X0306 4 2021-02-16 0 0001315257 Koppers Holdings Inc. KOP 0001806249 Apostolou Stephanie L 436 SEVENTH AVENUE PITTSBURGH PA 15219 0 1 0 0 General Counsel & Secretary Restricted Stock Units 2021-02-16 4 A 0 1282 0.00 A Common Stock 1282 1282 D 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. On March 6, 2019, the reporting person was granted performance share units for which the performance criteria for the two-year performance period from January 1, 2019 through December 31, 2020 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 March 6, 2022. If the Company's total shareholder return over the three-year period of January 1, 2019 through December 31, 2021 is negative, then the cumulative number of units that may vest for such three-year period will be capped at 100% of the target number. /s/Stephanie L. Apostolou 2021-02-18