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EXHIBIT 5.1
[COOLEY GODWARD LLP LETTERHEAD]
September 29, 2000
Siebel Systems, Inc.
1855 South Grant Street
San Mateo, CA 94402
Re: Form S-3
Ladies and Gentlemen:
You have requested our opinion with respect to certain matters in connection
with the filing by Siebel Systems, Inc. (the "Company") of a Registration
Statement on Form S-3 (the "Registration Statement") with the Securities and
Exchange Commission (the "Commission") covering the proposed issuance and sale
from time to time of 9,565,837 shares of the Company's common stock (the
"Shares").
In connection with this opinion, we have examined the Registration Statement,
the Company's Amended and Restated Certificate of Incorporation and Bylaws, each
as amended to date, 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.
Our opinion is expressed only with respect to the federal laws of the United
States of America, the General Corporation Law of the State of Delaware and the
laws of the State of California. We express no opinion as to whether the laws of
any particular jurisdiction other than those identified above are applicable to
the subject matter hereof.
On the basis of the foregoing, and in reliance thereon, we are of the opinion
that when issued, the shares of common stock that may be sold pursuant to the
Registration Statement 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.
Sincerely,
Cooley Godward LLP
By: /s/ Keith A. Flaum
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Keith A. Flaum
