EXHIBIT 5.1
[Letterhead of PIPER MARBURY RUDNICK & WOLFE LLP]
September 20, 2000
The Board of Directors
VASCO Data Security International, Inc.
1901 South Meyers Road, Suite 210
Oakbrook Terrace, Illinios 60181
Re: Registration Statement on Form S-3
Gentlemen:
We have acted as counsel to VASCO Data Security International, Inc., a
Delaware corporation (the "Company"), with respect to the Company's Registration
Statement on Form S-3 filed with the Securities and Exchange Commission under
the Securities Act of 1933, as amended (the "Act"), relating to the offer and
sale of up to 4,561,855 shares (the "Shares") of the Company's Common Stock, par
value $.001 per share, which may be offered and sold from time to time by
certain selling securityholders named in the Prospectus contained in the
Registration Statement or in amendments or supplements thereto. As counsel for
the Company, we have examined the Registration Statement, and originals or
copies, certified or otherwise identified to our satisfaction, of such other
documents, corporate records, certificates of public officials and other
instruments as we have deemed necessary for the purposes of rendering this
opinion. In our examination, we have, with your approval, assumed the
genuineness of all signatures, the authenticity of all documents submitted to us
as originals and the conformity with the originals of all documents submitted to
us as copies. As to various questions of fact material to such opinion, we have
relied, to the extent we deemed appropriate, upon representations, statements
and certificates of officers and representatives of the Company and others. We
have not independently verified such information or assumptions. Based upon,
subject to and limited by the foregoing and the other qualifications herein, we
are of the opinion that the Shares have been duly authorized for issuance by the
Company and are validly issued, fully paid and non-assessable. We consent to the
use of this opinion as an exhibit to the Registration Statement, and we consent
to the use of our name under the caption "Legal Matters" in the Prospectus
forming a part of the Registration Statement. In giving this consent, we do not
admit that we come within the category of persons whose consent is required
under Section 7 of the Act or the rules promulgated thereunder.
Very truly yours,
/s/ Piper Marbury Rudnick & Wolfe LLP
PIPER MARBURY RUDNICK & WOLFE LLP
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