Exhibit 99.1
Joint Filers' Signatures
WARBURG PINCUS PRIVATE EQUITY X O&G, L.P.
By: Warburg Pincus X, L.P., its general partner
By: Warburg Pincus X GP L.P., its general partner
By: WPP GP LLC, its general partner
By: Warburg Pincus Partners, L.P., its managing member
By: Warburg Pincus Partners GP LLC, its general partner
By: Warburg Pincus & Co., its managing member
By: /s/ Robert B. Knauss Date: March 14, 2019
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Name: Robert B. Knauss
Title: Partner
WARBURG PINCUS X, L.P.
By: Warburg Pincus X GP L.P., its general partner
By: WPP GP LLC, its general partner
By: Warburg Pincus Partners, L.P., its managing member
By: Warburg Pincus Partners GP LLC, its general partner
By: Warburg Pincus & Co., its managing member
By: /s/ Robert B. Knauss Date: March 14, 2019
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Name: Robert B. Knauss
Title: Partner
WARBURG PINCUS X GP L.P.
By: WPP GP LLC, its general partner
By: Warburg Pincus Partners, L.P., its managing member
By: Warburg Pincus Partners GP LLC, its general partner
By: Warburg Pincus & Co., its managing member
By: /s/ Robert B. Knauss Date: March 14, 2019
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Name: Robert B. Knauss
Title: Partner
WPP GP LLC
By: Warburg Pincus Partners, L.P., its managing member
By: Warburg Pincus Partners GP LLC, its general partner
By: Warburg Pincus & Co., its managing member
By: /s/ Robert B. Knauss Date: March 14, 2019
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Name: Robert B. Knauss
Title: Partner
WARBURG PINCUS PARTNERS, L.P.
By: Warburg Pincus Partners GP LLC, its general partner
By: Warburg Pincus & Co., its managing member
By: /s/ Robert B. Knauss Date: March 14, 2019
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Name: Robert B. Knauss
Title: Partner
WARBURG PINCUS PARTNERS GP LLC
By: Warburg Pincus & Co., its managing member
By: /s/ Robert B. Knauss Date: March 14, 2019
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Name: Robert B. Knauss
Title: Partner
WARBURG PINCUS & CO.
By: /s/ Robert B. Knauss Date: March 14, 2019
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Name: Robert B. Knauss
Title: Partner
WARBURG PINCUS LLC
By: /s/ Robert B. Knauss Date: March 14, 2019
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Name: Robert B. Knauss
Title: Managing Director
CHARLES R. KAYE
By: /s/ Robert B. Knauss Date: March 14, 2019
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Name: Charles R. Kaye
By: Robert B. Knauss, Attorney-in-Fact*
JOSEPH P. LANDY
By: /s/ Robert B. Knauss Date: March 14, 2019
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Name: Joseph P. Landy
By: Robert B. Knauss, Attorney-in-Fact*
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* The Power of Attorney given by each of Mr. Kaye and Mr. Landy was previously
filed with the U.S. Securities & Exchange Commission on July 12, 2016 as an
exhibit to the statement on Schedule 13D filed by Warburg Pincus LLC with
respect to WEX Inc. and is hereby incorporated by reference.
