Apostolou Stephanie L

SEC source: 0001315257-26-000014 · wk-form4_1772485987.xml · derivative · entry 5

Apostolou Stephanie L · CIK 0001806249 · Chief Legal&Sus Officer & Sec.

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 148

Underlying: Common Stock · 174 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.

F5 · derivative.exercise_price: These DERs were released in connection with the vesting of PSUs granted on January 4, 2023. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

F5 · shares: These DERs were released in connection with the vesting of PSUs granted on January 4, 2023. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

F5 · derivative.exercise_date: These DERs were released in connection with the vesting of PSUs granted on January 4, 2023. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

F5 · derivative.expiration_date: These DERs were released in connection with the vesting of PSUs granted on January 4, 2023. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

SEC source: 0001315257-26-000014 · wk-form4_1772485987.xml · derivative · entry 4

Apostolou Stephanie L · CIK 0001806249 · Chief Legal&Sus Officer & Sec.

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 322

Underlying: Common Stock · 174 shares

Expires not disclosed

F4 · derivative.exercise_price: The DERs accrued with respect to additional PSUs credited to the reporting person with respect to PSUs granted on January 4, 2023. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

F4 · derivative.exercise_date: The DERs accrued with respect to additional PSUs credited to the reporting person with respect to PSUs granted on January 4, 2023. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

F4 · derivative.expiration_date: The DERs accrued with respect to additional PSUs credited to the reporting person with respect to PSUs granted on January 4, 2023. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

SEC source: 0001315257-26-000014 · wk-form4_1772485987.xml · nonDerivative · entry 3

Apostolou Stephanie L · CIK 0001806249 · Chief Legal&Sus Officer & Sec.

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 63,150

F3 · price: Shares surrendered to the issuer by the reporting person as payment for the tax withholding related to the vesting of PSUs.

SEC source: 0001315257-26-000014 · wk-form4_1772485987.xml · nonDerivative · entry 2

Apostolou Stephanie L · CIK 0001806249 · Chief Legal&Sus Officer & Sec.

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 66,299

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.

F2 · shares: Represents shares acquired upon release of dividend equivalent rights ("DERs"), as reported in Table II, on a one-for-one basis.

F2 · price: Represents shares acquired upon release of dividend equivalent rights ("DERs"), as reported in Table II, on a one-for-one basis.

SEC source: 0001315257-26-000014 · wk-form4_1772485987.xml · nonDerivative · entry 1

Apostolou Stephanie L · CIK 0001806249 · Chief Legal&Sus Officer & Sec.

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 66,125

F1 · security: On January 4, 2023, the reporting person was granted performance share units ("PSUs") for which the performance criteria for the measurement period from January 1, 2023 through December 31, 2025 have been satisfied.

SEC source: 0001806249-26-000002 · wk-form4_1767740573.xml · derivative · entry 9

Apostolou Stephanie L · CIK 0001806249 · Chief Legal&Sus Officer & Sec.

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 148

Underlying: Common Stock · 240 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.

F10 · derivative.exercise_price: These DERs were released in connection with the vesting of RSUs and PSUs granted on January 4, 2022, January 4, 2023, January 4, 2024, and January 3, 2025. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

F10 · shares: These DERs were released in connection with the vesting of RSUs and PSUs granted on January 4, 2022, January 4, 2023, January 4, 2024, and January 3, 2025. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

F10 · derivative.exercise_date: These DERs were released in connection with the vesting of RSUs and PSUs granted on January 4, 2022, January 4, 2023, January 4, 2024, and January 3, 2025. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

F10 · derivative.expiration_date: These DERs were released in connection with the vesting of RSUs and PSUs granted on January 4, 2022, January 4, 2023, January 4, 2024, and January 3, 2025. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

SEC source: 0001806249-26-000002 · wk-form4_1767740573.xml · derivative · entry 8

Apostolou Stephanie L · CIK 0001806249 · Chief Legal&Sus Officer & Sec.

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 4,666 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.

F3 · derivative.exercise_price: Restricted stock units convert into common stock on a one-for-one basis.

F9 · derivative.exercise_date: Represents previously granted PSUs for which the performance criteria for the three-year performance period from January 1, 2023 through December 31, 2025 have been satisfied, as reported in Table II above.

F9 · derivative.expiration_date: Represents previously granted PSUs for which the performance criteria for the three-year performance period from January 1, 2023 through December 31, 2025 have been satisfied, as reported in Table II above.

SEC source: 0001806249-26-000002 · wk-form4_1767740573.xml · nonDerivative · entry 4

Apostolou Stephanie L · CIK 0001806249 · Chief Legal&Sus Officer & Sec.

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 58,902

F5 · price: Shares surrendered to the issuer by the reporting person as payment for the tax withholding related to the vesting of RSUs and performance share units ("PSUs").

SEC source: 0001806249-26-000002 · wk-form4_1767740573.xml · nonDerivative · entry 3

Apostolou Stephanie L · CIK 0001806249 · Chief Legal&Sus Officer & Sec.

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 64,659

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.

F4 · shares: Represents shares acquired upon release of dividend equivalent rights ("DERs"), as reported in Table II, on a one-for-one basis.

F4 · price: Represents shares acquired upon release of dividend equivalent rights ("DERs"), as reported in Table II, on a one-for-one basis.

SEC source: 0001806249-26-000002 · wk-form4_1767740573.xml · nonDerivative · entry 2

Apostolou Stephanie L · CIK 0001806249 · Chief Legal&Sus Officer & Sec.

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 64,419

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 · price: Restricted stock units convert into common stock on a one-for-one basis.

SEC source: 0001806249-26-000002 · wk-form4_1767740573.xml · nonDerivative · entry 1

Apostolou Stephanie L · CIK 0001806249 · Chief Legal&Sus Officer & Sec.

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 59,753

F1 · security: The reporting person was awarded time-based restricted stock units ("RSUs") on January 5, 2026, which will vest in annual installments of 25 percent over four years.

F2 · balance_after: Includes 828 shares of Koppers Holdings Inc. common stock acquired pursuant to the Koppers Holdings Inc. Employee Stock Purchase Plan on March 31, 2025 and June 30, 2025. These acquisitions were exempt under both Rule 16b-3(c) and Rule 16b-3(d).

SEC source: 0001806249-26-000002 · wk-form4_1767740573.xml · derivative · entry 7

Apostolou Stephanie L · CIK 0001806249 · Chief Legal&Sus Officer & Sec.

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 388

Underlying: Common Stock · 39 shares

Expires not disclosed

F8 · derivative.exercise_price: The DERs accrued with respect to additional PSUs credited to the reporting person with respect to PSUs granted on January 4, 2023 and January 3, 2025. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

F8 · derivative.exercise_date: The DERs accrued with respect to additional PSUs credited to the reporting person with respect to PSUs granted on January 4, 2023 and January 3, 2025. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

F8 · derivative.expiration_date: The DERs accrued with respect to additional PSUs credited to the reporting person with respect to PSUs granted on January 4, 2023 and January 3, 2025. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

SEC source: 0001806249-26-000002 · wk-form4_1767740573.xml · derivative · entry 6

Apostolou Stephanie L · CIK 0001806249 · Chief Legal&Sus Officer & Sec.

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 1,335

Underlying: Common Stock · 1,335 shares

Expires not disclosed

F3 · derivative.exercise_price: Restricted stock units convert into common stock on a one-for-one basis.

F7 · derivative.exercise_date: On January 3, 2025, the reporting person was granted PSUs for which the performance criteria for the one-year performance period from January 1, 2025 through December 31, 2025 have been satisfied. All of the restricted stock units reported here are subject to vesting based on the continued service of the reporting person through January 5, 2028. If the Company's total shareholder return over the three-year period of January 1, 2025 through December 31, 2027 is negative, then the cumulative number of units that may vest for such three-year period will be capped at 150% of the target number.

F7 · derivative.expiration_date: On January 3, 2025, the reporting person was granted PSUs for which the performance criteria for the one-year performance period from January 1, 2025 through December 31, 2025 have been satisfied. All of the restricted stock units reported here are subject to vesting based on the continued service of the reporting person through January 5, 2028. If the Company's total shareholder return over the three-year period of January 1, 2025 through December 31, 2027 is negative, then the cumulative number of units that may vest for such three-year period will be capped at 150% of the target number.

SEC source: 0001806249-26-000002 · wk-form4_1767740573.xml · derivative · entry 5

Apostolou Stephanie L · CIK 0001806249 · Chief Legal&Sus Officer & Sec.

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 4,666

Underlying: Common Stock · 1,153 shares

Expires not disclosed

F3 · derivative.exercise_price: Restricted stock units convert into common stock on a one-for-one basis.

F6 · derivative.exercise_date: On January 4, 2023, the reporting person was granted PSUs for which the performance criteria for the three-year performance period from January 1, 2023 through December 31, 2025 have been satisfied.

F6 · derivative.expiration_date: On January 4, 2023, the reporting person was granted PSUs for which the performance criteria for the three-year performance period from January 1, 2023 through December 31, 2025 have been satisfied.

SEC source: 0001806249-25-000003 · wk-form4_1766013013.xml · derivative · entry 1

Apostolou Stephanie L · CIK 0001806249 · Chief Legal&Sus Officer & Sec.

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 349

Underlying: Common Stock · 245 shares

Expires not disclosed

F1 · derivative.exercise_price: The dividend equivalent rights ("DERs") accrued with respect to additional time-based and performance-based restricted stock units ("RSUs" and "PSUs", respectively) credited to the reporting person. Of this total, 208 DERs accrued with respect to RSUs granted on January 4, 2022, January 4, 2023, January 4, 2024, and January 3, 2025, and 37 DERs accrued with respect to PSUs granted on January 4, 2023. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

F1 · derivative.exercise_date: The dividend equivalent rights ("DERs") accrued with respect to additional time-based and performance-based restricted stock units ("RSUs" and "PSUs", respectively) credited to the reporting person. Of this total, 208 DERs accrued with respect to RSUs granted on January 4, 2022, January 4, 2023, January 4, 2024, and January 3, 2025, and 37 DERs accrued with respect to PSUs granted on January 4, 2023. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

F1 · derivative.expiration_date: The dividend equivalent rights ("DERs") accrued with respect to additional time-based and performance-based restricted stock units ("RSUs" and "PSUs", respectively) credited to the reporting person. Of this total, 208 DERs accrued with respect to RSUs granted on January 4, 2022, January 4, 2023, January 4, 2024, and January 3, 2025, and 37 DERs accrued with respect to PSUs granted on January 4, 2023. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

SEC source: 0000950170-25-002821 · ownership.xml · derivative · entry 9

Apostolou Stephanie L · CIK 0001806249 · Chief Legal&Sus Officer & Sec.

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 104

Underlying: Common Stock · 210 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.

F10 · derivative.exercise_price: These DERs were released in connection with the vesting of RSUs and PSUs granted on January 4, 2021, January 4, 2022, January 4, 2023, and January 4, 2024. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

F10 · shares: These DERs were released in connection with the vesting of RSUs and PSUs granted on January 4, 2021, January 4, 2022, January 4, 2023, and January 4, 2024. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

F10 · derivative.exercise_date: These DERs were released in connection with the vesting of RSUs and PSUs granted on January 4, 2021, January 4, 2022, January 4, 2023, and January 4, 2024. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

F10 · derivative.expiration_date: These DERs were released in connection with the vesting of RSUs and PSUs granted on January 4, 2021, January 4, 2022, January 4, 2023, and January 4, 2024. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

SEC source: 0000950170-25-002821 · ownership.xml · derivative · entry 8

Apostolou Stephanie L · CIK 0001806249 · Chief Legal&Sus Officer & Sec.

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 6,867 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.

F3 · derivative.exercise_price: Restricted stock units convert into common stock on a one-for-one basis.

F9 · derivative.exercise_date: Represents previously granted PSUs for which the performance criteria for the three-year performance period from January 1, 2022 through December 31, 2024 have been satisfied, as reported in Table II above.

F9 · derivative.expiration_date: Represents previously granted PSUs for which the performance criteria for the three-year performance period from January 1, 2022 through December 31, 2024 have been satisfied, as reported in Table II above.

SEC source: 0000950170-25-002821 · ownership.xml · derivative · entry 7

Apostolou Stephanie L · CIK 0001806249 · Chief Legal&Sus Officer & Sec.

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 314

Underlying: Common Stock · 69 shares

Expires not disclosed

F8 · derivative.exercise_price: The DERs accrued with respect to additional PSUs credited to the reporting person with respect to PSUs granted on January 4, 2022 and January 4, 2023. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

F8 · derivative.exercise_date: The DERs accrued with respect to additional PSUs credited to the reporting person with respect to PSUs granted on January 4, 2022 and January 4, 2023. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

F8 · derivative.expiration_date: The DERs accrued with respect to additional PSUs credited to the reporting person with respect to PSUs granted on January 4, 2022 and January 4, 2023. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

SEC source: 0000950170-25-002821 · ownership.xml · derivative · entry 6

Apostolou Stephanie L · CIK 0001806249 · Chief Legal&Sus Officer & Sec.

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 3,513

Underlying: Common Stock · 1,439 shares

Expires not disclosed

F3 · derivative.exercise_price: Restricted stock units convert into common stock on a one-for-one basis.

F7 · derivative.exercise_date: On January 4, 2023, the reporting person was granted PSUs for which the performance criteria for the two-year performance period from January 1, 2023 through December 31, 2024 have been satisfied. All of the restricted stock units reported here are subject to vesting based on the continued service of the reporting person through January 5, 2026. If the Company's total shareholder return over the three-year period of January 1, 2023 through December 31, 2025 is negative, then the cumulative number of units that may vest for such three-year period will be capped at 150% of the target number.

F7 · derivative.expiration_date: On January 4, 2023, the reporting person was granted PSUs for which the performance criteria for the two-year performance period from January 1, 2023 through December 31, 2024 have been satisfied. All of the restricted stock units reported here are subject to vesting based on the continued service of the reporting person through January 5, 2026. If the Company's total shareholder return over the three-year period of January 1, 2023 through December 31, 2025 is negative, then the cumulative number of units that may vest for such three-year period will be capped at 150% of the target number.

SEC source: 0000950170-25-002821 · ownership.xml · derivative · entry 5

Apostolou Stephanie L · CIK 0001806249 · Chief Legal&Sus Officer & Sec.

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 6,867

Underlying: Common Stock · 2,630 shares

Expires not disclosed

F3 · derivative.exercise_price: Restricted stock units convert into common stock on a one-for-one basis.

F6 · derivative.exercise_date: On January 4, 2022, the reporting person was granted PSUs for which the performance criteria for the three-year performance period from January 1, 2022 through December 31, 2024 have been satisfied.

F6 · derivative.expiration_date: On January 4, 2022, the reporting person was granted PSUs for which the performance criteria for the three-year performance period from January 1, 2022 through December 31, 2024 have been satisfied.

SEC source: 0000950170-25-002821 · ownership.xml · nonDerivative · entry 4

Apostolou Stephanie L · CIK 0001806249 · Chief Legal&Sus Officer & Sec.

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 49,049

F5 · price: Shares surrendered to the issuer by the reporting person as payment for the tax withholding related to the vesting of RSUs and performance share units ("PSUs").

SEC source: 0000950170-25-002821 · ownership.xml · nonDerivative · entry 3

Apostolou Stephanie L · CIK 0001806249 · Chief Legal&Sus Officer & Sec.

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 54,739

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.

F4 · shares: Represents shares acquired upon release of dividend equivalent rights ("DERs"), as reported in Table II, on a one-for-one basis.

F4 · price: Represents shares acquired upon release of dividend equivalent rights ("DERs"), as reported in Table II, on a one-for-one basis.

SEC source: 0000950170-25-002821 · ownership.xml · nonDerivative · entry 2

Apostolou Stephanie L · CIK 0001806249 · Chief Legal&Sus Officer & Sec.

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 54,529

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 · price: Restricted stock units convert into common stock on a one-for-one basis.

SEC source: 0000950170-25-002821 · ownership.xml · nonDerivative · entry 1

Apostolou Stephanie L · CIK 0001806249 · Chief Legal&Sus Officer & Sec.

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 47,662

F1 · security: The reporting person was awarded time-based restricted stock units ("RSUs") on January 3, 2025, which will vest in annual installments of 25 percent over four years.

F2 · balance_after: Includes 495 shares of Koppers Holdings Inc. common stock acquired pursuant to the Koppers Holdings Inc. Employee Stock Purchase Plan on March 28, 2024. These acquisitions were exempt under both Rule 16b-3(c) and Rule 16b-3(d).

SEC source: 0000950170-24-137920 · ownership.xml · derivative · entry 1

Apostolou Stephanie L · CIK 0001806249 · General Counsel & Secretary

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 245

Underlying: Common Stock · 115 shares

Expires not disclosed

F1 · derivative.exercise_price: The dividend equivalent rights ("DERs") accrued with respect to additional time-based and performance-based restricted stock units ("RSUs" and "PSUs", respectively) credited to the reporting person. Of this total, 73 DERs accrued with respect to RSUs granted on January 4, 2021, January 4, 2022, January 4, 2023, and January 4, 2024, and 42 DERs accrued with respect to PSUs granted on January 4, 2022 and January 4, 2023. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

F1 · derivative.exercise_date: The dividend equivalent rights ("DERs") accrued with respect to additional time-based and performance-based restricted stock units ("RSUs" and "PSUs", respectively) credited to the reporting person. Of this total, 73 DERs accrued with respect to RSUs granted on January 4, 2021, January 4, 2022, January 4, 2023, and January 4, 2024, and 42 DERs accrued with respect to PSUs granted on January 4, 2022 and January 4, 2023. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

F1 · derivative.expiration_date: The dividend equivalent rights ("DERs") accrued with respect to additional time-based and performance-based restricted stock units ("RSUs" and "PSUs", respectively) credited to the reporting person. Of this total, 73 DERs accrued with respect to RSUs granted on January 4, 2021, January 4, 2022, January 4, 2023, and January 4, 2024, and 42 DERs accrued with respect to PSUs granted on January 4, 2022 and January 4, 2023. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

SEC source: 0000950170-24-026130 · ownership.xml · derivative · entry 3

Apostolou Stephanie L · CIK 0001806249 · General Counsel & Secretary

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 130

Underlying: Common Stock · 26 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.

F3 · derivative.exercise_price: These DERs were released in connection with the vesting of RSUs granted on March 3, 2020. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

F3 · shares: These DERs were released in connection with the vesting of RSUs granted on March 3, 2020. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

F3 · derivative.exercise_date: These DERs were released in connection with the vesting of RSUs granted on March 3, 2020. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

F3 · derivative.expiration_date: These DERs were released in connection with the vesting of RSUs granted on March 3, 2020. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

SEC source: 0000950170-24-026130 · ownership.xml · nonDerivative · entry 2

Apostolou Stephanie L · CIK 0001806249 · General Counsel & Secretary

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 33,539

F2 · acquired: Shares surrendered to the issuer by the reporting person as payment for the tax withholding related to the vesting of time-based restricted stock units ("RSUs").

SEC source: 0000950170-24-026130 · ownership.xml · nonDerivative · entry 1

Apostolou Stephanie L · CIK 0001806249 · General Counsel & Secretary

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 34,327

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 · shares: Represents shares acquired upon release of dividend equivalent rights ("DERs"), as reported in Table II, on a one-for-one basis.

F1 · price: Represents shares acquired upon release of dividend equivalent rights ("DERs"), as reported in Table II, on a one-for-one basis.

SEC source: 0000950170-24-003149 · ownership.xml · derivative · entry 10

Apostolou Stephanie L · CIK 0001806249 · General Counsel & Secretary

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 156

Underlying: Common Stock · 102 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.

F11 · derivative.exercise_price: These DERs were released in connection with the vesting of RSUs and PSUs granted on January 4, 2021, January 4, 2022, and January 4, 2023. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

F11 · shares: These DERs were released in connection with the vesting of RSUs and PSUs granted on January 4, 2021, January 4, 2022, and January 4, 2023. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

F11 · derivative.exercise_date: These DERs were released in connection with the vesting of RSUs and PSUs granted on January 4, 2021, January 4, 2022, and January 4, 2023. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

F11 · derivative.expiration_date: These DERs were released in connection with the vesting of RSUs and PSUs granted on January 4, 2021, January 4, 2022, and January 4, 2023. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

SEC source: 0000950170-24-003149 · ownership.xml · derivative · entry 9

Apostolou Stephanie L · CIK 0001806249 · General Counsel & Secretary

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 4,760 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.

F3 · derivative.exercise_price: Restricted stock units convert into common stock on a one-for-one basis.

F10 · derivative.exercise_date: Represents previously granted performance share units for which the performance criteria for the three-year performance period from January 1, 2021 through December 31, 2023 have been satisfied, as reported in Table II above.

F10 · derivative.expiration_date: Represents previously granted performance share units for which the performance criteria for the three-year performance period from January 1, 2021 through December 31, 2023 have been satisfied, as reported in Table II above.

SEC source: 0000950170-24-003149 · ownership.xml · nonDerivative · entry 4

Apostolou Stephanie L · CIK 0001806249 · General Counsel & Secretary

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 34,301

F5 · acquired: Shares surrendered to the issuer by the reporting person as payment for the tax withholding related to the vesting of time-based restricted stock units ("RSUs") and performance share units ("PSUs").

SEC source: 0000950170-24-003149 · ownership.xml · nonDerivative · entry 3

Apostolou Stephanie L · CIK 0001806249 · General Counsel & Secretary

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 38,338

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.

F4 · shares: Represents shares acquired upon release of dividend equivalent rights ("DERs"), as reported in Table II, on a one-for-one basis.

F4 · price: Represents shares acquired upon release of dividend equivalent rights ("DERs"), as reported in Table II, on a one-for-one basis.

SEC source: 0000950170-24-003149 · ownership.xml · nonDerivative · entry 2

Apostolou Stephanie L · CIK 0001806249 · General Counsel & Secretary

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 38,236

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 · price: Restricted stock units convert into common stock on a one-for-one basis.

SEC source: 0000950170-24-003149 · ownership.xml · derivative · entry 8

Apostolou Stephanie L · CIK 0001806249 · General Counsel & Secretary

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 258

Underlying: Common Stock · 88 shares

Expires not disclosed

F9 · derivative.exercise_price: The DERs accrued with respect to additional PSUs credited to the reporting person with respect to PSUs granted on January 4, 2021, January 4, 2022, and January 4, 2023. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

F9 · derivative.exercise_date: The DERs accrued with respect to additional PSUs credited to the reporting person with respect to PSUs granted on January 4, 2021, January 4, 2022, and January 4, 2023. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

F9 · derivative.expiration_date: The DERs accrued with respect to additional PSUs credited to the reporting person with respect to PSUs granted on January 4, 2021, January 4, 2022, and January 4, 2023. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

SEC source: 0000950170-24-003149 · ownership.xml · derivative · entry 7

Apostolou Stephanie L · CIK 0001806249 · General Counsel & Secretary

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 2,074

Underlying: Common Stock · 2,074 shares

Expires not disclosed

F3 · derivative.exercise_price: Restricted stock units convert into common stock on a one-for-one basis.

F8 · derivative.exercise_date: On January 4, 2023, the reporting person was granted PSUs for which the performance criteria for the one-year performance period from January 1, 2023 through December 31, 2023 have been satisfied. All of the restricted stock units reported here are subject to vesting based on the continued service of the reporting person through January 5, 2026. If the Company's total shareholder return over the three-year period of January 1, 2023 through December 31, 2025 is negative, then the cumulative number of units that may vest for such three-year period will be capped at 150% of the target number.

F8 · derivative.expiration_date: On January 4, 2023, the reporting person was granted PSUs for which the performance criteria for the one-year performance period from January 1, 2023 through December 31, 2023 have been satisfied. All of the restricted stock units reported here are subject to vesting based on the continued service of the reporting person through January 5, 2026. If the Company's total shareholder return over the three-year period of January 1, 2023 through December 31, 2025 is negative, then the cumulative number of units that may vest for such three-year period will be capped at 150% of the target number.

SEC source: 0000950170-24-003149 · ownership.xml · derivative · entry 6

Apostolou Stephanie L · CIK 0001806249 · General Counsel & Secretary

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 4,237

Underlying: Common Stock · 3,462 shares

Expires not disclosed

F3 · derivative.exercise_price: Restricted stock units convert into common stock on a one-for-one basis.

F7 · derivative.exercise_date: On January 4, 2022, the reporting person was granted PSUs for which the performance criteria for the two-year performance period from January 1, 2022 through December 31, 2023 have been satisfied. All of the restricted stock units reported here are subject to vesting based on the continued service of the reporting person through January 5, 2025. If the Company's total shareholder return over the three-year period of January 1, 2022 through December 31, 2024 is negative, then the cumulative number of units that may vest for such three-year period will be capped at 150% of the target number.

F7 · derivative.expiration_date: On January 4, 2022, the reporting person was granted PSUs for which the performance criteria for the two-year performance period from January 1, 2022 through December 31, 2023 have been satisfied. All of the restricted stock units reported here are subject to vesting based on the continued service of the reporting person through January 5, 2025. If the Company's total shareholder return over the three-year period of January 1, 2022 through December 31, 2024 is negative, then the cumulative number of units that may vest for such three-year period will be capped at 150% of the target number.

SEC source: 0000950170-24-003149 · ownership.xml · derivative · entry 5

Apostolou Stephanie L · CIK 0001806249 · General Counsel & Secretary

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 4,760

Underlying: Common Stock · 2,424 shares

Expires not disclosed

F3 · derivative.exercise_price: Restricted stock units convert into common stock on a one-for-one basis.

F6 · derivative.exercise_date: On January 4, 2021, the reporting person was granted PSUs for which the performance criteria for the three-year performance period from January 1, 2021 through December 31, 2023 have been satisfied.

F6 · derivative.expiration_date: On January 4, 2021, the reporting person was granted PSUs for which the performance criteria for the three-year performance period from January 1, 2021 through December 31, 2023 have been satisfied.

SEC source: 0000950170-24-003149 · ownership.xml · nonDerivative · entry 1

Apostolou Stephanie L · CIK 0001806249 · General Counsel & Secretary

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 33,476

F1 · security: The reporting person was awarded time-based restricted stock units on January 4, 2024, which will vest in annual installments of one-third each over three years.

F2 · balance_after: Includes 809 shares of Koppers Holdings Inc. common stock acquired pursuant to the Koppers Holdings Inc. Employee Stock Purchase Plan on March 31, 2023 and June 30, 2023. These acquisitions were exempt under both Rule 16b-3(c) and Rule 16b-3(d).

SEC source: 0000950170-23-070486 · ownership.xml · derivative · entry 1

Apostolou Stephanie L · CIK 0001806249 · General Counsel & Secretary

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 170

Underlying: Common Stock · 102 shares

Expires not disclosed

F1 · derivative.exercise_price: The dividend equivalent rights ("DERs") accrued with respect to additional time-based and performance-based restricted stock units ("RSUs" and "PSUs", respectively) credited to the reporting person. Of this total, 82 DERs accrued with respect to RSUs granted on March 3, 2020, January 4, 2021, January 4, 2022, and January 4, 2023, and 20 DERs accrued with respect to PSUs granted on January 4, 2021 and January 4, 2022. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

F1 · derivative.exercise_date: The dividend equivalent rights ("DERs") accrued with respect to additional time-based and performance-based restricted stock units ("RSUs" and "PSUs", respectively) credited to the reporting person. Of this total, 82 DERs accrued with respect to RSUs granted on March 3, 2020, January 4, 2021, January 4, 2022, and January 4, 2023, and 20 DERs accrued with respect to PSUs granted on January 4, 2021 and January 4, 2022. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

F1 · derivative.expiration_date: The dividend equivalent rights ("DERs") accrued with respect to additional time-based and performance-based restricted stock units ("RSUs" and "PSUs", respectively) credited to the reporting person. Of this total, 82 DERs accrued with respect to RSUs granted on March 3, 2020, January 4, 2021, January 4, 2022, and January 4, 2023, and 20 DERs accrued with respect to PSUs granted on January 4, 2021 and January 4, 2022. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

SEC source: 0001209191-23-016831 · doc4.xml · derivative · entry 6

Apostolou Stephanie L · CIK 0001806249 · General Counsel & Secretary

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 68

Underlying: Common Stock · 3 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.

F4 · derivative.exercise_price: These DERs were released in connection with the vesting of RSUs granted on March 6, 2019. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

F4 · shares: These DERs were released in connection with the vesting of RSUs granted on March 6, 2019. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

F4 · derivative.exercise_date: These DERs were released in connection with the vesting of RSUs granted on March 6, 2019. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

F4 · derivative.expiration_date: These DERs were released in connection with the vesting of RSUs granted on March 6, 2019. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

SEC source: 0001209191-23-016831 · doc4.xml · nonDerivative · entry 4

Apostolou Stephanie L · CIK 0001806249 · General Counsel & Secretary

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 28,383

F2 · acquired: Shares surrendered to the issuer by the reporting person as payment for the tax withholding related to the vesting of time-based restricted stock units ("RSUs").

SEC source: 0001209191-23-016831 · doc4.xml · nonDerivative · entry 3

Apostolou Stephanie L · CIK 0001806249 · General Counsel & Secretary

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 28,517

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 · shares: Represents shares acquired upon release of dividend equivalent rights ("DERs"), as reported in Table II, on a one-for-one basis.

F1 · price: Represents shares acquired upon release of dividend equivalent rights ("DERs"), as reported in Table II, on a one-for-one basis.

SEC source: 0001209191-23-016831 · doc4.xml · derivative · entry 5

Apostolou Stephanie L · CIK 0001806249 · General Counsel & Secretary

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 71

Underlying: Common Stock · 14 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.

F3 · derivative.exercise_price: These DERs were released in connection with the vesting of RSUs granted on March 3, 2020. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

F3 · shares: These DERs were released in connection with the vesting of RSUs granted on March 3, 2020. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

F3 · derivative.exercise_date: These DERs were released in connection with the vesting of RSUs granted on March 3, 2020. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

F3 · derivative.expiration_date: These DERs were released in connection with the vesting of RSUs granted on March 3, 2020. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

SEC source: 0001209191-23-016831 · doc4.xml · nonDerivative · entry 2

Apostolou Stephanie L · CIK 0001806249 · General Counsel & Secretary

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 28,514

F2 · acquired: Shares surrendered to the issuer by the reporting person as payment for the tax withholding related to the vesting of time-based restricted stock units ("RSUs").

SEC source: 0001209191-23-016831 · doc4.xml · nonDerivative · entry 1

Apostolou Stephanie L · CIK 0001806249 · General Counsel & Secretary

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 29,312

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 · shares: Represents shares acquired upon release of dividend equivalent rights ("DERs"), as reported in Table II, on a one-for-one basis.

F1 · price: Represents shares acquired upon release of dividend equivalent rights ("DERs"), as reported in Table II, on a one-for-one basis.

SEC source: 0001209191-23-002599 · doc4.xml · derivative · entry 6

Apostolou Stephanie L · CIK 0001806249 · General Counsel & Secretary

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 85

Underlying: Common Stock · 11 shares

Expires not disclosed

F7 · derivative.exercise_price: The DERs accrued with respect to additional PSUs credited to the reporting person with respect to PSUs granted on January 4, 2021 and January 4, 2022. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

F7 · derivative.exercise_date: The DERs accrued with respect to additional PSUs credited to the reporting person with respect to PSUs granted on January 4, 2021 and January 4, 2022. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

F7 · derivative.expiration_date: The DERs accrued with respect to additional PSUs credited to the reporting person with respect to PSUs granted on January 4, 2021 and January 4, 2022. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

SEC source: 0001209191-23-002599 · doc4.xml · derivative · entry 5

Apostolou Stephanie L · CIK 0001806249 · General Counsel & Secretary

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 775

Underlying: Common Stock · 775 shares

Expires not disclosed

F4 · derivative.exercise_price: Restricted stock units represent the right to receive shares of common stock on a one-for-one basis and may be settled in cash or in shares of common stock.

F6 · derivative.exercise_date: On January 4, 2022, the reporting person was granted PSUs for which the one-year performance period from January 1, 2022 through December 31, 2022 have been satisfied. All of the restricted stock units reported here are subject to vesting based on the continued service of the reporting person through January 5, 2025. If the Company's total shareholder return over the three-year period of January 1, 2022 through December 31, 2024 is negative, then the cumulative number of units that may vest for such three-year period will be capped at 150% of the target number.

F6 · derivative.expiration_date: On January 4, 2022, the reporting person was granted PSUs for which the one-year performance period from January 1, 2022 through December 31, 2022 have been satisfied. All of the restricted stock units reported here are subject to vesting based on the continued service of the reporting person through January 5, 2025. If the Company's total shareholder return over the three-year period of January 1, 2022 through December 31, 2024 is negative, then the cumulative number of units that may vest for such three-year period will be capped at 150% of the target number.

SEC source: 0001209191-23-002599 · doc4.xml · derivative · entry 4

Apostolou Stephanie L · CIK 0001806249 · General Counsel & Secretary

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 2,336

Underlying: Common Stock · 931 shares

Expires not disclosed

F4 · derivative.exercise_price: Restricted stock units represent the right to receive shares of common stock on a one-for-one basis and may be settled in cash or in shares of common stock.

F5 · derivative.exercise_date: On January 4, 2021, the reporting person was granted performance share units ("PSUs") for which the two-year performance period from January 1, 2021 through December 31, 2022 have been satisfied. All of the restricted stock units reported here are subject to vesting based on the continued service of the reporting person through January 5, 2024. If the Company's total shareholder return over the three-year period of January 1, 2021 through December 31, 2023 is negative, then the cumulative number of units that may vest for such three-year period will be capped at 150% of the target number.

F5 · derivative.expiration_date: On January 4, 2021, the reporting person was granted performance share units ("PSUs") for which the two-year performance period from January 1, 2021 through December 31, 2022 have been satisfied. All of the restricted stock units reported here are subject to vesting based on the continued service of the reporting person through January 5, 2024. If the Company's total shareholder return over the three-year period of January 1, 2021 through December 31, 2023 is negative, then the cumulative number of units that may vest for such three-year period will be capped at 150% of the target number.

SEC source: 0001209191-23-002599 · doc4.xml · derivative · entry 3

Apostolou Stephanie L · CIK 0001806249 · General Counsel & Secretary

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 74

Underlying: Common Stock · 14 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.

F3 · derivative.exercise_price: These DERs were released in connection with the vesting of RSUs granted on January 4, 2021 and January 4, 2022. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

F3 · shares: These DERs were released in connection with the vesting of RSUs granted on January 4, 2021 and January 4, 2022. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

F3 · derivative.exercise_date: These DERs were released in connection with the vesting of RSUs granted on January 4, 2021 and January 4, 2022. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

F3 · derivative.expiration_date: These DERs were released in connection with the vesting of RSUs granted on January 4, 2021 and January 4, 2022. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

SEC source: 0001209191-23-002599 · doc4.xml · nonDerivative · entry 2

Apostolou Stephanie L · CIK 0001806249 · General Counsel & Secretary

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 29,298.8708

F2 · acquired: Shares surrendered to the issuer by the reporting person as payment for the tax withholding related to the vesting of time-based restricted stock units ("RSUs").