The remainder of this cover page shall be filled out for a reporting person’s initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter the disclosures provided in a prior cover page.

Name of Reporting Person

QStar LLC

Check the Appropriate Box if a Member of a Group

(a)  ☐        (b)  ☐

SEC Use Only

Citizenship or Place of Organization

Delaware

Number of

Shares

Beneficially

Owned by

Each

Reporting

Person

With

Sole Voting Power

5,971,610

Shared Voting Power

0

Sole Dispositive Power

5,971,610

Shared Dispositive Power

0

Aggregate Amount Beneficially Owned by Each Reporting Person

5,971,610

Check if the Aggregate Amount in Row (9) Excludes Certain Shares  ☐

Percent of Class Represented by Amount in Row (9)

5.3% (1)

Type of Reporting Person

OO (Limited Liability Company)

Based on 112,142,751 shares of common stock, par value $0.01 per share (“Common Stock”) of SM Energy Company, a Delaware corporation (the “Issuer”), issued and outstanding as of October 24, 2018, as set forth in the Issuer’s Quarterly Report on Form 10-Q for the quarter ended September 30, 2018, filed with the Securities and Exchange Commission (the “SEC”) on November 2, 2018.

Name of Reporting Person

EnCap Energy Capital Fund IX, L.P.

Check the Appropriate Box if a Member of a Group

(a)  ☐        (b)  ☐

SEC Use Only

Citizenship or Place of Organization

Texas

Number of

Shares

Beneficially

Owned by

Each

Reporting

Person

With

Sole Voting Power

5,971,610

Shared Voting Power

0

Sole Dispositive Power

5,971,610

Shared Dispositive Power

0

Aggregate Amount Beneficially Owned by Each Reporting Person

5,971,610 (1)

Check if the Aggregate Amount in Row (9) Excludes Certain Shares  ☐

Percent of Class Represented by Amount in Row (9)

5.3% (2)

Type of Reporting Person

OO (Limited Partnership)

Includes 5,971,610 shares of Common Stock owned by QStar LLC (“QStar”). EnCap Energy Capital Fund IX, L.P. (“EnCap Fund IX”) is a member of QStar that holds the right to appoint three of the five managers of the board of managers of QStar and has the sole power to vote or direct the vote or to dispose or direct the disposition of the Common Stock owned by QStar. EnCap Fund IX disclaims beneficial ownership of the securities owned by QStar in excess of its pecuniary interest therein.

Based on 112,142,751 shares of Common Stock, issued and outstanding as of October 24, 2018, as set forth in the Issuer’s Quarterly Report on Form 10-Q for the quarter ended September 30, 2018, filed with the SEC on November 2, 2018.

Name of Reporting Person

EnCap Partners GP, LLC

Check the Appropriate Box if a Member of a Group

(a)  ☐        (b)  ☐

SEC Use Only

Citizenship or Place of Organization

Delaware

Number of

Shares

Beneficially

Owned by

Each

Reporting

Person

With

Sole Voting Power

5,971,610

Shared Voting Power

0

Sole Dispositive Power

5,971,610

Shared Dispositive Power

0

Aggregate Amount Beneficially Owned by Each Reporting Person

5,971,610 (1)

Check if the Aggregate Amount in Row (9) Excludes Certain Shares  ☐

Percent of Class Represented by Amount in Row (9)

5.3% (2)

Type of Reporting Person

OO (Limited Liability Company)

Includes 5,971,610 shares of Common Stock owned by QStar. EnCap Partners GP, LLC (“EnCap Partners GP”) is the sole general partner of EnCap Partners, LP (“EnCap Partners”), which is the managing member of EnCap Investments Holdings, LLC (“EnCap Holdings”), which is the sole member of EnCap Investments Holdings Blocker, LLC (“EnCap Holdings Blocker”). EnCap Holdings Blocker is the sole member of EnCap Investments GP, L.L.C. (“EnCap Investments GP”), which is the sole general partner of EnCap Investments L.P. (“EnCap Investments LP”). EnCap Investments LP is the sole general partner of EnCap Equity Fund IX GP, L.P. (“EnCap Fund IX GP”), which is the sole general partner of EnCap Fund IX. EnCap Fund IX is a member of QStar that holds the right to appoint three of the five managers of the board of managers of QStar and has the sole power to vote or direct the vote or to dispose or direct the disposition of the Common Stock owned by QStar. EnCap Partners GP, EnCap Partners, EnCap Holdings, EnCap Holdings Blocker, EnCap Investments GP, EnCap Investments LP, EnCap Fund IX GP and EnCap Fund IX disclaim beneficial ownership of the securities owned by QStar except to the extent of their respective pecuniary interest therein, and this statement shall not be deemed an admission that any of EnCap Partners GP, EnCap Partners, EnCap Holdings, EnCap Holdings Blocker, EnCap Investments GP, EnCap Investments LP and EnCap Fund IX GP is the beneficial owner of the reported Common Stock for the purposes of Section 13(d) of the Securities Exchange Act of 1934, as amended, or any other purpose.

Based on 112,142,751 shares of Common Stock, issued and outstanding as of October 24, 2018, as set forth in the Issuer’s Quarterly Report on Form 10-Q for the quarter ended September 30, 2018, filed with the SEC on November 2, 2018.

Name of issuer:

Address of issuer’s principal executive offices:

Names of persons filing:

QStar LLC, a Delaware limited liability company

EnCap Energy Capital Fund IX, L.P., a Texas limited partnership

EnCap Partners GP, LLC, a Delaware limited liability company

Address or principal business office or, if none, residence of each Reporting Person is:

Citizenship:

Title of class of securities:

CUSIP number:

If this statement is filed pursuant to Rule 13d-1(b), or 13d-2(b) or (c), check whether the person filing is a:

Ownership:

Ownership of five percent or less of a class:

Ownership of more than five percent on behalf of another person:

Identification and classification of the subsidiary which acquired the security being reported on by the parent holding company or control person:

Identification and classification of members of the group:

Notice of dissolution of group:

Certifications:

Exhibit

    No.    

Description