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EXHIBIT 5.1
October 2, 2000
Cerus Corporation
2525 Stanwell Drive, Suite 300
Concord, CA 94520
Ladies and Gentlemen:
You have requested our opinion with respect to certain matters in connection
with the filing by Cerus Corporation (the "Company") of a Registration Statement
on Form S-3 (the "Registration Statement") with the Securities and Exchange
Commission covering the offering for resale of 1,200,000 shares of the Company's
common stock (the "Shares"), with a par value of $0.001, issued in connection
with the Purchase Agreement by and between the Company and Janus Investment Fund
on behalf of its series Janus Global Life Sciences Fund and Janus Venture Fund,
each dated August 25, 2000 (the "Purchase Agreements").
In connection with this opinion, we have examined the Registration Statement,
the Company's Certificate of Incorporation and Bylaws, as amended, the
resolutions adopted by the Board of Directors of the Company on August 24, 2000,
and such other documents, records, certificates, memoranda and other instruments
as we deem necessary as a basis for this opinion. We have assumed the
genuineness and authenticity of all documents submitted to us as originals, the
conformity to originals of all documents submitted to us as copies thereof, and
the due execution and delivery of all documents where due execution and delivery
are a prerequisite to the effectiveness thereof.
On the basis of the foregoing, and in reliance thereon, we are of the opinion
that the Shares have been validly issued, fully paid and nonassessable.
We consent to the filing of this opinion as an exhibit to the Registration
Statement and to the reference to our firm under the caption "Legal Matters" in
the Prospectus included in the Registration Statement.
Sincerely,
Cooley Godward LLP
/s/ Andrea Vachss
Andrea Vachss
