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EXHIBIT 5.1
[PIPER MARBURY RUDNICK & WOLFE LLP LETTERHEAD]
November 8, 2000
Visual Networks, Inc.
2092 Gaither Road
Rockville, Maryland 20850
Ladies and Gentlemen:
We have acted as counsel to Visual Networks, Inc., a Delaware corporation (the
"Company"), in connection with the Company's Registration Statement on Form S-3
(the "Registration Statement") filed on the date hereof with the Securities and
Exchange Commission (the "Commission") under the Securities Act of 1933, as
amended (the "Act"). The Registration Statement relates to 3,322,748 shares of
the Company's Common Stock, par value $0.01 per share (the "Shares"), which were
previously issued by the Company and are being registered for resale by the
holders thereof.
In this capacity, we have examined the Company's Certificate of Incorporation
and By-laws, the proceedings of the Board of Directors of the Company relating
to the issuance of the Shares and such other documents, instruments and matters
of law as we have deemed necessary to the rendering of this opinion. In such
examination, we have assumed the genuineness of all signatures, the authenticity
of all documents submitted to us as originals, and the conformity with originals
of all documents submitted to us as copies.
Based upon the foregoing, we are of the opinion and advise you that each of the
Shares described in the Registration Statement has been duly authorized and
validly issued and is fully paid and nonassessable. We hereby consent to the use
of our name in the Registration Statement and under the caption "Legal Matters"
in the related Prospectus and consent to the filing of this opinion as an
exhibit to the Registration Statement.
Very truly yours
/s/ Piper Marbury Rudnick & Wolfe LLP
