XEC / Cimarex Energy Co. - Pengajuan SECLaporan Tahunan, Pernyataan Proksi

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 15 CERTIFICATION AND NOTICE OF TERMINATION OF REGISTRATION UNDER SECTION 12(g) OF THE SECURITIES EXCHANGE ACT OF 1934 OR SUSPENSION OF DUTY TO FILE REPORTS UNDER SECTIONS 13

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 15 CERTIFICATION AND NOTICE OF TERMINATION OF REGISTRATION UNDER SECTION 12(g) OF THE SECURITIES EXCHANGE ACT OF 1934 OR SUSPENSION OF DUTY TO FILE REPORTS UNDER SECTIONS 13 AND 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Commission File Number: 001-31446 CIMAREX ENERGY CO. (Exact name of registrant as specified in its c

XEC / Cimarex Energy Co / ADAGE CAPITAL PARTNERS GP, L.L.C. - CIMAREX ENERGY CO. Activist Investment

SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13D/A Under the Securities Exchange Act of 1934 (Amendment No. 2)* Cimarex Energy Co. (Name of Issuer) Common Stock, par value $0.01 per share (Title of Class of Securities) 171798101 (CUSIP Number) Robert Atchinson Adage Capital Partners GP, L.L.C. 200 Clarendon Street, 52nd Floor Boston, MA 02116 (617) 867-2800 (Name, Address and

As filed with the Securities and Exchange Commission on October 8, 2021

As filed with the Securities and Exchange Commission on October 8, 2021 Registration No.

As filed with the Securities and Exchange Commission on October 8, 2021

As filed with the Securities and Exchange Commission on October 8, 2021 Registration No.

As filed with the Securities and Exchange Commission on October 8, 2021

As filed with the Securities and Exchange Commission on October 8, 2021 Registration No.

As filed with the Securities and Exchange Commission on October 8, 2021

As filed with the Securities and Exchange Commission on October 8, 2021 Registration No.

As filed with the Securities and Exchange Commission on October 8, 2021

As filed with the Securities and Exchange Commission on October 8, 2021 Registration No.

As filed with the Securities and Exchange Commission on October 8, 2021

As filed with the Securities and Exchange Commission on October 8, 2021 Registration No.

As filed with the Securities and Exchange Commission on October 8, 2021

As filed with the Securities and Exchange Commission on October 8, 2021 Registration No.

Entry into a Material Definitive Agreement, Material Modification to Rights of Security Holders, Financial Statements and Exhibits

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): October 7, 2021 CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporation) (Commission File

Second Supplemental Indenture, dated September 21, 2021, between Cimarex Energy Co., as issuer, and U.S. Bank National Association, as trustee.

Exhibit No. 10.1 EXECUTION VERSION SECOND SUPPLEMENTAL INDENTURE Second Supplemental Indenture (this ?Supplemental Indenture?), dated as of September 21, 2021, between Cimarex Energy Co., a Delaware Corporation (the ?Company?), and U.S. Bank National Association, a national banking association, as trustee under the Indenture referred to below (the ?Trustee?). W I T N E S S E T H WHEREAS, the Compa

Third Supplemental Indenture, dated September 21, 2021, between Cimarex Energy Co., as issuer, and U.S. Bank National Association, as trustee.

Exhibit No. 10.2 EXECUTION VERSION THIRD SUPPLEMENTAL INDENTURE Third Supplemental Indenture (this ?Supplemental Indenture?), dated as of September 21, 2021, between Cimarex Energy Co., a Delaware Corporation (the ?Company?), and U.S. Bank National Association, a national banking association, as trustee under the Indenture referred to below (the ?Trustee?). W I T N E S S E T H WHEREAS, the Company

Amended and Restated Certificate of Incorporation of Cimarex Energy Co.

Exhibit 3.2 AMENDED AND RESTATED CERTIFICATE OF INCORPORATION OF CIMAREX ENERGY CO. October 1, 2021 FIRST. The name of the corporation is Cimarex Energy Co. (the ?Corporation?). SECOND. The address of the corporation?s registered office in the State of Delaware is Corporation Trust Center, 1209 Orange Street, Wilmington, New Castle County, Delaware 19801. The name of its registered agent at such a

Amendments to Articles of Incorporation or Bylaws; Change in Fiscal Year, Termination of a Material Definitive Agreement, Notice of Delisting or Failure to Satisfy a Continued Listing Rule or Standard; Transfer of Listing, Financial Statements and Exhibits, Completion of Acquisition or Disposition of Assets

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): October 1, 2021 CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporation) (Commission File

EX-99.25

NOTIFICATION OF THE REMOVAL FROM LISTING AND REGISTRATION OF THE STATED SECURITIES The New York Stock Exchange hereby notifies the SEC of its intention to remove the entire class of the stated securities from listing and registration on the Exchange at the opening of business on October 12, 2021, pursuant to the provisions of Rule 12d2-2 (a).

Amendment to Certificate of Designations to 8 1⁄8% Series A Cumulative Perpetual Convertible Preferred Stock of Cimarex Energy Co. (incorporated herein by reference to Exhibit 3.4 of Cimarex’s Current Report on Form 8-K filed with the SEC on October 1, 2021).

Exhibit 3.4 CIMAREX ENERGY CO. CERTIFICATE OF AMENDMENT TO CERTIFICATE OF DESIGNATIONS OF 8 1?8% SERIES A CUMULATIVE PERPETUAL CONVERTIBLE PREFERRED STOCK Cimarex Energy Co. (the ?Corporation?), a corporation organized and existing under the General Corporation Law of the State of Delaware (the ?DGCL?), hereby certifies that: FIRST: The Corporation desires to amend its Certificate of Designations

Certificate of Amendment to Certificate of Designations of 8 1∕8% Series A Cumulative Perpetual Convertible Preferred Stock, dated as of September 30, 2021

Exhibit 3.1 CIMAREX ENERGY CO. CERTIFICATE OF AMENDMENT TO CERTIFICATE OF DESIGNATIONS OF 8 1?8% SERIES A CUMULATIVE PERPETUAL CONVERTIBLE PREFERRED STOCK Cimarex Energy Co. (the ?Corporation?), a corporation organized and existing under the General Corporation Law of the State of Delaware (the ?DGCL?), hereby certifies that: FIRST: The Corporation?s Certificate of Designations of 8 1?8% Series A

Amended and Restated Bylaws of Cimarex Energy Co.

Exhibit 3.3 AMENDED AND RESTATED BYLAWS OF CIMAREX ENERGY CO. Adopted as of October 1, 2021 PREAMBLE These Bylaws contain provisions for the regulation and management of the affairs of Cimarex Energy Co., a Delaware corporation (the ?Corporation?). They are based in part upon provisions of the General Corporation Law of the State of Delaware (the ?DGCL?) and the Certificate of Incorporation of the

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): September 29, 2021 CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporation) (Commission F

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Filed by Cimarex Energy Co. pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-12 under the Securities Exchange Act of 1934 Subject Company: Cimarex Energy Co. Commission File No. for Registration Statement on Form S-4 filed by Cabot Oil & Gas Corporation: 333-257534 Date: September 22, 2021 The following communication is being filed in connection with the

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Filed by: Cabot Oil & Gas Corporation Pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-12 under the Securities Exchange Act of 1934 Subject Company: Cimarex Energy Co.

Other Events

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): September 21, 2021 CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporation) (Commission F

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): September 21, 2021 CIMAREX ENERGY

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): September 21, 2021 CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporation) (Commission F

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (date of earliest event reported): September 17, 2021 (September 16,

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (date of earliest event reported): September 17, 2021 (September 16, 2021) CABOT OIL & GAS CORPORATION (Exact name of registrant as specified in its charter) Delaware 1-10447 04-3072771 (State or other jurisdiction of

Second Amendment to Second Amended and Restated Credit Agreement, dated as of September 16, 2021, by and among Cabot Oil & Gas Corporation, the Lenders party thereto and JPMorgan Chase Bank, N.A., as Administrative Agent

Exhibit 10.1 Execution Version SECOND AMENDMENT TO SECOND AMENDED AND RESTATED CREDIT AGREEMENT dated as of September 16, 2021 among CABOT OIL & GAS CORPORATION, as Borrower, the Lenders party hereto and JPMORGAN CHASE BANK, N.A., as Administrative Agent SECOND AMENDMENT TO SECOND AMENDED AND RESTATED CREDIT AGREEMENT THIS SECOND AMENDMENT TO SECOND AMENDED AND RESTATED CREDIT AGREEMENT (this ?Ame

You can vote your shares by telephone, or via the Internet. Please follow the easy instructions on the enclosed proxy card. If you have any questions, or need assistance in voting your shares, please call our proxy solicitor: INNISFREE M&A INCORPORAT

Filed by Cimarex Energy Co. pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-12 under the Securities Exchange Act of 1934 Subject Company: Cimarex Energy Co. Commission File No. for Registration Statement on Form S-4 filed by Cabot Oil & Gas Corporation: 333-257534 Date: September 16, 2021 The following communication is being filed in connection with the

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Filed by Cimarex Energy Co. pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-12 under the Securities Exchange Act of 1934 Subject Company: Cimarex Energy Co. Commission File No. for Registration Statement on Form S-4 filed by Cabot Oil & Gas Corporation: 333-257534 Date: September 9, 2021 The following communications are being filed in connection with the

Regulation FD Disclosure, Financial Statements and Exhibits

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): September 8, 2021 CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporation) (Commission Fi

Exchange Consideration(1)

Exhibit 99.1 Cabot Oil & Gas Commences Private Exchange Offers and Cimarex Energy Commences Consent Solicitations HOUSTON, Sept. 8, 2021, Cabot Oil & Gas Corporation (NYSE: COG) (?Cabot?) and Cimarex Energy Co. (NYSE: XEC) (?Cimarex?) today announced that, in connection with the anticipated merger of Cimarex and a wholly owned subsidiary of Cabot, Cabot has commenced offers to eligible holders (as

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (date of earliest event reported): September 8, 2021 CABOT OIL & GAS

425 1 tm2127139d2425.htm 425 UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (date of earliest event reported): September 8, 2021 CABOT OIL & GAS CORPORATION (Exact name of registrant as specified in its charter) Delaware 1-10447 04-3072771 (State or other jurisdict

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): September 8, 2021 CIMAREX ENERGY

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): September 8, 2021 CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporation) (Commission Fi

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No.          )

TABLE OF CONTENTS UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 ? SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No.????????? ) ? Filed by the Registrant ? Filed by a Party other than the Registrant ? Check the appropriate box: ? Preliminary Proxy Statement ? ? Confidential, for Use of the Commission Only (as permi

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q (Mark One) ? Quarterly Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the Quarterly Period ended June 30, 2021 or ? Transition Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the transition period from to Commission File No. 001-31

dated and effective as of June 29, 2021,

EXECUTION VERSION AMENDMENT NO. 1 TO AGREEMENT AND PLAN OF MERGER This Amendment No. 1 to the Agreement and Plan of Merger (this ?Amendment?), dated and effective as of June 29, 2021, by and among Cabot Oil & Gas Corporation, a Delaware corporation (?Labrador?), Double C Merger Sub, Inc., a Delaware corporation and a wholly owned subsidiary of Labrador (?Merger Sub?), and Cimarex Energy Co., a Del

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Filed by Cimarex Energy Co. pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-12 under the Securities Exchange Act of 1934 Subject Company: Cimarex Energy Co. Commission File No. for Registration Statement on Form S-4 filed by Cabot Oil & Gas Corporation: 333-257534 Date: August 5, 2021 The following communication is being filed in connection with the prop

Regulation FD Disclosure, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): August 5, 2021 CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporation) (Commission File

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): August 5, 2021 CIMAREX ENERGY CO.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): August 5, 2021 CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporation) (Commission File

Operational Activity

Exhibit 99.1 News Release Cimarex Energy Co. Reports Second-Quarter 2021 Results Cimarex Energy Co. (NYSE: XEC) today reported second-quarter 2021 financial and operating results. Net income for second-quarter 2021 totaled $113.4 million, or $1.10 per share. Net income for the quarter was impacted by a mark-to-market loss on the Company's commodity derivative positions of $125.7 million. Excluding

Cabot Oil & Gas Corporation Reports Second Quarter 2021 Results

Exhibit 99.1 July 30, 2021 FOR MORE INFORMATION CONTACT Matt Kerin (281) 589-4642 Cabot Oil & Gas Corporation Reports Second Quarter 2021 Results HOUSTON, Jul. 30, 2021 /PRNewswire/ - Cabot Oil & Gas Corporation (NYSE: COG) (?Cabot? or the ?Company?) today reported financial and operating results for the second quarter of 2021. Second Quarter 2021 Highlights ?Net income of $30.5 million (or $0.08

Filed by: Cabot Oil & Gas Corporation

425 1 tm2123672d4425.htm 425 Filed by: Cabot Oil & Gas Corporation Pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-12 under the Securities Exchange Act of 1934 Subject Company: Cimarex Energy Co. Commission File No. for Registration Statement on Form S-4 filed by Cabot Oil & Gas Corporation: 333-257534 The following are excerpts from the transcript of Ca

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Filed by: Cabot Oil & Gas Corporation Pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-12 under the Securities Exchange Act of 1934 Subject Company: Cimarex Energy Co.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (date of earliest event reported): July 30, 2021 CABOT OIL & GAS COR

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (date of earliest event reported): July 30, 2021 CABOT OIL & GAS CORPORATION (Exact name of registrant as specified in its charter) Delaware 1-10447 04-3072771 (State or other jurisdiction of incorporation) (Commission

Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): July 22, 2021 CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporation) (Commission File N

Filed by: Cabot Oil & Gas Corporation

Filed by: Cabot Oil & Gas Corporation Pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-12 under the Securities Exchange Act of 1934 Subject Company: Cimarex Energy Co.

Filed by Cimarex Energy Co.

Filed by Cimarex Energy Co. pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-12 under the Securities Exchange Act of 1934 Subject Company: Cimarex Energy Co. Commission File No. for Registration Statement on Form S-4 filed by Cabot Oil & Gas Corporation: 333-257534 As previously disclosed, on June 14, 2021, notification and report forms under the Hart-Sco

XEC / Cimarex Energy Co / ADAGE CAPITAL PARTNERS GP, L.L.C. - CIMAREX ENERGY CO. Activist Investment

SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13D/A Under the Securities Exchange Act of 1934 (Amendment No. 1)* Cimarex Energy Co. (Name of Issuer) Common Stock, par value $0.01 per share (Title of Class of Securities) 171798101 (CUSIP Number) Robert Atchinson Adage Capital Partners GP, L.L.C. 200 Clarendon Street, 52nd Floor Boston, MA 02116 (617) 867-2800 (Name, Address and

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): June 29, 2021 CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporation) (Commission File N

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): June 29, 2021 CIMAREX ENERGY CO.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): June 29, 2021 CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporation) (Commission File N

(filed as Exhibit 10.1 to the Current Report on Registrant’s Form 8-K filed on June 30, 2021 (Co

Exhibit 10.1 June 29, 2021 Mr. Thomas E. Jorden [Address] Re: Treatment of your Golden Equity Awards Dear Tom: Reference is made to the Agreement and Plan of Merger (the ?Merger Agreement?), dated as of May 23, 2021, among Cabot Oil & Gas Corporation (?Cabot?), Double C Merger Sub, Inc., a wholly owned subsidiary of Cabot (?Merger Sub?), and Cimarex Energy Co. (?Cimarex?), pursuant to which Merger

Investor Presentation Combination of Cimarex & Cabot Oil & Gas June 2021 Combination of Cimarex and Cabot Oil & Gas 2 Creates a premier energy company delivering leading returns on and of capital Committed to delivering best-in-class capital returns

Filed by Cimarex Energy Co. pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-12 under the Securities Exchange Act of 1934 Subject Company: Cimarex Energy Co. Commission File No. for Registration Statement on Form S-4 filed by Cabot Oil & Gas Corporation: 333-257534 The following communication is being filed in connection with the proposed merger of Cimare

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D C 20549 Form 11-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D C 20549 Form 11-K x ANNUAL REPORT PURSUANT TO SECTION 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2020 OR ? TRANSITION REPORT PURSUANT TO SECTION 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission file number 001-31446 A.

Filed by Cimarex Energy Co.

Filed by Cimarex Energy Co. pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-12 under the Securities Exchange Act of 1934 Subject Company: Cimarex Energy Co. Commission File No.: 001-31446 Date: June 23, 2021 The following communication is being filed in connection with the proposed merger of Cimarex Energy Co. (?Cimarex?) and Cabot Oil & Gas Corporation

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (date of earliest event reported): June 17, 2021 CABOT OIL & GAS COR

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (date of earliest event reported): June 17, 2021 CABOT OIL & GAS CORPORATION (Exact name of registrant as specified in its charter) Delaware 1-10447 04-3072771 (State or other jurisdiction of incorporation) (Commission

Cimarex Energy Co.

SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13D Under the Securities Exchange Act of 1934 (Amendment No. )* Cimarex Energy Co. (Name of Issuer) Common Stock, par value $0.01 per share (Title of Class of Securities) 171798101 (CUSIP Number) Robert Atchinson Adage Capital Partners GP, L.L.C. 200 Clarendon Street, 52nd Floor Boston, MA 02116 (617) 867-2800 (Name, Address and Te

Filed by Cimarex Energy Co.

Filed by Cimarex Energy Co. pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-12 under the Securities Exchange Act of 1934 Subject Company: Cimarex Energy Co. Commission File No.: 001-31446 Date: June 11, 2021 The following communication is being filed in connection with the proposed merger of Cimarex Energy Co. (?Cimarex?) and Cabot Oil & Gas Corporation

Filed by Cimarex Energy Co.

Filed by Cimarex Energy Co. pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-12 under the Securities Exchange Act of 1934 Subject Company: Cimarex Energy Co. Commission File No.: 001-31446 Date: June 4, 2021 The following communication is being filed in connection with the proposed merger of Cimarex Energy Co. (Cimarex) and Cabot Oil & Gas Corporation (Ca

Filed by Cimarex Energy Co.

425 1 tm2117341d7425.htm 425 Filed by Cimarex Energy Co. pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-12 under the Securities Exchange Act of 1934 Subject Company: Cimarex Energy Co. Commission File No.: 001-31446 Date: June 2, 2021 The following communication is being filed in connection with the proposed merger of Cimarex Energy Co. (“Cimarex”) and

Filed by: Cabot Oil & Gas Corporation

Filed by: Cabot Oil & Gas Corporation Pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14d-2(b) and Rule 14a-12 under the Securities Exchange Act of 1934 Subject Company: Cimarex Energy Co.

Filed by Cimarex Energy Co.

Filed by Cimarex Energy Co. pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-12 under the Securities Exchange Act of 1934 Subject Company: Cimarex Energy Co. Commission File No.: 001-31446 Date: May 26, 2021 The following communication is being filed in connection with the proposed merger of Cimarex Energy Co. (?Cimarex?) and Cabot Oil & Gas Corporation (

Filed by Cimarex Energy Co.

Filed by Cimarex Energy Co. pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-12 under the Securities Exchange Act of 1934 Subject Company: Cimarex Energy Co. Commission File No.: 001-31446 Date: May 25, 2021 The following communication is being filed in connection with the proposed merger of Cimarex Energy Co. (?Cimarex?) and Cabot Oil & Gas Corporation (

Filed by Cimarex Energy Co.

Filed by Cimarex Energy Co. pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-12 under the Securities Exchange Act of 1934 Subject Company: Cimarex Energy Co. Commission File No.: 001-31446 Date: May 25, 2021 The following communication is being filed in connection with the proposed merger of Cimarex Energy Co. (?Cimarex?) and Cabot Oil & Gas Corporation (

Entry into a Material Definitive Agreement, Financial Statements and Exhibits, Other Events

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): May 23, 2021 CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporation) (Commission File Nu

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Filed by Cimarex Energy Co. pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-12 under the Securities Exchange Act of 1934 Subject Company: Cimarex Energy Co. Commission File No.: 001-31446 Date: May 24, 2021 The following communications are being filed in connection with the proposed merger of Cimarex Energy Co. (?Cimarex?) and Cabot Oil & Gas Corporation

Filed by: Cabot Oil & Gas

Filed by: Cabot Oil & Gas pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14d-2(b) and Rule 14a-12 under the Securities Exchange Act of 1934 Subject Company: Cimarex Energy Commission File Number: 001-31446 ? Hi everyone.

Creating a Premier, Free Cash Flow Focused Energy Company May 24, 2021 MERGER OF EQUALS

Exhibit 99.2 Creating a Premier, Free Cash Flow Focused Energy Company May 24, 2021 MERGER OF EQUALS Disclaimers 2 Cautionary Statement Regarding Forward - Looking Information This presentation contains certain ?forward - looking statements? within the meaning of federal securities laws. Words such as ?an ticipates,? ?believes,? ?expects,? ?intends,? ?plans,? ?outlook,? ?will,? ?should,? ?may? and

Cabot Oil & Gas and Cimarex Energy to Combine in All-Stock Merger of Equals

Exhibit 99.1 Cabot Oil & Gas and Cimarex Energy to Combine in All-Stock Merger of Equals Creating a Premier, Diversified Energy Company with a Strong Free Cash Flow Profile; Positioned to Deliver Superior and Sustainable Returns HOUSTON and DENVER, May 24, 2021 ? Cabot Oil & Gas Corporation (?Cabot?) (NYSE: COG) and Cimarex Energy Co. (?Cimarex?) (NYSE: XEC) today announced that they have entered

Three Memorial City Plaza 840 Gessner Road, Suite 1400, Houston, Texas 77024-4152 • P.O. Box 4544, Houston, Texas 77210-4544 • 281 589-4600 An Equal Opportunity Employer

Filed by: Cabot Oil & Gas Corporation Pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14d-2(b) and Rule 14a-12 under the Securities Exchange Act of 1934 Subject Company: Cimarex Energy Co.

Filed by: Cabot Oil & Gas Corporation

Filed by: Cabot Oil & Gas Corporation Pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14d-2(b) and Rule 14a-12 under the Securities Exchange Act of 1934 Subject Company: Cimarex Energy Co.

Three Memorial City Plaza 840 Gessner Road, Suite 1400, Houston, Texas 77024-4152 • P.O. Box 4544, Houston, Texas 77210-4544 • 281 589-4600 An Equal Opportunity Employer

Filed by: Cabot Oil & Gas Corporation Pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14d-2(b) and Rule 14a-12 under the Securities Exchange Act of 1934 Subject Company: Cimarex Energy Co.

Filed by: Cabot Oil & Gas Corporation

Filed by: Cabot Oil & Gas Corporation Pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14d-2(b) and Rule 14a-12 under the Securities Exchange Act of 1934 Subject Company: Cimarex Energy Co.

Filed by: Cabot Oil & Gas Corporation

Filed by: Cabot Oil & Gas Corporation Pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14d-2(b) and Rule 14a-12 under the Securities Exchange Act of 1934 Subject Company: Cimarex Energy Co.

Filed by: Cabot Oil & Gas Corporation

Filed by: Cabot Oil & Gas Corporation Pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14d-2(b) and Rule 14a-12 under the Securities Exchange Act of 1934 Subject Company: Cimarex Energy Co.

Filed by: Cabot Oil & Gas Corporation

Filed by: Cabot Oil & Gas Corporation Pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14d-2(b) and Rule 14a-12 under the Securities Exchange Act of 1934 Subject Company: Cimarex Energy Co.

Agreement and Plan of Merger, dated as of May 23, 2021, among Cabot Oil & Gas Corporation, Double C Merger Sub, Inc.

Exhibit 2.1 ? EXECUTION VERSION ? AGREEMENT AND PLAN OF MERGER ? among ? CABOT OIL?& GAS CORPORATION, ? DOUBLE C MERGER SUB,?INC. ? and ? CIMAREX ENERGY CO. ? Dated as of May?23, 2021 ? ? ? ? ? ? ? ? TABLE OF CONTENTS ? Page ? Article?I CERTAIN DEFINITIONS 2 ? ? ? 1.1 Certain Definitions 2 ? ? ? 1.2 Terms Defined Elsewhere 2 ? ? ? Article?II THE MERGER 4 ? ? ? 2.1 The Merger 4 ? ? ? 2.2 Closing 5

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): May 23, 2021 CIMAREX ENERGY CO. (

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): May 23, 2021 CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporation) (Commission File Nu

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (date of earliest event reported): May 23, 2021 CABOT OIL & GAS CORP

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (date of earliest event reported): May 23, 2021 CABOT OIL & GAS CORPORATION (Exact name of registrant as specified in its charter) Delaware 1-10447 04-3072771 (State or other jurisdiction of incorporation) (Commission

As filed with the United States Securities and Exchange Commission on May 20, 2021

As filed with the United States Securities and Exchange Commission on May 20, 2021 Registration No.

Cimarex Energy Co. Amended and Restated 2019 Equity Incentive Plan (incorporated by reference to Exhibit 99.1 to the Registration Statement on Form S-8 of Cimarex (Registration No. 333-256323)).

Exhibit 99.1 CIMAREX ENERGY CO. Amended and Restated 2019 EQUITY INCENTIVE PLAN Adopted by the Board on February 17, 2021 Approved by the Company?s stockholders on May 12, 2021 8,720,723 shares total, consisting of 6,900,000 plus 1,820,723 available On May 12, 2021 under 2019 Equity Incentive Plan 1. ESTABLISHMENT AND PURPOSE OF PLAN Cimarex Energy Co., a Delaware corporation (the ?Company?), here

Amended and Restated By-laws of Cimarex Energy Co. dated May 12, 2021.

Exhibit 3.2 AMENDED AND RESTATED BYLAWS OF CIMAREX ENERGY CO. (hereinafter called the ?Corporation?) (amended and restated May 12, 2021) Article I OFFICES Section 1. Registered Office. The registered office of the Corporation shall be in the City of Wilmington, County of New Castle, State of Delaware. Section 2. Other Offices. The Corporation may also have offices at such other places, both within

Material Modification to Rights of Security Holders

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 Or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): May 12, 2021 CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporation) (Commission File Nu

Amended and Restated Certificate of Incorporation of Cimarex Energy Co., dated May 12, 2021 (filed as Exhibit 3.1 to Cimarex’s Current Report on Form 8-K filed with the SEC on May 14, 2021)

Exhibit 3.1 AMENDED AND RESTATED CERTIFICATE OF INCORPORATION OF CIMAREX ENERGY CO. 1. The name of the Corporation is Cimarex Energy Co. 2. The name under which the Corporation was originally incorporated was Helmerich & Payne Exploration and Production Co. and the original Certificate of Incorporation of the Corporation was filed with the Secretary of State of the State of Delaware on February 14

Quarterly Report - 10-Q

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q (Mark One) ? Quarterly Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the Quarterly Period ended March 31, 2021 or ? Transition Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the transition period from to Commission File No. 001-3

Operational Activity

News Release Cimarex Energy Co. Reports First-Quarter 2021 Results Cimarex Energy Co. (NYSE: XEC) today reported first-quarter 2021 financial and operating results. Net income for first-quarter 2021 totaled $128.1 million, or $1.25 per share. Net income for the quarter was impacted by a mark-to-market loss on the Company's commodity derivative positions of $99.4 million. Excluding the impact of th

Regulation FD Disclosure, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): May 5, 2021 CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporation) (Commission File Num

Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): April 19, 2021 CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporation) (Commission File

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 Or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): April 14, 2021 CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporation) (Commission File

SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Schedule 13G Under the Securities Exchange Act of 1934 (Amendment No.: 8)*

SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Schedule 13G Under the Securities Exchange Act of 1934 (Amendment No.: 8)* Name of issuer: Cimarex Energy Co. Title of Class of Securities: Common Stock CUSIP Number: 171798101 Date of Event Which Requires Filing of this Statement: March 31, 2021 Check the appropriate box to designate the rule pursuant to which this Schedule is filed: ??Rul

- DEFA14A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. ) Filed by the Registrant x Filed by a Party other than the Registrant o Check the appropriate box: o Preliminary Proxy Statement o Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) o Defin

Amended and Restated By-laws of Cimarex, dated May 12, 2021 (filed as Appendix C to Cimarex’s Definitive Proxy Statement on Schedule 14A filed with the SEC on March 26, 2021).

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. ) Filed by the Registrant ? Filed by a Party other than the Registrant o ? ? ? ? ? ? ? ? ? Check the appropriate box: ? ? ? ? ? ? ? ? ? o Preliminary Proxy Statement ? ? ? ? ? ? ? ? ? o Confidential, f

Regulation FD Disclosure

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 Or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): March 17, 2021 CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporation) (Commission File

- PRE 14A

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. ) Filed by the Registrant ? Filed by a Party other than the Registrant o ? ? ? ? ? ? ? ? ? Check the appropriate box: ? ? ? ? ? ? ? ? ? ? Preliminary Proxy Statement ? ? ? ? ? ? ? ? ? o Confidential, f

Significant subsidiaries of the Registrant. *

Exhibit 21.1 List of Significant Subsidiaries Cimarex Energy Co. of Colorado, a Texas corporation Cimarex Gas Gathering, Inc., a Texas corporation Key Production Company, Inc., a Delaware corporation Magnum Hunter Production, Inc., a Texas corporation Oklahoma Gas Processing, Inc., a Delaware corporation Prize Energy Resources, Inc., a Delaware corporation Resolute Natural Resources Southwest, LLC

Form of Notice of Grant of Performance Stock Units and Award Agreement (Performance Award). + *

Cimarex Energy Co. 1700 Lincoln Street, Suite 3700 Denver, Colorado 80203-4553 NOTICE OF GRANT OF PERFORMANCE STOCK UNITS AND AWARD AGREEMENT (PERFORMANCE AWARD) Name: Participant ID: Plan: 2019 Equity Incentive Plan Date of Award: December 10, 2020 Number of shares of Restricted Stock: Restriction Period Ends: December 1, 2023 By accepting this agreement online, you and Cimarex Energy Co. (the ?C

Description of Registrant’s Securities *

Exhibit 4.15 DESCRIPTION OF THE REGISTRANT?S SECURITIES REGISTERED PURSUANT TO SECTION 12 OF THE SECURITIES EXCHANGE ACT OF 1934 DESCRIPTION OF CAPITAL STOCK The following descriptions of Cimarex's capital stock and provisions of its amended and restated certificate of incorporation and amended and restated bylaws are summaries and are qualified by reference to the complete text of the amended and

Annual Report - 10-K

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Form 10-K (Mark One) ? ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2020 OR ? TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission file number 001-314

from DeGolyer and MacNaughton, independent petroleum engineering consulting firm, reporting the results of its audit of Cimarex reserves as of December 31, 20

DeGolyer and MacNaughton 5001 Spring Valley Road Suite 800 East Dallas, Texas 75244 January 20, 2021 Cimarex Energy Company 1700 Lincoln Street Suite 3700 Denver, Colorado 80203 Ladies and Gentlemen: Pursuant to your request, this report of third party presents an independent evaluation, as of December 31, 2020, of the estimated net proved oil, condensate, natural gas liquids (NGL), and gas reserves of certain properties in which Cimarex Energy Company (Cimarex) has represented it holds an interest.

Power of Attorney of directors of the Registrant. *

Exhibit 24.1 POWER OF ATTORNEY KNOW ALL MEN BY THESE PRESENTS, that each person whose signature appears below hereby constitutes and appoints Thomas E. Jorden and G. Mark Burford and each of them acting alone, his true and lawful attorney-in-fact and agent, with full power of substitution and revocation, for him in any and all capacities, to execute and cause to be filed with the Securities and Ex

N E W S Cimarex Energy Co. 1700 Lincoln Street, Suite 3700 Denver, CO 80203 Phone: (303) 295-3995

N E W S Cimarex Energy Co. 1700 Lincoln Street, Suite 3700 Denver, CO 80203 Phone: (303) 295-3995 Cimarex Announces 2021 Capital Investment Plans and Production and Expense Guidance DENVER, February 22, 2021 - Cimarex Energy Co. (NYSE: XEC) today announced its projected 2021 total capital investment (including midstream capital) of $650 - 750 million. The table below shows a breakdown of the proje

N E W S Cimarex Energy Co. 1700 Lincoln Street, Suite 3700 Denver, CO 80203 Phone: (303) 295-3995

N E W S Cimarex Energy Co. 1700 Lincoln Street, Suite 3700 Denver, CO 80203 Phone: (303) 295-3995 Cimarex Reports Fourth Quarter and Full Year 2020 Results ?Fourth quarter oil production averaged 67.8 MBbls per day ?Full year oil production averaged 76.7 MBbls per day ?2020 total capital investment of $577.2 million; below guidance range ?Generated $904.2 million of net cash from operating activit

Regulation FD Disclosure, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): February 22, 2021 CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporation) (Commission Fi

SCHEDULE 13G

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. )* Cimarex Energy Co. (Name of Issuer) Common Stock (Title of Class of Securities) 171798101 (CUSIP Number) December 31, 2020 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to designate the rule pursuant to which this Sched

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 2)* CIMAREX ENERGY CO (Name of Issuer) Common Stock (Title of Class of Securities) 171798101 (CUSIP Number)

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 2)* CIMAREX ENERGY CO (Name of Issuer) Common Stock (Title of Class of Securities) 171798101 (CUSIP Number) December 31, 2020 (Date of Event which Requires Filing of this Statement) Check the appropriate box to designate the rule pursuant to which this Sched

SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Schedule 13G Under the Securities Exchange Act of 1934 (Amendment No.: 7)*

SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Schedule 13G Under the Securities Exchange Act of 1934 (Amendment No.: 7)* Name of issuer: Cimarex Energy Co. Title of Class of Securities: Common Stock CUSIP Number: 171798101 Date of Event Which Requires Filing of this Statement: December 31, 2020 Check the appropriate box to designate the rule pursuant to which this Schedule is filed: ☒ 

Regulation FD Disclosure

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 Or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): December 11, 2020 CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporation) (Commission Fi

Regulation FD Disclosure - FORM 8-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 Or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): November 6, 2020 CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporation) (Commission Fil

Quarterly Report - 10-Q

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q (Mark One) ☒ Quarterly Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the Quarterly Period ended September 30, 2020 or ☐ Transition Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the transition period from to Commission File No. 0

Regulation FD Disclosure, Results of Operations and Financial Condition - 8-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): November 4, 2020 CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporation) (Commission Fil

N E W S Cimarex Energy Co. 1700 Lincoln Street, Suite 3700 Denver, CO 80203 Phone: (303) 295-3995

N E W S Cimarex Energy Co. 1700 Lincoln Street, Suite 3700 Denver, CO 80203 Phone: (303) 295-3995 Cimarex Reports Third Quarter 2020 Results •Generated Net Cash Provided by Operating Activities of $259 million •Generated $139 million of free cash flow after dividend (Non-GAAP) •Invested $83 million in the quarter •Oil production averaged 71,600 barrels per day DENVER, November 4, 2020 - Cimarex En

Regulation FD Disclosure

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 Or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): September 3, 2020 CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporation) (Commission Fi

Quarterly Report - 10-Q

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q (Mark One) ☒ Quarterly Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the Quarterly Period ended June 30, 2020 or ☐ Transition Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the transition period from to Commission File No. 001-31

Regulation FD Disclosure, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): August 5, 2020 CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporation) (Commission File

N E W S Cimarex Energy Co. 1700 Lincoln Street, Suite 3700 Denver, CO 80203 Phone: (303) 295-3995

N E W S Cimarex Energy Co. 1700 Lincoln Street, Suite 3700 Denver, CO 80203 Phone: (303) 295-3995 Cimarex Reports Second Quarter 2020 Results •Generated Cash from Operating Activities of $145 million in the quarter •Invested $84 million in the second quarter •$26 million in free cash flow after dividend •Oil production averaged 78,000 barrels per day DENVER, August 5, 2020 - Cimarex Energy Co. (NY

Form 8-K/A filed July 2, 2020 (Commission File No. 001-31446) and incorporated herein by reference).

Exhibit 10.1 SUCCESSION AGREEMENT This SUCCESSION AGREEMENT (the “Agreement”) is made and entered into to be effective as of the 1st day of July 2020 (the “Effective Date”), by and between Cimarex Energy Co., a Delaware corporation (the “Company”), and Joseph R. Albi (“Executive”). WHEREAS, Executive is a founder of the Company and its Executive Vice President—Operations and Chief Operating Office

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K/A CURRENT REPORT Pursuant to Section 13 Or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): January 10, 2020 CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporation) (Commission F

- 11-K

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D C 20549 Form 11-K x ANNUAL REPORT PURSUANT TO SECTION 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2019 OR o TRANSITION REPORT PURSUANT TO SECTION 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission file number 001-31446 A.

First Amendment to Amended and Restated Credit Agreement, dated June 3, 2020, among the Company, as borrower, JPMorgan Chase Bank, N.A., as administrative agent, Wells Fargo Bank, N.A., as syndication agent, the co-documentation agents party thereto, J.P. Morgan Chase Bank, N.A. and Wells Fargo Securities, LLC, as lead arrangers and bookrunners, and the lenders party thereto.

Exhibit 10.1 Execution Version First Amendment to Amended and Restated Credit Agreement This First Amendment to Amended and Restated Credit Agreement (this “First Amendment”) dated as of June 3, 2020, is among Cimarex Energy Co., a Delaware corporation (the “Borrower”), the lenders party to the Credit Agreement referred to below (collectively, the “Lenders”) party hereto, and JPMorgan Chase Bank,

Entry into a Material Definitive Agreement, Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K/A CURRENT REPORT Pursuant to Section 13 Or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): June 3, 2020 (February 5, 2019) CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporation

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K/A (Amendment No. 1) CURRENT REPORT Pursuant to Section 13 Or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): March 9, 2020 CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporation

Compensation Agreement (filed as Exhibit 10.2 to the Current Report on Form 8-K/A filed May 12, 2020 (Commission File No. 001-31446) and incorporated herein by reference).

Exhibit 10.2 [Cimarex letterhead] [ ], 2020 [Executive] [address] RE: Severance Compensation Agreement, by and between Cimarex Energy Co. (the “Company”) and [ ] (the “Executive”) dated as of [ ], 2020 (the “Agreement”) Dear [ ], Pursuant to Section 8.10 of the Agreement, this letter is to document the agreement of the Company and the Executive that, for purposes of the Agreement and notwithstandi

Quarterly Report - 10-Q

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q (Mark One) ☒ Quarterly Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the Quarterly Period ended March 31, 2020 or ☐ Transition Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the transition period from to Commission File No. 001-3

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 Or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): May 6, 2020 CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporation) (Commission File Num

Regulation FD Disclosure, Material Impairments, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): May 6, 2020 CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporation) (Commission File Num

N E W S Cimarex Energy Co. 1700 Lincoln Street, Suite 3700 Denver, CO 80203 Phone: (303) 295-3995

N E W S Cimarex Energy Co. 1700 Lincoln Street, Suite 3700 Denver, CO 80203 Phone: (303) 295-3995 Cimarex Reports First Quarter 2020 Results; Issues Abridged Guidance • Q1 Oil production averaged 89.8 MBbls/d • Invested $274 million in the first quarter DENVER, May 6, 2020 - Cimarex Energy Co. (NYSE: XEC) today reported a first quarter 2020 net loss of $774.3 million, or $7.77 per share, compared

Cimarex Announces Further Reduction to 2020 Capital Plans; Curtails 30% of May Volumes

Exhibit 99.1 N E W S Cimarex Energy Co. 1700 Lincoln Street, Suite 3700 Denver, CO 80203 Phone: (303) 295-3995 Cimarex Announces Further Reduction to 2020 Capital Plans; Curtails 30% of May Volumes · Drilling Activity Reduced to One Rig · Completion Activity Deferred DENVER, April 15, 2020 - Cimarex Energy Co. (NYSE: XEC) today announced that, due to the continued weakness in oil prices, it now ex

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 Or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): April 15, 2020 CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporation) (Commission File

XEC / Cimarex Energy Co. DEFA14A - - DEFA14A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. ) Filed by the Registrant x Filed by a Party other than the Registrant o Check the appropriate box: o Preliminary Proxy Statement o Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) o Defin

XEC / Cimarex Energy Co. DEFA14A - - DEFA14A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. ) Filed by the Registrant x Filed by a Party other than the Registrant o Check the appropriate box: o Preliminary Proxy Statement o Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) o Defin

XEC / Cimarex Energy Co. DEF 14A - - DEF 14A

Use these links to rapidly review the document TABLE OF CONTENTS Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.

Form of Notice of Grant of Performance Stock Units and Award Agreement (Performance Award)

Exhibit 10.2 Cimarex energy co. 1700 Lincoln Street, Suite 3700 Denver, Colorado 80203-4553 NOTICE OF GRANT OF PERFORMANCE STOCK UNITS AND AWARD AGREEMENT (PERFORMANCE AWARD) Name: Participant ID: Plan: 2019 Equity Incentive Plan Date of Award: December 5, 2019 Number of shares of Restricted Stock: Restriction Period Ends: December 1, 2022 By accepting this agreement online, you and Cimarex Energy

Form of Severance Compensation Agreement of certain executive officers of Cimarex Energy Co. (incorporated herein by reference to Exhibit 10.1 of Cimarex’s Current Report on Form 8-K filed with the SEC on March 13, 2020).

Exhibit 10.1 SEVERANCE COMPENSATION AGREEMENT This Severance Compensation Agreement (this “Agreement”) is made and entered into as of [month/day/year] (the “Effective Date”) by and between [] (the “Executive”) and Cimarex Energy Co., a Delaware corporation (the “Company”). RECITALS WHEREAS, Executive is an officer of the Company. WHEREAS, the Company believes that appropriate steps should be taken

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 Or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): March 9, 2020 CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporation) (Commission File N

Power of Attorney of directors of the Registrant. *

Exhibit 24.1 POWER OF ATTORNEY KNOW ALL MEN BY THESE PRESENTS, that each person whose signature appears below hereby constitutes and appoints Thomas E. Jorden and G. Mark Burford and each of them acting alone, his true and lawful attorney-in-fact and agent, with full power of substitution and revocation, for him in any and all capacities, to execute and cause to be filed with the Securities and Ex

Annual Report - 10-K

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Form 10-K (Mark One) ☒ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2019 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission file number 001-314

Significant subsidiaries of the Registrant. *

Exhibit 21.1 List of Significant Subsidiaries Cimarex Energy Co. of Colorado, a Texas corporation Cimarex Gas Gathering, Inc., a Texas corporation Key Production Company, Inc., a Delaware corporation Magnum Hunter Production, Inc., a Texas corporation Oklahoma Gas Processing, Inc., a Delaware corporation Prize Energy Resources, Inc., a Delaware corporation Resolute Natural Resources Southwest, LLC

Description of Registrant’s Securities *

Exhibit 4.15 DESCRIPTION OF THE REGISTRANT’S SECURITIES REGISTERED PURSUANT TO SECTION 12 OF THE SECURITIES EXCHANGE ACT OF 1934 DESCRIPTION OF CAPITAL STOCK The following descriptions of Cimarex's capital stock and provisions of its amended and restated certificate of incorporation and amended and restated bylaws are summaries and are qualified by reference to the complete text of the amended and

Letter dated January 28, 2020 from DeGolyer and MacNaughton, independent petroleum engineering consulting firm, reporting the results of its audit of Cimarex reserves as of December 31, 2019 of certain selected properties. *

DeGolyer and MacNaughton 5001 Spring Valley Road Suite 800 East Dallas, Texas 75244 Exhibit 99.

Regulation FD Disclosure

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 Or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): February 25, 2020 CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporation) (Commission Fi

N E W S Cimarex Energy Co. 1700 Lincoln Street, Suite 3700 Denver, CO 80203 Phone: (303) 295-3995

N E W S Cimarex Energy Co. 1700 Lincoln Street, Suite 3700 Denver, CO 80203 Phone: (303) 295-3995 Cimarex Announces 2020 Capital Investment Plans and Production and Expense Guidance • Total capital investment estimated to be $1.25 - 1.35 billion – Includes drilling and completion capital of $0.95 - 1.05 billion • Generates nine percent oil growth at the midpoint • Free cash flow positive in 2020 a

N E W S Cimarex Energy Co. 1700 Lincoln Street, Suite 3700 Denver, CO 80203 Phone: (303) 295-3995

EX-99.1 2 a123119pressreleasexec.htm EXHIBIT 99.1 N E W S Cimarex Energy Co. 1700 Lincoln Street, Suite 3700 Denver, CO 80203 Phone: (303) 295-3995 Cimarex Reports Fourth Quarter and Full Year 2019 Results • Fourth quarter oil production averaged 92.0 MBbls per day ◦ Full year oil production averaged 86.2 MBbls per day • 2019 capital investment (including midstream) totaled $1.32 billion; below gu

Regulation FD Disclosure

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): February 19, 2020 CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporation) (Commission Fi

XEC / Cimarex Energy Co. / VANGUARD GROUP INC - SCHEDULE 13G/A Passive Investment

SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Schedule 13G Under the Securities Exchange Act of 1934 (Amendment No.: 6)* Name of issuer: Cimarex Energy Co Title of Class of Securities: Common Stock CUSIP Number: 171798101 Date of Event Which Requires Filing of this Statement: December 31, 2019 Check the appropriate box to designate the rule pursuant to which this Schedule is filed: ☒ R

XEC / Cimarex Energy Co. / Boston Partners - ROBECO INVESTMENT MANAGEMENT INC. Passive Investment

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 1)* CIMAREX ENERGY CO (Name of Issuer) Common Stock (Title of Class of Securities) 171798101 (CUSIP Number) December 31, 2019 (Date of Event which Requires Filing of this Statement) Check the appropriate box to designate the rule pursuant to which this Sched

Cimarex Announces Retirement of Joseph R. Albi, Executive Vice President, Chief Operating Officer and Director

Exhibit 99.1 Cimarex Energy Co. 1700 Lincoln Street, Suite 3700 Denver, CO 80203 Phone: (303) 295-3995 Cimarex Announces Retirement of Joseph R. Albi, Executive Vice President, Chief Operating Officer and Director DENVER, January 15, 2020 - Cimarex Energy Co. (NYSE: XEC) today announced that its Executive Vice President and Chief Operating Officer (COO), Joe Albi, has informed management and the C

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 Or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): January 10, 2020 CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporation) (Commission Fil

Regulation FD Disclosure

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 Or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): November 12, 2019 CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporation) (Commission Fi

Quarterly Report - 10-Q

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q (Mark One) ☒ Quarterly Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the Quarterly Period ended September 30, 2019 or ☐ Transition Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the transition period from to Commission File No. 0

N E W S Cimarex Energy Co. 1700 Lincoln Street, Suite 3700 Denver, CO 80203 Phone: (303) 295-3995

N E W S Cimarex Energy Co. 1700 Lincoln Street, Suite 3700 Denver, CO 80203 Phone: (303) 295-3995 Cimarex Reports Third Quarter 2019 Results • Oil production averaged 89.7 MBbls/d; up 8% sequentially • 2019 Exploration & Development capital guidance range lowered to $1.3 - 1.4 billion • Reduced per unit production expense 12% year-over-year DENVER, November 4, 2019 - Cimarex Energy Co. (NYSE: XEC)

Regulation FD Disclosure

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): November 4, 2019 CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporation) (Commission Fil

Director Emeritus Agreement dated September 30, 2019 between Cimarex Energy Co. and Michael J. Sullivan (filed on September 23, 2019 as Exhibit 10.1 to the Current Report on Form 8-K (Commission File No. 001-31446) and incorporated herein by reference). +

Exhibit 10.1 CIMAREX ENERGY CO. DIRECTOR EMERITUS AGREEMENT This Director Emeritus Agreement (this “Agreement”) is entered into by and between Cimarex Energy Co. (the “Company”), a Delaware corporation, and Michael J. Sullivan (“Mr. Sullivan”) effective September 30, 2019 (the “Effective Date”). WHEREAS, Michael J. Sullivan informed the Board of Directors of the Company (the “Board”) that he will

Regulation FD Disclosure

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities and Exchange Act of 1934 Date of Report (Date of earliest event reported): September 23, 2019 CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporation) (Commissi

Cimarex Announces Changes to its Board of Directors Kathleen Hogenson Joins Following the Retirement of Michael Sullivan

Exhibit 99.1 Cimarex Energy Co. 1700 Lincoln Street, Suite 3700 Denver, CO 80203 Phone: (303) 295-3995 Cimarex Announces Changes to its Board of Directors Kathleen Hogenson Joins Following the Retirement of Michael Sullivan DENVER, September 23, 2019 - Cimarex Energy Co. (NYSE: XEC) today announced the retirement of Michael J. Sullivan from its Board of Directors and the appointment of Kathleen A.

N E W S Cimarex Energy Co. 1700 Lincoln Street, Suite 3700 Denver, CO 80203 Phone: (303) 295-3995

N E W S Cimarex Energy Co. 1700 Lincoln Street, Suite 3700 Denver, CO 80203 Phone: (303) 295-3995 Cimarex Reports Second Quarter 2019 Results • Daily production averaged 274.8 MBOE; oil production averaged 83,430 barrels per day • 3Q oil production expected to be 85.0- 91.0 MBO/d; up 5.5 percent sequentially • 2019 oil production expected to grow 23-29 percent; led by the Permian region • 2019 cap

Regulation FD Disclosure

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): August 5, 2019 CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporation) (Commission File

Form of Notice of Grant of Nonqualified Stock Option and Award Agreement (filed on August 5, 2019 as Exhibit 10.5 to the Quarterly Report on Form 10-Q (Commission File No. 001-31446) and incorporated herein by reference). +

CIMAREX ENERGY CO. 1700 Lincoln Street, Suite 3700 Denver, Colorado 80203-4553 NOTICE OF GRANT OF NONQUALIFIED STOCK OPTION AND AWARD AGREEMENT Option Holder: Type of Option: Nonqualified stock option Date of Grant: Option Price per share: Number of shares: Expiration Date: 7 years from Date of Grant Vesting Schedule: One-third each year on anniversary of the Date of Grant By accepting this agreem

Form of Notice of Grant of Restricted Stock and Award Agreement (filed on August 5, 2019 as Exhibit 10.4 to the Quarterly Report on Form 10-Q (Commission File No. 001-31446) and incorporated herein by reference). +

CIMAREX ENERGY CO. 1700 Lincoln Street, Suite 3700 Denver, Colorado 80203-4553 NOTICE OF GRANT OF RESTRICTED STOCK AND AWARD AGREEMENT Restricted Stock Holder: Date of Grant: Number of Shares of Restricted Stock: Restriction Period Ends: By accepting this agreement online, you and Cimarex Energy Co. (the “Company”) agree that the Restricted Stock is granted under and governed by the terms and cond

Quarterly Report - 10-Q

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q (Mark One) ☒ Quarterly Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the Quarterly Period ended June 30, 2019 or ☐ Transition Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the transition period from to Commission File No. 001-31

XEC / Cimarex Energy Co. 11-K - - 11-K

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D C 20549 Form 11-K x ANNUAL REPORT PURSUANT TO SECTION 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2018 OR o TRANSITION REPORT PURSUANT TO SECTION 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission file number 001-31446 A.

Regulation FD Disclosure

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 Or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): June 11, 2019 CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporation) (Commission File N

XEC / Cimarex Energy Co. S-8 - - S-8

As filed with the United States Securities and Exchange Commission on May 30, 2019 Registration No.

2019 Equity Incentive Plan (filed on May 30, 2019 as Exhibit 99.1 to the Registration Statement on Form S-8 (Commission File No. 001-31446) and incorporated herein by reference).

Exhibit 99.1 CIMAREX ENERGY CO. 2019 EQUITY INCENTIVE PLAN Adopted by the Board on February 20, 2019 Approved by the Company’s stockholders on May 8, 2019 [6,317,476 shares total, consisting of 5,800,000 plus 517,476 available On May 8, 2019 under 2014 Equity Incentive Plan] 1. ESTABLISHMENT AND PURPOSE OF PLAN Cimarex Energy Co., a Delaware corporation (the “Company”), hereby establishes the Cima

Regulation FD Disclosure

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities and Exchange Act of 1934. Date of Report (Date of earliest event reported): May 28, 2019 CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporation) (Commission Fi

Form of Notice of Grant of Restricted Stock (Director) and Award Agreement (filed on May 29, 2019 as Exhibit 10.2 to the Current Report on Form 8-K (Commission File No. 001-31446) and incorporated herein by reference).

Exhibit 10.2 NOTICE OF GRANT OF RESTRICTED STOCK (DIRECTOR) AND AWARD AGREEMENT Name of Director Date of Grant June 1, 2019 Number of Shares of Restricted Stock [ ] Vesting Schedule Shares shall vest on the earlier to occur of (i) the termination of the service as a director other than because of removal or (ii) May 1, 2020 By accepting this agreement, you and Cimarex Energy Co. (the “Company”) ag

N E W S

Exhibit 99.1 N E W S Cimarex Energy Co. 1700 Lincoln Street, Suite 3700 Denver, CO 80203 Phone: (303) 295-3995 Cimarex Announces Changes to its Board of Directors: Paul N. Eckley Joins Following the Retirement of David Hentschel DENVER, May 28, 2019 - Cimarex Energy Co. (NYSE: XEC) today announced the retirement of David A. Hentschel from its Board of Directors and the appointment of Paul N. Eckle

Quarterly Report - 10-Q

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q (Mark One) ý Quarterly Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the Quarterly Period ended March 31, 2019 or o Transition Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the transition period from to Commission File No. 001-3

Submission of Matters to a Vote of Security Holders

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 Or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): May 8, 2019 CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporation) (Commission File Num

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): May 8, 2019 CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporation) (Commission File Num

N E W S Cimarex Energy Co. 1700 Lincoln Street, Suite 3700 Denver, CO 80203 Phone: (303) 295-3995

N E W S Cimarex Energy Co. 1700 Lincoln Street, Suite 3700 Denver, CO 80203 Phone: (303) 295-3995 Cimarex Reports First Quarter 2019 Results • Resolute acquisition closed • Daily production averaged 258.9 MBOE; oil production averaged 79,415 barrels per day • 2Q oil production expected to be up 4% sequentially at the midpoint of guidance • Oil production expected to grow 18-30% year over year • 20

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 Or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): March 25, 2019 CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporation) (Commission File

XEC / Cimarex Energy Co. DEFA14A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. ) Filed by the Registrant x Filed by a Party other than the Registrant o Check the appropriate box: o Preliminary Proxy Statement o Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) o Defin

XEC / Cimarex Energy Co. DEF 14A

Use these links to rapidly review the document TABLE OF CONTENTS Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.

Cimarex Announces Pricing of Senior Unsecured Notes

Exhibit 99.1 N E W S Cimarex Energy Co. 1700 Lincoln Street, Suite 3700 Denver, CO 80203 Phone: (303) 295-3995 Cimarex Announces Pricing of Senior Unsecured Notes DENVER, March 6, 2019 — Cimarex Energy Co. (NYSE: XEC) (“Cimarex”) announced today that it has priced an offering of $500 million aggregate principal amount of senior unsecured notes due 2029, which will carry an interest rate of 4.375 p

Underwriting Agreement dated March 6, 2019, by and among Cimarex Energy Co. and J.P. Morgan Securities LLC, MUFG Securities Americas Inc., and Wells Fargo Securities, LLC, as representatives of the several underwriters.

Exhibit 1.1 Execution Version $500,000,000 CIMAREX ENERGY CO. 4.375% Senior Notes due 2029 Underwriting Agreement March 6, 2019 J.P. Morgan Securities LLC 383 Madison Avenue New York, NY 10179 MUFG Securities Americas Inc. 1221 Avenue of the Americas, 6th Floor New York, NY 10005 Wells Fargo Securities, LLC 550 South Tryon Street, 5th Floor Charlotte, NC 28202 As Representatives of the several Und

Regulation FD Disclosure, Entry into a Material Definitive Agreement, Financial Statements and Exhibits, Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (date of earliest event reported): March 6, 2019 CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporation) (Commission File N

Second Supplemental Indenture dated as of March 8, 2019, by and between Cimarex Energy Co. and U.S. Bank National Association, as trustee (filed on March 8, 2019 as Exhibit 4.2 to the Current Report on Form 8-K (Commission File No. 001-31446) and incorporated herein by reference).

Exhibit 4.2 CIMAREX ENERGY CO. AND U.S. BANK NATIONAL ASSOCIATION, as Trustee 4.375% Senior Notes due 2029 SECOND SUPPLEMENTAL INDENTURE Dated as of March 8, 2019 to the INDENTURE Dated as of April 10, 2017 TABLE OF CONTENTS Page ARTICLE I SCOPE OF SUPPLEMENTAL INDENTURE; GENERAL; THE NOTES 2 SECTION 1.1. Scope of Supplemental Indenture; General 2 SECTION 1.2. Applicability of Sections of the Base

CALCULATION OF REGISTRATION FEE Title of Each Class of Securities to be Registered Proposed Maximum Aggregate Offering Price(1) Amount of Registration Fee 4.375% Senior Notes due 2029 $500,000,000 $60,600.00

Use these links to rapidly review the document Table of contents Table of contents Filed Pursuant to Rule 424(b)(5) Registration No.

Cimarex Energy Co. 4.375% Senior Notes due 2029

Filed Pursuant to Rule 433 Registration No. 333-230048 March 6, 2019 Pricing term sheet dated March 6, 2019 to Preliminary Prospectus Supplement dated March 6, 2019 (the “Preliminary Prospectus Supplement”) Cimarex Energy Co. $500,000,000 4.375% Senior Notes due 2029 The information in this pricing term sheet supplements the Preliminary Prospectus Supplement and supersedes the information in the P

Public offering price(1) Underwriting discounts Proceeds, before expenses, to us(1) Per note % % % Total $ $ $

424B5 1 a2237905z424b5.htm 424B5 Use these links to rapidly review the document Table of contents Table of contents Table of Contents Filed Pursuant to Rule 424(b)(5) Registration No. 333-230048 Subject to completion, dated March 6, 2019 This preliminary prospectus supplement relates to an effective registration statement under the Securities Act of 1933, but the information in this preliminary pr

Form T-1 Statement of Eligibility of Trustee.**

Exhibit 25.1 SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM T-1 STATEMENT OF ELIGIBILITY UNDER THE TRUST INDENTURE ACT OF 1939 OF A CORPORATION DESIGNATED TO ACT AS TRUSTEE Check if an Application to Determine Eligibility of a Trustee Pursuant to Section 305(b)(2) o U.S. BANK NATIONAL ASSOCIATION (Exact name of Trustee as specified in its charter) 31-0841368 I.R.S. Employer Identif

Registration Statement on Form S-3ASR (File No. 333-230048) filed on March 4, 2019

Use these links to rapidly review the document Table of contents Table of Contents As filed with the United States Securities and Exchange Commission on March 4, 2019 Registration No.

Cimarex announces closing of the acquisition of Resolute Energy

Exhibit 99.1 Cimarex announces closing of the acquisition of Resolute Energy DENVER, March 1, 2019 /PRNewswire/ — Cimarex Energy Co. (NYSE: XEC) announced that it completed its acquisition of Resolute Energy Corporation (NYSE: REN) (“Resolute”) on March 1, 2019. Resolute stockholders were able to elect to receive all cash, all stock or a combination of the two, subject to proration, so that the ag

Certificate of Designations of 8⅛% Series A Cumulative Perpetual Convertible Preferred Stock of Cimarex Energy Co., dated February 28, 2019 (filed on March 1, 2019 as Exhibit 3.1 to the Current Report on Form 8-K (Commission File No. 001-31446) and incorporated herein by reference).

Exhibit 3.1 CIMAREX ENERGY CO. CERTIFICATE OF DESIGNATIONS Pursuant to Section 151 of the General Corporation Law of the State of Delaware 81/8% SERIES A CUMULATIVE PERPETUAL CONVERTIBLE PREFERRED STOCK (Par Value $0.01 Per Share) Cimarex Energy Co. (the “Corporation”), a corporation organized and existing under the General Corporation Law of the State of Delaware (the “DGCL”), hereby certifies th

Completion of Acquisition or Disposition of Assets

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (date of earliest event reported): March 1, 2019 CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporation) (Commission File N

REN / Resolute Energy Corporation / Cimarex Energy Co - SC 13D/A Activist Investment

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13D Under the Securities Exchange Act of 1934 (Amendment No. 2) RESOLUTE ENERGY CORPORATION (Name of Issuer) Common Stock, par value of $0.0001 per share (Title of Class of Securities) 76116A306 (CUSIP Number) Francis B. Barron Senior Vice President — General Counsel Cimarex Energy Co. 1700 Lincoln Street, Suite 3700

REN / Resolute Energy Corporation / Cimarex Energy Co - SC 13D/A Activist Investment

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13D Under the Securities Exchange Act of 1934 (Amendment No. 1) RESOLUTE ENERGY CORPORATION (Name of Issuer) Common Stock, par value of $0.0001 per share (Title of Class of Securities) 76116A306 (CUSIP Number) Francis B. Barron Senior Vice President — General Counsel Cimarex Energy Co. 1700 Lincoln Street, Suite 3700

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): February 20, 2019 CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporation) (Commission Fi

N E W S Cimarex Energy Co. 1700 Lincoln Street, Suite 3700 Denver, CO 80203 Phone: (303) 295-3995

N E W S Cimarex Energy Co. 1700 Lincoln Street, Suite 3700 Denver, CO 80203 Phone: (303) 295-3995 Cimarex Reports Fourth Quarter and Full Year 2018 Results • 4Q daily production above guidance averaging 251.3 MBOE; 79,904 barrels of oil • Daily production for the full year averaged 221.9 MBOE; 67,699 barrels of oil • 2018 E&D expenditures below guidance at $1.57 billion • Cimarex sold assets in Wa

N E W S Cimarex Energy Co. 1700 Lincoln Street, Suite 3700 Denver, CO 80203 Phone: (303) 295-3995

N E W S Cimarex Energy Co. 1700 Lincoln Street, Suite 3700 Denver, CO 80203 Phone: (303) 295-3995 Cimarex Releases 2019 Capital Investment Plans and Production and Expense Guidance • Exploration & development capital investment estimated at $1.35 - 1.45 billion – Includes drilling and completion capital of $1.1-1.2 billion • Generates year-over-year production growth of 13-22% – Led by oil growth

XEC / Cimarex Energy Co. 10-K (Annual Report)

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Form 10-K (Mark One) ý ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2018 OR o TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Commission file number 001-31446 CIMAREX ENERGY CO. (Exact name

Power of Attorney of directors of the Registrant. *

Exhibit 24.1 POWER OF ATTORNEY KNOW ALL MEN BY THESE PRESENTS, that each person whose signature appears below hereby constitutes and appoints Thomas E. Jorden and G. Mark Burford and each of them acting alone, his true and lawful attorney-in-fact and agent, with full power of substitution and revocation, for him in any and all capacities, to execute and cause to be filed with the Securities and Ex

Form of Notice of Grant of Restricted Stock and Award Agreement (Performance Award) (filed as Exhibit 10.35 to the Annual Report on Form 10-K for the year ended December 31, 2018 filed on February 20, 2019 (Commission File No. 001-31446) and incorporated herein by reference). +

CIMAREX ENERGY CO. 1700 Lincoln Street, Suite 3700 Denver, Colorado 80203-4537 NOTICE OF GRANT OF RESTRICTED STOCK AND AWARD AGREEMENT (PERFORMANCE AWARD) Name: Participant ID: Plan: 2014 Equity Incentive Plan Date of Award: December 6, 2018 Number of shares: Restriction Period Ends: December 1, 2021 By accepting this agreement online, you and Cimarex Energy Co. (the “Company”) agree that this res

Significant subsidiaries of the Registrant. *

EX-21.1 3 a12311810kex-211xec.htm EXHIBIT 21.1 Exhibit 21.1 List of Significant Subsidiaries Cimarex Energy Co. of Colorado, a Texas corporation Cimarex Gas Gathering, Inc., a Texas corporation Key Production Company, Inc., a Delaware corporation Magnum Hunter Production, Inc., a Texas corporation Oklahoma Gas Processing, Inc., a Delaware corporation Prize Energy Resources, Inc., a Delaware corpor

Letter dated January 21, 2019 from DeGolyer and MacNaughton, independent petroleum engineering consulting firm, reporting the results of its audit of Cimarex reserves as of December 31, 2018 of certain selected properties. *

DeGolyer and MacNaughton 5001 Spring Valley Road Suite 800 East Dallas, Texas 75244 Exhibit 99.

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (date of earliest event reported): February 14, 2019 CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporation) (Commission Fi

XEC / Cimarex Energy Co. 8-K (Prospectus)

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (date of earliest event reported): February 14, 2019 CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporation) (Commission Fi

XEC / Cimarex Energy Co. / Boston Partners - ROBECO INVESTMENT MANAGEMENT INC. Passive Investment

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 CIMAREX ENERGY CO (Name of Issuer) Common Stock (Title of Class of Securities) 171798101 (CUSIP Number) December 31, 2018 (Date of Event which Requires Filing of this Statement) Check the appropriate box to designate the rule pursuant to which this Schedule is filed: [X] R

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): February 11, 2019 CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporation) (Commission Fi

Cimarex Energy and Resolute Energy Announce February 22nd Deadline for Resolute Stockholder’s Election of Form of Merger Consideration

Exhibit 99.1 Cimarex Energy and Resolute Energy Announce February 22nd Deadline for Resolute Stockholder’s Election of Form of Merger Consideration DENVER, CO, February 11, 2019 — Cimarex Energy Co. (NYSE: XEC) (“Cimarex”) and Resolute Energy Corporation (NYSE: REN) (“Resolute”) today announced that, in connection with Cimarex’s pending acquisition of Resolute, the election deadline for holders of

Cimarex Energy and Resolute Energy Announce February 22nd Deadline for Resolute Stockholder’s Election of Form of Merger Consideration

Exhibit 99.1 Cimarex Energy and Resolute Energy Announce February 22nd Deadline for Resolute Stockholder’s Election of Form of Merger Consideration DENVER, CO, February 11, 2019 — Cimarex Energy Co. (NYSE: XEC) (“Cimarex”) and Resolute Energy Corporation (NYSE: REN) (“Resolute”) today announced that, in connection with Cimarex’s pending acquisition of Resolute, the election deadline for holders of

XEC / Cimarex Energy Co. 8-K (Prospectus)

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): February 11, 2019 CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporation) (Commission Fi

XEC / Cimarex Energy Co. / VANGUARD GROUP INC Passive Investment

cimarexenergyco.htm - Generated by SEC Publisher for SEC Filing SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Schedule 13G Under the Securities Exchange Act of 1934 (Amendment No.: 5 )* Name of issuer: Cimarex Energy Co Title of Class of Securities: Common Stock CUSIP Number: 171798101 Date of Event Which Requires Filing of this Statement: December 31, 2018 Check the appropriate box to

Amended and Restated Credit Agreement, dated February 5, 2019, among the Company, as borrower, JPMorgan Chase Bank, N.A., as administrative agent, Wells Fargo Bank, N.A., as syndication agent, the co-documentation agents party thereto, J.P. Morgan Chase Bank, N.A. and Wells Fargo Securities, LLC, as lead arrangers and bookrunners, and the lenders party thereto. (filed as Exhibit 10.1 to the Current Report on Form 8-K filed February 7, 2019 (Commission File No. 001-31446) and incorporated herein by reference).

Exhibit 10.1 AMENDED AND RESTATED CREDIT AGREEMENT dated as of February 5, 2019 among CIMAREX ENERGY CO., as the Borrower, JPMORGAN CHASE BANK, N.A., as the Administrative Agent for the Lenders, WELLS FARGO BANK, N.A., as the Syndication Agent for the Lenders, BMO HARRIS BANK, N.A., COMPASS BANK, MUFG UNION BANK, N.A., PNC BANK, NATIONAL ASSOCIATION, THE BANK OF NOVA SCOTIA, HOUSTON BRANCH and U.S

Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (date of earliest event reported): February 7, 2019 (February 5, 2019) CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of (Commission

PROPOSED MERGER—YOUR VOTE IS VERY IMPORTANT

Use these links to rapidly review the document CONTENTS TABLE OF CONTENTS Table of Contents Filed Pursuant to Rule 424(b)(3) Registration No.

Form of Proxy for Resolute Energy Corporation

Exhibit 99.1 RESOLUTE ENERGY CORPORATION YOUR VOTE IS IMPORTANT. PLEASE VOTE TODAY. We encourage you to take advantage of Internet or telephone voting. Both are available 24 hours a day, 7 days a week. Internet and telephone voting is available through 11:59 p.m., Eastern Time the day before the special meeting date. VOTE BY INTERNET – WWW.CESVOTE.COM Use the Internet to transmit your voting instr

Form of Election Form

Exhibit 99.2 PRELIMINARY – SUBJECT TO COMPLETION FORM OF ELECTION FORM AND LETTER OF TRANSMITTAL TIME SENSITIVE INFORMATION. YOUR IMMEDIATE ATTENTION IS NECESSARY. PLEASE COMPLETE AND RETURN PROMPTLY IN ACCORDANCE WITH THE ENCLOSED INSTRUCTIONS. Ladies and Gentlemen: The following Election Form and Letter of Transmittal and accompanying instructions (the “Election Form”) are for the holders of sha

Form of Certificate of Designations of 81/8% Series A Cumulative Perpetual Convertible Preferred Stock of Cimarex Energy Co.

EX-3.3 2 a2237506zex-33.htm EX-3.3 Exhibit 3.3 CIMAREX ENERGY CO. CERTIFICATE OF DESIGNATIONS Pursuant to Section 151 of the General Corporation Law of the State of Delaware 81/8% SERIES A CUMULATIVE PERPETUAL CONVERTIBLE PREFERRED STOCK (Par Value $0.01 Per Share) Cimarex Energy Co. (the “Corporation”), a corporation organized and existing under the General Corporation Law of the State of Delawar

XEC / Cimarex Energy Co. S-4/A

Use these links to rapidly review the document CONTENTS TABLE OF CONTENTS Table of Contents As filed with the Securities and Exchange Commission on January 10, 2019 Registration No.

XEC / Cimarex Energy Co. S-4

Use these links to rapidly review the document CONTENTS TABLE OF CONTENTS Table of Contents As filed with the Securities and Exchange Commission on December 14, 2018 Registration No.

XEC / Cimarex Energy Co. 425 (Prospectus)

Filed by Cimarex Energy Co. (Commission File No. 001-31446) Pursuant to Rule 425 under the Securities Act of 1933, as amended and deemed filed pursuant to Rule 14a-12 of the Securities Exchange Act of 1934, as amended Subject Company: Resolute Energy Corporation (Commission File No. 001-34464) Date: November 29, 2018 Presentation Resolute Employees November2018 Safe Harbor Cautionary Statements Re

REN / Resolute Energy Corporation / Cimarex Energy Co - SC 13D Activist Investment

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13D Under the Securities Exchange Act of 1934 RESOLUTE ENERGY CORPORATION (Name of Issuer) Common Stock, par value of $0.0001 per share (Title of Class of Securities) 76116A306 (CUSIP Number) Francis B. Barron Senior Vice President — General Counsel Cimarex Energy Co. 1700 Lincoln Street, Suite 3700 Denver, Colorado 8

Voting Agreement, dated as of November 18, 2018, by and between Cimarex Energy Co. and Nicholas J. Sutton (incorporated herein by reference to Exhibit 10.5 to Cimarex Energy Co.'s Current Report on Form 8-K filed on November 20, 2018) (Commission File No. 001-31446)

Exhibit 10.5 VOTING AND SUPPORT AGREEMENT This VOTING AGREEMENT, dated as of November 18, 2018 (this “Agreement”), is entered into by and among Cimarex Energy Co., a Delaware corporation (“Parent”), and the undersigned signatory set forth on the signature pages hereto under the heading “Company Stockholder” (“Company Stockholder”). Parent and Company Stockholder are each sometimes referred to here

Voting Agreement, dated as of November 18, 2018, by and between Cimarex Energy Co. and Richard Betz (incorporated herein by reference to Exhibit 10.4 to Cimarex Energy Co.'s Current Report on Form 8-K filed on November 20, 2018) (Commission File No. 001-31446)

Exhibit 10.4 VOTING AND SUPPORT AGREEMENT This VOTING AGREEMENT, dated as of November 18, 2018 (this “Agreement”), is entered into by and among Cimarex Energy Co., a Delaware corporation (“Parent”), and the undersigned signatory set forth on the signature pages hereto under the heading “Company Stockholder” (“Company Stockholder”). Parent and Company Stockholder are each sometimes referred to here

Agreement and Plan of Merger dated as of November 18, 2018, by and among Cimarex Energy Co., CR Sub 1 Inc., CR Sub 2 LLC and Resolute Energy Corporation (filed as Exhibit 2.1 to Registrant’s Form 8-K (Commission File No. 001-31446) dated November 20, 2018 and incorporated herein by reference).

Exhibit 2.1 AGREEMENT AND PLAN OF MERGER by and among CIMAREX ENERGY CO., CR SUB 1 INC., CR SUB 2 LLC and RESOLUTE ENERGY CORPORATION Dated as of November 18, 2018 TABLE OF CONTENTS Page ARTICLE I CERTAIN DEFINITIONS 2 1.1 Certain Definitions 2 ARTICLE II THE MERGER 2 2.1 The First Merger 2 2.2 The Second Merger 2 2.3 Closing 3 2.4 Organizational Documents of the Surviving Corporation and the Surv

Entry into a Material Definitive Agreement, Financial Statements and Exhibits

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (date of earliest event reported): November 18, 2018 CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporation) (Commission Fi

Voting Agreement, dated as of November 18, 2018, by and between Cimarex Energy Co. and Theodore Gazulis (incorporated herein by reference to Exhibit 10.6 to Cimarex Energy Co.'s Current Report on Form 8-K filed on November 20, 2018) (Commission File No. 001-31446)

Exhibit 10.6 VOTING AND SUPPORT AGREEMENT This VOTING AGREEMENT, dated as of November 18, 2018 (this “Agreement”), is entered into by and among Cimarex Energy Co., a Delaware corporation (“Parent”), and the undersigned signatory set forth on the signature pages hereto under the heading “Company Stockholder” (“Company Stockholder”). Parent and Company Stockholder are each sometimes referred to here

Voting Agreement, dated as of November 18, 2018, by and among Cimarex Energy Co., John C. Goff and certain other related entities thereto (incorporated herein by reference to Exhibit 10.2 to Cimarex Energy Co.'s Current Report on Form 8-K filed on November 20, 2018) (Commission File No. 001-31446)

Exhibit 10.2 VOTING AND SUPPORT AGREEMENT This VOTING AGREEMENT, dated as of November 18, 2018 (this “Agreement”), is entered into by and among Cimarex Energy Co., a Delaware corporation (“Parent”), and the undersigned signatories set forth on the signature pages hereto under the heading “Company Stockholders” (collectively, the “Company Stockholders”). Parent and the Company Stockholders are each

Voting Agreement, dated as of November 18, 2018, by and among Cimarex Energy Co. and Monarch Alternative Capital LP, MDRA GP LP and Monarch GP LLC (incorporated herein by reference to Exhibit 10.1 to Cimarex Energy Co.'s Current Report on Form 8-K filed on November 20, 2018) (Commission File No. 001-31446)

Exhibit 10.1 VOTING AND SUPPORT AGREEMENT This VOTING AGREEMENT, dated as of November 18, 2018 (this “Agreement”), is entered into by and among Cimarex Energy Co., a Delaware corporation (“Parent”), and the undersigned signatories set forth on the signature pages hereto under the heading “Company Stockholders” (collectively, the “Company Stockholders”). Parent and the Company Stockholders are each

Voting Agreement, dated as of November 18, 2018, by and between Cimarex Energy Co. and RR Advisors, LLC (incorporated herein by reference to Exhibit 10.3 to Cimarex Energy Co.'s Current Report on Form 8-K filed on November 20, 2018) (Commission File No. 001-31446)

Exhibit 10.3 VOTING AND SUPPORT AGREEMENT This VOTING AGREEMENT, dated as of November 18, 2018 (this “Agreement”), is entered into by and among Cimarex Energy Co., a Delaware corporation (“Parent”), and the undersigned signatories set forth on the signature pages hereto under the heading “Company Stockholders” (collectively, the “Company Stockholders”; provided that if there is only one Company St

Voting Agreement, dated as of November 18, 2018, by and among Cimarex Energy Co., John C. Goff and certain other related entities thereto.

Exhibit 10.2 VOTING AND SUPPORT AGREEMENT This VOTING AGREEMENT, dated as of November 18, 2018 (this “Agreement”), is entered into by and among Cimarex Energy Co., a Delaware corporation (“Parent”), and the undersigned signatories set forth on the signature pages hereto under the heading “Company Stockholders” (collectively, the “Company Stockholders”). Parent and the Company Stockholders are each

Voting Agreement, dated as of November 18, 2018, by and between Cimarex Energy Co. and Theodore Gazulis.

Exhibit 10.6 VOTING AND SUPPORT AGREEMENT This VOTING AGREEMENT, dated as of November 18, 2018 (this “Agreement”), is entered into by and among Cimarex Energy Co., a Delaware corporation (“Parent”), and the undersigned signatory set forth on the signature pages hereto under the heading “Company Stockholder” (“Company Stockholder”). Parent and Company Stockholder are each sometimes referred to here

Voting Agreement, dated as of November 18, 2018, by and between Cimarex Energy Co. and RR Advisors, LLC.

Exhibit 10.3 VOTING AND SUPPORT AGREEMENT This VOTING AGREEMENT, dated as of November 18, 2018 (this “Agreement”), is entered into by and among Cimarex Energy Co., a Delaware corporation (“Parent”), and the undersigned signatories set forth on the signature pages hereto under the heading “Company Stockholders” (collectively, the “Company Stockholders”; provided that if there is only one Company St

Agreement and Plan of Merger, dated as of November 18, 2018, by and among Cimarex Energy Co., CR Sub 1 Inc., CR Sub 2 LLC and Resolute Energy Corporation.*

Exhibit 2.1 AGREEMENT AND PLAN OF MERGER by and among CIMAREX ENERGY CO., CR SUB 1 INC., CR SUB 2 LLC and RESOLUTE ENERGY CORPORATION Dated as of November 18, 2018 TABLE OF CONTENTS Page ARTICLE I CERTAIN DEFINITIONS 2 1.1 Certain Definitions 2 ARTICLE II THE MERGER 2 2.1 The First Merger 2 2.2 The Second Merger 2 2.3 Closing 3 2.4 Organizational Documents of the Surviving Corporation and the Surv

Voting Agreement, dated as of November 18, 2018, by and between Cimarex Energy Co. and Richard Betz.

Exhibit 10.4 VOTING AND SUPPORT AGREEMENT This VOTING AGREEMENT, dated as of November 18, 2018 (this “Agreement”), is entered into by and among Cimarex Energy Co., a Delaware corporation (“Parent”), and the undersigned signatory set forth on the signature pages hereto under the heading “Company Stockholder” (“Company Stockholder”). Parent and Company Stockholder are each sometimes referred to here

XEC / Cimarex Energy Co. 8-K (Prospectus)

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (date of earliest event reported): November 18, 2018 CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporation) (Commission Fi

Voting Agreement, dated as of November 18, 2018, by and between Cimarex Energy Co. and Nicholas J. Sutton.

Exhibit 10.5 VOTING AND SUPPORT AGREEMENT This VOTING AGREEMENT, dated as of November 18, 2018 (this “Agreement”), is entered into by and among Cimarex Energy Co., a Delaware corporation (“Parent”), and the undersigned signatory set forth on the signature pages hereto under the heading “Company Stockholder” (“Company Stockholder”). Parent and Company Stockholder are each sometimes referred to here

Voting Agreement, dated as of November 18, 2018, by and among Cimarex Energy Co. and Monarch Alternative Capital LP, MDRA GP LP and Monarch GP LLC.

Exhibit 10.1 VOTING AND SUPPORT AGREEMENT This VOTING AGREEMENT, dated as of November 18, 2018 (this “Agreement”), is entered into by and among Cimarex Energy Co., a Delaware corporation (“Parent”), and the undersigned signatories set forth on the signature pages hereto under the heading “Company Stockholders” (collectively, the “Company Stockholders”). Parent and the Company Stockholders are each

XEC / Cimarex Energy Co. 425 (Prospectus)

Filed by Cimarex Energy Co. (Commission File No. 001-31446) Pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-12 of the Securities Exchange Act of 1934 Subject Company: Resolute Energy Corporation (Commission File No. 001-34464) On November 18, 2019, Cimarex Energy Co. (“Cimarex” or the “Company”) hosted a conference call regarding the Company’s pending ac

Cimarex to Acquire Delaware Pure-Play Resolute for $1.6 billion

Exhibit 99.1 Cimarex to Acquire Delaware Pure-Play Resolute for $1.6 billion · Cash and stock acquisition consistent with disciplined, returns-driven approach · Expected to be accretive to EPS and non-GAAP CFPS in 2019 · Expands Cimarex’s footprint in Reeves County by 21,100 net acres · Adds 35 MBOE/D (45% oil) to Cimarex’s production base DENVER, CO, November 19, 2018 — Cimarex (NYSE: XEC) and Re

Bolt-On Acquisition in Permian Basin $1.6B Transaction Value, incl. assumption of $710MM of Debt Cash and Stock Consideration 40% 60% Cash Stock REN Shareholders own 5.6% of XEC shares post closing 1Q 2019 Expected Close Transaction Metrics Compare F

Exhibit 99.3 Bolt-On Acquisition in Permian Basin $1.6B Transaction Value, incl. assumption of $710MM of Debt Cash and Stock Consideration 40% 60% Cash Stock REN Shareholders own 5.6% of XEC shares post closing 1Q 2019 Expected Close Transaction Metrics Compare Favorably with Recent Delaware Basin Deals $31,000 – $37,000 Price Paid per Flowing BOE* Implied Price per Acre paid by XEC (mid-point) $2

Acquisition of Resolute Energy Corporation November 2018

Exhibit 99.2 Acquisition of Resolute Energy Corporation November 2018 Safe Harbor Cautionary Statements Regarding Forward-Looking Information This presentation contains certain “forward-looking statements” within the meaning of federal securities laws. Words such as “anticipates,” “believes,” “expects,” “intends,” “will,” “should,” “may” and similar expressions may be used to identify forward-look

Regulation FD Disclosure, Financial Statements and Exhibits, Other Events

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (date of earliest event reported): November 19, 2018 CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporation) (Commission Fi

XEC / Cimarex Energy Co. 8-K (Prospectus)

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (date of earliest event reported): November 19, 2018 CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporation) (Commission Fi

Acquisition of Resolute Energy Corporation November 2018

Exhibit 99.2 Acquisition of Resolute Energy Corporation November 2018 Safe Harbor Cautionary Statements Regarding Forward-Looking Information This presentation contains certain “forward-looking statements” within the meaning of federal securities laws. Words such as “anticipates,” “believes,” “expects,” “intends,” “will,” “should,” “may” and similar expressions may be used to identify forward-look

Bolt-On Acquisition in Permian Basin $1.6B Transaction Value, incl. assumption of $710MM of Debt Cash and Stock Consideration 40% 60% Cash Stock REN Shareholders own 5.6% of XEC shares post closing 1Q 2019 Expected Close Transaction Metrics Compare F

Exhibit 99.3 Bolt-On Acquisition in Permian Basin $1.6B Transaction Value, incl. assumption of $710MM of Debt Cash and Stock Consideration 40% 60% Cash Stock REN Shareholders own 5.6% of XEC shares post closing 1Q 2019 Expected Close Transaction Metrics Compare Favorably with Recent Delaware Basin Deals $31,000 – $37,000 Price Paid per Flowing BOE* Implied Price per Acre paid by XEC (mid-point) $2

Cimarex to Acquire Delaware Pure-Play Resolute for $1.6 billion

EX-99.1 2 a18-404141ex99d1.htm EX-99.1 Exhibit 99.1 Cimarex to Acquire Delaware Pure-Play Resolute for $1.6 billion · Cash and stock acquisition consistent with disciplined, returns-driven approach · Expected to be accretive to EPS and non-GAAP CFPS in 2019 · Expands Cimarex’s footprint in Reeves County by 21,100 net acres · Adds 35 MBOE/D (45% oil) to Cimarex’s production base DENVER, CO, Novembe

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): November 9, 2018 CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporation) (Commission Fil

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K/A (Amendment No. 1) CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): November 6, 2018 CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporat

N E W S Cimarex Energy Co. 1700 Lincoln Street, Suite 3700 Denver, CO 80203 Phone: (303) 295-3995

N E W S Cimarex Energy Co. 1700 Lincoln Street, Suite 3700 Denver, CO 80203 Phone: (303) 295-3995 Cimarex Reports Third Quarter 2018 Results • Daily production averaged 218.6 MBOE; oil production averaged 63,909 barrels per day • 2018 capital guidance unchanged; targeting mid point • Fourth quarter oil production expected to average 73.0 - 78.0 MBbls per day DENVER, November 6, 2018 - Cimarex Ener

N E W S Cimarex Energy Co. 1700 Lincoln Street, Suite 3700 Denver, CO 80203 Phone: (303) 295-3995

N E W S Cimarex Energy Co. 1700 Lincoln Street, Suite 3700 Denver, CO 80203 Phone: (303) 295-3995 Cimarex Reports Third Quarter 2018 Results • Daily production averaged 218.6 MBOE; oil production averaged 63,909 barrels per day • 2018 capital guidance unchanged; targeting mid point • Fourth quarter oil production expected to average 73.0 - 78.0 MBbls per day DENVER, November 6, 2018 - Cimarex Ener

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): November 6, 2018 CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporation) (Commission Fil

XEC / Cimarex Energy Co. 10-Q (Quarterly Report)

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q (Mark One) ý Quarterly Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the Quarterly Period ended September 30, 2018 or o Transition Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the transition period from to Commission File No. 0

N E W S Cimarex Energy Co. 1700 Lincoln Street, Suite 3700 Denver, CO 80203 Phone: (303) 295-3995

N E W S Cimarex Energy Co. 1700 Lincoln Street, Suite 3700 Denver, CO 80203 Phone: (303) 295-3995 Cimarex Announces Closing of Ward County Asset Sale DENVER, September 4, 2018 - Cimarex Energy Co. (NYSE: XEC) today announced the August 31, 2018 closing of the previously announced sale of assets in Ward County, Texas, for $544.5 million, adjusted to reflect the resolution of all asserted defects. P

Completion of Acquisition or Disposition of Assets

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): August 31, 2018 CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporation) (Commission File

CIMAREX ENERGY CO. INTRODUCTION TO THE UNAUDITED PRO FORMA CONDENSED CONSOLIDATED FINANCIAL STATEMENTS

Exhibit 99.1 CIMAREX ENERGY CO. INTRODUCTION TO THE UNAUDITED PRO FORMA CONDENSED CONSOLIDATED FINANCIAL STATEMENTS On May 23, 2018, Cimarex Energy Co. (“Cimarex,” “we,” or “us”) entered into a Purchase and Sale Agreement with Callon Petroleum Operating Company (“Callon”) pursuant to which we agreed to sell, and Callon agreed to purchase, oil and gas properties principally located in Ward County,

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): August 7, 2018 CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporation) (Commission File

N E W S Cimarex Energy Co. 1700 Lincoln Street, Suite 3700 Denver, CO 80203 Phone: (303) 295-3995

EX-99.1 2 a20180630xecpressrelease.htm EXHIBIT 99.1 N E W S Cimarex Energy Co. 1700 Lincoln Street, Suite 3700 Denver, CO 80203 Phone: (303) 295-3995 Cimarex Reports Second Quarter 2018 Results • Daily production averaged 211.4 MBOE; oil production up seven percent year-over-year • 2018 capital guidance unchanged ◦ Oil production expected to grow 20-25 percent year-over-year • Ward County asset sa

XEC / Cimarex Energy Co. 10-Q (Quarterly Report)

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q (Mark One) ý Quarterly Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the Quarterly Period ended June 30, 2018 or o Transition Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the transition period from to Commission File No. 001-31

XEC / Cimarex Energy Co. 11-K

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D C 20549 Form 11-K x ANNUAL REPORT PURSUANT TO SECTION 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2017 OR o TRANSITION REPORT PURSUANT TO SECTION 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission file number 001-31446 A.

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 Or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): May 25, 2018 CIMAREX ENERGY CO. (Exact name of registrant as specified in its charter) Delaware 001-31446 45-0466694 (State or other jurisdiction of incorporation) (Commission File Nu

Cimarex Agrees to Sell Ward County Assets for $570 million

Exhibit 99.1 Cimarex Energy Co. 1700 Lincoln Street, Suite 3700 Denver, CO 80203 Phone: (303) 295-3995 N E W S Cimarex Agrees to Sell Ward County Assets for $570 million DENVER, May 24, 2018 - Cimarex Energy Co. (NYSE: XEC) announced today that it has signed a purchase and sale agreement to sell oil and gas properties principally located in Ward County, Texas, for $570 million in cash to Callon Pe