144 0001955607 XXXXXXXX LIVE 0001842718 INTEGRAL AD SCIENCE HOLDING CORP. 001-40557 99 WALL STREET #1950 NEW YORK NY 10005 (646) 278-4871 SECOR TANIA Former Officer Common Fidelity Brokerage Services LLC

900 Salem Street Smithfield RI 02917

5940 57900.74 162670447 01/07/2025 NASDAQ Common 01/03/2025 Restricted Stock Vesting Issuer N 5940 01/03/2025 Compensation N Tania R. Secor

12 E 49th Street, 20th Floor New York, NY 10017

Common 10/07/2024 5240 52970.11 Tania R. Secor

12 E 49th Street, 20th Floor, New York NY 10017

Common 10/25/2024 22613 277045.25 Tania R. Secor

12 E 49th Street, 20th Floor New York, NY 10017

Common 12/06/2024 6450 70654.59 Tania R. Secor

12 E 49th Street, 20th Floor, New York NY 10017

Common 12/09/2024 7504 80552.44 Sale includes an amount necessary to cover a tax obligation resulting from the settlement of a vested equity award distribution. 01/07/2025 /s/ Gary Redman, as a duly authorized representative of Fidelity Brokerage Services LLC, as attorney-in-fact for Tania R. Secor