X0407 4 2023-05-15 0 0001819928 DoubleVerify Holdings, Inc. DV 0001854079 Grimmig Andrew E C/O DOUBLEVERIFY HOLDINGS, INC. 462 BROADWAY NEW YORK NY 10013 0 1 0 0 Chief Legal Officer 1 Common Stock 2023-05-15 4 M 0 40000 6.45 A 95964 D Common Stock 2023-05-15 4 S 0 40000 27.9954 D 55964 D Common Stock 2023-05-15 4 M 0 1983 0.00 A 57947 D Common Stock 2023-05-15 4 F 0 958 28.37 D 56989 D Options (Rights to Buy) 6.45 2023-05-15 4 M 0 40000 0.00 D 2030-04-27 Common Stock 40000 321174 D Restricted Stock Units 2023-05-15 4 M 0 1983 0.00 D Common Stock 1983 13879 D The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on December 22, 2022. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions ranging from $27.78 to $28.29, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth above. Each restricted stock unit ("RSU") was granted on February 17, 2021 and represents a right to receive one share of common stock on a one-to-one basis. 25% of the RSUs vested and were settled on February 15, 2022, and the other remaining RSUs have continued, and will continue, to vest at a rate of 6.25% per quarter thereafter, subject to Mr. Grimmig's continued employment through the applicable vesting date. Represents shares withheld to satisfy tax obligations in connection with the vesting of 1,983 RSUs on May 15, 2023. Represents non-qualified stock options granted on April 27, 2020, 25% of which vested on March 30, 2021 and the remainder of which vest at a rate of 6.25% per quarter thereafter, subject to Mr. Grimmig's continued employment. RSUs convert into common stock on a one-for-one basis. /s/ Andrew E. Grimmig 2023-05-17