X0508 4 2023-09-14 0 0001861795 Definitive Healthcare Corp. DH 0001879507 Krantz Jason Ronald C/O DEFINITIVE HEALTHCARE CORP. 492 OLD CONNECTICUT PATH, SUITE 401 FRAMINGHAM MA 01701 1 0 1 1 Executive Chairman 0 Class A common stock 2023-09-14 4 F 0 2649 8.27 D 416753 D Class A common stock 450000 I See footnote The transaction reported represents the withholding of shares by the issuer to satisfy the reporting person's tax withholding obligations in connection with the vesting and settlement of previously reported restricted stock units. Amount beneficially owned in trust by DH Holdings (fka Jason R. Krantz 2009 Trust), of which the reporting person is the beneficiary. /s/ Matthew Ruderman, as attorney in fact 2023-09-18