WES

SEC source: 0001423902-25-000010 · wk-form4_1739567562.xml · nonDerivative · entry 6

Green Catherine A. · CIK 0001791874 · SVP & Chief Accounting Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 63,928

SEC source: 0001423902-25-000010 · wk-form4_1739567562.xml · nonDerivative · entry 5

Green Catherine A. · CIK 0001791874 · SVP & Chief Accounting Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 68,632

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.

SEC source: 0001423902-25-000010 · wk-form4_1739567562.xml · nonDerivative · entry 4

Green Catherine A. · CIK 0001791874 · SVP & Chief Accounting Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 56,680

SEC source: 0001423902-25-000010 · wk-form4_1739567562.xml · nonDerivative · entry 3

Green Catherine A. · CIK 0001791874 · SVP & Chief Accounting Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 59,442

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.

SEC source: 0001423902-25-000010 · wk-form4_1739567562.xml · nonDerivative · entry 2

Green Catherine A. · CIK 0001791874 · SVP & Chief Accounting Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 52,424

SEC source: 0001423902-25-000010 · wk-form4_1739567562.xml · nonDerivative · entry 1

Green Catherine A. · CIK 0001791874 · SVP & Chief Accounting Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 54,140

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.

SEC source: 0001423902-25-000011 · wk-form4_1739567633.xml · derivative · entry 9

Forsyth Michael S. · CIK 0001949639 · SVP, North Operations

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 29,879

Underlying: Common Units representing limited partner interests · 14,940 shares

Expires 2027-02-12

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 Phantom Unit is the economic equivalent of one WES Common Unit representing limited partnership interests, and upon vesting, will entitle the holder to receive a common unit or, at the discretion of the Board of Directors of the General Partner, cash equal to the Fair Market Value of a Common Unit.

F2 · derivative.exercise_date: These Phantom Units vest ratably over a three-year period on February 12th of each year, and will pay distribution equivalent rights in cash on a current basis.

SEC source: 0001423902-25-000011 · wk-form4_1739567633.xml · derivative · entry 8

Forsyth Michael S. · CIK 0001949639 · SVP, North Operations

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 10,819

Underlying: Common Units representing limited partner interests · 10,819 shares

Expires 2026-02-12

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 Phantom Unit is the economic equivalent of one WES Common Unit representing limited partnership interests, and upon vesting, will entitle the holder to receive a common unit or, at the discretion of the Board of Directors of the General Partner, cash equal to the Fair Market Value of a Common Unit.

F2 · derivative.exercise_date: These Phantom Units vest ratably over a three-year period on February 12th of each year, and will pay distribution equivalent rights in cash on a current basis.

SEC source: 0001423902-25-000011 · wk-form4_1739567633.xml · derivative · entry 7

Forsyth Michael S. · CIK 0001949639 · SVP, North Operations

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Units representing limited partner interests · 2,789 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 Phantom Unit is the economic equivalent of one WES Common Unit representing limited partnership interests, and upon vesting, will entitle the holder to receive a common unit or, at the discretion of the Board of Directors of the General Partner, cash equal to the Fair Market Value of a Common Unit.

F2 · derivative.exercise_date: These Phantom Units vest ratably over a three-year period on February 12th of each year, and will pay distribution equivalent rights in cash on a current basis.

F2 · derivative.expiration_date: These Phantom Units vest ratably over a three-year period on February 12th of each year, and will pay distribution equivalent rights in cash on a current basis.

SEC source: 0001423902-25-000011 · wk-form4_1739567633.xml · nonDerivative · entry 6

Forsyth Michael S. · CIK 0001949639 · SVP, North Operations

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 42,327

SEC source: 0001423902-25-000011 · wk-form4_1739567633.xml · nonDerivative · entry 5

Forsyth Michael S. · CIK 0001949639 · SVP, North Operations

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 48,864

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.

SEC source: 0001423902-25-000011 · wk-form4_1739567633.xml · nonDerivative · entry 4

Forsyth Michael S. · CIK 0001949639 · SVP, North Operations

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 33,924

SEC source: 0001423902-25-000011 · wk-form4_1739567633.xml · nonDerivative · entry 3

Forsyth Michael S. · CIK 0001949639 · SVP, North Operations

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 38,658

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.

SEC source: 0001423902-25-000011 · wk-form4_1739567633.xml · nonDerivative · entry 2

Forsyth Michael S. · CIK 0001949639 · SVP, North Operations

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 27,839

SEC source: 0001423902-25-000011 · wk-form4_1739567633.xml · nonDerivative · entry 1

Forsyth Michael S. · CIK 0001949639 · SVP, North Operations

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 29,101

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.

SEC source: 0001423902-25-000009 · wk-form4_1739567440.xml · derivative · entry 9

Bourne Robert W. · CIK 0001627376 · SVP & Chief Commercial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 29,879

Underlying: Common Units representing limited partner interests · 14,940 shares

Expires 2027-02-12

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.

F3 · derivative.exercise_price: Each Phantom Unit is the economic equivalent of one WES Common Unit representing limited partnership interests, and upon vesting, will entitle the holder to receive a common unit or, at the discretion of the Board of Directors of the General Partner, cash equal to the Fair Market Value of a Common Unit.

F4 · derivative.exercise_date: These Phantom Units vest ratably over a three-year period on February 12th of each year, and will pay distribution equivalent rights in cash on a current basis.

SEC source: 0001423902-25-000009 · wk-form4_1739567440.xml · derivative · entry 8

Bourne Robert W. · CIK 0001627376 · SVP & Chief Commercial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 10,819

Underlying: Common Units representing limited partner interests · 10,819 shares

Expires 2026-02-12

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.

F3 · derivative.exercise_price: Each Phantom Unit is the economic equivalent of one WES Common Unit representing limited partnership interests, and upon vesting, will entitle the holder to receive a common unit or, at the discretion of the Board of Directors of the General Partner, cash equal to the Fair Market Value of a Common Unit.

F4 · derivative.exercise_date: These Phantom Units vest ratably over a three-year period on February 12th of each year, and will pay distribution equivalent rights in cash on a current basis.

SEC source: 0001423902-25-000009 · wk-form4_1739567440.xml · derivative · entry 7

Bourne Robert W. · CIK 0001627376 · SVP & Chief Commercial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Units representing limited partner interests · 5,781 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 Phantom Unit is the economic equivalent of one WES Common Unit representing limited partnership interests, and upon vesting, entitled to receive a common unit

F2 · derivative.exercise_date: The phantom units vest in three annual installments beginning one year after the date of grant, and will pay distribution equivalent rights prior to vesting in the form of WES Common Units.

F2 · derivative.expiration_date: The phantom units vest in three annual installments beginning one year after the date of grant, and will pay distribution equivalent rights prior to vesting in the form of WES Common Units.

SEC source: 0001423902-25-000009 · wk-form4_1739567440.xml · nonDerivative · entry 6

Bourne Robert W. · CIK 0001627376 · SVP & Chief Commercial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 149,714.873

SEC source: 0001423902-25-000009 · wk-form4_1739567440.xml · nonDerivative · entry 5

Bourne Robert W. · CIK 0001627376 · SVP & Chief Commercial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 155,593.873

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.

SEC source: 0001423902-25-000009 · wk-form4_1739567440.xml · nonDerivative · entry 4

Bourne Robert W. · CIK 0001627376 · SVP & Chief Commercial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 140,653.873

SEC source: 0001423902-25-000009 · wk-form4_1739567440.xml · nonDerivative · entry 3

Bourne Robert W. · CIK 0001627376 · SVP & Chief Commercial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 144,911.873

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.

SEC source: 0001423902-25-000009 · wk-form4_1739567440.xml · nonDerivative · entry 2

Bourne Robert W. · CIK 0001627376 · SVP & Chief Commercial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 134,092.873

SEC source: 0001423902-25-000009 · wk-form4_1739567440.xml · nonDerivative · entry 1

Bourne Robert W. · CIK 0001627376 · SVP & Chief Commercial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 136,405.873

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.

SEC source: 0001423902-25-000007 · wk-form4_1739567322.xml · derivative · entry 9

Shults Kristen S. · CIK 0001925496 · SVP & Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 29,879

Underlying: Common Units representing limited partner interests · 14,940 shares

Expires 2027-02-12

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 Phantom Unit is the economic equivalent of one WES Common Unit representing limited partnership interests, and upon vesting, will entitle the holder to receive a common unit or, at the discretion of the Board of Directors of the General Partner, cash equal to the Fair Market Value of a Common Unit.

F2 · derivative.exercise_date: These Phantom Units vest ratably over a three-year period on February 12th of each year, and will pay distribution equivalent rights in cash on a current basis.

SEC source: 0001423902-25-000007 · wk-form4_1739567322.xml · derivative · entry 8

Shults Kristen S. · CIK 0001925496 · SVP & Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 10,819

Underlying: Common Units representing limited partner interests · 10,819 shares

Expires 2026-02-12

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 Phantom Unit is the economic equivalent of one WES Common Unit representing limited partnership interests, and upon vesting, will entitle the holder to receive a common unit or, at the discretion of the Board of Directors of the General Partner, cash equal to the Fair Market Value of a Common Unit.

F2 · derivative.exercise_date: These Phantom Units vest ratably over a three-year period on February 12th of each year, and will pay distribution equivalent rights in cash on a current basis.

SEC source: 0001423902-25-000007 · wk-form4_1739567322.xml · derivative · entry 7

Shults Kristen S. · CIK 0001925496 · SVP & Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Units representing limited partner interests · 15,511 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 Phantom Unit is the economic equivalent of one WES Common Unit representing limited partnership interests, and upon vesting, will entitle the holder to receive a common unit or, at the discretion of the Board of Directors of the General Partner, cash equal to the Fair Market Value of a Common Unit.

F2 · derivative.exercise_date: These Phantom Units vest ratably over a three-year period on February 12th of each year, and will pay distribution equivalent rights in cash on a current basis.

F2 · derivative.expiration_date: These Phantom Units vest ratably over a three-year period on February 12th of each year, and will pay distribution equivalent rights in cash on a current basis.

SEC source: 0001423902-25-000007 · wk-form4_1739567322.xml · nonDerivative · entry 6

Shults Kristen S. · CIK 0001925496 · SVP & Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 65,998

SEC source: 0001423902-25-000007 · wk-form4_1739567322.xml · nonDerivative · entry 5

Shults Kristen S. · CIK 0001925496 · SVP & Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 71,877

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.

SEC source: 0001423902-25-000007 · wk-form4_1739567322.xml · nonDerivative · entry 4

Shults Kristen S. · CIK 0001925496 · SVP & Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 56,937

SEC source: 0001423902-25-000007 · wk-form4_1739567322.xml · nonDerivative · entry 3

Shults Kristen S. · CIK 0001925496 · SVP & Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 61,195

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.

SEC source: 0001423902-25-000007 · wk-form4_1739567322.xml · nonDerivative · entry 2

Shults Kristen S. · CIK 0001925496 · SVP & Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 50,376

SEC source: 0001423902-25-000007 · wk-form4_1739567322.xml · nonDerivative · entry 1

Shults Kristen S. · CIK 0001925496 · SVP & Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 56,508

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.

SEC source: 0001423902-25-000006 · wk-form4_1739567255.xml · derivative · entry 9

Holderman Daniel P. · CIK 0001942513 · SVP & Chief Operating Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 29,879

Underlying: Common Units representing limited partner interests · 14,940 shares

Expires 2027-02-12

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 Phantom Unit is the economic equivalent of one WES Common Unit representing limited partnership interests, and upon vesting, will entitle the holder to receive a common unit or, at the discretion of the Board of Directors of the General Partner, cash equal to the Fair Market Value of a Common Unit.

F3 · derivative.exercise_date: These Phantom Units vest ratably over a three-year period on February 12th of each year, and will pay distribution equivalent rights in cash on a current basis.

SEC source: 0001423902-25-000006 · wk-form4_1739567255.xml · derivative · entry 8

Holderman Daniel P. · CIK 0001942513 · SVP & Chief Operating Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 10,819

Underlying: Common Units representing limited partner interests · 10,819 shares

Expires 2026-02-12

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 Phantom Unit is the economic equivalent of one WES Common Unit representing limited partnership interests, and upon vesting, will entitle the holder to receive a common unit or, at the discretion of the Board of Directors of the General Partner, cash equal to the Fair Market Value of a Common Unit.

F3 · derivative.exercise_date: These Phantom Units vest ratably over a three-year period on February 12th of each year, and will pay distribution equivalent rights in cash on a current basis.

SEC source: 0001423902-25-000006 · wk-form4_1739567255.xml · derivative · entry 7

Holderman Daniel P. · CIK 0001942513 · SVP & Chief Operating Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Units representing limited partner interests · 7,055 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 Phantom Unit is the economic equivalent of one WES Common Unit representing limited partnership interests, and upon vesting, will entitle the holder to receive a common unit or, at the discretion of the Board of Directors of the General Partner, cash equal to the Fair Market Value of a Common Unit.

F2 · derivative.exercise_date: The Phantom Units vest in three annual installments 20% on February 12, 2023, 40% on February 12, 2024, and 40% on February 12, 2025, and will pay distribution equivalent rights in cash prior to vesting.

F2 · derivative.expiration_date: The Phantom Units vest in three annual installments 20% on February 12, 2023, 40% on February 12, 2024, and 40% on February 12, 2025, and will pay distribution equivalent rights in cash prior to vesting.

SEC source: 0001423902-25-000006 · wk-form4_1739567255.xml · nonDerivative · entry 6

Holderman Daniel P. · CIK 0001942513 · SVP & Chief Operating Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 35,748

SEC source: 0001423902-25-000006 · wk-form4_1739567255.xml · nonDerivative · entry 5

Holderman Daniel P. · CIK 0001942513 · SVP & Chief Operating Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 41,627

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.

SEC source: 0001423902-25-000006 · wk-form4_1739567255.xml · nonDerivative · entry 4

Holderman Daniel P. · CIK 0001942513 · SVP & Chief Operating Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 26,687

SEC source: 0001423902-25-000006 · wk-form4_1739567255.xml · nonDerivative · entry 3

Holderman Daniel P. · CIK 0001942513 · SVP & Chief Operating Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 30,945

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.

SEC source: 0001423902-25-000006 · wk-form4_1739567255.xml · nonDerivative · entry 2

Holderman Daniel P. · CIK 0001942513 · SVP & Chief Operating Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 20,126

SEC source: 0001423902-25-000006 · wk-form4_1739567255.xml · nonDerivative · entry 1

Holderman Daniel P. · CIK 0001942513 · SVP & Chief Operating Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 22,942

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.

SEC source: 0001423902-25-000004 · wk-form4_1739567116.xml · derivative · entry 2

Owen Kenneth F. · CIK 0001523426 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Units representing limited partner interests · 5,199 shares

Expires 2025-02-12

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 Phantom Unit is the economic equivalent of one WES Common Unit representing limited partnership interests, and upon vesting, will entitle the holder to receive a common unit or, at the discretion of the Board of Directors of the General Partner, cash equal to the Fair Market Value of a Common Unit.

SEC source: 0001423902-25-000004 · wk-form4_1739567116.xml · nonDerivative · entry 1

Owen Kenneth F. · CIK 0001523426 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 37,929

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.

SEC source: 0001423902-25-000003 · wk-form4_1739567045.xml · derivative · entry 2

STEWART LISA A · CIK 0001244213 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Units representing limited partner interests · 5,199 shares

Expires 2025-02-12

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 Phantom Unit is the economic equivalent of one WES Common Unit representing limited partnership interests, and upon vesting, will entitle the holder to receive a common unit or, at the discretion of the Board of Directors of the General Partner, cash equal to the Fair Market Value of a Common Unit.

SEC source: 0001423902-25-000003 · wk-form4_1739567045.xml · nonDerivative · entry 1

STEWART LISA A · CIK 0001244213 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 35,929

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.

SEC source: 0001423902-25-000002 · wk-form4_1739566853.xml · derivative · entry 2

Brown Oscar K · CIK 0001715126 · Director · President & CEO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Units representing limited partner interests · 5,199 shares

Expires 2025-02-12

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 Phantom Unit is the economic equivalent of one WES Common Unit representing limited partnership interests, and upon vesting, will entitle the holder to receive a common unit or, at the discretion of the Board of Directors of the General Partner, cash equal to the Fair Market Value of a Common Unit.

SEC source: 0001423902-25-000002 · wk-form4_1739566853.xml · nonDerivative · entry 1

Brown Oscar K · CIK 0001715126 · Director · President & CEO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 39,990

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.

SEC source: 0001423902-24-000071 · wk-form4_1730326439.xml · derivative · entry 3

Brown Oscar K · CIK 0001715126 · Director · President & CEO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 157,978

Underlying: Common Units representing limited partner interests · 157,978 shares

Expires 2027-10-28

F1 · derivative.exercise_price: Each Phantom Unit is the economic equivalent of one WES Common Unit representing limited partnership interests, and upon vesting, will entitle the holder to receive a common unit or, at the discretion of the Board of Directors of the General Partner, cash equal to the Fair Market Value of a Common Unit.

F2 · derivative.exercise_date: These Phantom Units vest ratably over a three-year period on October 28th each year, and will pay distribution equivalent rights in cash on a current basis.

SEC source: 0000797468-24-000146 · wk-form4_1723842705.xml · nonDerivative · entry 1

OCCIDENTAL PETROLEUM CORP /DE/ · CIK 0000797468 · 10% owner

OXY USA INC · CIK 0000728399 · 10% owner

OXY Oil Partners, Inc. · CIK 0001785615 · 10% owner

Baseball Merger Sub 2, Inc. · CIK 0001785593 · 10% owner

ANADARKO PETROLEUM CORP · CIK 0000773910 · 10% owner

ANADARKO HOLDING Co · CIK 0001570992 · 10% owner

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

10b5-1 filing: No plan indicated

Ownership: Indirect · See Footnotes

Disclosed balance after: 165,681,578

F1 · kind: On August 14, 2024, WGR Asset Holding Company LLC ("WGRAH") and Anadarko USH1 Corporation ("AUSH1") sold 14,139,260 and 5,360,740 common units representing limited partner interests in the Issuer (the "Common Units"), respectively, in an underwritten public offering at a price of $35.75 per Common Unit.

F1 · price: On August 14, 2024, WGR Asset Holding Company LLC ("WGRAH") and Anadarko USH1 Corporation ("AUSH1") sold 14,139,260 and 5,360,740 common units representing limited partner interests in the Issuer (the "Common Units"), respectively, in an underwritten public offering at a price of $35.75 per Common Unit.

F2 · ownership.nature: Following the transaction reported herein, Western Gas Resources, Inc. ("WGRI") holds 156,219,520 Common Units, APC Midstream Holdings, LLC ("APCMH") holds 457,849 Common Units and AUSHI holds 9,004,209 Common Units. WGRI also is the sole member of Western Midstream Holdings, LLC, the 2% economic general partner of the Issuer.

F3 · ownership.nature: OXY USA Inc. ("OXY USA") is a wholly owned subsidiary of Occidental Petroleum Corporation ("Occidental"). OXY USA owns 100% of the outstanding common stock of OXY Oil Partners, Inc. ("OOP"). OOP owns 100% of the outstanding common stock of Baseball Merger Sub 2, Inc. ("BMS").

F4 · ownership.nature: Anadarko Petroleum Corporation ("APC") is a wholly owned subsidiary of BMS. APC owns (i) 100% of Anadarko Holding Company ("AHC") and (ii) indirectly, 100% of the common stock of WGRI and Kerr-McGee Corporation ("KMG"). WGRI is the sole member of APCMH. KMG and AHC together own 100% of the common stock of Kerr-McGee Worldwide Corporation ("KMWW"), and APC and KMWW together indirectly own 100% of the common stock of AUSH1. Accordingly, OXY USA, OOP, BMS, APC, AHC, WGRI, AUSH1, KMG, APCMH, KMWW and WGRAH are all direct or indirect wholly owned subsidiaries of Occidental.