Transaction Details

Footnotes

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. | This Form 4 amendment is being filed to correct the transaction date. | Represents shares acquired upon release of dividend equivalent rights ("DERs"), as reported in Table II, on a one-for-one basis. | Shares surrendered to the issuer by the reporting person as payment for the tax withholding related to the vesting of PSUs. | 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. | 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.