<PAGE>
Exhibit 5.1
[Letterhead of Sonnenschein Nath & Rosenthal]
December 4, 2000
GraphOn Corporation
400 Cochrane Circle
Morgan Hill, California 95037
Re: Registration Statement on Form S-3
Under the Securities Act of 1933
Ladies and Gentlemen:
In our capacity as counsel to GraphOn Corporation, a Delaware
corporation (the "Company"), we have been asked to render this opinion in
connection with a Registration Statement on Form S-3 being filed
contemporaneously herewith by the Company with the Securities and Exchange
Commission under the Securities Act of 1933, as amended (the "Registration
Statement"), covering 300,000 shares of common stock, par value $.0001 per
share, of the Company ("Warrant Shares") that are presently issuable upon future
exercises of certain warrants heretofore issued by the Company (the "Warrants"),
all of which have been included in the Registration Statement for the account of
the persons identified therein as the Selling Stockholders.
In that connection, we have examined the Amended and Restated
Certificate of Incorporation and By-Laws of the Company, both as amended to
date, the Warrants, the Registration Statement, corporate proceedings of the
Company relating to the issuance of each of, respectively, the Warrants and the
Warrant Shares and such other instruments and documents as we have deemed
relevant under the circumstances.
In making the aforesaid examinations, we have assumed the genuineness
of all signatures and the conformity to original documents of all copies
furnished to us as original or photostatic copies. We have also assumed that the
corporate records furnished to us by the Company include all corporate
proceedings taken by the Company to date.
Based upon the subject to the foregoing, we are of the opinion that the
Warrant Shares have been duly and validly authorized and, when issued and paid
for in accordance with the terms of the Warrants and as described in the
Registration Statement, will be duly and validly issued, fully paid and
non-assessable.
We hereby consent to the use of our opinion as herein set forth as an
exhibit to the Registration Statement and to the use of our name under the
caption "Legal Matters" in the prospectus forming a part of the Registration
Statement. We do not, by giving such consent, admit that we are within the
category of persons whose consent is required under Section 7 of the Act.
Very truly yours,
SONNENSCHEIN NATH & ROSENTHAL
By: /s/ Ira Roxland
A Member of the Firm
