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EXHIBIT 5.1
August 4, 2000
CyberSource Corporation
1295 Charleston Road
Mountain View, California 94043
Ladies and Gentlemen:
We have examined the Registration Statement on Form S-8 to be filed by
CyberSource Corporation, a Delaware corporation (the "Company"), with the
Securities and Exchange Commission on August 4, 2000 (the "Registration
Statement"), relating to the registration under the Securities Act of 1933, as
amended, of 4,137,500 shares of the Company's Common Stock, $0.001 par value
(the "Shares"). The Shares are reserved for issuance pursuant to the Company's
1999 Stock Option Plan, 1999 Non-Qualified Stock Option Plan and a Restricted
Stock Purchase Right. As counsel to the Company, we have examined the
proceedings taken by the Company in connection with the registration of the
Shares.
It is our opinion that the Shares, when issued and sold in the manner
described in the Registration Statement and the related Prospectus, will be
legally and validly issued, fully paid and nonassessable.
We consent to the use of this opinion as an exhibit to the
Registration Statement and further consent to all references to us in the
Registration Statement and any amendments thereto.
Very truly yours,
/S/ Morrison & Forester LLP
