SCHEDULE 13G/A 0001140361-22-005071 0001034196 XXXXXXXX LIVE 2 Class A Common Stock, $0.001 par value 03/31/2025 0001861795 Definitive Healthcare Corp. 24477E103 492 Old Connecticut Path, Suite 401 Framingham MA 01701 Rule 13d-1(d) ADVENT INTERNATIONAL, L.P. b DE 58869889 0 58869889 0 58869889 N 54.84 PN The reported percentage is calculated based on 107,341,903 shares of Class A common stock ("Common Stock") outstanding as of May 5, 2025, as reported on the Issuer's 10-Q filed with the Securities and Exchange Commission ("SEC") on May 8, 2025. Advent International GP, LLC b DE 58869889 0 58869889 0 58869889 N 54.84 OO The reported percentage is calculated based on 107,341,903 shares of Common Stock outstanding as of May 5, 2025, as reported on the Issuer's 10-Q filed with the SEC on May 8, 2025. Advent International GPE IX, LLC b DE 46251909 0 46251909 0 46251909 N 43.09 OO The reported percentage is calculated based on 107,341,903 shares of Common Stock outstanding as of May 5, 2025, as reported on the Issuer's 10-Q filed with the SEC on May 8, 2025. GPE IX GP Limited Partnership b E9 36492659 0 36492659 0 36492659 N 34 PN The reported percentage is calculated based on 107,341,903 shares of Common Stock outstanding as of May 5, 2025, as reported on the Issuer's 10-Q filed with the SEC on May 8, 2025. Advent International GPE IX Limited Partnership b E9 16955510 0 16955510 0 16955510 N 15.8 PN The reported percentage is calculated based on 107,341,903 shares of Common Stock outstanding as of May 5, 2025, as reported on the Issuer's 10-Q filed with the SEC on May 8, 2025. Advent International GPE IX-B Limited Partnership b E9 3359809 0 3359809 0 3359809 N 3.13 PN The reported percentage is calculated based on 107,341,903 shares of Common Stock outstanding as of May 5, 2025, as reported on the Issuer's 10-Q filed with the SEC on May 8, 2025. Advent International GPE IX-C Limited Partnership b E9 1394766 0 1394766 0 1394766 N 1.3 PN The reported percentage is calculated based on 107,341,903 shares of Common Stock outstanding as of May 5, 2025, as reported on the Issuer's 10-Q filed with the SEC on May 8, 2025. Advent International GPE IX-F Limited Partnership b E9 1463380 0 1463380 0 1463380 N 1.36 PN The reported percentage is calculated based on 107,341,903 shares of Common Stock outstanding as of May 5, 2025, as reported on the Issuer's 10-Q filed with the SEC on May 8, 2025. Advent International GPE IX-G Limited Partnership b E9 4815226 0 4815226 0 4815226 N 4.49 PN The reported percentage is calculated based on 107,341,903 shares of Common Stock outstanding as of May 5, 2025, as reported on the Issuer's 10-Q filed with the SEC on May 8, 2025. Advent International GPE IX-H Limited Partnership b E9 5428915 0 5428915 0 5428915 N 5.06 PN The reported percentage is calculated based on 107,341,903 shares of Common Stock outstanding as of May 5, 2025, as reported on the Issuer's 10-Q filed with the SEC on May 8, 2025. Advent International GPE IX-I Limited Partnership b E9 3075053 0 3075053 0 3075053 N 2.86 PN The reported percentage is calculated based on 107,341,903 shares of Common Stock outstanding as of May 5, 2025, as reported on the Issuer's 10-Q filed with the SEC on May 8, 2025. GPE IX GP S.a r.l b N4 8301241 0 8301241 0 8301241 N 7.73 CO The reported percentage is calculated based on 107,341,903 shares of Common Stock outstanding as of May 5, 2025, as reported on the Issuer's 10-Q filed with the SEC on May 8, 2025. Advent International GPE IX-A SCSp b N4 4985850 0 4985850 0 4985850 N 4.64 PN The reported percentage is calculated based on 107,341,903 shares of Common Stock outstanding as of May 5, 2025, as reported on the Issuer's 10-Q filed with the SEC on May 8, 2025. Advent International GPE IX-D SCSp b N4 1061241 0 1061241 0 1061241 N 0.99 PN The reported percentage is calculated based on 107,341,903 shares of Common Stock outstanding as of May 5, 2025, as reported on the Issuer's 10-Q filed with the SEC on May 8, 2025. Advent International GPE IX-E SCSp b N4 2156723 0 2156723 0 2156723 N 2.01 PN The reported percentage is calculated based on 107,341,903 shares of Common Stock outstanding as of May 5, 2025, as reported on the Issuer's 10-Q filed with the SEC on May 8, 2025. Advent International GPE IX Strategic Investors SCSp b N4 97427 0 97427 0 97427 N 0.09 PN The reported percentage is calculated based on 107,341,903 shares of Common Stock outstanding as of May 5, 2025, as reported on the Issuer's 10-Q filed with the SEC on May 8, 2025. AP GPE IX GP Limited Partnership b DE 1458009 0 1458009 0 1458009 N 1.36 PN The reported percentage is calculated based on 107,341,903 shares of Common Stock outstanding as of May 5, 2025, as reported on the Issuer's 10-Q filed with the SEC on May 8, 2025. Advent Partners GPE IX Limited Partnership b DE 55642 0 55642 0 55642 N 0.05 PN The reported percentage is calculated based on 107,341,903 shares of Common Stock outstanding as of May 5, 2025, as reported on the Issuer's 10-Q filed with the SEC on May 8, 2025. Advent Partners GPE IX-A Limited Partnership b DE 128669 0 128669 0 128669 N 0.12 PN The reported percentage is calculated based on 107,341,903 shares of Common Stock outstanding as of May 5, 2025, as reported on the Issuer's 10-Q filed with the SEC on May 8, 2025. Advent Partners GPE IX-C Limited Partnership b E9 321070 0 321070 0 321070 N 0.3 PN The reported percentage is calculated based on 107,341,903 shares of Common Stock outstanding as of May 5, 2025, as reported on the Issuer's 10-Q filed with the SEC on May 8, 2025. Advent Partners GPE IX-A Cayman Limited Partnership b E9 54121 0 54121 0 54121 N 0.05 PN The reported percentage is calculated based on 107,341,903 shares of Common Stock outstanding as of May 5, 2025, as reported on the Issuer's 10-Q filed with the SEC on May 8, 2025. Advent Partners GPE IX-B Cayman Limited Partnership b E9 898507 0 898507 0 898507 N 0.84 PN The reported percentage is calculated based on 107,341,903 shares of Common Stock outstanding as of May 5, 2025, as reported on the Issuer's 10-Q filed with the SEC on May 8, 2025. Advent Global Technology LLC b DE 12617980 0 12617980 0 12617980 N 11.75 OO The reported percentage is calculated based on 107,341,903 shares of Common Stock outstanding as of May 5, 2025, as reported on the Issuer's 10-Q filed with the SEC on May 8, 2025. Advent Global Technology GP Limited Partnership b E9 10326106 0 10326106 0 10326106 N 9.62 PN The reported percentage is calculated based on 107,341,903 shares of Common Stock outstanding as of May 5, 2025, as reported on the Issuer's 10-Q filed with the SEC on May 8, 2025. Advent Global Technology Limited Partnership b E9 3818770 0 3818770 0 3818770 N 3.56 PN The reported percentage is calculated based on 107,341,903 shares of Common Stock outstanding as of May 5, 2025, as reported on the Issuer's 10-Q filed with the SEC on May 8, 2025. Advent Global Technology-B Limited Partnership b E9 2971879 0 2971879 0 2971879 N 2.77 PN The reported percentage is calculated based on 107,341,903 shares of Common Stock outstanding as of May 5, 2025, as reported on the Issuer's 10-Q filed with the SEC on May 8, 2025. Advent Global Technology-C Limited Partnership b E9 1609070 0 1609070 0 1609070 N 1.5 PN The reported percentage is calculated based on 107,341,903 shares of Common Stock outstanding as of May 5, 2025, as reported on the Issuer's 10-Q filed with the SEC on May 8, 2025. Advent Global Technology-D Limited Partnership b E9 1926387 0 1926387 0 1926387 N 1.79 PN The reported percentage is calculated based on 107,341,903 shares of Common Stock outstanding as of May 5, 2025, as reported on the Issuer's 10-Q filed with the SEC on May 8, 2025. Advent Global Technology GP S.a r.l. b N4 1885069 0 1885069 0 1885069 N 1.76 CO The reported percentage is calculated based on 107,341,903 shares of Common Stock outstanding as of May 5, 2025, as reported on the Issuer's 10-Q filed with the SEC on May 8, 2025. Advent Global Technology-A SCSP b N4 1885069 0 1885069 0 1885069 N 1.76 PN The reported percentage is calculated based on 107,341,903 shares of Common Stock outstanding as of May 5, 2025, as reported on the Issuer's 10-Q filed with the SEC on May 8, 2025. AP AGT GP Limited Partnership b DE 406805 0 406805 0 406805 N 0.38 PN The reported percentage is calculated based on 107,341,903 shares of Common Stock outstanding as of May 5, 2025, as reported on the Issuer's 10-Q filed with the SEC on May 8, 2025. Advent Partners AGT Limited Partnership b DE 31561 0 31561 0 31561 N 0.03 PN The reported percentage is calculated based on 107,341,903 shares of Common Stock outstanding as of May 5, 2025, as reported on the Issuer's 10-Q filed with the SEC on May 8, 2025. Advent Partners AGT-A Limited Partnership b DE 27373 0 27373 0 27373 N 0.03 PN The reported percentage is calculated based on 107,341,903 shares of Common Stock outstanding as of May 5, 2025, as reported on the Issuer's 10-Q filed with the SEC on May 8, 2025. Advent Partners AGT-C Limited Partnership b E9 317329 0 317329 0 317329 N 0.3 PN The reported percentage is calculated based on 107,341,903 shares of Common Stock outstanding as of May 5, 2025, as reported on the Issuer's 10-Q filed with the SEC on May 8, 2025. Advent Global Technology Strategic Investors Limited Partnership b E9 30542 0 30542 0 30542 N 0.03 PN The reported percentage is calculated based on 107,341,903 shares of Common Stock outstanding as of May 5, 2025, as reported on the Issuer's 10-Q filed with the SEC on May 8, 2025. Advent Global Opportunities Management LLC b DE 3623787 0 3623787 0 3623787 N 3.38 OO The reported percentage is calculated based on 107,341,903 shares of Common Stock outstanding as of May 5, 2025, as reported on the Issuer's 10-Q filed with the SEC on May 8, 2025. Advent Global Opportunities GP LLC b DE 3623787 0 3623787 0 3623787 N 3.38 OO The reported percentage is calculated based on 107,341,903 shares of Common Stock outstanding as of May 5, 2025, as reported on the Issuer's 10-Q filed with the SEC on May 8, 2025. Advent Global Opportunities GP LP b E9 3623787 0 3623787 0 3623787 N 3.38 PN The reported percentage is calculated based on 107,341,903 shares of Common Stock outstanding as of May 5, 2025, as reported on the Issuer's 10-Q filed with the SEC on May 8, 2025. Advent Global Opportunities Master Limited Partnership b E9 3623787 0 3623787 0 3623787 N 3.38 PN The reported percentage is calculated based on 107,341,903 shares of Common Stock outstanding as of May 5, 2025, as reported on the Issuer's 10-Q filed with the SEC on May 8, 2025. Definitive Healthcare Corp. 492 Old Connecticut Path, Suite 401, Framingham, Massachusetts, 01701 This statement is being jointly filed by each of the persons below pursuant to Rule 13d-1(k) promulgated by the SEC pursuant to Section 13 of the Act, all of whom together are referred to herein as the "Reporting Persons": (i) Advent International, L.P., a Delaware limited partnership (f/k/a Advent International Corporation); (ii) Advent International GP, LLC, a Delaware limited liability company; (iii) Advent International GPE IX, LLC, a Delaware limited liability company; (iv) GPE IX GP Limited Partnership, a Cayman Islands limited partnership; (v) Advent International GPE IX Limited Partnership, a Cayman Islands limited partnership; (vi) Advent International GPE IX-B Limited Partnership, a Cayman Islands limited partnership; (vii) Advent International GPE IX-C Limited Partnership, a Cayman Islands limited partnership; (viii) Advent International GPE IX-F Limited Partnership, a Cayman Islands limited partnership; (ix) Advent International GPE IX-G Limited Partnership, a Cayman Islands limited partnership; (x) Advent International GPE IX-H Limited Partnership, a Cayman Islands limited partnership; (xi) Advent International GPE IX-I Limited Partnership, a Cayman Islands limited partnership (the funds set forth in the foregoing clauses (v)-(xi), the "Advent IX Cayman Funds"); (xii) GPE IX GP S.a.r.l., a Luxembourg Societe a responsabilite limitee; (xiii) Advent International GPE IX-A SCSp, a Luxembourg societe en commandite speciale; (xiv) Advent International GPE IX-D SCSp, a Luxembourg societe en commandite speciale; (xv) Advent International GPE IX-E SCSp, a Luxembourg societe en commandite speciale; (xvi) Advent International GPE IX Strategic Investors SCSp, a Luxembourg societe en commandite speciale; (the funds set forth in the foregoing clauses (xiii)-(xvi), the "Advent IX Luxembourg Funds"); (xvii) AP GPE IX GP Limited Partnership, a Delaware limited partnership; (xviii) Advent Partners GPE IX Limited Partnership, a Delaware limited partnership; (xix) Advent Partners GPE IX-A Limited Partnership, a Delaware limited partnership; (xx) Advent Partners GPE IX-C Limited Partnership, a Cayman Islands limited partnership (f/k/a Advent Partners GPE IX Cayman LP); (xxi) Advent Partners GPE IX-A Cayman Limited Partnership, a Cayman Islands limited partnership; (xxii) Advent Partners GPE IX-B Cayman Limited Partnership, a Cayman Islands limited partnership (the funds set forth in the foregoing clauses (xviii)-(xxii), the "Advent IX Partners Funds"); (xxiii) Advent Global Technology LLC, a Delaware limited liability company; (xxiv) Advent Global Technology GP Limited Partnership, a Cayman Islands limited partnership; (xxv) Advent Global Technology Limited Partnership, a Cayman Islands limited partnership; (xxvi) Advent Global Technology-B Limited Partnership, a Cayman Islands limited partnership; (xxvii) Advent Global Technology-C Limited Partnership, a Cayman Islands limited partnership; (xxviii) Advent Global Technology-D Limited Partnership, a Cayman Islands limited partnership (the funds set forth in the foregoing clauses (xxv)-(xxviii), the "Advent Global Technology Funds"); (xxix) Advent Global Technology GP S.a r.l., a Luxembourg Societe a responsabilite limitee; (xxx) Advent Global Technology-A SCSP, a Luxembourg societe en commandite speciale; (xxxi) AP AGT GP Limited Partnership, a Delaware limited partnership; (xxxii) Advent Partners AGT Limited Partnership, a Delaware limited partnership; (xxxiii) Advent Partners AGT-A Limited Partnership, a Delaware limited partnership; (xxxiv) Advent Partners AGT-C Limited Partnership, a Cayman Islands limited partnership (f/k/a Advent Partners AGT-Cayman Limited Partnership); (xxxv) Advent Global Technology Strategic Investors Limited Partnership, a Cayman Islands limited partnership (the funds set forth in the foregoing clauses (xxxii)-(xxxv), the "Advent AGT Funds"); (xxxvi) Advent Global Opportunities Management LLC, a Delaware limited liability company; (xxxvii) Advent Global Opportunities GP LLC, a Delaware limited liability company; (xxxviii) Advent Global Opportunities GP LP, a Cayman Islands limited partnership; (xxxix) Advent Global Opportunities Master Limited Partnership, a Cayman Islands limited partnership ("Advent Global Opportunities Master Fund"). GPE IX GP Limited Partnership is the general partner of the Advent IX Cayman Funds, GPE IX GP S.a r.l. is the general partner of the Advent IX Luxembourg Funds, and AP GPE IX GP Limited Partnership is the general partner of the Advent IX Partners Funds. Advent International GPE IX, LLC is the general partner of GPE IX GP Limited Partnership and AP GPE IX GP Limited Partnership, and is the manager of GPE IX GP S.a r.l. Advent Global Technology GP Limited Partnership is the general partner of the Advent Global Technology Funds, Advent Global Technology GP S.a r.l. is the general partner of Advent Global Technology-A SCSp, and AP AGT GP Limited Partnership is the general partner of the Advent AGT Funds. Advent Global Technology LLC is the general partner of Advent Global Technology GP Limited Partnership and AP AGT GP Limited Partnership, and is the manager of Advent Global Technology GP S.a r.l. Advent Global Opportunities GP LP is the general partner of Advent Global Opportunities Master Fund, Advent Global Opportunities GP LLC is the general partner of Advent Global Opportunities GP LP, and Advent Global Opportunities Management LLC is the investment manager to Advent Global Opportunities Master Fund. Investors in Advent Global Opportunities Master Fund invest in one or more of the following feeder funds: Advent Global Opportunities Fund LP, Advent Global Opportunities Limited Partnership, Advent Global Opportunities Fund Ltd. and Advent Global Opportunities Ltd. (collectively, the "Advent Global Opportunities Feeder Funds"), which are the limited partners of Advent Global Opportunities Master Fund. The Advent Global Opportunities Feeder Funds have ownership interests in Advent Global Opportunities Master Fund, but none of the Advent Global Opportunities Feeder Funds owns shares directly and none has voting or dispositive power over the shares held directly by Advent Global Opportunities Master Fund. The various Advent Global Opportunities entities referenced in this Item 2 were previously branded as Sunley House. Advent International GP, LLC is the general partner of Advent International, L.P., and Advent International, L.P. is the manager of Advent International GPE IX, LLC and Advent Global Technology LLC and is the sole member of both Advent Global Opportunities GP LLC and Advent Global Opportunities Management LLC. Each of Advent International GP, LLC and Advent International, L.P. may be deemed to have voting and dispositive power over the shares held by the Advent IX Cayman Funds, the Advent IX Luxembourg Funds, the Advent IX Partners Funds, the Advent Global Technology funds, Advent Global Technology-A SCSp, the Advent AGT Funds and Advent Global Opportunities Master Fund. Prudential Tower, 800 Boylston Street, Boston, Massachusetts 02199 See responses to row 4 on each cover page. Y See responses to row 9 on each cover page hereto which, together with the information set forth in Item 2 of this Statement, are incorporated by reference into this Item 4. See responses to row 11 on each cover page. See responses to row 5 on each cover page. See responses to row 6 on each cover page. See responses to row 7 on each cover page. See responses to row 8 on each cover page. Y Y Y Y Y Y 99.1 Joint Filing Agreement, dated May 15, 2025 99.2 Signature Page, dated May 15, 2025 ADVENT INTERNATIONAL, L.P. /s/ Neil Crawford 05/15/2025 Advent International GP, LLC /s/ Neil Crawford 05/15/2025 Advent International GPE IX, LLC /s/ Neil Crawford 05/15/2025 GPE IX GP Limited Partnership /s/ Neil Crawford 05/15/2025 Advent International GPE IX Limited Partnership /s/ Neil Crawford 05/15/2025 Advent International GPE IX-B Limited Partnership /s/ Neil Crawford 05/15/2025 Advent International GPE IX-C Limited Partnership /s/ Neil Crawford 05/15/2025 Advent International GPE IX-F Limited Partnership /s/ Neil Crawford 05/15/2025 Advent International GPE IX-G Limited Partnership /s/ Neil Crawford 05/15/2025 Advent International GPE IX-H Limited Partnership /s/ Neil Crawford 05/15/2025 Advent International GPE IX-I Limited Partnership /s/ Neil Crawford 05/15/2025 GPE IX GP S.a r.l /s/ Justin Nuccio 05/15/2025 Advent International GPE IX-A SCSp /s/ Justin Nuccio 05/15/2025 Advent International GPE IX-D SCSp /s/ Justin Nuccio 05/15/2025 Advent International GPE IX-E SCSp /s/ Justin Nuccio 05/15/2025 Advent International GPE IX Strategic Investors SCSp /s/ Justin Nuccio 05/15/2025 AP GPE IX GP Limited Partnership /s/ Neil Crawford 05/15/2025 Advent Partners GPE IX Limited Partnership /s/ Neil Crawford 05/15/2025 Advent Partners GPE IX-A Limited Partnership /s/ Neil Crawford 05/15/2025 Advent Partners GPE IX-C Limited Partnership /s/ Neil Crawford 05/15/2025 Advent Partners GPE IX-A Cayman Limited Partnership /s/ Neil Crawford 05/15/2025 Advent Partners GPE IX-B Cayman Limited Partnership /s/ Neil Crawford 05/15/2025 Advent Global Technology LLC /s/ Neil Crawford 05/15/2025 Advent Global Technology GP Limited Partnership /s/ Neil Crawford 05/15/2025 Advent Global Technology Limited Partnership /s/ Neil Crawford 05/15/2025 Advent Global Technology-B Limited Partnership /s/ Neil Crawford 05/15/2025 Advent Global Technology-C Limited Partnership /s/ Neil Crawford 05/15/2025 Advent Global Technology-D Limited Partnership /s/ Neil Crawford 05/15/2025 Advent Global Technology GP S.a r.l. /s/ Justin Nuccio 05/15/2025 Advent Global Technology-A SCSP /s/ Justin Nuccio 05/15/2025 AP AGT GP Limited Partnership /s/ Neil Crawford 05/15/2025 Advent Partners AGT Limited Partnership /s/ Neil Crawford 05/15/2025 Advent Partners AGT-A Limited Partnership /s/ Neil Crawford 05/15/2025 Advent Partners AGT-C Limited Partnership /s/ Neil Crawford 05/15/2025 Advent Global Technology Strategic Investors Limited Partnership /s/ Neil Crawford 05/15/2025 Advent Global Opportunities Management LLC /s/ Neil Crawford 05/15/2025 Advent Global Opportunities GP LLC /s/ Neil Crawford 05/15/2025 Advent Global Opportunities GP LP /s/ Neil Crawford 05/15/2025 Advent Global Opportunities Master Limited Partnership /s/ Neil Crawford 05/15/2025