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EXHIBIT 5.1
August 29, 2000
Pharsight Corporation
800 West El Camino Real, Suite 200
Mountain View, California 94040
Ladies and Gentlemen:
You have requested our opinion with respect to certain matters in connection
with the filing by Pharsight Corporation (the "Company") of a Registration
Statement on Form S-8 (the "Registration Statement") with the Securities and
Exchange Commission covering the offering of up to 6,932,905 shares of the
Company's Common Stock, $.001 par value, (the "Shares") pursuant to its 2000
Equity Incentive Plan, 2000 CEO Non-Qualified Stock Option Plan, 1997 Stock
Option Plan and 1995 Stock Option Plan (the "Plans").
In connection with this opinion, we have examined the Registration Statement,
your Restated and Amended Certificate of Incorporation and By-laws, as amended,
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, when sold and issued in accordance with the Plan, the
Registration Statement and related Prospectus, will be validly issued, fully
paid, and nonassessable (except as to shares issued pursuant to certain deferred
payment arrangements, which will be fully paid and nonassessable when such
deferred payments are made in full).
We consent to the filing of this opinion as an exhibit to the Registration
Statement.
Very truly yours,
COOLEY GODWARD LLP
By: /s/ Brett D. White
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Brett D. White
