SEC Form 3

FORM 3

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940

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1. Name and Address of Reporting Person* SEA VII Management, LLC (Last) (First) (Middle) 140 NEW MONTGOMERY STREET, 20TH FLOOR (Street) SAN FRANCISCO CA 94105 (City) (State) (Zip)	2. Date of Event Requiring Statement (Month/Day/Year) 09/15/2021	3. Issuer Name and Ticker or Trading Symbol Definitive Healthcare Corp. [ DH ]
		4. Relationship of Reporting Person(s) to Issuer (Check all applicable) X Director X 10% Owner Officer (give title below) Other (specify below)	5. If Amendment, Date of Original Filed (Month/Day/Year)
			6. Individual or Joint/Group Filing (Check Applicable Line) Form filed by One Reporting Person X Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Beneficially Owned
1. Title of Security (Instr. 4)	2. Amount of Securities Beneficially Owned (Instr. 4)	3. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	4. Nature of Indirect Beneficial Ownership (Instr. 5)
Class A Common Stock	2,952,733(1)	I	See notes(2)(3)(4)
Class B Common Stock	28,352,972(1)	I	See notes(2)(3)(4)

Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 4)	2. Date Exercisable and Expiration Date (Month/Day/Year)		3. Title and Amount of Securities Underlying Derivative Security (Instr. 4)		4. Conversion or Exercise Price of Derivative Security	5. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	6. Nature of Indirect Beneficial Ownership (Instr. 5)
	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
LLC Units of AIDH Topco, LLC	(5)	(5)	Class A common stock	28,352,972	(5)	I	See notes(2)(3)(4)

1. Name and Address of Reporting Person* SEA VII Management, LLC (Last) (First) (Middle) 140 NEW MONTGOMERY STREET, 20TH FLOOR (Street) SAN FRANCISCO CA 94105 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer X Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* SE VII DHC AIV, L.P. (Last) (First) (Middle) 140 NEW MONTGOMERY STREET, 20TH FLOOR (Street) SAN FRANCISCO 94105 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer X Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* Spectrum VII Investment Managers' Fund, L.P. (Last) (First) (Middle) 140 NEW MONTGOMERY STREET, 20TH FLOOR (Street) SAN FRANCISCO 94105 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer X Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* SE VII DHC AIV Feeder, L.P. (Last) (First) (Middle) 140 NEW MONTGOMERY STREET, 20TH FLOOR (Street) SAN FRANCISCO CA 94105 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer X Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* Spectrum VII Co-Investment Fund, L.P. (Last) (First) (Middle) 140 NEW MONTGOMERY STREET, 20TH FLOOR (Street) SAN FRANCISCO CA 94105 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer X Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* Spectrum Equity Associates VII, L.P. (Last) (First) (Middle) 140 NEW MONTGOMERY STREET, 20TH FLOOR (Street) SAN FRANCISCO CA 94105 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer X Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* Mitchell Christopher (Last) (First) (Middle) 140 NEW MONTGOMERY STREET, 20TH FLOOR (Street) SAN FRANCISCO CA 94105 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer X Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* Haywood Jeffrey Charles (Last) (First) (Middle) 140 NEW MONTGOMERY STREET, 20TH FLOOR (Street) SAN FRANCISCO CA (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer X Director X 10% Owner Officer (give title below) Other (specify below)

Explanation of Responses:

1. See Exhibit 99.1 for text of footnote (1).

2. See Exhibit 99.1 for text of footnote (2).

3. See Exhibit 99.1 for text of footnote (3).

4. See Exhibit 99.1 for text of footnote (4).

5. See Exhibit 99.1 for text of footnote (5).

Remarks:

Christopher T. Mitchell, a Managing Director of Spectrum and Jeffrey C. Haywood, a Managing Director of Spectrum (together, the "Spectrum Directors"), each serve on the board of directors of the Issuer, and have been deputized to represent the Reporting Persons on the board of directors. By virtue of the Spectrum Directors' representation, for purposes of Section 16 of the Securities Exchange Act of 1934, each of the Reporting Persons may be deemed directors by deputization of the Issuer. The Spectrum Directors have filed separate Section 16 reports disclosing securities of the Issuer that they may be deemed to beneficially own for Section 16 purposes. Exhibit 99.1 (Footnotes to Form 3) and Exhibit 99.2 (Signatures and Joint Filer Information) are incorporated by reference.

	SEA VII MANAGEMENT, LLC, By: /s/ Carolina A. Picazo, Chief Administrative Officer & Chief Compliance Officer	09/15/2021
	SE VII DHC AIV, L.P. By: Spectrum Equity Associates VII, L.P., its general partner, By: SEA VII Management, LLC, its general partner, By: /s/Carolina A. Picazo, its Chief Administrative Officer & Chief Compliance Officer	09/15/2021
	SE VII DHC AIV FEEDER, L.P., By: Spectrum Equity Associates VII, L.P., its general partner, By: SEA Management, LLC, its general partner, By: /s/ Carolina A. Picazo, Chief Administrative Officer & Chief Compliance Officer	09/15/2021
	SPECTRUM VII INVESTMENT MANAGERS' FUND, L.P., By: SEA Management, LLC, its general partner, By: /s/ Carolina A. Picazo, Chief Administrative Officer & Chief Compliance Officer	09/15/2021
	SPECTRUM VII CO-INVESTMENT FUND, L.P., By: /s/ Carolina A. Picazo, Chief Administrative Officer & Chief Compliance Officer	09/15/2021
	SPECTRUM EQUITY ASSOCIATES VII, L.P., By: SEA Management, LLC, its general partner, By: /s/ Carolina A. Picazo, Chief Administrative Officer & Chief Compliance Officer	09/15/2021
	CHRISTOPHER T. MITCHELL, By: /s/ Christopher T. Mitchell	09/15/2021
	JEFFREY C. HAYWOOD, By: /s/ Jeffrey C. Haywood	09/15/2021
	** Signature of Reporting Person	Date
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