Form 4 Filing for Lord Robert regarding Integral Ad Science Holding Corp.

Lord Robert, a director at Integral Ad Science Holding Corp. (IAS), reported a disposition of 29,184 shares of common stock on December 23, 2025, at a price of $10.30 per share. This transaction was executed as part of a merger agreement where the company merged with Igloo Group Parent, Inc. The disposition includes 17,637 unvested restricted stock units that were fully vested and cancelled at the time of the merger, converted into the right to receive cash. Following the transaction, Lord Robert holds 0 shares of common stock. This filing is made on Form 4.