8-A12B

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-A

For Registration of Certain Classes of Securities

Pursuant to Section 12(b) or (g) of the

Securities Exchange Act of 1934

CHESAPEAKE ENERGY CORPORATION

(Exact name of registrant as specified in its charter)

Oklahoma	73-1395733
(State of incorporation or organization)	(IRS Employer Identification No.)

6100 North Western Avenue, Oklahoma City, Oklahoma	73118
(Address of principal executive offices)	(Zip Code)

Securities to be registered pursuant to Section 12 (b) of the Act:

Title of each class to be registered	Name of each exchange on which each class is to be registered
6.25% Mandatory Convertible Preferred Stock	New York Stock Exchange

If this form relates to the registration of a class of securities pursuant to Section 12(b) of the Exchange Act and is effective pursuant to General Instruction A.(c), check the following box. x

If this form relates to the registration of a class of securities pursuant to Section 12(g) of the Exchange Act and is effective pursuant to General Instruction A.(d) check the following box. o

Securities Act registration statement file number to which this form relates: N/A

Securities to be registered pursuant to Section 12(g) of the Act: None

Item 1. Description of Registrant’s Securities to be Registered.

The securities to be registered consist of 6.25% Mandatory Convertible Preferred Stock, par value $.01 and liquidation preference $250 per share (the "Preferred Stock"), of Chesapeake Energy Corporation (the "Registrant"). The Registrant hereby incorporates by reference herein the description of the terms, rights and preferences of the Preferred Stock set forth under the caption "Description of Preferred Stock" in the Prospectus Supplement dated June 27, 2006 to the Prospectus dated December 8, 2005 forming a part of the Registrant’s registration statement on Form S-3 (No. 333-130196). Such Prospectus, as supplemented, was filed with the Commission by the Registrant pursuant to Rule 424(b)(5) under the Securities Act of 1933 on June 28, 2006.

Item 2. Exhibits.

The following exhibits are filed pursuant to the Instruction to Item 2:

Exhibit No.	Description
1.	Registrant’s Restated Certificate of Incorporation, as amended. Incorporated herein by reference to Exhibit 3.1.1 to Registrant’s Form 10-Q for the quarter ended March 31, 2005. Amendment to Registrant’s Restated Certificate of Incorporation dated June 14, 2006. Incorporated herein by reference to Exhibit 3.1.1 to Registrant’s Form 8-K dated June 15, 2006.
2.	Registrant’s Certificate of Designation for Series A Junior Participating Preferred Stock, as amended. Incorporated herein by reference to Exhibit 3.1.2 to the Registrant’s Form 10-Q for the quarter ended March 31, 2005. Third Amendment to the Certificate of Designation for Series A Junior Participating Preferred Stock. Incorporated herein by reference to Exhibit 3.1.2 to Registrant’s Form 8-K dated June 15, 2006.
3.	Registrant’s Certificate of Designation for 5.0% Cumulative Convertible Preferred Stock (Series 2003), as amended. Incorporated herein by reference Exhibit 3.1.4 to Registrant’s Form 10-K for the year ended December 31, 2005. Certificate of Elimination for 5.0% Cumulative Convertible Preferred Stock (Series 2003). Incorporated herein by reference to Exhibit 3.1.2 to Registrant’s Form 8-K filed June 6, 2006.
4.	Registrant’s Certificate of Designation for 4.125% Cumulative Convertible Preferred Stock, as amended. Incorporated herein by reference to Exhibit 3.1.5 to Registrant’s Form 10-K for the year ended December 31, 2005. Certificate of Elimination for 4.125% Cumulative Convertible Preferred Stock. Incorporated herein by reference to Exhibit 3.1.1 to Registrant’s Form 8-K filed June 6, 2006.
5.	Registrant’s Certificate of Designation for 5.0% Cumulative Convertible Preferred Stock (Series 2005). Incorporated herein by reference to Exhibit 3.1.6 of the Registrant’s Form 10-Q for the quarter ended March 31, 2005.
6.	Registrant’s Certificate of Designation of 4.50% Cumulative Convertible Preferred Stock. Incorporated herein by reference to Exhibit 3.1 to Registrant’s current report on Form 8-K filed September 15, 2005.
7.	Registrant’s Certificate of Designation of 5.0% Cumulative Convertible Preferred Stock. Incorporated herein by reference to Exhibit 3.1 to Registrant’s current report on Form 8-K filed November 9, 2005.

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8.	Registrant’s Amended and Restated Bylaws. Incorporated herein by reference to Exhibit 3.2 to Registrant’s Form 10-K for the year ended December 31, 2003.
9.	Rights Agreement dated July 15, 1998 between Registrant and UMB Bank, N.A., as Rights Agent. Incorporated herein by reference to Exhibit 1 to Registrant’s registration statement on Form 8-A filed July 16, 1998. Amendment No. 1 to Rights Agreement dated September 11, 1998. Incorporated herein by reference to Exhibit 10.3 to the Registrant’s quarterly report on Form10-Q for the quarter ended September 30, 1998.
10.	Amendment No. 2 to Rights Agreement dated March 3, 2006.

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Pursuant to the requirements of Section 12 of the Securities Exchange Act of 1934, the registrant has duly caused this registration statement to be signed on its behalf by the undersigned, thereto duly authorized.

Registrant:

CHESAPEAKE ENERGY CORPORATION

/s/ MARTHA A. BURGER

Martha A. Burger

Treasurer and Senior Vice President -

Human Resources

Date: June 28, 2006

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EXHIBIT INDEX
Exhibit No.	Document Description
1.		Registrant’s Restated Certificate of Incorporation, as amended. Incorporated herein by reference to Exhibit 3.1.1 to Registrant’s Form 10-Q for the quarter ended March 31, 2005. Amendment to Registrant’s Restated Certificate of Incorporation dated June 14, 2006. Incorporated herein by reference to Exhibit 3.1.1 to Registrant’s Form 8-K dated June 15, 2006.
2.		Registrant’s Certificate of Designation for Series A Junior Participating Preferred Stock, as amended. Incorporated herein by reference to Exhibit 3.1.2 to the Registrant’s Form 10-Q for the quarter ended March 31, 2005. Third Amendment to the Certificate of Designation for Series A Junior Participating Preferred Stock. Incorporated herein by reference to Exhibit 3.1.2 to Registrant’s Form 8-K dated June 15, 2006.
3.		Registrant’s Certificate of Designation for 5.0% Cumulative Convertible Preferred Stock (Series 2003), as amended. Incorporated herein by reference Exhibit 3.1.4 to Registrant’s Form 10-K for the year ended December 31, 2005. Certificate of Elimination for 5.0% Cumulative Convertible Preferred Stock (Series 2003). Incorporated herein by reference to Exhibit 3.1.2 to Registrant’s Form 8-K filed June 6, 2006.
4.		Registrant’s Certificate of Designation for 4.125% Cumulative Convertible Preferred Stock, as amended. Incorporated herein by reference to Exhibit 3.1.5 to Registrant’s Form 10-K for the year ended December 31, 2005. Certificate of Elimination for 4.125% Cumulative Convertible Preferred Stock. Incorporated herein by reference to Exhibit 3.1.1 to Registrant’s Form 8-K filed June 6, 2006.
5.		Registrant’s Certificate of Designation for 5.0% Cumulative Convertible Preferred Stock (Series 2005). Incorporated herein by reference to Exhibit 3.1.6 of the Registrant’s Form 10-Q for the quarter ended March 31, 2005.
6.		Registrant’s Certificate of Designation of 4.50% Cumulative Convertible Preferred Stock. Incorporated herein by reference to Exhibit 3.1 to Registrant’s current report on Form 8-K filed September 15, 2005.
7.		Registrant’s Certificate of Designation of 5.0% Cumulative Convertible Preferred Stock. Incorporated herein by reference to Exhibit 3.1 to Registrant’s current report on Form 8-K filed November 9, 2005.

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8.	Registrant’s Amended and Restated Bylaws. Incorporated herein by reference to Exhibit 3.2 to Registrant’s Form 10-K for the year ended December 31, 2003.
9.	Rights Agreement dated July 15, 1998 between Registrant and UMB Bank, N.A., as Rights Agent. Incorporated herein by reference to Exhibit 1 to Registrant’s registration statement on Form 8-A filed July 16, 1998. Amendment No. 1 to Rights Agreement dated September 11, 1998. Incorporated herein by reference to Exhibit 10.3 to the Registrant’s quarterly report on Form10-Q for the quarter ended September 30, 1998.
10.	Amendment No. 2 to Rights Agreement dated March 3, 2006.

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EX-10

EXHIBIT 10

AMENDMENT NO. 2 TO RIGHTS AGREEMENT

BETWEEN

CHESAPEAKE ENERGY CORPORATION

AND

UMB BANK, N.A., AS RIGHTS AGENT

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THIS AMENDMENT NO. 2 TO RIGHTS AGREEMENT (this “Second Amendment”), dated as of March 3, 2006, is by and between Chesapeake Energy Corporation, an Oklahoma corporation (the “Company”), and UMB Bank, N.A., as Rights Agent (the “Rights Agent”).

RECITALS:

WHEREAS, the Company and the Rights Agent have heretofore entered into a Rights Agreement, dated as of July 15, 1998, as amended on September 11, 1998 (the Rights Agreement”); and

WHEREAS, the Company desires to amend the Rights Agreement to revise Section 1(p); and

WHEREAS, the Board of Directors of the Company has unanimously approved the amendment to the Rights Agreement effected hereby and in accordance with Section 27 of the Rights Agreement, this Second Amendment can be effected without the approval of any holders of the Rights.

NOW THEREFORE, in consideration of the premises and the mutual agreements herein set forth and in accordance with Section 27 of the Rights Agreement, the parties hereby agree as follows:

1.Section 1(p) of the Rights Agreement is hereby amended, effective as of the date set forth above, by revising such Section to read in its entirety as follows:

“Exempt Person” shall mean (i) the Company or any Subsidiary (as such term is hereinafter defined) of the Company or any employee benefit plan of the Company, (ii) Aubrey K. McClendon, his spouse, lineal descendants and ascendants, heirs, executors or other legal representatives and any trusts established for the benefit of the foregoing, or any other person or entity in which the foregoing persons or entities are at the time of determination the direct record and beneficial owners of all outstanding voting securities (each a “McClendon

Stockholder”), or (iii) any Person that is not a McClendon Stockholder but who or which is a Beneficial Owner of Common Stock Beneficially Owned by a McClendon Stockholder (a “Second Tier Stockholder”), but only if the shares of Common Stock otherwise Beneficially Owned by such Second Tier Stockholder (“Second Tier Holder Shares”) do not exceed the sum of (A) such holder’s Second Tier Holder Shares held on the date hereof and (B) 1% of the shares of Common Stock of the Company then outstanding.

2.Except to the extent amended by this Second Amendment, the Rights Agreement shall continue in full force and effect.

3.Capitalized terms used herein but not defined shall have the meanings assigned to such terms in the Rights Agreement.

IN WITNESS WHEREOF, the parties hereto have caused this Second Amendment to be duly executed, all as of the day and year first above written.

CHESAPEAKE ENERGY CORPORATION

/s/ AUBREY K. MCCLENDON

Aubrey K. McClendon

Chairman of the Board and

Chief Executive Officer

UMB BANK, N.A.

/s/ MARK B. FLANNAGAN

Mark B. Flannagan

Vice President

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