UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, DC 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 15, 2018

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below):

☐ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company  ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13a of the Exchange Act.  ☐

Item 1.01. Entry into a Material Definitive Agreement

On October 15, 2018, Carbon Energy Corporation, a Delaware corporation (“Carbon” or the “Company”), entered into an amendment (the “Amendment”) of that certain Membership Interest Purchase Agreement (as amended, supplemented or otherwise modified to date, the “Purchase Agreement”) by and among the Company, Old Ironsides Energy Fund II-A Portfolio Holding Company, LLC, a Delaware limited liability company (“OIE II-A”), and Old Ironsides Energy Fund II-B Portfolio Holding Company, LLC, a Delaware limited liability company (together with OIE II-A, the “Sellers”) dated May 4, 2018. The Amendment extends the date after which either Carbon or the Sellers may exercise certain termination rights from October 15, 2018 to November 6, 2018.

A copy of the Amendment is attached as Exhibit 10.1 to this Current Report on Form 8-K. The material terms of the Purchase Agreement are described in the Current Report on Form 8-K previously filed with the Securities and Exchange Commission on May 4, 2018. The description of the Amendment in this Current Report on Form 8-K is a summary and is qualified in its entirety by reference to the complete text of the Amendment.

Item 9.01. Financial Statements and Exhibits

(d) Exhibits.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this Current Report on Form 8-K to be signed on its behalf by the undersigned, hereunto duly authorized.

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