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EXHIBIT 5
August 10, 2000
Chiron Corporation
4560 Horton Street
Emeryville, California 94608
Re: Chiron Corporation
REGISTRATION STATEMENT FOR OFFERING OF SHARES OF COMMON STOCK
Ladies and Gentlemen:
In connection with your registration of Ten Million (10,000,000) shares of
the Common Stock of Chiron Corporation (the "Company") on Form S-8 under the
Securities Act of 1933, as amended, I advise you that, in my opinion, when
such shares have been issued and sold pursuant to the provisions of the
Chiron 1991 Stock Option Plan, and in accordance with the Registration
Statement, such shares will be duly authorized, validly issued, fully paid
and non-assessable shares of the Company's Common Stock.
I hereby consent to filing of this opinion as an exhibit to the Registration
Statement.
Very truly yours,
/s/ William G. Green
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William G. Green
Senior Vice President and
General Counsel
