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EXHIBIT 5.1
[WILSON SONSINI GOODRICH & ROSATI LETTERHEAD]
July 20, 2000
Efficient Networks, Inc.
4849 Alpha Road
Dallas, TX 75244
Re: REGISTRATION STATEMENT ON FORM S-3
Ladies and Gentlemen:
We are acting as counsel for Efficient Networks, Inc., a Delaware
corporation (the "Company"), in connection with the registration under the
Securities Act of 1933, as amended, of $400,000,000 aggregate principal amount
of 5% Convertible Subordinated Notes due 2005 (the "Notes"), and such
indeterminate number of shares of Common Stock, $0.001 par value per share, of
the Company, as may be required for issuance upon conversion of the Notes (the
"Conversion Shares"). The Notes and the Conversion Shares are to be offered and
sold by certain securityholders of the Company. In this regard we have
participated in the preparation of a Registration Statement on Form S-3 relating
to the Notes and the Conversion Shares (such Registration Statement, as it may
be amended from time to time, is herein referred to as the "Registration
Statement").
We are of the opinion that the Notes have been duly authorized and are
binding obligations of the Company entitled to the benefits of the Indenture,
dated as of March 1, 2000, between the Company and State Street Bank and Trust
Company of California, N.A., as Trustee. We are of the further opinion that the
Conversion Shares have been duly authorized and, when issued by the Company upon
conversion of the Notes in accordance with the Indenture, will be legally
issued, fully paid and nonassessable.
We consent to the use of this opinion as an exhibit to the Registration
Statement and further consent to the use of our name wherever appearing in the
Registration Statement, including the Prospectus constituting a part thereof,
and any amendments thereto.
Sincerely,
WILSON SONSINI GOODRICH & ROSATI
Professional Corporation
/s/ Wilson Sonsini Goodrich & Rosati
Professional Corporation
