Schedule 13G Amendment No. 4

Check the appropriate box to designate the rule pursuant to which this Schedule is filed:


(a)	¨	Broker or dealer registered under section 15 of the Act (15 U.S.C. 78o).

(b)	¨	Bank as defined in section 3(a)(6) of the Act (15 U.S.C. 78c).

(c)	¨	Insurance company as defined in section 3(a)(19) of the Act (15 U.S.C. 78c).

(d)	¨	Investment company registered under section 8 of the Investment Company Act of 1940 (15 U.S.C. 80a-8).

(e)	¨	An investment adviser in accordance with § 240.13d-1(b)(1)(ii)(E);

(f)	¨	An employee benefit plan or endowment fund in accordance with § 240.13d-1(b)(1)(ii)(F);

(g)	¨	A parent holding company or control person in accordance with § 240.13d-1(b)(1)(ii)(G);

(h)	¨	A savings association as defined in Section 3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813);

(i)	¨	A church plan that is excluded from the definition of an investment company under section 3(c)(14) of the Investment Company Act of 1940 (15 U.S.C. 80a-3);

(j)	¨	A non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J);

(k)	¨	Group, in accordance with § 240.13d-1(b)(1)(ii)(K).

Provide the following information regarding the aggregate number and percentage of the class of securities of the issuer identified in Item 1.

If this statement is being filed to report the fact that as of the date hereof the reporting person has ceased to be the beneficial owner of more than 5 percent of the class of securities, check the following: [X] (with respect to Mr. Hamm only).

The shares beneficially owned by Mr. Mackie are held by him as the co-trustee of two separate trusts for the benefit of children of Harold G. Hamm, the Chairman and Chief Executive Officer of the issuer, and the beneficiaries of these trusts have the right to receive dividends paid on, and proceeds from sale of, the shares beneficially owned. None of the individual beneficiaries of either trust has a right to dividends or proceeds representing more than 5% of the issuer’s shares outstanding.

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

The undersigned hereby agree that Amendment No. 4 to Schedule 13G, filed pursuant to the Securities Exchange Act of 1934 and executed by each of the undersigned of even date herewith, is filed on behalf of each of the undersigned.


(1)	Names of reporting persons: Bert H. Mackie
(2)	Check the appropriate box if a member of a group (see instructions) (a) ¨ (b) ¨
(3)	SEC use only
(4)	Citizenship or place of organization: United States
Number of shares beneficially owned by each reporting person with		(5)	Sole voting power 0
		(6)	Shared voting power 14,687,501
		(7)	Sole dispositive power 0
		(8)	Shared dispositive power 14,687,501
(9)	Aggregate amount beneficially owned by each reporting person 14,687,501
(10)	Check if the aggregate amount in Row (9) excludes certain shares (see instructions) ¨
(11)	Percent of class represented by amount in Row (9): 8.1%
(12)	Type of reporting person (see instructions): IN


1.	Names of reporting persons: H. Thomas Hamm
2.	Check the appropriate box if a member of a group (see instructions) (a) ¨ (b) ¨
3.	SEC use only
4.	Citizenship or place of organization: United States
Number of shares beneficially owned by each reporting person with		5.	Sole voting power 0
		6.	Shared voting power 8,800,087
		7.	Sole dispositive power 0
		8.	Shared dispositive power 8,800,087
9.	Aggregate amount beneficially owned by each reporting person 8,800,087
10.	Check if the aggregate amount in Row (9) excludes certain shares (see instructions) [ ]
11.	Percent of class represented by amount in Row (9): 4.9%
12.	Type of reporting person (see instructions): IN


(a)	Amount beneficially owned: 14,687,501

(b)	Percent of class: 8.1%

(c)	Number of shares as to which such person has:

(i)	Sole power to vote or to direct the vote:	0

(ii)	Shared power to vote or to direct the vote:	14,687,501

(iii)	Sole power to dispose or to direct the disposition of:	0

(iv)	Shares power to dispose or to direct the disposition of:	14,687,501



(a)	Amount beneficially owned: 8,800,087

(b)	Percent of class: 4.9%

(c)	Number of shares as to which such person has:

(i)	Sole power to vote or to direct the vote:	0

(ii)	Shared power to vote or to direct the vote:	8,800,087

(iii)	Sole power to dispose or to direct the disposition of:	0

(iv)	Shares power to dispose or to direct the disposition of:	8,800,087



Item 8.		Identification and Classification of Members of the Group.

		Not applicable.

Item 9.		Notice of Dissolution of Group.

		Not applicable.

Item 10.		Certifications.

		Not applicable.


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