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EXHIBIT 5.1
[COOLEY GODWARD LLP LETTERHEAD]
October 2, 2000
Rigel Pharmaceuticals, Inc.
240 East Grand Avenue
South San Francisco, CA 94080
Ladies and Gentlemen:
You have requested our opinion with respect to certain matters in connection
with the filing by Rigel Pharmaceuticals, Inc. (the "Company") of a Registration
Statement on Form S-1 (the "Registration Statement") with the Securities and
Exchange Commission (the "Commission") covering the underwritten public offering
of up to 10,350,000 shares of common stock, including 9,000,000 shares to be
sold by the Company (the "Company Shares") and 1,350,000 shares for which the
Underwriters have been granted an over-allotment option (together with the
Company Shares, the "Common Stock").
In connection with this opinion, we have (i) examined and relied upon the
Registration Statement and related Prospectus, the Company's Amended and
Restated Certificate of Incorporation and Bylaws and the originals or copies
certified to our satisfaction of such records, documents, certificates,
memoranda and other instruments as in our judgment are necessary or appropriate
to enable us to render the opinion expressed below and (ii) assumed that the
shares of the Common Stock will be sold by the Underwriters at a price
established by the Pricing Committee of the Company's Board of Directors.
On the basis of the foregoing, and in reliance thereon, we are of the opinion
that the Common Stock, when sold and issued in accordance with the Registration
Statement and related Prospectus, will be validly issued, fully paid and
nonassessable.
We consent to the reference to our firm under the caption "Legal Matters" in the
Prospectus included in the Registration Statement and to the filing of this
opinion as an exhibit to the Registration Statement.
Very truly yours,
Cooley Godward LLP
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*By: /s/ SUZANNE SAWOCHKA HOOPER
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Suzanne Sawochka Hooper, Esq.
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