SCHEDULE 13G/A

INTEGRAL AD SCIENCE HLDNG CO

Common Stock, $0.001 · CUSIP: 45828L108

Event date: 2025-12-23

Reporting persons may disclose overlapping interests. Their amounts are shown individually and are not added into a filing total.

Filing-level shares

Unavailable

Percent of class

Unavailable

• Atlas Venture Fund VIII, L.P.

  Shares: 0.00 · Class: 0.0%

• Atlas Venture Associates VIII, L.P.

  Shares: 0.00 · Class: 0.0%

• Atlas Venture Associates VIII, Inc.

  Shares: 0.00 · Class: 0.0%

Amounts are as disclosed in this filing. Schedule type alone does not establish investment intent.