health and the group of Dr. Richard J. Webby at the Infectious Diseases department of St. Jude Children's Research Hospital, chaired by Dr. Robert G. Webster.

CombiMatrix has previously applied for patents on its Influenza Surveillance technology. These patent applications were developed around and built upon CombiMatrix's microarray platform, processes, and instruments.

The CombiMatrix Influenza A Typing Microarray can identify all strains of Influenza A, including bird and human varieties. CombiMatrix's system, by tracking changes in genetic makeup of the virus, can differentiate highly pathogenic from less-lethal flu strains and can identify strains that may be resistant to drug therapy. In addition, this system can detect mixed or multiple infections of influenza. This has been identified as a critical issue for identifying infectious "carriers" of the disease, such as chickens that are able to infect others with the H5 virus but themselves have no symptoms. Information on such issues can be accessed at: http://www.cdc.gov/ncidod/EID/vol12no01/05-1024.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 arrays, which are semiconductor-based tools for use in identifying and determining the roles of genes, gene mutations and proteins. The CombiMatrix's group's technology has a wide range of potential applications in the areas of genomics, proteomics, biosensors, drug discovery, drug development, diagnostics, combinatorial chemistry, material sciences and nanotechnology.

The Acacia Technologies group develops, acquires, and licenses patented technologies. Acacia controls 42 patent portfolios, which include over 160 U.S. patents, and certain foreign counterparts, covering technologies used in a wide variety of industries including audio/video enhancement & synchronization, broadcast data retrieval, computer memory cache coherency, credit card fraud protection, database management, data encryption & product activation, digital media transmission (DMT(R)), digital video production, dynamic manufacturing modeling, enhanced Internet navigation, hearing aid ECS, image resolution enhancement, interactive data sharing, interactive television, interstitial Internet advertising, laptop docking station connectivity, microprocessor enhancement, multi-dimensional bar codes, network data storage, resource scheduling, rotational video imaging and spreadsheet automation.

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.

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