SEC Form 4

FORM 4		UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940	OMB APPROVAL OMB Number: 3235-0287 Estimated average burden hours per response: 0.5
	Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

1. Name and Address of Reporting Person* SUMMIT MIDSTREAM PARTNERS HOLDINGS, LLC (Last) (First) (Middle) C/O SUMMIT MIDSTREAM PARTNERS LP 2100 MCKINNEY AVENUE, SUITE 1250 (Street) DALLAS TX 75201 (City) (State) (Zip)	2. Issuer Name and Ticker or Trading Symbol Summit Midstream Partners, LP [ SMLP ]	5. Relationship of Reporting Person(s) to Issuer (Check all applicable) X Director X 10% Owner Officer (give title below) Other (specify below) SEE REMARKS
	3. Date of Earliest Transaction (Month/Day/Year) 03/17/2014
	4. If Amendment, Date of Original Filed (Month/Day/Year)	6. Individual or Joint/Group Filing (Check Applicable Line) Form filed by One Reporting Person X Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
COMMON UNITS (LIMITED PARTNER INTERESTS)	03/17/2014		S		5,050,000	D	$37.4325(1)	9,641,397	D

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

1. Name and Address of Reporting Person* SUMMIT MIDSTREAM PARTNERS HOLDINGS, LLC (Last) (First) (Middle) C/O SUMMIT MIDSTREAM PARTNERS LP 2100 MCKINNEY AVENUE, SUITE 1250 (Street) DALLAS TX 75201 (City) (State) (Zip)

1. Name and Address of Reporting Person* SUMMIT MIDSTREAM PARTNERS, LLC (Last) (First) (Middle) 2100 MCKINNEY AVENUE, SUITE 1250 (Street) DALLAS TX 75201 (City) (State) (Zip)

1. Name and Address of Reporting Person* SUMMIT MIDSTREAM GP, LLC (Last) (First) (Middle) C/O SUMMIT MIDSTREAM PARTNERS, LLC 2100 MCKINNEY AVENUE, SUITE 1250 (Street) DALLAS TX 75201 (City) (State) (Zip)

1. Name and Address of Reporting Person* ENERGY CAPITAL PARTNERS II, LLC (Last) (First) (Middle) 51 JOHN F. KENNEDY PARKWAY, SUITE 200 (Street) SHORT HILLS NJ 07078 (City) (State) (Zip)

1. Name and Address of Reporting Person* ENERGY CAPITAL PARTNERS II, LP (Last) (First) (Middle) 51 JOHN F. KENNEDY PARKWAY, SUITE 200 (Street) SHORT HILLS NJ 07078 (City) (State) (Zip)

1. Name and Address of Reporting Person* ENERGY CAPITAL PARTNERS II-A, LP (Last) (First) (Middle) 51 JOHN F. KENNEDY PARKWAY, SUITE 200 (Street) SHORT HILLS NJ 07078 (City) (State) (Zip)

1. Name and Address of Reporting Person* ENERGY CAPITAL PARTNERS II-B IP, LP (Last) (First) (Middle) 51 JOHN F. KENNEDY PARKWAY, SUITE 200 (Street) SHORT HILLS NJ 07078 (City) (State) (Zip)

1. Name and Address of Reporting Person* ENERGY CAPITAL PARTNERS II-C (SUMMIT IP), LP (Last) (First) (Middle) 51 JOHN F. KENNEDY PARKWAY, SUITE 200 (Street) SHORT HILLS NJ 07078 (City) (State) (Zip)

1. Name and Address of Reporting Person* Energy Capital Partners II (Summit Co-Invest), LP (Last) (First) (Middle) 51 JOHN F. KENNEDY PARKWAY, SUITE 200 (Street) SHORT HILLS NJ 07078 (City) (State) (Zip)

Explanation of Responses:

1. On March 17, 2014, (a) the Issuer sold 5,300,000 common units representing limited partner interests in the Issuer ("Common Units") and Summit Midstream Partners Holdings, LLC ("SMPH") sold 5,050,000 Common Units, including 1,350,000 Common Units sold pursuant to the underwriters option to purchase additional Common Units, in a public underwritten offering; and (b) the general partner of the Issuer, of which SMPH is the sole owner, purchased 109,198 general partner units to maintain its 2.0% general partner interest in the Issuer.

Remarks:

Energy Capital Partners II, LLC ("ECP"), Energy Capital Partners II, LP ("ECP II"), Energy Capital Partners II-A, LP ("ECP II-A"), Energy Capital Partners II-B IP, LP ("ECP II-B"), Energy Capital Partners II-C (Summit IP), LP ("ECP II-C"), Energy Capital Partners II (Summit Co-Invest), LP ("ECP Summit Co-Invest" and together with ECP II, ECP II-A, ECP II-B and ECP II-C, the "ECP Funds"), collectively hold greater than a majority of the membership interest in Summit Midstream Partners, LLC ("Summit ") and are entitled to elect four of the five directors of Summit. Summit is the sole member of SMPH and as such, may be deemed to have indirect beneficial ownership of the common and subordinated units reported herein. Accordingly, ECP and the ECP Funds may be deemed to indirectly beneficially own the common units and subordinated units held by SMPH but disclaim beneficial ownership except to the extent of their pecuniary interest therein.

	/s/ Brock M. Degeyter, Senior Vice President, General Counsel and Secretary, Summit Midstream Partners Holdings, LLC	03/19/2014
	/s/ Steven J. Newby, President and Chief Executive Officer, Summit Midstream Partners, LLC	03/19/2014
	/s/ Steven J. Newby, President and Chief Executive Officer, Summit Midstream GP, LLC	03/19/2014
	Energy Capital Partners II, LP; By: Energy Capital Partners GP II, LP, its General Partner; By: Energy Capital Partners II, LLC, its General Partner; By: /s/ Christopher M. Leininger, Deputy General Counsel	03/19/2014
	Energy Capital Partners II-A, LP; By: Energy Capital Partners GP II, LP, its General Partner; By: Energy Capital Partners II, LLC, its General Partner; By: /s/ Christopher M. Leininger, Deputy General Counsel	03/19/2014
	Energy Capital Partners II-B IP, LP; By: Energy Capital Partners GP II, LP, its General Partner; By: Energy Capital Partners II, LLC, its General Partner; By: /s/ Christopher M. Leininger, Deputy General Counsel	03/19/2014
	Energy Capital Partners II-C (Summit IP), LP; By: Energy Capital Partners GP II, LP, its General Partner; By: Energy Capital Partners II, LLC, its General Partner; By: /s/ Christopher M. Leininger, Deputy General Counsel	03/19/2014
	Energy Capital Partners II (Summit Co-Invest), LP; By: Energy Capital Partners GP II Co-Investment (Summit), LLC, its General Partner; By: Energy Capital Partners II, LLC, its Managing Member; By: /s/ Christopher M. Leininger, Deputy General Counsel	03/19/2014
	/s/ Christopher M. Leininger, Deputy General Counsel, Energy Capital Partners II, LLC	03/19/2014
	** Signature of Reporting Person	Date
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