KOP

SEC source: 0000950170-25-045377 · ownership.xml · derivative · entry 2

Feng Xudong · CIK 0001463649 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 201.027

Underlying: Common Stock · 27.244 shares

Expires not disclosed

F3 · derivative.exercise_price: The DERs accrued with respect to additional RSUs credited to the reporting person with respect to deferred compensation. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

F2 · derivative.exercise_date: Once released, the RSUs corresponding to these DERs will become payable according to the election of payment designation that was filed by the reporting person subject to the Koppers Holdings Inc. Director Deferred Compensation Plan (the "Plan"). Such payment will be either lump sum or in annual installments commencing on the May 31st next following the reporting person's separation from service (as defined under the Plan) or, if later, and elected by the reporting person at the time he/she first elects to defer any payment under the Plan, May 31st of the year specified by the reporting person.

F2 · derivative.expiration_date: Once released, the RSUs corresponding to these DERs will become payable according to the election of payment designation that was filed by the reporting person subject to the Koppers Holdings Inc. Director Deferred Compensation Plan (the "Plan"). Such payment will be either lump sum or in annual installments commencing on the May 31st next following the reporting person's separation from service (as defined under the Plan) or, if later, and elected by the reporting person at the time he/she first elects to defer any payment under the Plan, May 31st of the year specified by the reporting person.

SEC source: 0000950170-25-045377 · ownership.xml · derivative · entry 1

Feng Xudong · CIK 0001463649 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 173.783

Underlying: Common Stock · 17 shares

Expires not disclosed

F1 · derivative.exercise_price: The dividend equivalent rights ("DERs") accrued with respect to additional time-based restricted stock units ("RSUs") credited to the reporting person with respect to RSUs granted on May 2, 2024. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

F2 · derivative.exercise_date: Once released, the RSUs corresponding to these DERs will become payable according to the election of payment designation that was filed by the reporting person subject to the Koppers Holdings Inc. Director Deferred Compensation Plan (the "Plan"). Such payment will be either lump sum or in annual installments commencing on the May 31st next following the reporting person's separation from service (as defined under the Plan) or, if later, and elected by the reporting person at the time he/she first elects to defer any payment under the Plan, May 31st of the year specified by the reporting person.

F2 · derivative.expiration_date: Once released, the RSUs corresponding to these DERs will become payable according to the election of payment designation that was filed by the reporting person subject to the Koppers Holdings Inc. Director Deferred Compensation Plan (the "Plan"). Such payment will be either lump sum or in annual installments commencing on the May 31st next following the reporting person's separation from service (as defined under the Plan) or, if later, and elected by the reporting person at the time he/she first elects to defer any payment under the Plan, May 31st of the year specified by the reporting person.

SEC source: 0000950170-25-045267 · ownership.xml · derivative · entry 1

Tritch Stephen R · CIK 0001463204 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 17

Underlying: Common Stock · 17 shares

Expires not disclosed

F1 · derivative.exercise_price: The dividend equivalent rights ("DERs") accrued with respect to additional time-based restricted stock units ("RSUs") credited to the reporting person with respect to RSUs granted on May 2, 2024. 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 restricted stock units ("RSUs") credited to the reporting person with respect to RSUs granted on May 2, 2024. 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 restricted stock units ("RSUs") credited to the reporting person with respect to RSUs granted on May 2, 2024. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

SEC source: 0000950170-25-045258 · ownership.xml · derivative · entry 2

WILKERSON SONJA MICHELLE · CIK 0001245155 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 168.036

Underlying: Common Stock · 22.202 shares

Expires not disclosed

F4 · derivative.exercise_price: The DERs accrued with respect to additional RSUs credited to the reporting person with respect to deferred compensation. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

F2 · derivative.exercise_date: Once released, the RSUs corresponding to these DERs will become payable according to the election of payment designation that was filed by the reporting person subject to the Koppers Holdings Inc. Director Deferred Compensation Plan (the "Plan"). Such payment will be either lump sum or in annual installments commencing on the May 31st next following the reporting person's separation from service (as defined under the Plan) or, if later, and elected by the reporting person at the time he/she first elects to defer any payment under the Plan, May 31st of the year specified by the reporting person.

F2 · derivative.expiration_date: Once released, the RSUs corresponding to these DERs will become payable according to the election of payment designation that was filed by the reporting person subject to the Koppers Holdings Inc. Director Deferred Compensation Plan (the "Plan"). Such payment will be either lump sum or in annual installments commencing on the May 31st next following the reporting person's separation from service (as defined under the Plan) or, if later, and elected by the reporting person at the time he/she first elects to defer any payment under the Plan, May 31st of the year specified by the reporting person.

SEC source: 0000950170-25-045258 · ownership.xml · derivative · entry 1

WILKERSON SONJA MICHELLE · CIK 0001245155 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 145.834

Underlying: Common Stock · 17 shares

Expires not disclosed

F1 · derivative.exercise_price: The dividend equivalent rights ("DERs") accrued with respect to additional time-based restricted stock units ("RSUs") credited to the reporting person with respect to RSUs granted on May 2, 2024. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

F2 · derivative.exercise_date: Once released, the RSUs corresponding to these DERs will become payable according to the election of payment designation that was filed by the reporting person subject to the Koppers Holdings Inc. Director Deferred Compensation Plan (the "Plan"). Such payment will be either lump sum or in annual installments commencing on the May 31st next following the reporting person's separation from service (as defined under the Plan) or, if later, and elected by the reporting person at the time he/she first elects to defer any payment under the Plan, May 31st of the year specified by the reporting person.

F2 · derivative.expiration_date: Once released, the RSUs corresponding to these DERs will become payable according to the election of payment designation that was filed by the reporting person subject to the Koppers Holdings Inc. Director Deferred Compensation Plan (the "Plan"). Such payment will be either lump sum or in annual installments commencing on the May 31st next following the reporting person's separation from service (as defined under the Plan) or, if later, and elected by the reporting person at the time he/she first elects to defer any payment under the Plan, May 31st of the year specified by the reporting person.

F3 · balance_after: Includes 0.80 DERs that inadvertently were not previously reported.

SEC source: 0000950170-25-045324 · ownership.xml · derivative · entry 1

NEUPAVER ALBERT J · CIK 0001190210 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 17

Underlying: Common Stock · 17 shares

Expires not disclosed

F1 · derivative.exercise_price: The dividend equivalent rights ("DERs") accrued with respect to additional time-based restricted stock units ("RSUs") credited to the reporting person with respect to RSUs granted on May 2, 2024. 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 restricted stock units ("RSUs") credited to the reporting person with respect to RSUs granted on May 2, 2024. 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 restricted stock units ("RSUs") credited to the reporting person with respect to RSUs granted on May 2, 2024. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

SEC source: 0000950170-25-045416 · ownership.xml · derivative · entry 1

Washington Kevin · CIK 0001932214 · VP, External Relations

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 60

Underlying: Common Stock · 4 shares

Expires not disclosed

F1 · derivative.exercise_price: The dividend equivalent rights ("DERs") accrued with respect to additional time-based restricted stock units ("RSUs") credited to the reporting person with respect to RSUs granted on June 13, 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 restricted stock units ("RSUs") credited to the reporting person with respect to RSUs granted on June 13, 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 restricted stock units ("RSUs") credited to the reporting person with respect to RSUs granted on June 13, 2022. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

SEC source: 0000950170-25-045434 · ownership.xml · derivative · entry 1

Vartanian Nishan J. · CIK 0001564614 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 17

Underlying: Common Stock · 17 shares

Expires not disclosed

F1 · derivative.exercise_price: The dividend equivalent rights ("DERs") accrued with respect to additional time-based restricted stock units ("RSUs") credited to the reporting person with respect to RSUs granted on May 2, 2024. 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 restricted stock units ("RSUs") credited to the reporting person with respect to RSUs granted on May 2, 2024. 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 restricted stock units ("RSUs") credited to the reporting person with respect to RSUs granted on May 2, 2024. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

SEC source: 0000950170-25-045388 · ownership.xml · derivative · entry 1

Lucas Stephen G · CIK 0001919175 · SVP, Culture and Engagement

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 205

Underlying: Common Stock · 18 shares

Expires not disclosed

F1 · derivative.exercise_price: The dividend equivalent rights ("DERs") accrued with respect to additional time-based restricted stock units ("RSUs") credited to the reporting person with respect to RSUs granted on April 11, 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 restricted stock units ("RSUs") credited to the reporting person with respect to RSUs granted on April 11, 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 restricted stock units ("RSUs") credited to the reporting person with respect to RSUs granted on April 11, 2022. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

SEC source: 0000950170-25-045361 · ownership.xml · derivative · entry 1

JENSEN TRACI L · CIK 0001533627 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 17

Underlying: Common Stock · 17 shares

Expires not disclosed

F1 · derivative.exercise_price: The dividend equivalent rights ("DERs") accrued with respect to additional time-based restricted stock units ("RSUs") credited to the reporting person with respect to RSUs granted on May 2, 2024. 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 restricted stock units ("RSUs") credited to the reporting person with respect to RSUs granted on May 2, 2024. 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 restricted stock units ("RSUs") credited to the reporting person with respect to RSUs granted on May 2, 2024. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

SEC source: 0000950170-25-045346 · ownership.xml · derivative · entry 2

MOTLEY DAVID L · CIK 0001584601 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 168.036

Underlying: Common Stock · 22.202 shares

Expires not disclosed

F3 · derivative.exercise_price: The DERs accrued with respect to additional RSUs credited to the reporting person with respect to deferred compensation. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

F2 · derivative.exercise_date: Once released, the RSUs corresponding to these DERs will become payable according to the election of payment designation that was filed by the reporting person subject to the Koppers Holdings Inc. Director Deferred Compensation Plan (the "Plan"). Such payment will be either lump sum or in annual installments commencing on the May 31st next following the reporting person's separation from service (as defined under the Plan) or, if later, and elected by the reporting person at the time he/she first elects to defer any payment under the Plan, May 31st of the year specified by the reporting person.

F2 · derivative.expiration_date: Once released, the RSUs corresponding to these DERs will become payable according to the election of payment designation that was filed by the reporting person subject to the Koppers Holdings Inc. Director Deferred Compensation Plan (the "Plan"). Such payment will be either lump sum or in annual installments commencing on the May 31st next following the reporting person's separation from service (as defined under the Plan) or, if later, and elected by the reporting person at the time he/she first elects to defer any payment under the Plan, May 31st of the year specified by the reporting person.

SEC source: 0000950170-25-045346 · ownership.xml · derivative · entry 1

MOTLEY DAVID L · CIK 0001584601 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 145.834

Underlying: Common Stock · 17 shares

Expires not disclosed

F1 · derivative.exercise_price: The dividend equivalent rights ("DERs") accrued with respect to additional time-based restricted stock units ("RSUs") credited to the reporting person with respect to RSUs granted on May 2, 2024. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

F2 · derivative.exercise_date: Once released, the RSUs corresponding to these DERs will become payable according to the election of payment designation that was filed by the reporting person subject to the Koppers Holdings Inc. Director Deferred Compensation Plan (the "Plan"). Such payment will be either lump sum or in annual installments commencing on the May 31st next following the reporting person's separation from service (as defined under the Plan) or, if later, and elected by the reporting person at the time he/she first elects to defer any payment under the Plan, May 31st of the year specified by the reporting person.

F2 · derivative.expiration_date: Once released, the RSUs corresponding to these DERs will become payable according to the election of payment designation that was filed by the reporting person subject to the Koppers Holdings Inc. Director Deferred Compensation Plan (the "Plan"). Such payment will be either lump sum or in annual installments commencing on the May 31st next following the reporting person's separation from service (as defined under the Plan) or, if later, and elected by the reporting person at the time he/she first elects to defer any payment under the Plan, May 31st of the year specified by the reporting person.

SEC source: 0000950170-25-045305 · ownership.xml · derivative · entry 1

TESTONI LOUIS L · CIK 0001576713 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 17

Underlying: Common Stock · 17 shares

Expires not disclosed

F1 · derivative.exercise_price: The dividend equivalent rights ("DERs") accrued with respect to additional time-based restricted stock units ("RSUs") credited to the reporting person with respect to RSUs granted on May 2, 2024. 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 restricted stock units ("RSUs") credited to the reporting person with respect to RSUs granted on May 2, 2024. 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 restricted stock units ("RSUs") credited to the reporting person with respect to RSUs granted on May 2, 2024. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

SEC source: 0000950170-25-042667 · ownership.xml · nonDerivative · entry 2

BALL M LEROY · CIK 0001229771 · Director · CEO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 361,512.4007

F2 · price: The price reported in column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $29.94 to $30.33, inclusive. The reporting person undertakes to provide to the Securities and Exchange Commission, the issuer or any security holder of the issuer, upon request, full information regarding the number of shares sold at each separate price.

SEC source: 0000950170-25-042667 · ownership.xml · nonDerivative · entry 1

BALL M LEROY · CIK 0001229771 · Director · CEO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 362,017.4007

F1 · price: The price reported in column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $28.55 to $29.50, inclusive. The reporting person undertakes to provide to the Securities and Exchange Commission, the issuer or any security holder of the issuer, upon request, full information regarding the number of shares sold at each separate price.

SEC source: 0000950170-25-037432 · ownership.xml · derivative · entry 4

WILKERSON SONJA MICHELLE · CIK 0001245155 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 128.34

Underlying: Common Stock · 20.219 shares

Expires not disclosed

F7 · derivative.exercise_price: The DERs accrued with respect to additional time-based RSUs credited to the reporting person with respect to deferred compensation. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

F4 · derivative.exercise_date: Once released, the RSUs corresponding to these dividend equivalent rights ("DERs") will become payable according to the election of payment designation that was filed by the reporting person subject to the Plan. Such payment will be either lump sum or in annual installments commencing on the May 31st next following the reporting person's separation from service (as defined under the Plan) or, if later, and elected by the reporting person at the time he/she first elects to defer any payment under the Plan, May 31st of the year specified by the reporting person.

F4 · derivative.expiration_date: Once released, the RSUs corresponding to these dividend equivalent rights ("DERs") will become payable according to the election of payment designation that was filed by the reporting person subject to the Plan. Such payment will be either lump sum or in annual installments commencing on the May 31st next following the reporting person's separation from service (as defined under the Plan) or, if later, and elected by the reporting person at the time he/she first elects to defer any payment under the Plan, May 31st of the year specified by the reporting person.

SEC source: 0000950170-25-037432 · ownership.xml · nonDerivative · entry 1

WILKERSON SONJA MICHELLE · CIK 0001245155 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 17,216

F1 · kind: As disclosed in this Form 4 amendment, the reporting person inadvertently reported 3,513 RSUs and 20 DERs in Table I in the reporting person's previously-filed Forms 4. In fact, as reported in this amendment, the reporting person directly owns 17,216 shares of common stock.

F1 · shares: As disclosed in this Form 4 amendment, the reporting person inadvertently reported 3,513 RSUs and 20 DERs in Table I in the reporting person's previously-filed Forms 4. In fact, as reported in this amendment, the reporting person directly owns 17,216 shares of common stock.

F1 · price: As disclosed in this Form 4 amendment, the reporting person inadvertently reported 3,513 RSUs and 20 DERs in Table I in the reporting person's previously-filed Forms 4. In fact, as reported in this amendment, the reporting person directly owns 17,216 shares of common stock.

F1 · balance_after: As disclosed in this Form 4 amendment, the reporting person inadvertently reported 3,513 RSUs and 20 DERs in Table I in the reporting person's previously-filed Forms 4. In fact, as reported in this amendment, the reporting person directly owns 17,216 shares of common stock.

SEC source: 0000950170-25-025718 · ownership.xml · derivative · entry 3

BALL M LEROY · CIK 0001229771 · Director · CEO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 6,000 shares

Expires 2025-03-03

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_date: Stock options vested in annual installments of 25 percent over 4 years.

SEC source: 0000950170-25-025718 · ownership.xml · nonDerivative · entry 2

BALL M LEROY · CIK 0001229771 · Director · CEO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 365,296.4007

SEC source: 0000950170-25-025718 · ownership.xml · nonDerivative · entry 1

BALL M LEROY · CIK 0001229771 · Director · CEO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 369,798.4007

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: 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: 0000950170-25-002809 · ownership.xml · derivative · entry 8

Pearce Bradley A · CIK 0001776180 · Chief Accounting Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 55

Underlying: Common Stock · 106 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.

F8 · 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.

F8 · 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.

F8 · 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.

F8 · 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: 0000950170-25-002809 · ownership.xml · derivative · entry 7

Pearce Bradley A · CIK 0001776180 · Chief Accounting Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 1,748 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.

F2 · derivative.exercise_price: Restricted stock units convert into common stock on a one-for-one basis.

F7 · 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.

F7 · 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: 0000950170-25-002809 · ownership.xml · derivative · entry 6

Pearce Bradley A · CIK 0001776180 · Chief Accounting Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 161

Underlying: Common Stock · 12 shares

Expires not disclosed

F6 · 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. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

F6 · 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. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

F6 · 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. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

SEC source: 0000950170-25-002809 · ownership.xml · derivative · entry 5

Pearce Bradley A · CIK 0001776180 · Chief Accounting Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 1,748

Underlying: Common Stock · 669 shares

Expires not disclosed

F2 · derivative.exercise_price: Restricted stock units convert into common stock on a one-for-one basis.

F5 · 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.

F5 · 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: 0000950170-25-002809 · ownership.xml · nonDerivative · entry 4

Pearce Bradley A · CIK 0001776180 · Chief Accounting Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 31,184

F4 · 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: 0000950170-25-002809 · ownership.xml · nonDerivative · entry 3

Pearce Bradley A · CIK 0001776180 · Chief Accounting Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 34,336

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

F3 · price: Represents shares acquired upon release of dividend equivalent rights ("DERs"), as reported in Table II, on a one-for-one basis.

SEC source: 0000950170-25-002809 · ownership.xml · nonDerivative · entry 2

Pearce Bradley A · CIK 0001776180 · Chief Accounting Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 34,230

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

SEC source: 0000950170-25-002809 · ownership.xml · nonDerivative · entry 1

Pearce Bradley A · CIK 0001776180 · Chief Accounting Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 32,482

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.

SEC source: 0000950170-25-002802 · ownership.xml · derivative · entry 9

Smith Jimmi Sue · CIK 0001684691 · Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 106

Underlying: Common Stock · 234 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: 0000950170-25-002802 · ownership.xml · derivative · entry 8

Smith Jimmi Sue · CIK 0001684691 · Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 7,802 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: 0000950170-25-002802 · ownership.xml · derivative · entry 7

Smith Jimmi Sue · CIK 0001684691 · Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 340

Underlying: Common Stock · 78 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: 0000950170-25-002802 · ownership.xml · derivative · entry 6

Smith Jimmi Sue · CIK 0001684691 · Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 3,659

Underlying: Common Stock · 1,499 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: 0000950170-25-002802 · ownership.xml · derivative · entry 5

Smith Jimmi Sue · CIK 0001684691 · Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 7,802

Underlying: Common Stock · 2,987 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: 0000950170-25-002802 · ownership.xml · nonDerivative · entry 4

Smith Jimmi Sue · CIK 0001684691 · Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 40,854

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: 0000950170-25-002802 · ownership.xml · nonDerivative · entry 3

Smith Jimmi Sue · CIK 0001684691 · Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 47,059

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: 0000950170-25-002802 · ownership.xml · nonDerivative · entry 2

Smith Jimmi Sue · CIK 0001684691 · Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 46,825

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: 0000950170-25-002802 · ownership.xml · nonDerivative · entry 1

Smith Jimmi Sue · CIK 0001684691 · Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 39,023

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 478 shares of Koppers Holdings Inc. common stock acquired pursuant to the Koppers Holdings Inc. Employee Stock Purchase Plan on March 28, 2024, June 28, 2024, and September 30, 2024. These acquisitions were exempt under both Rule 16b-3(c) and Rule 16b-3(d).

SEC source: 0000950170-25-002800 · ownership.xml · derivative · entry 9

Sullivan James A. · CIK 0001450800 · President and COO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 287

Underlying: Common Stock · 523 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.

F9 · 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.

F9 · 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.

F9 · 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.

F9 · 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: 0000950170-25-002800 · ownership.xml · derivative · entry 8

Sullivan James A. · CIK 0001450800 · President and COO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 17,146 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.

F2 · derivative.exercise_price: Restricted stock units convert into common stock on a one-for-one basis.

F8 · 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.

F8 · 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: 0000950170-25-002800 · ownership.xml · derivative · entry 7

Sullivan James A. · CIK 0001450800 · President and COO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 810

Underlying: Common Stock · 182 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, 2022 and January 4, 2023. 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, 2022 and January 4, 2023. 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, 2022 and January 4, 2023. Each DER is the economic equivalent of one share of Koppers Holdings Inc. common stock.

SEC source: 0000950170-25-002800 · ownership.xml · derivative · entry 6

Sullivan James A. · CIK 0001450800 · President and COO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 9,368

Underlying: Common Stock · 3,838 shares

Expires not disclosed

F2 · 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 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.

F6 · 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.