HERCULES, Calif., November 4, 2002 – Bio-Rad Laboratories, Inc. (AMEX: BIO and BIO.B), a multinational manufacturer and distributor of life science research products and clinical diagnostics announced today it has received a veterinary biological permit from the United States Department of Agriculture (USDA) for its rapid test used for the detection of chronic wasting disease (CWD) in mule deer. Bio-Rad’s CWD test is the first commercial test kit to be approved by the USDA. As part of the validation process, the Bio-Rad test was used successfully in Colorado to provide wildlife managers and hunters with fast, accurate results. Other state laboratories throughout the country may soon be able to conduct similar surveillance and screening programs using the Bio-Rad test.

“We have been working closely with the USDA and state diagnostic labs to validate our rapid CWD test and make it accessible to other state labs as soon as possible,” said Norman Schwartz Bio-Rad vice president and manager of Life Science. “Now that it has been approved, we can quickly provide the tests to all states and government approved laboratories seeking immediate assistance in their screening and surveillance programs.”

Bio-Rad’s test for detecting CWD in deer and elk is based on a proven technology referred to as the ELISA (enzyme-linked immunosorbent assay) method. It is the most widely used TSE (transmissible spongiform encephalopathy) screening test in the world and is highly regarded in the scientific community for its sensitivity, accuracy and ease-of-use Bio-Rad Lends Its Experience To Colorado’s CWD Testing Program

The State of Colorado selected Bio-Rad’s rapid CWD test for use in its statewide screening program. Wildlife officials expect to test up to 50,000 hunter-killed animals during the 2002 hunting season. Under the direction of Dr. Barbara Powers, Director of the Colorado State University Diagnostic Laboratory, three state labs are performing tests on peripheral tissues—lymphoid (retropharyngeal lymph node) and/or brain (obex) tissue—harvested from the bodies of hunter-killed deer. The Colorado initiative to conduct field validation trials using the Bio-Rad test began in August and was made possible through a cooperative effort among various state agencies including the Colorado Division of Wildlife, the Colorado State University Veterinary Diagnostic Laboratory, the Colorado Department of Agriculture, as well as the Colorado Veterinary Medical Association and hunters. Since then, Dr. Powers and her staff have performed more than 7,000 tests and compared results to the immunohistochemistry method. The Bio-Rad CWD test successfully identified all positive animals.

Bio-Rad Receives USDA Permit

Bio-Rad worked closely with Colorado officials to establish this program in less than one month’s time.

The company has extensive experience in deploying large-scale TSE screening programs throughout Europe and Japan. With Bio-Rad’s CWD test, Colorado laboratories can quickly screen samples and produce results in just five hours—faster than most testing methods.

Bio-Rad Laboratories, Inc. (www.bio-rad.com) is a multinational manufacturer and distributor of life science research products and clinical diagnostics. It is based in Hercules, California, and serves more than 70,000 research and industry customers worldwide through a network of more than 30 wholly owned subsidiary offices.

Various statements made within this press release may constitute “forward-looking statements” for purposes of the Securities and Exchange Commission’s “safe harbor” provisions under the Private Securities Litigation Reform Act of 1995 and Rule 3b-6 under the Securities Exchange Act of 1934. The forward-looking statements contained herein involve risks and uncertainties that could cause results to differ materially from the Company’s expectations.

For more information, contact: Ron Hutton, Treasurer Bio-Rad Laboratories, Inc. (510) 724-7000 [email protected] Roger Villareal Benjamin | Weber Shandwick (415) 352-2628 [email protected]