CWEI Clayton Williams Energy, Inc.

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(1) Formerly reported as “Clajon Holdings, Inc.”

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INTRODUCTION

The following is an amendment (this “Amendment”) to that certain Schedule 13D filed by certain of the reporting persons filing this statement, being Clayton W. Williams, Jr. (“Mr. Williams”), Clajon Holdings Corporation (formerly reporting as Clajon Holdings, Inc.), CWPLCO, Inc., CW Stock Holdco GP, LLC and CW Stock Holdco, L.P. or their predecessors as follows:

(as amended, the “Original 13D”), to reflect changes in beneficial ownership of shares of Common Stock, $0.10 par value, of Clayton Williams Energy, Inc., a Delaware corporation (the “Issuer” or “CWEI”), by the Reporting Persons.

Item 1.                    Security and Issuer

This Schedule 13D relates to the common stock, $0.10 par value per share (the “CWEI Common Shares”) of the Issuer.  The address of the principal executive offices of the Issuer is 6 Desta Drive, Suite 6500, Midland, Texas 79705-5510.  Only those items of Schedule 13D, or portions thereof, being amended are included in this Amendment.  Except as expressly amended and modified by this Amendment, the Original 13D remains unchanged and in full force and effect.

Item 4.                    Purpose of Transaction

Item 4 of the Original 13D is hereby amended to add the following:

The information set forth under “Non-Dissent Agreement” in Item 6 below is incorporated by reference in its entirety into this Item 4.

Item 6.                    Contracts, Arrangements, Understandings or Relationships with Respect to Securities of the Issuer

Item 6 of the Original 13D is hereby amended to add the following:

Non-Dissent Agreement

On January 13, 2017, Noble Energy, Inc. (“Noble Energy”), Wild West Merger Sub, Inc., a Delaware corporation and indirect wholly owned subsidiary of Noble Energy (“Merger Sub”), NBL Permian LLC, a Delaware limited liability company and indirect wholly owned subsidiary of Noble Energy (“Merger Sub II”), and the Issuer, entered into an Agreement and Plan of Merger (the “Merger Agreement”) pursuant to which Noble Energy will acquire the Issuer in exchange for a combination of shares of common stock, par value $0.01 per share, of Noble Energy and cash.  Upon the terms and subject to the conditions of the Merger Agreement, (i) Merger Sub will merge with and into the Issuer (the “Merger”), with the Issuer continuing as the surviving corporation in the Merger and an indirect wholly owned subsidiary of Noble Energy, and (ii) thereafter, the Issuer will merge with and into Merger Sub II, with Merger Sub II continuing as the surviving company and an indirect wholly owned subsidiary of Noble Energy.

Contemporaneously with the execution of the Merger Agreement, Noble Energy and the Issuer (solely for certain specified purposes) entered into  an Agreement Not To Dissent (the “CW Non-Dissent Agreement”), dated January 13, 2017, with Mr. Williams, pursuant to which Mr. Williams agreed, among other things, not to exercise or assert any appraisal rights under Section 262 of the DGCL in connection with the Merger. Mr. Williams also has agreed, among other things, during the period from January 13, 2017 to and including the date of termination of the Merger Agreement, if any (the “Applicable Period”), (a) not to transfer any CWEI Common Shares held by the reporting persons as of January 13, 2017, and (b) to vote all of such CWEI Common Shares against any alternative proposals and against any amendment of the Issuer’s certificate of incorporation or by-laws or other proposal or transaction

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involving the Issuer or any of its subsidiaries, which amendment or other proposal or transaction would in any manner delay, impede, frustrate, prevent or nullify the Merger, the Merger Agreement or any of the transactions contemplated by the Merger Agreement or change in any manner the voting rights of any outstanding class of capital stock of the Issuer.  If the Merger Agreement is terminated by the Noble Energy in certain circumstances, including if the Issuer stockholders do not adopt the Merger Agreement, then the term of the Applicable Period under the CW Non-Dissent Agreement will be extended for an additional 180 days following the termination of the Merger Agreement.

The foregoing description of the CW Non-Dissent Agreement is qualified in its entirety by reference to such agreement, a copy of which is filed as Exhibit 7.16 hereto, and incorporated herein by reference.

Item 7.                    Material to Be Filed as Exhibits

Item 7 of the Original 13D is hereby amended to add the following:

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Signature

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.

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