Filed by Hycor Biomedical Inc. pursuant
                                         to Rule 425 under the Securities Act of
                                         1933 and deemed filed pursuant to Rule
                                         14a-12 of the Securities Exchange Act
                                         of 1934.
                                         Subject Company: Hycor Biomedical
                                         Inc.
                                         Commission File No. 000-11647
================================================================================

FOR IMMEDIATE RELEASE

Contact:       Beckman Coulter, Inc.
               Jeanie Herbert (Investor Relations)
               714- 773-7620
               Anne M. Warde (Corporate Communications)
               714- 773-7655

               Hycor Biomedical Inc.
               Reg Jones (Senior Vice President and CFO)
               714-933-3000
               Douglas Sherk, Jennifer Cohn (EVC Group)
               415-659-2285



        HYCOR TO DEVELOP AND SUPPLY AUTOIMMUNE TESTS FOR BECKMAN COULTER
                  New Agreement to Accelerate Beckman Coulter's
                      Aggressive Menu Expansion Initiative

GARDEN GROVE and FULLERTON, Calif. - (September 23, 2003) - Hycor Biomedical
Inc. (NASDAQ: HYBD) and Beckman Coulter, Inc. (NYSE: BEC) today announced the
signing of a multi-year, exclusive, worldwide agreement under which Hycor will
develop and supply a broad menu of automated tests for certain autoimmune
disease markers on Beckman Coulter's Access(R) Immunoassay platforms including
the UniCel DxI(TM) 800 and the SYCHRON LX(R)i725. The tests, developed using
Beckman Coulter's magnetic particle chemiluminescence technology and Hycor's
library of proven antigens and antibodies, will accelerate the aggressive
immunoassay test menu expansion initiative Beckman Coulter implemented earlier
this year.

According to the American Autoimmune Related Diseases Association (AARDA), there
are more than 80 autoimmune diseases, which affect 50 million Americans, the
majority being women. Autoimmune diseases include multiple sclerosis, juvenile
diabetes, scleroderma, lupus, rheumatoid arthritis, and chronic active
hepatitis. These diseases cost more than $86 billion annually in health care
costs and are the third leading cause of death and disability, following heart
disease and cancer. Within approximately five years it is projected that the
autoimmune testing market, currently estimated at $200 million, will grow to as
high as $360 million as the testing methodology shifts, new therapeutics are
developed, and the population ages.

"By automating and consolidating autoimmune testing on our Access system, and
differentiating our menu offering through this agreement with Hycor, we have the
leverage we need to enter and take significant market share of the high volume
autoimmune disease segment," said Michael Whelan, vice president of Beckman
Coulter. "Hycor is an innovative pioneer and well established manufacturer of
autoimmune testing products and has an extensive menu of proven assays for the
clinical laboratory. Their unique competencies in the autoimmune segment of
diagnostics further strengthen our ability to impact the market."







"Many high volume clinical laboratories offer autoimmune testing using manual or
semi-manual methods," said J. David Tholen, Hycor's president and CEO. "By
partnering with major manufacturers of automated immunoassay systems, like
Beckman Coulter, we can offer our customers an extremely effective automated
immunoassay solution that will eliminate their current inefficient workstations
and expand both our and Beckman Coulter's opportunity for the sale of new
products."


About Hycor Biomedical Inc.
Hycor Biomedical Inc. discovers, develops, manufactures, and markets diagnostic
products for a variety of human medical conditions. These products include high
quality automated instrument and reagent systems that use blood samples to test
for more than 1,000 different allergies and autoimmune disorders, and urinalysis
controls and disposable products under the KOVA(R) brand, the market leader in
standardized microscopic urinalysis. Hycor products are used by physicians and
clinical laboratories all over the world to provide accurate, reliable test
results for physicians and their patients. Headquartered in Garden Grove,
California with facilities in Germany and Scotland, Hycor employs more than 140
people worldwide and serves customers in more than 50 countries. Visit Hycor
Biomedical's web site at http://www.hycorbiomedical.com.

About Beckman Coulter, Inc.
Beckman Coulter, Inc. is a leading manufacturer of instrument systems,
chemistries and supplies that simplify and automate laboratory processes. At the
forefront of medical discovery, in clinical research and through the often
life-saving process of clinical diagnostics, Beckman Coulter's 200,000 installed
systems provide essential biomedical intelligence to enhance health care around
the world. Based in Fullerton, Calif., Beckman Coulter's annual sales for 2002
totaled $2.06 billion. Sixty-two percent of this amount was generated by
recurring revenue from supplies, test kits and services. For more information,
visit www.beckmancoulter.com.

The matters discussed in this report are forward-looking statements that involve
risks and uncertainties that could cause actual results to differ materially
from the results anticipated in the forward-looking statements. These risks and
uncertainties include, but are not limited to, economic, competitive,
governmental, and technological factors affecting the Company's operations,
markets, products, services and prices, and other factors discussed in the
Company filings with the Securities and Exchange Commission.

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