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EXHIBIT 5.1
Vinson & Elkins L.L.P.
Attorneys at Law
2300 First City Tower
1001 Fannin Street
Houston, Texas 77002-6760
Telephone (713) 758-2222
Fax (713) 758-2346
January 12, 2001
ATP Oil & Gas Corporation
4600 Post Oak Place, Suite 200
Houston, Texas 77027
Ladies and Gentlemen:
We have acted as counsel for ATP Oil & Gas Corporation, a Texas corporation
(the "Company"), in connection with the proposed offer and sale (the "Offering")
by the Company to the several underwriters (the "Underwriters") set forth in the
underwriting agreement (the "Underwriting Agreement") to be executed in
connection with the Offering among the Company and the representatives of the
Underwriters, pursuant to the prospectus forming a part of a Registration
Statement on Form S-1, File No. 333-46034, originally filed with the Securities
and Exchange Commission on September 18, 2000, as amended by Amendment No. 1
filed December 12, 2000 and Amendment No. 2 filed January 4, 2001 (such
Registration Statement, as amended at the effective date thereof, being referred
to herein as the "Registration Statement"), of an aggregate of 7,500,000 shares
of Common Stock, par value $.001 per share, of the Company ("Common Stock).
Capitalized terms used but not defined herein have the meanings set forth in the
Registration Statement.
We are rendering this opinion as of the time the Registration Statement
becomes effective in accordance with Section 8(a) of the Securities Act of 1933,
as amended.
In connection with this opinion, we have assumed that the Registration
Statement, and any amendments thereto (including post-effective amendments),
will have become effective and the shares of Common Stock will be issued and
sold in compliance with applicable federal and state securities laws and in the
manner described in the Registration Statement and the applicable prospectus.
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ATP Oil & Gas Corporation
Page 2
January 12, 2001
In connection with the opinion expressed herein, we have examined, among
other things, the Restated Articles of Incorporation and the Amended and
Restated Bylaws of the Company, the records of corporate proceedings that have
occurred prior to the date hereof with respect to the Offering, the Registration
Statement, as amended and the form of Underwriting Agreement to be executed
among the Company, Lehman Brothers Inc., CIBC World Markets Corp., Dain Rauscher
Incorporated, Raymond James & Associates, Inc. and Fidelity Capital Markets, a
division of National Financial Services LLC, as representatives of the several
Underwriters. We have also reviewed such questions of law as we have deemed
necessary or appropriate.
Based upon the foregoing, we are of the opinion that the shares of Common
Stock proposed to be issued and sold by the Company to the Underwriters have
been validly authorized for issuance and, upon the issuance and delivery thereof
as set forth in the Registration Statement, will be validly issued, fully paid
and nonassessable
This opinion is limited in all respects to the laws of the State of Texas,
as interpreted by the courts of the State of Texas and the Federal courts.
We hereby consent to the statements with respect to us under the heading
"Legal Matters" in the prospectus forming a part of the Registration Statement
and to the filing of this opinion as an exhibit to the Registration Statement,
but we do not thereby admit that we are within the class of persons whose
consent is required under the provisions of the Securities Act of 1933, as
amended, or the rules and regulations of the Securities and Exchange Commission
issued thereunder.
Very truly yours,
/s/ VINSON & ELKINS L.L.P.
VINSON & ELKINS L.L.P.
