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EXHIBIT 5.1
July 20, 2000
Commerce One, Inc.
4440 Rosewood Drive
Pleasanton, CA 94588
RE: REGISTRATION STATEMENT ON FORM S-4
Ladies and Gentlemen:
We have examined the Registration Statement on Form S-4 to be filed by you
with the Securities and Exchange Commission on or about July 20, 2000 (the
"Registration Statement") in connection with the registration under the
Securities Act of 1933, as amended, of shares of your Common Stock (the
"Shares"). As your counsel in connection with this transaction, we have examined
the proceedings taken and are familiar with the proceedings proposed to be taken
by you in connection with the issuance of the Shares pursuant to the acquisition
transaction set forth and described in the Registration Statement.
It is our opinion that, when issued in the manner described in the
Registration Statement, the Shares will be validly issued, fully-paid and
non-assessable.
We consent to the use of this opinion as an exhibit to the Registration
Statement, and further consent to the use of our name whenever appearing in the
Registration Statement and any amendments thereto.
Very truly yours,
WILSON SONSINI GOODRICH & ROSATI
Professional Corporation
/s/ WILSON SONSINI GOODRICH & ROSATI
