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EXHIBIT 5
September 25, 2000
Ariba, Inc.
1565 Charleston Road
Mountain View, California 94043
Re: Ariba, Inc. (the "Company")
Registration Statement for
an aggregate of 1,700,000 Common Stock
Ladies and Gentlemen:
We refer to your registration on Form S-8 (the "Registration
Statement") under the Securities Act of 1933, as amended, of 1,700,000 shares of
Common Stock available for issuance under the Company's SupplierMarket.com, Inc.
1999 Stock Option Plan. We advise you that, in our opinion, when such shares
have been issued and sold pursuant to the applicable provisions of the
SupplierMarket, Inc. 1999 Stock Option Plan and in accordance with the
Registration Statement, such shares will be validly issued, fully paid and
nonassessable shares of Ariba, Inc.'s Common Stock.
We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement.
Very truly yours,
/s/ Gunderson Dettmer Stough
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Villeneuve Franklin & Hachigian, LLP
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Gunderson Dettmer Stough Villeneuve Franklin &
Hachigian, LLP
