FOR IMMEDIATE RELEASE

HERCULES, CA – July 15, 2003 – Bio-Rad Laboratories, Inc. (AMEX: BIO and BIO.B), a multinational manufacturer and distributor of life science research products and clinical diagnostics announced today that it has received approval from the United States Department of Agriculture (USDA) to sell its TeSeE® test kit, the company’s second generation test kit used for the detection of Chronic Wasting Disease (CWD) in deer and elk. This CWD test kit is the only one of its kind. It runs on an automated robotics platform that speeds up sample preparation, enabling laboratories to provide faster results. Technicians using this new testing platform can process up to 1000 samples per day.

Validation data collected from a study led by Dr. Barbara Powers of Colorado State University Veterinary Diagnostic Laboratory, Fort Collins, showed that the test kit performed successfully when compared to the immunohistochemistry (IHC) test. The benefit of the new Bio-Rad test is that it offers the same level of sensitivity as the IHC method, but more samples can be tested in a shorter amount of time and with fewer technicians than IHC. The IHC method takes three to five days to obtain results, whereas the Bio-Rad test can be completed in less than five hours.

“We are pleased to be able to provide this new platform to laboratories conducting CWD testing and hope that it will assist them in their efforts to meet the increasing demand for rapid testing,” said Norman Schwartz, Bio-Rad President and CEO.

This new CWD test is based on the same proven technology as Bio-Rad’s first generation CWD test, which was approved by the USDA in October 2002. The test uses the ELISA (enzyme-linked immunosorbent assay) method to detect the abnormal prion protein associated with Chronic Wasting Disease and is reported to be the fastest and the easiest method to adapt to mass screening programs. Bio-Rad’s first generation CWD test was used to screen deer and elk samples during the 2002 hunting season.

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.