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Exhibit 5.1
HALE AND DORR LLP
COUNSELLORS AT LAW
www.haledorr.com
The Willard Office Building
1455 Pennsylvania Avenue, N.W. . Washington, D.C. 20004-1008
202-942-8400 . fax 202-942-8484
July 28, 2000
OPNET Technologies, Inc.
3400 International Drive, N.W.
Washington, D.C. 20008
Re: Registration Statement on Form S-1
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Ladies and Gentlemen:
This opinion is furnished to you in connection with a Registration Statement
on Form S-1 (File No. 333-32588) (the "Registration Statement") filed with the
Securities and Exchange Commission (the "Commission") under the Securities Act
of 1933, as amended (the "Securities Act"), for the registration of 4,600,000
shares of Common Stock, $.001 par value per share (the "Shares"), of OPNET
Technologies, Inc., a Delaware corporation (the "Company"), including 600,000
Shares issuable upon exercise of an over-allotment option granted by the
Company.
The Shares are to be sold by the Company pursuant to an underwriting
agreement (the "Underwriting Agreement") to be entered into by and among the
Company and Morgan Stanley & Co. Incorporated, FleetBoston Robertson Stephens
Inc. and Friedman, Billings, Ramsey & Co., Inc., as representatives of the
several underwriters named in the Underwriting Agreement, the form of which has
been filed as Exhibit 1.1 to the Registration Statement.
We are acting as counsel for the Company in connection with the issue and
sale by the Company of the Shares. We have examined signed copies of the
Registration Statement as filed with the Commission. We have also examined and
relied upon the Underwriting Agreement, minutes of meetings of the stockholders
and the Board of Directors of the Company as provided to us by the Company,
stock record books of the Company as provided to us by the Company, the
Certificate of Incorporation and By-Laws of the Company, each as restated and/or
amended to date, and such other documents as we have deemed necessary for
purposes of rendering the opinions hereinafter set forth.
In our examination of the foregoing documents, we have assumed the
genuineness of all signatures, the authenticity of all documents submitted to us
as originals, the conformity to original documents of all documents submitted to
us as copies, the authenticity of the originals of such latter documents and the
legal competence of all signatories to such documents.
Boston New York Washington Reston London* Oxford*
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Hale and Dorr LLP Includes Professional Corporations *
an independent joint venture law firm
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OPNET Technologies, Inc.
July 28, 2000
Page 2
We assume that the appropriate action will be taken, prior to the offer and
sale of the Shares in accordance with the Underwriting Agreement, to register
and qualify the Shares for sale under all applicable state securities or "blue
sky" laws.
We express no opinion herein as to the laws of any state or jurisdiction
other than the state laws of the Commonwealth of Massachusetts, the General
Corporation Law of the State of Delaware and the federal laws of the United
States of America.
Based upon and subject to the foregoing, we are of the opinion that the
Shares have been duly authorized for issuance and, when the Shares are issued
and paid for in accordance with the terms and conditions of the Underwriting
Agreement, the Shares will be validly issued, fully paid and nonassessable.
It is understood that this opinion is to be used only in connection with the
offer and sale of the Shares while the Registration Statement is in effect.
Please note that we are opining only as to the matters expressly set forth
herein, and no opinion should be inferred as to any other matters. This opinion
is based upon currently existing statutes, rules, regulations and judicial
decisions, and we disclaim any obligation to advise you of any change in any of
these sources of law or subsequent legal or factual developments which might
affect any matters or opinions set forth herein.
We hereby consent to the filing of this opinion with the Commission as an
exhibit to the Registration Statement in accordance with the requirements of
Item 601(b)(5) of Regulation S-K under the Securities Act and to the use of our
name therein and in the related Prospectus under the caption "Legal Matters."
In giving such consent, we do not hereby admit that we are in the category of
persons whose consent is required under Section 7 of the Securities Act or the
rules and regulations of the Commission.
Very truly yours,
/s/ HALE AND DORR LLP
HALE AND DORR LLP
