<SEC-DOCUMENT>0001104659-17-020373.txt : 20170330
<SEC-HEADER>0001104659-17-020373.hdr.sgml : 20170330
<ACCEPTANCE-DATETIME>20170330161659
ACCESSION NUMBER:		0001104659-17-020373
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20170328
FILED AS OF DATE:		20170330
DATE AS OF CHANGE:		20170330

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			ProPetro Holding Corp.
		CENTRAL INDEX KEY:			0001680247
		STANDARD INDUSTRIAL CLASSIFICATION:	OIL, GAS FIELD SERVICES, NBC [1389]
		IRS NUMBER:				263685382
		STATE OF INCORPORATION:			TX
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		1706 S. MIDKIFF ROAD, BUILDING B
		CITY:			MIDLAND
		STATE:			TX
		ZIP:			79701
		BUSINESS PHONE:		(432) 688-0012

	MAIL ADDRESS:	
		STREET 1:		1706 S. MIDKIFF ROAD, BUILDING B
		CITY:			MIDLAND
		STATE:			TX
		ZIP:			79701

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Energy Capital Partners GP II, LP
		CENTRAL INDEX KEY:			0001700831
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-38035
		FILM NUMBER:		17725881

	BUSINESS ADDRESS:	
		STREET 1:		51 JOHN F. KENNEDY PARKWAY, SUITE 200
		CITY:			SHORT HILLS
		STATE:			NJ
		ZIP:			07078
		BUSINESS PHONE:		973-671-6100

	MAIL ADDRESS:	
		STREET 1:		51 JOHN F. KENNEDY PARKWAY, SUITE 200
		CITY:			SHORT HILLS
		STATE:			NJ
		ZIP:			07078

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Energy Capital Partners GP II Co-Investment (Midland), LLC
		CENTRAL INDEX KEY:			0001700832
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-38035
		FILM NUMBER:		17725882

	BUSINESS ADDRESS:	
		STREET 1:		51 JOHN F. KENNEDY PARKWAY, SUITE 200
		CITY:			SHORT HILLS
		STATE:			NJ
		ZIP:			07078
		BUSINESS PHONE:		973-671-6100

	MAIL ADDRESS:	
		STREET 1:		51 JOHN F. KENNEDY PARKWAY, SUITE 200
		CITY:			SHORT HILLS
		STATE:			NJ
		ZIP:			07078

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			ENERGY CAPITAL PARTNERS II-D, LP
		CENTRAL INDEX KEY:			0001483784
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-38035
		FILM NUMBER:		17725884

	BUSINESS ADDRESS:	
		STREET 1:		51 JOHN F. KENNEDY PARKWAY
		STREET 2:		SUITE 200
		CITY:			SHORT HILLS
		STATE:			NJ
		ZIP:			07078
		BUSINESS PHONE:		973-671-6100

	MAIL ADDRESS:	
		STREET 1:		51 JOHN F. KENNEDY PARKWAY
		STREET 2:		SUITE 200
		CITY:			SHORT HILLS
		STATE:			NJ
		ZIP:			07078

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			ENERGY CAPITAL PARTNERS II-A, LP
		CENTRAL INDEX KEY:			0001456364
		STATE OF INCORPORATION:			DE

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-38035
		FILM NUMBER:		17725887

	BUSINESS ADDRESS:	
		STREET 1:		51 JOHN F KENNEDYPARKWAY
		STREET 2:		SUITE 200
		CITY:			SHORT HILLS
		STATE:			NJ
		ZIP:			07078
		BUSINESS PHONE:		973-671-6100

	MAIL ADDRESS:	
		STREET 1:		51 JOHN F KENNEDYPARKWAY
		STREET 2:		SUITE 200
		CITY:			SHORT HILLS
		STATE:			NJ
		ZIP:			07078

	FORMER NAME:	
		FORMER CONFORMED NAME:	ENERGY CAPITAL PARTNERS II-A LP
		DATE OF NAME CHANGE:	20090213

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			ENERGY CAPITAL PARTNERS II, LP
		CENTRAL INDEX KEY:			0001456360
		STATE OF INCORPORATION:			DE

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-38035
		FILM NUMBER:		17725888

	BUSINESS ADDRESS:	
		STREET 1:		51 JOHN F KENNEDY PARKWAY
		STREET 2:		SUITE 200
		CITY:			SHORT HILLS
		STATE:			NJ
		ZIP:			07078
		BUSINESS PHONE:		973-671-6100

	MAIL ADDRESS:	
		STREET 1:		51 JOHN F KENNEDY PARKWAY
		STREET 2:		SUITE 200
		CITY:			SHORT HILLS
		STATE:			NJ
		ZIP:			07078

	FORMER NAME:	
		FORMER CONFORMED NAME:	ENERGY CAPITAL PARTNERS II LP
		DATE OF NAME CHANGE:	20090213

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			ENERGY CAPITAL PARTNERS II-B, LP
		CENTRAL INDEX KEY:			0001456359
		STATE OF INCORPORATION:			DE

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-38035
		FILM NUMBER:		17725886

	BUSINESS ADDRESS:	
		STREET 1:		51 JOHN F KENNEDY PARKWAY
		STREET 2:		SUITE 200
		CITY:			SHORT HILLS
		STATE:			NJ
		ZIP:			07078
		BUSINESS PHONE:		973-671-6100

	MAIL ADDRESS:	
		STREET 1:		51 JOHN F KENNEDY PARKWAY
		STREET 2:		SUITE 200
		CITY:			SHORT HILLS
		STATE:			NJ
		ZIP:			07078

	FORMER NAME:	
		FORMER CONFORMED NAME:	ENERGY CAPITAL PARTNERS II B LP
		DATE OF NAME CHANGE:	20090213

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Energy Capital Partners II (Midland Co-Invest), LP
		CENTRAL INDEX KEY:			0001575667
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-38035
		FILM NUMBER:		17725883

	BUSINESS ADDRESS:	
		STREET 1:		C/O ENERGY CAPITAL PARTNERS II, LLC
		STREET 2:		51 JOHN F. KENNEDY PKWY, SUITE 200
		CITY:			SHORT HILLS
		STATE:			NJ
		ZIP:			07078
		BUSINESS PHONE:		(973) 671-6108

	MAIL ADDRESS:	
		STREET 1:		C/O ENERGY CAPITAL PARTNERS II, LLC
		STREET 2:		51 JOHN F. KENNEDY PKWY, SUITE 200
		CITY:			SHORT HILLS
		STATE:			NJ
		ZIP:			07078

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			ENERGY CAPITAL PARTNERS II, LLC
		CENTRAL INDEX KEY:			0001558915
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-38035
		FILM NUMBER:		17725889

	BUSINESS ADDRESS:	
		STREET 1:		51 JOHN F. KENNEDY PARKWAY, SUITE 1250
		CITY:			SHORT HILLS
		STATE:			NJ
		ZIP:			07078
		BUSINESS PHONE:		(973) 671-6100

	MAIL ADDRESS:	
		STREET 1:		51 JOHN F. KENNEDY PARKWAY, SUITE 1250
		CITY:			SHORT HILLS
		STATE:			NJ
		ZIP:			07078

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Energy Capital Partners II-C (Direct IP), LP
		CENTRAL INDEX KEY:			0001700624
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-38035
		FILM NUMBER:		17725885

	BUSINESS ADDRESS:	
		STREET 1:		51 JOHN F. KENNEDY PARKWAY, SUITE 200
		CITY:			SHORT HILLS
		STATE:			NJ
		ZIP:			07078
		BUSINESS PHONE:		973-671-6100

	MAIL ADDRESS:	
		STREET 1:		51 JOHN F. KENNEDY PARKWAY, SUITE 200
		CITY:			SHORT HILLS
		STATE:			NJ
		ZIP:			07078
</SEC-HEADER>
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<SEQUENCE>1
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    <periodOfReport>2017-03-28</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001680247</issuerCik>
        <issuerName>ProPetro Holding Corp.</issuerName>
        <issuerTradingSymbol>PUMP</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001558915</rptOwnerCik>
            <rptOwnerName>ENERGY CAPITAL PARTNERS II, LLC</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>51 JOHN F. KENNEDY PARKWAY</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 200</rptOwnerStreet2>
            <rptOwnerCity>SHORT HILLS</rptOwnerCity>
            <rptOwnerState>NJ</rptOwnerState>
            <rptOwnerZipCode>07078</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
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            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001456360</rptOwnerCik>
            <rptOwnerName>ENERGY CAPITAL PARTNERS II, LP</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>51 JOHN F. KENNEDY PARKWAY</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 200</rptOwnerStreet2>
            <rptOwnerCity>SHORT HILLS</rptOwnerCity>
            <rptOwnerState>NJ</rptOwnerState>
            <rptOwnerZipCode>07078</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
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            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001456364</rptOwnerCik>
            <rptOwnerName>ENERGY CAPITAL PARTNERS II-A, LP</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>51 JOHN F. KENNEDY PARKWAY</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 200</rptOwnerStreet2>
            <rptOwnerCity>SHORT HILLS</rptOwnerCity>
            <rptOwnerState>NJ</rptOwnerState>
            <rptOwnerZipCode>07078</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
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            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001456359</rptOwnerCik>
            <rptOwnerName>ENERGY CAPITAL PARTNERS II-B, LP</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>51 JOHN F. KENNEDY PARKWAY</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 200</rptOwnerStreet2>
            <rptOwnerCity>SHORT HILLS</rptOwnerCity>
            <rptOwnerState>NJ</rptOwnerState>
            <rptOwnerZipCode>07078</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001700624</rptOwnerCik>
            <rptOwnerName>Energy Capital Partners II-C (Direct IP), LP</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>51 JOHN F. KENNEDY PARKWAY</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 200</rptOwnerStreet2>
            <rptOwnerCity>SHORT HILLS</rptOwnerCity>
            <rptOwnerState>NJ</rptOwnerState>
            <rptOwnerZipCode>07078</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001483784</rptOwnerCik>
            <rptOwnerName>ENERGY CAPITAL PARTNERS II-D, LP</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>51 JOHN F. KENNEDY PARKWAY</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 200</rptOwnerStreet2>
            <rptOwnerCity>SHORT HILLS</rptOwnerCity>
            <rptOwnerState>NJ</rptOwnerState>
            <rptOwnerZipCode>07078</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001575667</rptOwnerCik>
            <rptOwnerName>Energy Capital Partners II (Midland Co-Invest), LP</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>51 JOHN F. KENNEDY PARKWAY</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 200</rptOwnerStreet2>
            <rptOwnerCity>SHORT HILLS</rptOwnerCity>
            <rptOwnerState>NJ</rptOwnerState>
            <rptOwnerZipCode>07078</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001700832</rptOwnerCik>
            <rptOwnerName>Energy Capital Partners GP II Co-Investment (Midland), LLC</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>51 JOHN F. KENNEDY PARKWAY</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 200</rptOwnerStreet2>
            <rptOwnerCity>SHORT HILLS</rptOwnerCity>
            <rptOwnerState>NJ</rptOwnerState>
            <rptOwnerZipCode>07078</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001700831</rptOwnerCik>
            <rptOwnerName>Energy Capital Partners GP II, LP</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>51 JOHN F. KENNEDY PARKWAY</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 200</rptOwnerStreet2>
            <rptOwnerCity>SHORT HILLS</rptOwnerCity>
            <rptOwnerState>NJ</rptOwnerState>
            <rptOwnerZipCode>07078</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2017-03-28</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>2771557</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>14.00</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>34527928</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See footnote</value>
                    <footnoteId id="F1"/>
                    <footnoteId id="F2"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Following the transaction reported herein, includes (i) 517,092 shares held by Energy Capital Partners II, LP (&quot;ECP II&quot;), (ii) 16,843,582 shares held by Energy Capital Partners II-A, LP (&quot;ECP II-A&quot;), (iii) 3,526,945 shares held by Energy Capital Partners II-B, LP (&quot;ECP II-B&quot;), (iv) 6,195,410 shares held by Energy Capital Partners II-C (Direct IP), LP (&quot;ECP II-C&quot;), (v) 4,151,258 shares held by Energy Capital Partners II-D, LP (&quot;ECP II-D&quot;), and (vi) 3,293,641 shares held by Energy Capital Partners II (Midland Co-Invest), LP (&quot;ECP Co-Invest&quot;). Each of ECP II, ECP II-A, ECP II-B, ECP II-C and ECP II-D is managed by its general partner, Energy Capital Partners GP II, LP. Energy Capital Partners GP II, LP is managed by its general partner, Energy Capital Partners II, LLC (&quot;Energy Capital Partners&quot;). ECP Co-Invest is managed by its general partner, Energy Capital Partners GP II Co-Investment (Midland), LLC, which is managed by its sole member, Energy Capital Partners.</footnote>
        <footnote id="F2">As a result, each of Energy Capital Partners GP II, LP and Energy Capital Partners may be deemed to share beneficial ownership of the shares held by ECP II, ECP II-A, ECP II-B, ECP II-C and ECP II-D, and each of Energy Capital Partners GP II Co-Investment (Midland), LLC and Energy Capital Partners may be deemed to share beneficial ownership of the shares held by ECP Co-Invest. Douglas W. Kimmelman, Peter Labbat, Thomas K. Lane, Tyler Reeder and Andrew D. Singer are the managing members of, and Rahman D'Argenio is a partner of, Energy Capital Partners and share the power to direct the voting and disposition of the shares beneficially owned by Energy Capital Partners. Each such individual disclaims beneficial ownership of such shares except to the extent of their pecuniary interest therein.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Energy Capital Partners II, LLC By: /s/ Christopher M. Leininger, Managing Director and Deputy General Counsel</signatureName>
        <signatureDate>2017-03-30</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>Energy Capital Partners GP II, LP By: Energy Capital Partners II, LLC, its general partner By: /s/ Christopher M. Leininger, Managing Director and Deputy General Counsel</signatureName>
        <signatureDate>2017-03-30</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>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, Managing Director and Deputy General Counsel</signatureName>
        <signatureDate>2017-03-30</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>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, Managing Director and Deputy General Counsel</signatureName>
        <signatureDate>2017-03-30</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>Energy Capital Partners II-B, 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, Managing Director and Deputy General Counsel</signatureName>
        <signatureDate>2017-03-30</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>Energy Capital Partners II-C (Direct 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, Managing Director and Deputy General Counsel</signatureName>
        <signatureDate>2017-03-30</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>Energy Capital Partners II-D, 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, Managing Director and Deputy General Counsel</signatureName>
        <signatureDate>2017-03-30</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>Energy Capital Partners II (Midland Co-Invest), LP By: Energy Capital Partners GP II Co-Investment (Midland), LLC, its GP By: Energy Capital Partners II, LLC, its sole member By: /s/ Christopher M. Leininger, Managing Director and Deputy General Counsel</signatureName>
        <signatureDate>2017-03-30</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>Energy Capital Partners GP II Co-Investment (Midland), LLC By: Energy Capital Partners II, LLC, its sole member By: /s/ Christopher M. Leininger, Managing Director and Deputy  General Counsel</signatureName>
        <signatureDate>2017-03-30</signatureDate>
    </ownerSignature>
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