144 0001776456 XXXXXXXX LIVE 0000075677 PACKAGING CORPORATION OF AMERICA 001-15399 1 North Field Court Lake Forest IL 60045 847-482-3000 Bruce A. Ridley Officer Common Woodbury Financial

7755 3rd Street N Oakdale MN 55128

3493 542183.46 89932185 08/02/2023 NYSE Common 06/28/2023 restricted stock vesting under a registered plan issuer N 1967 06/28/2023 services rendered common 06/26/2022 restricted stock vesting under a registered plan issuer N 1526 06/26/2022 services rendered Y 08/07/2023 /s/ Bruce A. Ridley