SMC

SEC source: 0002024218-26-000032 · wk-form4_1773791169.xml · nonDerivative · entry 6

Johnston James David · CIK 0001823482 · Executive VP, GC, CCO and Secy

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 77,957

F2 · shares: Common stocks being withheld to pay tax liability.

SEC source: 0002024218-26-000032 · wk-form4_1773791169.xml · nonDerivative · entry 5

Johnston James David · CIK 0001823482 · Executive VP, GC, CCO and Secy

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 81,811

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · price: Each corporation restricted stock unit is the economic equivalent of one common stock.

SEC source: 0002024218-26-000032 · wk-form4_1773791169.xml · nonDerivative · entry 4

Johnston James David · CIK 0001823482 · Executive VP, GC, CCO and Secy

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 72,018

F2 · shares: Common stocks being withheld to pay tax liability.

SEC source: 0002024218-26-000032 · wk-form4_1773791169.xml · nonDerivative · entry 3

Johnston James David · CIK 0001823482 · Executive VP, GC, CCO and Secy

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 73,849

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · price: Each corporation restricted stock unit is the economic equivalent of one common stock.

SEC source: 0002024218-26-000032 · wk-form4_1773791169.xml · nonDerivative · entry 2

Johnston James David · CIK 0001823482 · Executive VP, GC, CCO and Secy

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 69,196

F2 · shares: Common stocks being withheld to pay tax liability.

SEC source: 0002024218-26-000032 · wk-form4_1773791169.xml · nonDerivative · entry 1

Johnston James David · CIK 0001823482 · Executive VP, GC, CCO and Secy

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 76,664

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · price: Each corporation restricted stock unit is the economic equivalent of one common stock.

SEC source: 0002024218-26-000009 · wk-form4_1769039783.xml · derivative · entry 3

Mault William J. · CIK 0001911803 · Executive VP and CFO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 84,746

Underlying: Common Stock · 10,121 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_price: Each corporation restricted stock unit is the economic equivalent of one common stock.

F3 · derivative.exercise_date: One-third of the corporation restricted stock units subject to the original award agreement vested on January 16, 2026, with the remaining corporation restricted stock units subject to vesting on the third anniversary of the January 18, 2024 reference date, subject to continued employment. The Reporting Person received distribution equivalent rights ("DERs") for each corporation restricted stock unit, providing for payment on the vesting date of a lump sum of cash equal to the accrued distributions from and after the grant date of the corporation restricted stock units.

F4 · derivative.expiration_date: The corporation restricted stock units and associated DERs do not expire. The corporation restricted stock units are settled upon vesting in common stocks (on a one-for-one basis) or in cash, at the discretion of the Issuer.

F5 · balance_after: This total includes corporation restricted stock units from other tranches with different vesting dates.

SEC source: 0002024218-26-000009 · wk-form4_1769039783.xml · nonDerivative · entry 2

Mault William J. · CIK 0001911803 · Executive VP and CFO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 70,588

F2 · shares: Common stocks being withheld to pay tax liability.

SEC source: 0002024218-26-000009 · wk-form4_1769039783.xml · nonDerivative · entry 1

Mault William J. · CIK 0001911803 · Executive VP and CFO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 73,345

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · price: Each corporation restricted stock unit is the economic equivalent of one common stock.

SEC source: 0002024218-26-000008 · wk-form4_1769039708.xml · derivative · entry 3

Sicinski Matthew B. · CIK 0001911802 · Senior VP and CAO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 29,362

Underlying: Common Stock · 3,593 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_price: Each corporation restricted stock unit is the economic equivalent of one common stock.

F3 · derivative.exercise_date: One-third of the corporation restricted stock units subject to the original award agreement vested on January 16, 2026, with the remaining corporation restricted stock units subject to vesting on the third anniversary of the January 18, 2024 reference date, subject to continued employment. The Reporting Person received distribution equivalent rights ("DERs") for each corporation restricted stock unit, providing for payment on the vesting date of a lump sum of cash equal to the accrued distributions from and after the grant date of the corporation restricted stock units.

F4 · derivative.expiration_date: The corporation restricted stock units and associated DERs do not expire. The corporation restricted stock units are settled upon vesting in common stocks (on a one-for-one basis) or in cash, at the discretion of the Issuer.

F5 · balance_after: This total includes corporation restricted stock units from other tranches with different vesting dates.

SEC source: 0002024218-26-000008 · wk-form4_1769039708.xml · nonDerivative · entry 2

Sicinski Matthew B. · CIK 0001911802 · Senior VP and CAO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 31,347

F2 · shares: Common stocks being withheld to pay tax liability.

SEC source: 0002024218-26-000008 · wk-form4_1769039708.xml · nonDerivative · entry 1

Sicinski Matthew B. · CIK 0001911802 · Senior VP and CAO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 32,413

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · price: Each corporation restricted stock unit is the economic equivalent of one common stock.

SEC source: 0002024218-26-000007 · wk-form4_1769039610.xml · derivative · entry 3

Johnston James David · CIK 0001823482 · Executive VP, GC, CCO and Secy

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 89,717

Underlying: Common Stock · 10,794 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_price: Each corporation restricted stock unit is the economic equivalent of one common stock.

F3 · derivative.exercise_date: One-third of the corporation restricted stock units subject to the original award agreement vested on January 16, 2026, with the remaining corporation restricted stock units subject to vesting on the third anniversary of the January 18, 2024 reference date, subject to continued employment. The Reporting Person received distribution equivalent rights ("DERs") for each corporation restricted stock unit, providing for payment on the vesting date of a lump sum of cash equal to the accrued distributions from and after the grant date of the corporation restricted stock units.

F4 · derivative.expiration_date: The corporation restricted stock units and associated DERs do not expire. The corporation restricted stock units are settled upon vesting in common stocks (on a one-for-one basis) or in cash, at the discretion of the Issuer.

F5 · balance_after: This total includes corporation restricted stock units from other tranches with different vesting dates.

SEC source: 0002024218-26-000007 · wk-form4_1769039610.xml · nonDerivative · entry 2

Johnston James David · CIK 0001823482 · Executive VP, GC, CCO and Secy

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 57,687

F2 · shares: Common stocks being withheld to pay tax liability.

SEC source: 0002024218-26-000007 · wk-form4_1769039610.xml · nonDerivative · entry 1

Johnston James David · CIK 0001823482 · Executive VP, GC, CCO and Secy

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 60,610

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · price: Each corporation restricted stock unit is the economic equivalent of one common stock.

SEC source: 0002024218-26-000003 · wk-form4_1769037567.xml · derivative · entry 3

Deneke J Heath · CIK 0001555671 · Chairman, President and CEO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 283,556

Underlying: Common Stock · 32,754 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_price: Each corporation restricted stock unit is the economic equivalent of one common stock.

F3 · derivative.exercise_date: One-third of the corporation restricted stock units subject to the original award agreement vested on January 16, 2026, with the remaining corporation restricted stock units subject to vesting on the third anniversary of the January 18, 2024 reference date, subject to continued employment. The Reporting Person received distribution equivalent rights ("DERs") for each corporation restricted stock unit, providing for payment on the vesting date of a lump sum of cash equal to the accrued distributions from and after the grant date of the corporation restricted stock units.

F4 · derivative.expiration_date: The corporation restricted stock units and associated DERs do not expire. The corporation restricted stock units are settled upon vesting in common stocks (on a one-for-one basis) or in cash, at the discretion of the Issuer.

F5 · balance_after: This total includes corporation restricted stock units from other tranches with different vesting dates.

SEC source: 0002024218-26-000003 · wk-form4_1769037567.xml · nonDerivative · entry 2

Deneke J Heath · CIK 0001555671 · Chairman, President and CEO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 290,708

F2 · shares: Common stocks being withheld to pay tax liability.

SEC source: 0002024218-26-000003 · wk-form4_1769037567.xml · nonDerivative · entry 1

Deneke J Heath · CIK 0001555671 · Chairman, President and CEO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 298,924

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · price: Each corporation restricted stock unit is the economic equivalent of one common stock.

SEC source: 0001213900-25-083560 · ownership.xml · nonDerivative · entry 1

Connect Midstream, LLC · CIK 0002045908 · 10% owner

Tailwater Energy Fund III LP · CIK 0001710146 · 10% owner

Tailwater Capital LLC · CIK 0001615830 · 10% owner

Downie Jason H · CIK 0001351303 · Director · 10% owner

Herring Edward · CIK 0001483120 · Director · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 146,479

F1 · price: The price reported is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $20.43 to $21.01. The Reporting Person undertakes to provide to Summit Midstream Corp (the "Issuer"), any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the ranges set forth in this footnote.

F1 · balance_after: The price reported is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $20.43 to $21.01. The Reporting Person undertakes to provide to Summit Midstream Corp (the "Issuer"), any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the ranges set forth in this footnote.

F2 · ownership.direct: The reported securities are held directly by Connect Midstream, LLC. Tailwater Energy Fund III LP is the sole member of Connect Midstream, LLC. TW GP EF-III LP is the general partner of Tailwater Energy Fund III LP. TW GP EF-III GP, LLC is the general partner of TW GP EF-III LP. Tailwater Capital LLC is the sole member of TW GP EF-III GP, LLC. Jason Downie and Edward Herring are each a Managing Partner of Tailwater Capital LLC. Each of the foregoing disclaim beneficial ownership of the reported securities directly held by Connect Midstream, LLC except to the extent of their respective pecuniary interest therein.

SEC source: 0001213900-25-082006 · ownership.xml · nonDerivative · entry 2

Connect Midstream, LLC · CIK 0002045908 · 10% owner

Tailwater Energy Fund III LP · CIK 0001710146 · 10% owner

Tailwater Capital LLC · CIK 0001615830 · 10% owner

Downie Jason H · CIK 0001351303 · Director · 10% owner

Herring Edward · CIK 0001483120 · Director · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 120,160

F2 · price: The price reported is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $20.35 to $20.82. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the ranges set forth in this footnote.

F2 · balance_after: The price reported is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $20.35 to $20.82. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the ranges set forth in this footnote.

F3 · ownership.direct: The reported securities are held directly by Connect Midstream, LLC. Tailwater Energy Fund III LP is the sole member of Connect Midstream, LLC. TW GP EF-III LP is the general partner of Tailwater Energy Fund III LP. TW GP EF-III GP, LLC is the general partner of TW GP EF-III LP. Tailwater Capital LLC is the sole member of TW GP EF-III GP, LLC. Jason Downie and Edward Herring are each a Managing Partner of Tailwater Capital LLC. Each of the foregoing disclaim beneficial ownership of the reported securities directly held by Connect Midstream, LLC except to the extent of their respective pecuniary interest therein.

SEC source: 0001213900-25-082006 · ownership.xml · nonDerivative · entry 1

Connect Midstream, LLC · CIK 0002045908 · 10% owner

Tailwater Energy Fund III LP · CIK 0001710146 · 10% owner

Tailwater Capital LLC · CIK 0001615830 · 10% owner

Downie Jason H · CIK 0001351303 · Director · 10% owner

Herring Edward · CIK 0001483120 · Director · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 72,759

F1 · price: The price reported is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $19.87 to $20.75. The Reporting Person undertakes to provide to Summit Midstream Corp (the "Issuer"), any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the ranges set forth in this footnote.

F1 · balance_after: The price reported is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $19.87 to $20.75. The Reporting Person undertakes to provide to Summit Midstream Corp (the "Issuer"), any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the ranges set forth in this footnote.

F3 · ownership.direct: The reported securities are held directly by Connect Midstream, LLC. Tailwater Energy Fund III LP is the sole member of Connect Midstream, LLC. TW GP EF-III LP is the general partner of Tailwater Energy Fund III LP. TW GP EF-III GP, LLC is the general partner of TW GP EF-III LP. Tailwater Capital LLC is the sole member of TW GP EF-III GP, LLC. Jason Downie and Edward Herring are each a Managing Partner of Tailwater Capital LLC. Each of the foregoing disclaim beneficial ownership of the reported securities directly held by Connect Midstream, LLC except to the extent of their respective pecuniary interest therein.

SEC source: 0002024218-25-000045 · wk-form4_1745880694.xml · nonDerivative · entry 1

PETERS JERRY L · CIK 0001237636 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

F1 · balance_after: After giving effect to the transfer in this Report, the Reporting Person directly holds an aggregate of 0 common stocks and indirectly owns 23,246 common units under the Joint Spousal Trust of which the Reporting Person is a trustee. The Reporting Person and his spouse are the sole beneficiaries of the Joint Spousal Trust.

SEC source: 0002024218-25-000042 · wk-form4_1743195496.xml · nonDerivative · entry 3

Deneke J Heath · CIK 0001555671 · Chairman, President and CEO

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 266,170

F1 · kind: These Common Stocks were sold in compliance with a qualified selling plan adopted by the reporting person pursuant to Rule 10b5-1 under the Securities Exchange Act of 1934, as amended.

SEC source: 0002024218-25-000042 · wk-form4_1743195496.xml · nonDerivative · entry 2

Deneke J Heath · CIK 0001555671 · Chairman, President and CEO

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 266,220

F1 · kind: These Common Stocks were sold in compliance with a qualified selling plan adopted by the reporting person pursuant to Rule 10b5-1 under the Securities Exchange Act of 1934, as amended.

F3 · price: The price reported in Column 4 is a weighted average price and has been rounded to the nearest cent. These Common Stocks were sold in multiple transactions at prices ranging from $35.52 to $35.96, inclusive. The reporting person undertakes to provide to Summit Midstream Corporation, any security holder of Summit Midstream Corporation, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of Common Stocks sold at each separate price within the ranges set forth in footnote 3 to this Form 4.

SEC source: 0002024218-25-000042 · wk-form4_1743195496.xml · nonDerivative · entry 1

Deneke J Heath · CIK 0001555671 · Chairman, President and CEO

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 267,170

F1 · kind: These Common Stocks were sold in compliance with a qualified selling plan adopted by the reporting person pursuant to Rule 10b5-1 under the Securities Exchange Act of 1934, as amended.

F2 · price: The price reported in Column 4 is a weighted average price and has been rounded to the nearest cent. These Common Stocks were sold in multiple transactions at prices ranging from $35.12 to $35.62, inclusive. The reporting person undertakes to provide to Summit Midstream Corporation, any security holder of Summit Midstream Corporation, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of Common Stocks sold at each separate price within the ranges set forth in footnote 2 to this Form 4.

SEC source: 0002024218-25-000041 · wk-form4_1743037143.xml · nonDerivative · entry 3

Deneke J Heath · CIK 0001555671 · Chairman, President and CEO

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 268,170

F1 · kind: These Common Stocks were sold in compliance with a qualified selling plan adopted by the reporting person pursuant to Rule 10b5-1 under the Securities Exchange Act of 1934, as amended.

F4 · price: The price reported in Column 4 is a weighted average price and has been rounded to the nearest cent. These Common Stocks were sold in multiple transactions at prices ranging from $34.90 to $35.62, inclusive. The reporting person undertakes to provide to Summit Midstream Corporation, any security holder of Summit Midstream Corporation, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of Common Stocks sold at each separate price within the ranges set forth in footnote 4 to this Form 4.

SEC source: 0002024218-25-000041 · wk-form4_1743037143.xml · nonDerivative · entry 2

Deneke J Heath · CIK 0001555671 · Chairman, President and CEO

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 269,170

F1 · kind: These Common Stocks were sold in compliance with a qualified selling plan adopted by the reporting person pursuant to Rule 10b5-1 under the Securities Exchange Act of 1934, as amended.

F3 · price: The price reported in Column 4 is a weighted average price and has been rounded to the nearest cent. These Common Stocks were sold in multiple transactions at prices ranging from $35.52 to $35.96, inclusive. The reporting person undertakes to provide to Summit Midstream Corporation, any security holder of Summit Midstream Corporation, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of Common Stocks sold at each separate price within the ranges set forth in footnote 3 to this Form 4.

SEC source: 0002024218-25-000041 · wk-form4_1743037143.xml · nonDerivative · entry 1

Deneke J Heath · CIK 0001555671 · Chairman, President and CEO

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 270,170

F1 · kind: These Common Stocks were sold in compliance with a qualified selling plan adopted by the reporting person pursuant to Rule 10b5-1 under the Securities Exchange Act of 1934, as amended.

F2 · price: The price reported in Column 4 is a weighted average price and has been rounded to the nearest cent. These Common Stocks were sold in multiple transactions at prices ranging from $35.93 to $36.64, inclusive. The reporting person undertakes to provide to Summit Midstream Corporation, any security holder of Summit Midstream Corporation, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of Common Stocks sold at each separate price within the ranges set forth in footnote 2 to this Form 4.

SEC source: 0002024218-25-000038 · wk-form4_1742596227.xml · nonDerivative · entry 4

Deneke J Heath · CIK 0001555671 · Chairman, President and CEO

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 271,170

F1 · kind: These Common Stocks were sold in compliance with a qualified selling plan adopted by the reporting person pursuant to Rule 10b5-1 under the Securities Exchange Act of 1934, as amended.

F4 · price: The price reported in Column 4 is a weighted average price and has been rounded to the nearest cent. These Common Stocks were sold in multiple transactions at prices ranging from $36.00 to $36.91, inclusive. The reporting person undertakes to provide to Summit Midstream Corporation, any security holder of Summit Midstream Corporation, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of Common Stocks sold at each separate price within the ranges set forth in footnote 4 to this Form 4.

SEC source: 0002024218-25-000038 · wk-form4_1742596227.xml · nonDerivative · entry 3

Deneke J Heath · CIK 0001555671 · Chairman, President and CEO

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 272,170

F1 · kind: These Common Stocks were sold in compliance with a qualified selling plan adopted by the reporting person pursuant to Rule 10b5-1 under the Securities Exchange Act of 1934, as amended.

F3 · price: The price reported in Column 4 is a weighted average price and has been rounded to the nearest cent. These Common Stocks were sold in multiple transactions at prices ranging from $37.39 to $38.26, inclusive. The reporting person undertakes to provide to Summit Midstream Corporation, any security holder of Summit Midstream Corporation, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of Common Stocks sold at each separate price within the ranges set forth in footnote 3 to this Form 4.

SEC source: 0002024218-25-000037 · wk-form4_1742515651.xml · nonDerivative · entry 2

PETERS JERRY L · CIK 0001237636 · Director

10b5-1 filing: No plan indicated

Ownership: Indirect · By Joint Spousal Trust

Disclosed balance after: 23,246

F2 · price: The price reported in Column 4 is a weighted average price and has been rounded to the nearest cent. These Common Stocks were sold in multiple transactions at prices ranging from $37.40 to $37.41, inclusive. The reporting person undertakes to provide to Summit Midstream Corporation, any security holder of Summit Midstream Corporation, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of Common Stocks sold at each separate price within the ranges set forth in footnote 2 to this Form 4.

F1 · ownership.nature: The Reporting Person is a trustee of the Joint Spousal Trust. The Reporting Person and his spouse are the sole beneficiaries of the Joint Spousal Trust.

SEC source: 0002024218-25-000038 · wk-form4_1742596227.xml · nonDerivative · entry 2

Deneke J Heath · CIK 0001555671 · Chairman, President and CEO

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 273,170

F1 · kind: These Common Stocks were sold in compliance with a qualified selling plan adopted by the reporting person pursuant to Rule 10b5-1 under the Securities Exchange Act of 1934, as amended.

SEC source: 0002024218-25-000038 · wk-form4_1742596227.xml · nonDerivative · entry 1

Deneke J Heath · CIK 0001555671 · Chairman, President and CEO

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 273,270

F1 · kind: These Common Stocks were sold in compliance with a qualified selling plan adopted by the reporting person pursuant to Rule 10b5-1 under the Securities Exchange Act of 1934, as amended.

F2 · price: The price reported in Column 4 is a weighted average price and has been rounded to the nearest cent. These Common Stocks were sold in multiple transactions at prices ranging from $37.14 to $38.11, inclusive. The reporting person undertakes to provide to Summit Midstream Corporation, any security holder of Summit Midstream Corporation, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of Common Stocks sold at each separate price within the ranges set forth in footnote 2 to this Form 4.

SEC source: 0002024218-25-000044 · wk-form4a_1745880545.xml · nonDerivative · entry 2

PETERS JERRY L · CIK 0001237636 · Director

10b5-1 filing: No plan indicated

Ownership: Indirect · By Joint Spousal Trust

Disclosed balance after: 20,184

F3 · price: The price reported in Column 4 is a weighted average price and has been rounded to the nearest cent. These Common Stocks were sold in multiple transactions at prices ranging from $37.40 to $37.41, inclusive. The reporting person undertakes to provide to Summit Midstream Corporation, any security holder of Summit Midstream Corporation, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of Common Stocks sold at each separate price within the ranges set forth in footnote 2 to this Form 4.

F1 · balance_after: On March 18, 2025, the Reporting Person filed a Form 4 to report an award of 3,062 common stocks granted on March 14, 2025. But due to administrative error they were reported as being held indirectly by Joint Spousal Trust. The same administrative error was repeated on the Form 4 filed on March 20, 2025. The Form 4 filed on March 18, 2025 has been amended by the Form A filed on April 28, 2025. This Form 4/A amends the Form 4 filed on March 20, 2025, so that such Form 4, as amended, also reflects the 3,062 common stocks directly held by the Reporting Person.

F2 · ownership.nature: The Reporting Person is a trustee of the Joint Spousal Trust. The Reporting Person and his spouse are the sole beneficiaries of the Joint Spousal Trust.

SEC source: 0002024218-25-000033 · wk-form4_1742345407.xml · nonDerivative · entry 10

Deneke J Heath · CIK 0001555671 · Chairman, President and CEO

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 274,170

F3 · kind: These Common Stocks were sold in compliance with a qualified selling plan adopted by the reporting person pursuant to Rule 10b5-1 under the Securities Exchange Act of 1934, as amended.

SEC source: 0002024218-25-000033 · wk-form4_1742345407.xml · nonDerivative · entry 9

Deneke J Heath · CIK 0001555671 · Chairman, President and CEO

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 274,220

F3 · kind: These Common Stocks were sold in compliance with a qualified selling plan adopted by the reporting person pursuant to Rule 10b5-1 under the Securities Exchange Act of 1934, as amended.

F6 · price: The price reported in Column 4 is a weighted average price and has been rounded to the nearest cent. These Common Stocks were sold in multiple transactions at prices ranging from $37.45 to $38.44, inclusive. The reporting person undertakes to provide to Summit Midstream Corporation, any security holder of Summit Midstream Corporation, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of Common Stocks sold at each separate price within the ranges set forth in footnote 6 to this Form 4.

SEC source: 0002024218-25-000037 · wk-form4_1742515651.xml · nonDerivative · entry 1

PETERS JERRY L · CIK 0001237636 · Director

10b5-1 filing: No plan indicated

Ownership: Indirect · By Joint Spousal Trust

Disclosed balance after: 29,946

F1 · ownership.nature: The Reporting Person is a trustee of the Joint Spousal Trust. The Reporting Person and his spouse are the sole beneficiaries of the Joint Spousal Trust.

SEC source: 0002024218-25-000044 · wk-form4a_1745880545.xml · nonDerivative · entry 1

PETERS JERRY L · CIK 0001237636 · Director

10b5-1 filing: No plan indicated

Ownership: Indirect · By Joint Spousal Trust

Disclosed balance after: 26,884

F1 · balance_after: On March 18, 2025, the Reporting Person filed a Form 4 to report an award of 3,062 common stocks granted on March 14, 2025. But due to administrative error they were reported as being held indirectly by Joint Spousal Trust. The same administrative error was repeated on the Form 4 filed on March 20, 2025. The Form 4 filed on March 18, 2025 has been amended by the Form A filed on April 28, 2025. This Form 4/A amends the Form 4 filed on March 20, 2025, so that such Form 4, as amended, also reflects the 3,062 common stocks directly held by the Reporting Person.

F2 · ownership.nature: The Reporting Person is a trustee of the Joint Spousal Trust. The Reporting Person and his spouse are the sole beneficiaries of the Joint Spousal Trust.

SEC source: 0002024218-25-000032 · wk-form4_1742330998.xml · nonDerivative · entry 2

PETERS JERRY L · CIK 0001237636 · Director

10b5-1 filing: No plan indicated

Ownership: Indirect · By Joint Spousal Trust

Disclosed balance after: 29,998

F3 · price: The price reported in Column 4 has been rounded to the nearest cent.

F2 · ownership.nature: The Reporting Person is a trustee of the Joint Spousal Trust. The Reporting Person and his spouse are the sole beneficiaries of the Joint Spousal Trust.

SEC source: 0002024218-25-000033 · wk-form4_1742345407.xml · nonDerivative · entry 8

Deneke J Heath · CIK 0001555671 · Chairman, President and CEO

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 275,170

F3 · kind: These Common Stocks were sold in compliance with a qualified selling plan adopted by the reporting person pursuant to Rule 10b5-1 under the Securities Exchange Act of 1934, as amended.

F5 · price: The price reported in Column 4 is a weighted average price and has been rounded to the nearest cent. These Common Stocks were sold in multiple transactions at prices ranging from $38.78 to $39.35, inclusive. The reporting person undertakes to provide to Summit Midstream Corporation, any security holder of Summit Midstream Corporation, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of Common Stocks sold at each separate price within the ranges set forth in footnote 5 to this Form 4.

SEC source: 0002024218-25-000033 · wk-form4_1742345407.xml · nonDerivative · entry 7

Deneke J Heath · CIK 0001555671 · Chairman, President and CEO

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 275,637

F3 · kind: These Common Stocks were sold in compliance with a qualified selling plan adopted by the reporting person pursuant to Rule 10b5-1 under the Securities Exchange Act of 1934, as amended.

F4 · price: The price reported in Column 4 is a weighted average price and has been rounded to the nearest cent. These Common Stocks were sold in multiple transactions at prices ranging from $37.76 to $38.66, inclusive. The reporting person undertakes to provide to Summit Midstream Corporation, any security holder of Summit Midstream Corporation, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of Common Stocks sold at each separate price within the ranges set forth in footnote 4 to this Form 4.

SEC source: 0002024218-25-000043 · wk-form4a_1745880334.xml · nonDerivative · entry 2

PETERS JERRY L · CIK 0001237636 · Director

10b5-1 filing: No plan indicated

Ownership: Indirect · By Joint Spousal Trust

Disclosed balance after: 26,936

F2 · price: The price reported in Column 4 has been rounded to the nearest cent.

F3 · ownership.direct: The common stocks which due to administrative error were previously reported as being held directly, are held indirectly by Joint Spousal Trust.

F4 · ownership.nature: The Reporting Person is a trustee of the Joint Spousal Trust. The Reporting Person and his spouse are the sole beneficiaries of the Joint Spousal Trust.

SEC source: 0002024218-25-000036 · wk-form4_1742345869.xml · derivative · entry 11

Sicinski Matthew B. · CIK 0001911802 · Senior VP and CAO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 32,955

Underlying: Common Stock · 3,175 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_price: Each corporation restricted stock unit is the economic equivalent of one common stock.

F8 · derivative.exercise_date: One-third of the corporation restricted stock units subject to the original award agreement vested on March 15, 2025, and the final one-third of the corporation restricted stock units shall vest on the third anniversary of the March 15, 2023, reference date, subject to continued employment. The Reporting Person received DERs for each corporation restricted stock unit, providing for payment on the vesting date of a lump sum of cash equal to the accrued distributions from and after the grant date of the corporation restricted stock units.

F4 · derivative.expiration_date: The corporation restricted stock units and associated DERs do not expire. The corporation restricted stock units are settled upon vesting in common stocks (on a one-for-one basis) or in cash, at the discretion of the Issuer.

SEC source: 0002024218-25-000036 · wk-form4_1742345869.xml · derivative · entry 10

Sicinski Matthew B. · CIK 0001911802 · Senior VP and CAO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 36,130

Underlying: Common Stock · 2,531 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_price: Each corporation restricted stock unit is the economic equivalent of one common stock.

F7 · derivative.exercise_date: The final twenty percent of the corporation restricted stock units subject to the original award agreement vested on March 15, 2025, the third anniversary of the March 15, 2022, reference date. The Reporting Person received DERs for each corporation restricted stock unit, providing for payment on the vesting date of a lump sum of cash equal to the accrued distributions from and after the grant date of the corporation restricted stock units.

F4 · derivative.expiration_date: The corporation restricted stock units and associated DERs do not expire. The corporation restricted stock units are settled upon vesting in common stocks (on a one-for-one basis) or in cash, at the discretion of the Issuer.

SEC source: 0002024218-25-000036 · wk-form4_1742345869.xml · derivative · entry 9

Sicinski Matthew B. · CIK 0001911802 · Senior VP and CAO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 38,661

Underlying: Common Stock · 1,746 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_price: Each corporation restricted stock unit is the economic equivalent of one common stock.

F6 · derivative.exercise_date: The final one-third of the corporation restricted stock units subject to the original award agreement vested on March 15, 2025, the third anniversary of the March 15, 2022, reference date. The Reporting Person received DERs for each corporation restricted stock unit, providing for payment on the vesting date of a lump sum of cash equal to the accrued distributions from and after the grant date of the corporation restricted stock units.

F4 · derivative.expiration_date: The corporation restricted stock units and associated DERs do not expire. The corporation restricted stock units are settled upon vesting in common stocks (on a one-for-one basis) or in cash, at the discretion of the Issuer.

SEC source: 0002024218-25-000036 · wk-form4_1742345869.xml · nonDerivative · entry 6

Sicinski Matthew B. · CIK 0001911802 · Senior VP and CAO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 28,820

F2 · shares: Common stocks being withheld to pay tax liability.

SEC source: 0002024218-25-000036 · wk-form4_1742345869.xml · nonDerivative · entry 5

Sicinski Matthew B. · CIK 0001911802 · Senior VP and CAO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 29,594

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · price: Each corporation restricted stock unit is the economic equivalent of one common stock.

SEC source: 0002024218-25-000036 · wk-form4_1742345869.xml · nonDerivative · entry 4

Sicinski Matthew B. · CIK 0001911802 · Senior VP and CAO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 26,419

F2 · shares: Common stocks being withheld to pay tax liability.

SEC source: 0002024218-25-000036 · wk-form4_1742345869.xml · nonDerivative · entry 3

Sicinski Matthew B. · CIK 0001911802 · Senior VP and CAO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 27,036

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · price: Each corporation restricted stock unit is the economic equivalent of one common stock.

SEC source: 0002024218-25-000036 · wk-form4_1742345869.xml · nonDerivative · entry 2

Sicinski Matthew B. · CIK 0001911802 · Senior VP and CAO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 24,505

F2 · shares: Common stocks being withheld to pay tax liability.