X0508 4 2025-08-04 0000094049 STEPAN CO SCL 0001229289 STEPAN F QUINN JR 1101 SKOKIE BOULEVARD, SUITE 500 NORTHBROOK IL 60062 1 0 Common Stock 2025-08-04 4 G 0 2.281 A 105448.019 D Common Stock 2025-08-04 4 F 0 0.615 49.83 D 105447.404 D Common Stock 2025-08-04 4 G 0 3000 0 D 163123 D Common Stock 2025-08-04 4 S 0 6300 49.962 D 166123 D Common Stock 2025-08-05 4 S 0 3700 50.489 D 159423 D Common Stock 0.002 I By Esop II Trust Common Stock 160000 I By Family LLC Common Stock 87500 I By Family Trust IV Common Stock 100 I By Father Common Stock 1017 I By Spouse Common Stock 67.214 I By Father's ESOP Common Stock 19052 I By Family Trust V Common Stock 161869 I By Mother's Estate Common Stock 600 I By Family Trust VI Share Units Common Stock 63404.923 63404.923 D Share Units 2025-08-04 4 M 0 2.281 D Common Stock 2.281 43166.868 I By Father's Deferred MIP Each share unit was the economic equivalent of one share of Stepan Company common stock. On March 10, 2025, 2.281 share units were settled for an equal number of shares of Stepan Company common stock and distributed to the reporting person as beneficiary. Withholding of shares to satisfy the tax liability on the distribution of share units. Joint Tenancy with Spouse. The price reported is a weighted average price. Shares were sold in a series of transactions within the same trading day at prices ranging from $49.75 to $50.26, inclusive. Full information regarding the number of shares sold at each separate price is available upon request by the Commission staff, the issuer, or a security holder of the issuer. The price reported is a weighted average price. Shares were sold in a series of transactions within the same trading day at prices ranging from $49.9897 to $50.9249, inclusive. Full information regarding the number of shares sold at each separate price is available upon request by the Commission staff, the issuer, or a security holder of the issuer. Reflects a downward adjustment of 2,500 shares. Due to administrative error, the reporting person's Form 4 filed on May 13, 2025 included the May 12, 2025 award of 2,500 shares to the reporting person in both the reporting person's individual account total and the reporting person's joint account total. The reporting person disclaims beneficial ownership of these securities, except to extent of any pecuniary interest in the shares. Shares held by an estate of which the reporting person serves as executor. Share Units are acquired under the Management Incentive Plan ("MIP"), a nonqualified deferred compensation plan that allows participants to defer all or a portion of their annual incentive awards. Share Units convert on a one-for-one basis into Common Stock. Share Units are generally payable at end of employment, unless otherwise elected. /s/ Stephanie J. Pacitti, Attorney-in-Fact for F. Quinn Stepan, Jr. 2025-08-06