e425
Filed by Apache Corporation
Pursuant to Rule 425 of the Securities Act of 1933
and deemed filed pursuant to Rule 14a-12
of the Securities Exchange Act of 1934
Subject Company: Mariner Energy, Inc.
Commission File No. 333-166964
Update
Apache filed the S-4 registration statement related to the merger with Mariner Energy on May
19, 2010. In response to unsubstantiated reports, Apache Corporation (NYSE, Nasdaq: APA) stated
that it intends and is committed to completing the merger during the third quarter of 2010, subject
to the approval and adoption of the merger agreement by Mariner stockholders, governmental and
regulatory approvals and other usual and customary closing conditions. On May 3, 2010, the
Antitrust Division of the U.S. Justice Department and the Federal Trade Commission granted early
termination of the statutory waiting period under the Hart-Scott-Rodino Act.
Additional Information
This communication does not constitute an offer to sell or the solicitation of an offer to buy any
securities or a solicitation of any vote or approval. Apache has filed with the Securities and
Exchange Commission (SEC) a registration statement on Form S-4 containing a preliminary proxy
statement of Mariner that also constitutes a preliminary prospectus of Apache. A definitive proxy
statement/prospectus will be mailed to stockholders of Mariner. Apache and Mariner also plan to
file other documents with the SEC regarding the proposed transaction. INVESTORS AND SECURITY
HOLDERS OF MARINER ARE URGED TO READ THE DEFINITIVE PROXY STATEMENT/PROSPECTUS AND OTHER DOCUMENTS
FILED WITH THE SEC CAREFULLY AND IN THEIR ENTIRETY WHEN THEY BECOME AVAILABLE BECAUSE THEY WILL
CONTAIN IMPORTANT INFORMATION ABOUT THE PROPOSED TRANSACTION. Investors and security holders will
be able to obtain the documents (when available) free of charge at the SECs web site, www.sec.gov.
Copies of the documents filed with the SEC by Apache will be available free of charge on Apaches
website at www.apachecorp.com under the tab Investors or by contacting Apaches Investor
Relations Department at 713-296-6000. Copies of the documents filed with the SEC by Mariner will be
available free of charge on Mariners website at www.mariner-energy.com under the tab Investor
Information or
by contacting Mariners Investor Relations Department at 713-954-5558. You may also read and copy
any reports, statements and other information filed with the SEC at the SEC public reference room
at 100 F Street N.E., Room 1580, Washington, D.C. 20549. Please call the SEC at (800) 732-0330 or
visit the SECs website for further information on its public reference room.
Apache, Mariner, their respective directors and executive officers and other persons may be deemed,
under SEC rules, to be participants in the solicitation of proxies from stockholders of Mariner in
connection with the proposed transaction. Information regarding Apaches directors and officers
can be found in its proxy statement filed with the SEC on March 31, 2010, and information regarding
Mariners directors and officers can be found in its proxy statement filed with the SEC on April 1,
2010. Additional information regarding the participants in the proxy solicitation and a description
of their direct and indirect interests in the transaction, by security holdings or otherwise, will
be contained in the definitive proxy statement/prospectus and other relevant materials to be filed
with the SEC when they become available.
Forward-Looking Statements
Statements in this document include forward-looking statements within the meaning of Section 27A
of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934,
as amended. The opinions, forecasts, projections, future plans or other statements other than
statements of historical fact, are forward-looking statements. We can give no assurance that such
expectations will prove to have been correct. Actual results could differ materially as a result of
a variety of risks and uncertainties, including: the timing to consummate the proposed agreement;
the risk that a condition to closing of the proposed agreement may not be satisfied; the risk that
a regulatory approval that may be required for the proposed agreement is not obtained or is
obtained subject to conditions that are not anticipated; negative effects from the pendency of the
merger; our ability to achieve the synergies and value creation contemplated by the proposed
agreement; our ability to promptly and effectively integrate the merged businesses; and the
diversion of management time on agreement-related issues. Other factors that could materially
affect actual results are discussed in Apaches and Mariners most recent Forms 10-K as well as
each companys other filings with the SEC available at the SECs website at www.sec.gov. Actual
results may differ materially from those expected, estimated or projected. Forward-looking statements speak only as of
the date they are made, and we undertake no obligation to publicly update or revise any of them in
light of new information, future events or otherwise.