X0508 4/A 2024-02-15 2024-02-20 0000094049 STEPAN CO SCL 0001780101 Keiper Jason Scott 1101 SKOKIE BOULEVARD, SUITE 500 NORTHBROOK IL 60062 1 VP & Chief Tech & Sust Officer 0 Common Stock 2024-02-15 4 M 0 662 A 6730.5189 D This Form 4/A corrects the number of shares received as a result of performance shares vesting. The number of shares reported on the reporting person's Form 4 filed on February 20, 2024 was miscalculated due to an administrative error. Each performance share represents a contingent right to receive one share of Stepan Company common stock. The performance shares vested upon the certification of Stepan Company achieving certain performance goals for the performance period ending December 31, 2023. /s/ Stephanie J. Pacitti, Attorney-in-Fact for Jason Scott Keiper 2024-03-08