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      <sellerDetails>
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    <remarks>Tom Sharma and Kshitij Sharma are one and the same person</remarks>
    <noticeSignature>
      <noticeDate>05/23/2023</noticeDate>
      <signature>/s/ Daniel Tucci, as a duly authorized representative of Fidelity Brokerage Services LLC, as attorney-in-fact for Kshitij Sharma</signature>
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144
0001861730
XXXXXXXX
LIVE
0001842718
INTEGRAL AD SCIENCE HOLDING CORP.
001-40557
99 WALL STREET
#1950
NEW YORK
NY
10005
(646) 278-4871
SHARMA TOM
Officer
Common
Fidelity Brokerage Services LLC
900 Salem Street
Smithfield
RI
02917
13452
237718.36
154927770
05/23/2023
NASDAQ
Common
05/19/2023
Restricted Stock Vesting
Issuer
N
13452
05/19/2023
Compensation
N
Kshitij Sharma
99 Wall Street, #1950
New York
NY
10005
Common
03/21/2023
4200
58802.10
Kshitij Sharma
99 Wall Street, #1950
New York
NY
10005
Common
03/22/2023
28385
397920.80
Kshitij Sharma
99 Wall Street, #1950
New York
NY
10005
Common
03/23/2023
9956
139902.71
Kshitij Sharma
99 Wall Street, #1950
New York
NY
10005
Common
03/24/2023
13243
185437.76
Kshitij Sharma
99 Wall Street, #1950
New York
NY
10005
Common
03/31/2023
17115
241862.33
Kshitij Sharma
99 Wall Street
#1950
New York
NY
10005
Common
04/27/2023
9204
147264.00
Kshitij Sharma
99 Wall Street
#1950
New York
NY
10005
Common
05/01/2023
4492
71873.80
Kshitij Sharma
99 Wall Street
#1950
New York
NY
10005
Common
05/02/2023
1500
24007.05
Kshitij Sharma
99 Wall Street
#1950
New York
NY
10005
Common
05/04/2023
4157
66512.00
Kshitij Sharma
99 Wall Street
#1950
New York
NY
10005
Common
05/05/2023
53546
899015.92
Kshitij Sharma
99 Wall Street
#1950
New York
NY
10005
Common
05/22/2023
9646
167887.67
Tom Sharma and Kshitij Sharma are one and the same person
05/23/2023
/s/ Daniel Tucci, as a duly authorized representative of Fidelity Brokerage Services LLC, as attorney-in-fact for Kshitij Sharma