SC 13G/A

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 13G

Under the Securities Exchange Act of 1934

(Amendment No. 1)*

SM ENERGY COMPANY

(Name of Issuer)

COMMON STOCK, PAR VALUE $0.01 PER SHARE

(Title of Class of Securities)

78454L100

(CUSIP Number)

DECEMBER 31, 2017

(Date of Event which Requires Filing of this Statement)

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

☐ Rule 13d-1(b)

☒ Rule 13d-1(c)

☐ Rule 13d-1(d)

* 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.

The information required in the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act, but shall be subject to all other provisions of the Act (however, see the Notes).

CUSIP NO. 78454L100

1	Name of Reporting Person: QStar LLC
2	Check the Appropriate Box if a Member of a Group (a)  ☐        (b)  ☐
3	SEC Use Only
4	Citizenship or Place of Organization Delaware
Number of Shares Beneficially Owned by Each Reporting Person With		5	Sole Voting Power 8,187,510
		6	Shared Voting Power 0
		7	Sole Dispositive Power 8,187,510
		8	Shared Dispositive Power 0
9	Aggregate Amount Beneficially Owned by Each Reporting Person 8,187,510
10	Check if the Aggregate Amount in Row (9) Excludes Certain Shares  ☐
11	Percent of Class Represented by Amount in Row (9) 7.3% (1)
12	Type of Reporting Person OO (Limited Liability Company)

(1) Based on 111,624,029 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 26, 2017, as set forth in the Issuer’s Quarterly Report on Form 10-Q for the quarter ended September 30, 2017, filed with the Securities and Exchange Commission (the “SEC”) on November 3, 2017.

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CUSIP NO. 78454L100

1	Name of Reporting Person: EnCap Energy Capital Fund IX, L.P.
2	Check the Appropriate Box if a Member of a Group (a)  ☐        (b)  ☐
3	SEC Use Only
4	Citizenship or Place of Organization Texas
Number of Shares Beneficially Owned by Each Reporting Person With		5	Sole Voting Power 8,187,510
		6	Shared Voting Power 0
		7	Sole Dispositive Power 8,187,510
		8	Shared Dispositive Power 0
9	Aggregate Amount Beneficially Owned by Each Reporting Person 8,187,510 (1)
10	Check if the Aggregate Amount in Row (9) Excludes Certain Shares  ☐
11	Percent of Class Represented by Amount in Row (9) 7.3% (2)
12	Type of Reporting Person OO (Limited Partnership)

(1) Includes 8,187,510 shares of Common Stock owned by 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. As a result, EnCap Fund IX may be deemed to have the 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 and this statement shall not be deemed an admission that EnCap Fund IX 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 (the “Exchange Act”) or any other purpose.

(2) Based on 111,624,029 shares of Common Stock, issued and outstanding as of October 26, 2017, as set forth in the Issuer’s Quarterly Report on Form 10-Q for the quarter ended September 30, 2017, filed with the SEC on November 3, 2017.

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CUSIP NO. 78454L100

1	Name of Reporting Person: EnCap Partners GP, LLC (1)
2	Check the Appropriate Box if a Member of a Group (a)  ☐        (b)  ☐
3	SEC Use Only
4	Citizenship or Place of Organization Delaware
Number of Shares Beneficially Owned by Each Reporting Person With		5	Sole Voting Power 8,187,510
		6	Shared Voting Power 0
		7	Sole Dispositive Power 8,187,510
		8	Shared Dispositive Power 0
9	Aggregate Amount Beneficially Owned by Each Reporting Person 8,187,510 (2)
10	Check if the Aggregate Amount in Row (9) Excludes Certain Shares  ☐
11	Percent of Class Represented by Amount in Row (9) 7.3% (3)
12	Type of Reporting Person OO (Limited Liability Company)

(1) The Schedule 13G previously filed listed EnCap Partners, LLC as a reporting person. Effective April 6, 2017, EnCap Partners, LLC was converted into a limited partnership with the name EnCap Partners, LP (“EnCap Partners”). In connection with the conversion, EnCap Partners GP, LLC (“EnCap Partners GP”) was formed as its sole general partner.

(2) Includes 8,187,510 shares of Common Stock owned by QStar. EnCap Partners GP is the sole general partner of 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. As a result, EnCap Partners GP may be deemed to have the 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 such entity is the beneficial owner of the reported Common Stock for the purposes of Section 13(d) of the Exchange Act or any other purpose.

(3) Based on 111,624,029 shares of Common Stock, issued and outstanding as of October 26, 2017, as set forth in the Issuer’s Quarterly Report on Form 10-Q for the quarter ended September 30, 2017, filed with the SEC on November 3, 2017.

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Item 1(a). Name of issuer:

SM Energy Company (the “Issuer”)

Item 1(b). Address of issuer’s principal executive offices:

1775 Sherman Street, Suite 1200

Denver, Colorado 80203

Item 2(a). Names of persons filing:

This Schedule 13G is being filed jointly by the following persons (the “Reporting Persons”):

(i) QStar LLC, a Delaware limited liability company

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

(iii) EnCap Partners GP, LLC, a Delaware limited liability company

Item 2(b). Address or principal business office or, if none, residence of each Reporting Person is:

1100 Louisiana Street

Suite 4900

Houston, Texas 77002

Item 2(c). Citizenship:

QStar LLC and EnCap Partners GP, LLC are each organized under the laws of the State of Delaware. EnCap Energy Capital Fund IX, L.P. is organized under the laws of the State of Texas.

Item 2(d). Title of class of securities:

Common Stock, par value $0.01 per share, of the Issuer.

Item 2(e). CUSIP number:

78454L100

Item 3. If this statement is filed pursuant to Rule 13d-1(b), or 13d-2(b) or (c), check whether the person filing is a:

Not applicable.

Item 4. Ownership:

The information regarding ownership set forth in Items 5-9 and 11 of each cover page is hereby incorporated herein by reference.

Item 5. Ownership of five percent or less of a class:

Not applicable.

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Item 6. Ownership of more than five percent on behalf of another person:

Not applicable.

Item 7. Identification and classification of the subsidiary which acquired the security being reported on by the parent holding company or control person:

Not applicable.

Item 8. Identification and classification of members of the group:

Not applicable.

Item 9. Notice of dissolution of group:

Not applicable.

Item 10. Certifications:

By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect.

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SIGNATURE

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

Dated: February 5, 2018

QStar LLC
By:	/s/ Joel E. Saber
Name:	Joel E. Saber
Title:	Chief Financial Officer
EnCap Energy Capital Fund IX, L.P.
By:	EnCap Equity Fund IX GP, L.P.,
	General Partner of EnCap Energy Capital Fund IX, L.P.
By:	EnCap Investments L.P.,
	General Partner of EnCap Equity Fund IX GP, L.P.
By:	EnCap Investments GP, L.L.C,
	General Partner of EnCap Investments L.P.
By:	/s/ D. Martin Phillips
Name:	D. Martin Phillips
Title:	Managing Partner
EnCap Partners GP, LLC
By:	/s/ D. Martin Phillips
Name:	D. Martin Phillips
Title:	Managing Partner

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EXHIBIT INDEX

Exhibit No.	Description
1.1	Joint Filing Agreement dated February 5, 2018.

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EX-99.1.1

Exhibit 1.1

JOINT FILING AGREEMENT

In accordance with Rule 13d-1(k)(1) under the Securities Exchange Act of 1934, as amended, the persons named below agree to the joint filing on behalf of each of them of a statement on Schedule 13G (including amendments thereto) with respect to the common stock, par value $0.01 per share, of SM Energy Company, a Delaware corporation, and further agree that this Joint Filing Agreement be included as an exhibit to such joint filings. In evidence thereof, each of the undersigned hereby executes this Joint Filing Agreement as of February 5, 2018.

QStar LLC
By:	/s/ Joel E. Saber
Name:	Joel E. Saber
Title:	Chief Financial Officer
EnCap Energy Capital Fund IX, L.P.
By:	EnCap Equity Fund IX GP, L.P.,
	General Partner of EnCap Energy Capital Fund IX, L.P.
By:	EnCap Investments L.P.,
	General Partner of EnCap Equity Fund IX GP, L.P.
By:	EnCap Investments GP, L.L.C,
	General Partner of EnCap Investments L.P.
By:	/s/ D. Martin Phillips
Name:	D. Martin Phillips
Title:	Managing Partner
EnCap Partners GP, LLC
By:	/s/ D. Martin Phillips
Name:	D. Martin Phillips
Title:	Managing Partner

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