Ownership Submission
FORM 3
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940
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(Print or Type Responses)
1. Name and Address of Reporting Person *
  SOUTHEASTERN ASSET MANAGEMENT INC/TN/
2. Date of Event Requiring Statement (Month/Day/Year)
05/14/2012
3. Issuer Name and Ticker or Trading Symbol
CHESAPEAKE ENERGY CORP [CHK]
(Last)
(First)
(Middle)
6410 POPLAR AVENUE, SUITE 900
4. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director __X__ 10% Owner
_____ Officer (give title below) _____ Other (specify below)
5. If Amendment, Date Original Filed(Month/Day/Year)
(Street)

MEMPHIS, TN 38119
6. Individual or Joint/Group Filing(Check Applicable Line)
_X_ Form filed by One Reporting Person
___ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Beneficially Owned
1.Title of Security
(Instr. 4)
2. Amount of Securities Beneficially Owned
(Instr. 4)
3. Ownership Form: Direct (D) or Indirect (I)
(Instr. 5)
4. Nature of Indirect Beneficial Ownership
(Instr. 5)
Common Stock 87,455,895
I
Voting and/or investment discretion per investment advisory contracts

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly. SEC 1473 (7-02)
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Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 4)
2. Date Exercisable and Expiration Date
(Month/Day/Year)
3. Title and Amount of Securities Underlying Derivative Security
(Instr. 4)
4. Conversion or Exercise Price of Derivative Security 5. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 5)
6. Nature of Indirect Beneficial Ownership
(Instr. 5)
Date Exercisable Expiration Date Title Amount or Number of Shares
5.75% Cumulative Non-Voting Convertible Preferred Stock   (1) 12/31/2049 Common Stock 2,719,256 (2) $ (2) I Investment discretion per investment advisory contracts
5.75% Cumulative Non-Voting Convertible Preferred Stock (3)   (4) 12/31/2049 Common Stock 1,849,942 (5) $ (5) I Investment discretion per investment advisory contracts

Reporting Owners

Reporting Owner Name / Address Relationships
Director 10% Owner Officer Other
SOUTHEASTERN ASSET MANAGEMENT INC/TN/
6410 POPLAR AVENUE
SUITE 900
MEMPHIS, TN 38119
    X    

Signatures

/s/ Andrew R. McCarroll, General Counsel, Southeastern Asset Management, Inc. 05/22/2012
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 5(b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1) Each share of 5.75% Non-Voting Convertible Preferred Stock is convertible at any time at the option of the holder into approximately 37.037 Common Shares of Chesapeake which is based on an initial conversion price of $27.00 per Common Share, subject to certain adjustments.
(2) As of the date of this Form 3, Southeastern holds 73,420 shares of 5.75% Cumulative Non-Voting Convertible Preferred Stock. Each Preferred Share is convertible into 37.037 Common Shares of Chesapeake. The number of Common Shares issuable upon conversion of the Preferred Shares is subject to customary adjustment as set forth in the Certificate of Designations.
(3) 5.75% Cumulative Non-Voting Convertible Preferred Stock (Series A)
(4) Each share of 5.75% Cumulative Non-Voting Convertible Preferred Stock (Series A) is convertible at any time at the option of the holder into approximately 35.7961 Common Shares of Chesapeake which is based on an initial conversion price of $27.94 per Common Share, subject to certain adjustments.
(5) As of the date of this Form 3, Southeastern holds 51,680 shares of 5.75% Cumulative Non-Voting Convertible Preferred Stock (Series A). Each Preferred Share is convertible into 35.7961 Common Shares of Chesapeake. The number of Common Shares issuable upon conversion of the Preferred Shares is subject to customary adjustments as set forth in the Certificate of Designations.
 
Remarks:
Southeastern Asset Management, Inc. ("Southeastern") does not have a pecuniary interest in the securities.

As a result of a conversion from Schedule 13G to Schedule 13D filing, Southeastern may now be deemed a "beneficial owner" of more than 10% of the company's common stock for Section 16 purposes, under Rule 16a-1(a)(1).  As permitted by Rule 16a-1, this Form 3 shall not be deemed an admission that Southeastern is a beneficial owner of more than 10% of the company's common stock for Section 16 purposes.

Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, See Instruction 6 for procedure.

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