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January 10, 2001
EXHIBIT 5.1
Ciphergen Biosystems, Inc.
6611 Dumbarton Circle
Fremont, CA 94555
RE: REGISTRATION STATEMENT ON FORM S-8
Ladies and Gentlemen:
We have examined the Registration Statement on Form S-8 to be filed by
you with the Securities and Exchange Commission on or about January 10, 2001
(the "Registration Statement"), in connection with the registration under the
Securities Act of 1933, as amended, of 1,507,216 shares of your Common Stock
under your 1993 Stock Option Plan, of 1,075,000 shares of your Common Stock
under the 2000 Stock Plan; and of 215,000 shares of your Common Stock under the
2000 Employee Stock Purchase Plan. Such shares of Common Stock are referred to
herein as the "Shares" and such plans are referred to herein as the "Plans". As
your counsel in connection with this transaction, we have examined the
proceedings taken and are familiar with the proceedings proposed to be taken by
you in connection with the issuance and sale of the Shares pursuant to the
Plans.
It is our opinion that, when issued and sold in the manner described in
the Plans and pursuant to the agreements that accompany each grant under the
Plans, the Shares will be legally and validly issued, fully-paid and
non-assessable.
We consent to the use of this opinion as an exhibit to the Registration
Statement, and further consent to the use of our name wherever appearing in the
Registration Statement and any amendment thereto.
Very truly yours,
WILSON SONSINI GOODRICH & ROSATI
Professional Corporation
/s/ Wilson Sonsini Goodrich & Rosati
