Exhibit 5.1
September 5, 2006
ManTech International Corporation
12015 Lee Jackson Highway
Fairfax, VA 22033
| RE: | Registration Statement on Form S-8 |
Ladies and Gentlemen:
We refer to the above-captioned Registration Statement on Form S-8 (the “Registration Statement”) filed by ManTech International Corporation., a Delaware corporation (the “Company”), with the Securities and Exchange Commission under the Securities Act of 1933, as amended (the “Act”), relating to 5,000,000 shares of the Company’s Class A Common Stock, par value $0.01 per share (the “Shares”), authorized and reserved for issuance under the Management Incentive Plan of ManTech International Corporation, 2006 Restatement (the “Plan”). This opinion is being furnished in accordance with the requirements of Item 601(b)(5) of Regulation S-K under the Act. This opinion relates to 1,287,963 Shares available for issuance due to automatic increases from 2002 until 2005 under the terms of the Plan, 1,500,000 additional Shares authorized by the 2006 restatement of the Plan and up to 2,212,037 additional shares that may become available for issuance due to automatic increases from 2006 until 2012 under the terms of the Plan.
In connection with this opinion, we have examined the originals or certified copies of such corporate records, certificates of officers of the Company and/or public officials and such other documents and have made such other factual and legal investigations as we have deemed relevant and necessary as the basis for the opinions set forth below. In such examination, 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 certified or photostatic copies and the authenticity of the originals of such copies.
In making our examination of documents executed or to be executed by parties other than the Company, we have assumed that such parties had or will have the power, corporate or other, to enter into and perform all obligations thereunder and have also assumed the due authorization by all requisite action, corporate or other, and execution and delivery by such parties of such documents and the validity and binding effect thereof. As to any facts material to the opinions expressed herein which we have not independently established or verified, we have relied upon oral or written statements and representations of officers and other representatives of the Company and others.
Based upon and subject to the foregoing, we are of the opinion that, subject to the future operation of the automatic increase provisions of the Plan as to 2,212,037 of the Shares, the Shares have been duly authorized and when the Shares have been issued, delivered and paid for upon exercise of options duly granted pursuant to the terms of the Plan, such Shares will be validly issued, fully paid and nonassessable.
We understand that this opinion is to be used in connection with the Company Registration Statement on Form S-8 relating to the Stock to be filed with the Securities and Exchange Commission under the Act.
The opinions expressed in this letter are solely for your information and use, and no other person may rely upon or otherwise use the opinions for any purpose without our express written consent.
| Very truly yours, |
| /s/ McGuireWoods LLP |
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