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MANAGEMENT’S REPORT ON INTERNAL CONTROL OVER FINANCIAL REPORTING
It is the responsibility of the management of Chesapeake Energy Corporation to establish and maintain
adequate internal control over financial reporting (as defined in Rule 13a-15(f) under the Securities Exchange
Act of 1934). Management utilized the Committee of Sponsoring Organizations of the Treadway Commission’s
Internal Control-Integrated Framework (COSO framework) in conducting the required assessment of
effectiveness of the company’s internal control over financial reporting.
Management has performed an assessment of the effectiveness of the company’s internal control over
financial reporting and has determined the company’s internal control over financial reporting was effective as
of December 31, 2010.
The effectiveness of the company’s internal control over financial reporting as of December 31, 2010 has
been audited by PricewaterhouseCoopers LLP, an independent registered public accounting firm, as stated in
its report which appears herein.
/s/ AUBREY K. MCCLENDON
Aubrey K. McClendon
Chairman of the Board and Chief Executive
Officer
/s/ DOMENIC J. DELL’OSSO, JR.
Domenic J. Dell’Osso, Jr.
Executive Vice President and Chief Financial
Officer
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