Definitive Healthcare (DH) 10-Q8 Nov 212021 Q3 Quarterly reportFinancial data

Company Profile

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
Document and Entity Information - shares	Sep. 30, 2021	Nov. 05, 2021
Document Information [Line Items]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2021
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q3
Entity Registrant Name	Definitive Healthcare Corp.
Entity Central Index Key	0001861795
Entity Tax Identification Number	86-3988281
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Filer Category	Non-accelerated Filer
Entity File Number	001-40815
Entity Shell Company	false
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Entity Small Business	false
Entity Interactive Data Current	Yes
Entity Incorporation, State or Country Code	DE
Entity Address, Address Line One	550 Cochituate Road
Entity Address, City or Town	Framingham
Entity Address, State or Province	MA
Entity Address, Postal Zip Code	01701
City Area Code	508
Local Phone Number	720-4224
Trading Symbol	DH
Title of 12(b) Security	Class A Common Stock, $0.001 par value
Security Exchange Name	NASDAQ
Document Quarterly Report	true
Document Transition Report	false
Entity Common Stock Shares Outstanding		88,263,333

CONDENSED CONSOLIDATED BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 189,752	$ 24,774
Accounts receivable, net	27,886	33,108
Prepaid expenses and other current assets	3,642	3,016
Current portion of deferred contract costs	5,359	2,947
Total current assets	226,639	63,845
Property and equipment, net	4,697	3,248
Other assets	747	472
Deferred contract costs, net of current portion	9,388	5,952
Deferred tax asset	161	161
Intangible assets, net	366,723	410,237
Goodwill	1,261,444	1,261,444
Total assets	1,869,799	1,745,359
Current liabilities:
Accounts payable	7,055	5,662
Accrued expenses and other current liabilities	19,296	17,321
Current portion of deferred revenue	69,811	61,060
Current portion of term loan	6,875	4,680
Total current liabilities	103,037	88,723
Long term liabilities:
Deferred revenue	368	140
Tax receivable agreements liability	146,106
Term loan, net of current portion	265,388	457,197
Deferred tax liabilities	71,341
Other long-term liabilities	475	3,736
Total liabilities	586,715	549,796
Commitments and Contingencies (Note 11)
Equity:
Members' equity	0	1,195,694
Additional paid-in capital	700,773
Accumulated other comprehensive income (loss)	24	(131)
Accumulated deficit	(7,978)
Noncontrolling interests	590,177
Total equity	1,283,084	1,195,563
Total liabilities and equity	1,869,799	$ 1,745,359
Class A Common Stock
Equity:
Common stock, value	88
Class B Common Stock
Equity:
Common stock, value	$ 0

CONDENSED CONSOLIDATED BALANC_2

CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical)	Sep. 30, 2021$ / sharesshares
Class A Common Stock
Common stock, par value \| $ / shares	$ 0.001
Common stock, shares authorized	600,000,000
Common stock, shares issued	88,263,333
Common stock, shares outstanding	88,263,333
Class B Common Stock
Common stock, par value \| $ / shares	$ 0
Common stock, shares authorized	65,000,000
Common stock, shares issued	60,020,525
Common stock, shares outstanding	57,220,661

CONDENSED CONSOLIDATED STATEMEN

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (Unaudited) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Income Statement [Abstract]
Revenue		$ 43,084	$ 30,073	$ 119,841	$ 84,659
Cost of revenue:
Cost of revenue exclusive of amortization shown below		5,129	2,619	13,895	7,876
Amortization		5,356	4,794	15,896	14,278
Gross profit		32,599	22,660	90,050	62,505
Operating expenses:
Sales and marketing		14,376	8,292	39,003	23,542
Product development		4,746	2,618	12,817	7,566
General and administrative		7,880	2,538	18,891	8,105
Depreciation and amortization		9,760	10,112	28,814	30,037
Transaction expenses		(137)	40	3,332	748
Total operating expenses		36,625	23,600	102,857	69,998
Loss from operations		(4,026)	(940)	(12,807)	(7,493)
Other expense, net:
Foreign currency transaction gain		119		143
Interest expense, net		(7,186)	(9,022)	(23,956)	(27,802)
Loss on extinguishment of debt		(9,873)		(9,873)
Total other expense, net		(16,940)	(9,022)	(33,686)	(27,802)
Net loss		(20,966)	(9,962)	(46,493)	(35,295)
Less: Net loss attributable to Definitive OpCo prior to the Reorganization Transactions		(7,816)	$ (9,962)	(33,343)	$ (35,295)
Less: Net loss attributable to noncontrolling interests		(5,172)		(5,172)
Net loss attributable to Definitive Healthcare Corp.		$ (7,978)		$ (7,978)
Net loss per share of Class A common stock:
Basic and diluted		$ (0.09)		$ (0.09)
Weighted average Common Stock outstanding:
Basic and diluted	[1]	88,263,333		88,263,333

[1]	Basic and diluted net loss per share of Class A Common Stock is applicable only for the period from September 15, 2021 through September 30, 2021, which is the period following the initial public offering ("IPO") and related Reorganization Transactions (as defined in Note 1 to the Unaudited Consolidated Financial Statements). See Note 16 for the number of shares used in the computation of net loss per share of Class A Common Stock and the basis for the computation of net loss per share.

CONDENSED CONSOLIDATED STATEM_2

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Statement Of Income And Comprehensive Income [Abstract]
Net loss	$ (20,966)	$ (9,962)	$ (46,493)	$ (35,295)
Other comprehensive loss:
Foreign currency translation adjustments	11	0	155	0
Comprehensive loss	(20,955)	(9,962)	(46,338)	(35,295)
Less: Net loss attributable to Definitive OpCo prior to the Reorganization Transactions	(7,818)		(33,201)
Less: Comprehensive loss attributable to noncontrolling interests	(5,167)		(5,167)
Comprehensive loss attributable to Definitive Healthcare Corp.	$ (7,970)	$ (9,962)	$ (7,970)	$ (35,295)

CONDENSED CONSOLIDATED STATEM_3

CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN MEMBERS EQUITY AND TOTAL EQUITY(Unaudited) - USD ($) $ in Thousands	Total	IPO	Reorganization Transactions	Definitive Healthcare Corp. [Member]IPO	Definitive OpCo [Member]IPO	Class A Units	Class A UnitsIPO	Class A UnitsDefinitive Healthcare Corp. [Member]IPO	Class B Units	Class B UnitsDefinitive OpCo [Member]IPO	Members Equity	Additional Paid In Capital	Additional Paid In CapitalIPO	Additional Paid In CapitalDefinitive Healthcare Corp. [Member]IPO	Additional Paid In CapitalDefinitive OpCo [Member]IPO	Accumulated Deficit	Accumulated DeficitReorganization Transactions	Accumulated Other Comprehensive (Loss) Income	Accumulated Other Comprehensive (Loss) IncomeIPO	Noncontrolling Interest	Noncontrolling InterestReorganization Transactions	Previously Reported [Member]	Previously Reported [Member]Members Equity	Previously Reported [Member]Accumulated Other Comprehensive (Loss) Income
Beginning Balance at Dec. 31, 2019											$ 1,216,240
Net loss											(13,835)
Equity-based compensation											430
Ending Balance at Mar. 31, 2020											1,202,835
Beginning Balance at Dec. 31, 2019											1,216,240
Net loss prior to Reorganization Transactions
Ending Balance at Sep. 30, 2020											1,180,168
Beginning Balance at Dec. 31, 2019											1,216,240
Ending Balance at Dec. 31, 2020																						$ 1,195,563	$ 1,195,694	$ (131)
Beginning Balance at Mar. 31, 2020											1,202,835
Net loss											(11,498)
Equity-based compensation											442
Distributions to members											(48)
Ending Balance at Jun. 30, 2020											1,191,731
Net loss											(9,962)
Net loss prior to Reorganization Transactions
Equity-based compensation											458
Distributions to members											(2,059)
Ending Balance at Sep. 30, 2020											1,180,168
Beginning Balance at Dec. 31, 2020																						1,195,563	1,195,694	(131)
Net loss prior to Reorganization Transactions																						(10,487)	(10,487)
Other comprehensive income (loss)																						163		163
Equity-based compensation																						406	406
Ending Balance at Mar. 31, 2021																						1,185,645	1,185,613	32
Beginning Balance at Dec. 31, 2020																						1,195,563	1,195,694	(131)
Net loss	(7,978)
Net loss prior to Reorganization Transactions	(33,201)
Equity-based compensation	300
Members' contributions	5,500
Ending Balance at Sep. 30, 2021	1,283,084					$ 88						$ 700,773				$ (7,978)		$ 24		$ 590,177
Ending Balance (in shares) at Sep. 30, 2021						88,263,333			60,020,525
Beginning Balance at Mar. 31, 2021																						1,185,645	1,185,613	32
Net loss prior to Reorganization Transactions																						(15,040)	(15,040)
Other comprehensive income (loss)																						(19)		(19)
Equity-based compensation																						1,615	1,615
Members' contributions																						5,500	5,500
Distributions to members																						(3,328)	(3,328)
Ending Balance at Jun. 30, 2021																						1,174,373	1,174,360	13
Net loss	(7,978)		$ (13,150)														$ (7,978)				$ (5,172)
Net loss prior to Reorganization Transactions	(7,818)																					(7,816)	(7,816)
Other comprehensive income (loss)		$ 13																	$ 13			(2)		$ (2)
Equity-based compensation	2,595											1,574								1,021		278	(278)
Distributions to members																						$ (3,811)	$ (3,811)
Initial effect of the Reorganization Transactions and IPO on noncontrolling interests	(217,446)					$ 73					$ (1,162,455)	351,075								593,861
Initial effect of the Reorganization Transactions and IPO on noncontrolling interests, Share						72,871,733			61,262,052
Issuance of Class A common stock in IPO, net of costs		$ 441,418					$ 18						$ 441,400
Issuance of Class A common stock in IPO net of costs, Share							17,888,888
Repurchase of share				$ (63,212)	$ (29,600)			$ (3)						$ (63,209)	$ (29,600)
Repurchase of share, Shares								(2,497,288)		(1,169,378)
Forfeited unvested incentive units									(72,149)
Vested incentive units, value												(467)								467
Ending Balance at Sep. 30, 2021	$ 1,283,084					$ 88						$ 700,773				$ (7,978)		$ 24		$ 590,177
Ending Balance (in shares) at Sep. 30, 2021						88,263,333			60,020,525

CONDENSED CONSOLIDATED STATEM_4

CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN MEMBERS' EQUITY AND TOTAL EQUITY (Parenthetical) $ in Thousands	3 Months Ended
	Sep. 30, 2021USD ($)
Class A Units \| IPO
Stock issuance cost, net	$ 11,394

CONDENSED CONSOLIDATED STATEM_5

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Cash flows provided by operating activities:
Net loss	$ (46,493)	$ (35,295)
Adjustments to reconcile net loss to net cash provided by (used in) operating activities:
Depreciation and amortization	1,193	817
Amortization of intangible assets	43,517	43,498
Amortization of deferred contract costs	3,195	1,038
Equity-based compensation	4,338	1,330
Noncash paid in kind interest expense		7,371
Amortization of debt issuance costs	1,522	1,541
Provision for doubtful accounts receivable	76	579
Loss on extinguishment of debt (non-cash portion)	9,843
Changes in fair value of contingent consideration	3,169
Changes in operating assets and liabilities:
Accounts receivable	5,179	3,936
Prepaid expenses and other current assets	(561)	(39)
Deferred contract costs	(9,043)	(4,341)
Accounts payable, accrued expenses and other current liabilities	(3,965)	(7,283)
Deferred revenue	9,023	1,392
Net cash provided by operating activities	20,993	14,544
Cash flows used in investing activities:
Purchases of property, equipment, and other assets	(5,662)	(1,061)
Cash paid for acquisitions, net of cash acquired		(6,935)
Net cash used in investing activities	(5,662)	(7,996)
Cash flows provided by (used in) financing activities:
Proceeds from term loan	275,000
Repayments of term loans	(472,742)	(3,375)
Proceeds from revolving credit facility		25,000
Payment of contingent consideration	(1,500)
Payment of debt issuance costs	(3,511)
Proceeds from equity offering, net of underwriting discounts	452,812
Repurchase of outstanding equity / Definitive OpCo units	(92,812)
Payments of IPO issuance costs	(5,913)
Member contributions	5,500
Member distributions	(7,139)	(2,109)
Net cash provided by financing activities	149,695	19,516
Net increase in cash and cash equivalents	165,026	26,064
Effect of exchange rate changes on cash and cash equivalents	(48)
Cash and cash equivalents, beginning of period	24,774	8,618
Cash and cash equivalents, end of period	189,752	34,682
Supplemental cash flow disclosures:
Cash paid for interest	27,587	$ 23,043
Cash paid for income taxes	13
Supplemental disclosure of non-cash investing activities:
Net decrease in accrued capital expenditures, including purchases of data	(3,020)
Supplemental disclosure of non-cash financing activities:
Increase in unpaid public offering costs	$ 5,481

Description of Business

Description of Business	9 Months Ended
Description of Business	Sep. 30, 2021
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Description of Business	1. Description of Business Definitive Healthcare Corp. (together with its subsidiaries, “Definitive Healthcare” or the “Company”), through its operating subsidiary, AIDH TopCo, LLC (“Definitive OpCo”), provides comprehensive and up-to-date hospital and healthcare-related information and insight across the entire healthcare continuum via a multi-tenant database platform which combines proprietary and public sources to deliver insights. Unless otherwise stated, references to “we,” “us,” “our,” “Definitive Healthcare” and the “Company” refer (1) prior to the consummation of the Reorganization Transactions (as defined below), to Definitive OpCo and its consolidated subsidiaries, and (2) after the consummation of the Reorganization Transactions, to Definitive Healthcare Corp. and its consolidated subsidiaries. On October 27, 2020, Definitive OpCo completed the purchase of all of the outstanding shares of Monocl Holding Company ("Monocl"), a cloud-based platform with millions of expert profiles. Refer to Note 3. Business Combinations , for additional information. Organization Definitive Healthcare Corp. was formed on May 5, 2021 as a Delaware corporation for the purposes of facilitating an initial public offering (“IPO”) and other related transactions in order to carry on the business of Definitive OpCo, a Delaware limited liability company. Following consummation of the Reorganization Transactions, Definitive OpCo became an indirect subsidiary of Definitive Healthcare Corp. The Company is headquartered in Framingham, MA, with three other offices in the United States and one in Sweden. Initial Public Offering On September 17, 2021, Definitive Healthcare completed its IPO, in which it sold 17,888,888 shares of Class A Common Stock (including shares issued pursuant to the exercise in full of the underwriters’ option to purchase additional shares) at a public offering price of $ 27.00 per share for net proceeds of $ 452.8 million, after deducting underwriters’ discounts and commissions (but excluding other offering expenses and reimbursements). Definitive Healthcare used proceeds from the IPO to (i) acquire 14,222,222 newly issued limited liability company interests (“LLC Units”) from Definitive OpCo; (ii) purchase 1,169,378 LLC Units from certain holders of LLC Units prior to the IPO; and (iii) repurchase 2,497,288 shares of Class A Common Stock received by the former shareholders of certain Blocker Companies (as defined below). Reorganization Transactions In connection with the IPO, the Company completed the following transactions (the “Reorganization Transactions”). Definitive OpCo entered into an amended and restated limited liability company agreement (the “Amended LLC Agreement”) pursuant to which members of Definitive OpCo prior to the IPO who continue to hold LLC Units, have the right to require Definitive OpCo to exchange all or a portion of their LLC Units for newly issued shares of Class A Common Stock. Entities treated as corporations for U.S. tax purposes that hold LLC Units (individually, a “Blocker Company” and collectively, the "Blocker Companies") each merged with a merger subsidiary and subsequently merged into Definitive Healthcare Corp. Except for AIDH Management Holdings, LLC, members of AIDH Management Holdings, LLC, received a number of shares of Definitive Healthcare Corp. Class B Common Stock with no par value per share. The total shares of Class B Common Stock outstanding is equal to the number of LLC Units outstanding. AIDH Management Holdings, LLC is a special purpose investment vehicle through which certain persons, primarily our employees and certain legacy investors, indirectly hold interests in Definitive OpCo; the holders of interests in AIDH Management Holdings, LLC received a number of shares of Definitive Healthcare Corp. Class B Common Stock. In connection with the Reorganization Transactions and the IPO, Definitive Healthcare Corp. entered into a tax receivable agreement. See Note 15. Income Taxes .

Summary of Significant Accounti

Summary of Significant Accounting Policies	9 Months Ended
Summary of Significant Accounting Policies	Sep. 30, 2021
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	2. Summary of Significant Accounting Policies Basis of Presentation The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States (“GAAP”) and in conformity with rules applicable to quarterly financial information. The Financial Accounting Standards Board (“FASB”) establishes these principles to ensure financial condition, results of operations, and cash flows are consistently reported. Any reference in these notes to applicable accounting guidance is meant to refer to the authoritative nongovernmental GAAP as found in the FASB Accounting Standards Codification (“ASC”). The condensed consolidated financial statements as of September 30, 2021 and for the three and nine months ended September 30, 2021 and 2020 are unaudited. Amounts for the period from January 1, 2020 through September 15, 2021 presented in the condensed consolidated financial statements and notes to the condensed consolidated financial statements herein represent the historical operations of Definitive OpCo. The amounts as of September 30, 2021 and for the period from September 16, 2021 reflect the consolidated operations of Definitive Healthcare Corp. and its consolidated subsidiaries. All adjustments, consisting of normal recurring adjustments, except as otherwise noted, considered necessary for a fair presentation of the unaudited interim condensed consolidated financial statements for these interim periods have been included. Refer to Note 2. Summary of Significant Accounting Policies of the Notes to the Consolidated Financial Statements in the Company’s final prospectus dated September 14, 2021 filed with the Securities and Exchange Commission ("SEC") pursuant to Rule 424(b) of the Securities Act of 1933, as amended, on September 16, 2021 (the "IPO Prospectus") for the Company’s accounting policies and estimates. Adoption of Recently Issued Financial Accounting Standards In August 2018, the FASB issued ASU No. 2018-15— Intangibles — Goodwill and Other — Internal-Use Software (Subtopic 350-40), Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract . This standard aligns the requirements for capitalizing implementation costs incurred in a hosting arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software. The amendment is effective for fiscal years beginning after December 15, 2020 and early adoption is permitted. The Company adopted the update effective January 1, 2021. The adoption did not have a material impact on the consolidated financial statements. Recently-Issued Accounting Pronouncements Not Yet Adopted In February 2016, the FASB issued ASU 2016-02— Leases . The new standard establishes a right-of-use (“ROU”) model that requires a lessee to record a ROU asset and a lease liability on the balance sheet for all leases with terms longer than twelve months. Leases will be classified as either finance or operating, with classification affecting the pattern of expense recognition in the income statement. The FASB has subsequently issued supplemental and/or clarifying ASUs inclusive of ASU 2020-05, which updated the effective date for certain non-public companies to annual reporting periods beginning after December 15, 2021. A modified retrospective transition approach is required for capital and operating leases existing at, or entered into after, the beginning of the earliest comparative period presented in the financial statements, or by not adjusting the comparative periods and recording a cumulative effect adjustment as of the adoption date, with certain practical expedients available. The Company, as an Emerging Growth Company as defined by the Jumpstart Our Business Startups Act of 2012 (the "JOBS Act"), can elect to take the extended transition period and adopt the standard following guidance for non-public entities which are a part of the “all other” category. The Company will adopt ASU 2016-02 and all associated amendments on the first day of fiscal 2022 (January 1st, 2022) which includes, as allowed under ASU 2018-11, the ability to recognize a cumulative-effect adjustment through opening retained earnings as of the date of adoption. The Company will elect the package of practical expedients permitted under the transition guidance, which allows the Company to carryforward its historical assessments of: (1) whether contracts are or contain leases, (2) lease classification and (3) initial direct costs. The Company will not elect the hindsight practical expedient. The Company will elect to use the practical expedient that allows the combination of lease and non-lease contract components in all of its underlying asset categories. The Company will also elect a policy of not recording leases on its condensed consolidated balance sheets when the leases have a term of 12 months or less and the Company is not reasonably certain to elect an option to renew the leased asset. The Company is currently evaluating the impact the adoption of this standard will have on its consolidated financial statements. In June 2016, the FASB issued ASU No. 2016-13 —Financial Instruments – Credit Losses (Topic 326) – Measurement of Credit Losses on Financial Instruments. This standard is intended to improve financial reporting by requiring earlier recognition of credit losses on financing receivables and other financial assets in scope, such as trade receivables. The amendment is effective for fiscal years beginning after December 15, 2022. The Company will adopt the update effective January 1, 2023 and does not expect the adoption of the standard to have a material impact on its consolidated financial statements. In December 2019, the FASB issued ASU No. 2019-12— Income Taxes (Topic 740), Simplifying the Accounting for Income Taxes. This standard removes certain exceptions for investments, intra-period allocations and interim tax calculations and adds guidance to reduce complexity in accounting for income taxes. The amendment is effective for fiscal years beginning after December 15, 2021 and early adoption is permitted. The Company is currently evaluating the impact of this update on its consolidated financial position or results of operation. In March 2020, the FASB issued ASU No. 2020-04— Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting . The amendments of ASU No. 2020-04 are effective for companies as of March 12, 2020 through December 31, 2022. An entity may elect to apply the amendments for contract modifications by Topic or Industry Subtopic as of any date from the beginning of an interim period that includes or is subsequent to March 12, 2020, or prospectively from a date within an interim period that includes or is subsequent to March 12, 2020, up to the date that the financial statements are available to be issued. The amendments in this update apply only to contracts, hedging relationships and other transactions that reference LIBOR or another reference rate expected to be discontinued because of reference rate reform and provide optional expedients and exceptions for applying U.S. GAAP to contracts, hedging relationships and other transactions affected by reference rate reform if certain criteria are met. The Company is evaluating the impact that the amendments of this standard would have on its consolidated financial position or results of operations upon adoption.

Business Combinations

Business Combinations	9 Months Ended
Business Combinations	Sep. 30, 2021
Business Combinations [Abstract]
Business Combinations	3. Business Combinations On October 27, 2020, the Company completed the purchase of all outstanding shares of Monocl for a total estimated consideration of $ 46.3 million, and up to $ 60 million, summarized as follows: (in thousands) Cash consideration $ 18,307 Equity issuance 25,439 Contingent consideration 2,600 Purchase price $ 46,346 The assets acquired and liabilities assumed were recorded at their estimated fair values and the results of operations were included in the Company’s consolidated results as of the acquisition date. The contingent consideration performance targets for earnout payments are based on the contractual Annual Recurring Revenue (“ARR”) for each of the twelve-month periods ending December 31, 2020 and December 31, 2021. Potential payouts range from $ 0 to $ 5.0 million and $ 0 to $ 10.0 million based on ARR of below $ 8.5 million to over $ 9.5 million and below $ 12.0 million to over $ 16.0 million for each of the twelve-month periods ending December 31, 2020 and 2021, respectively. The Company estimated the fair value of contingent consideration to be $ 6.9 million and $ 5.2 million at September 30, 2021 and December 31, 2020, respectively, based on the achievement of 2020 ARR targets and the probability of achieving the 2021 targets. Refer to Note 9. Fair Value Measurements for more detail. The purchase accounting for the Monocl acquisition was finalized as of December 31, 2020. The fair values assigned to tangible and identified intangible assets acquired and liabilities assumed were based on management's estimates and assumptions. The final allocation of the acquisition-date fair values of assets and liabilities as of December 31, 2020, was as follows: (in thousands) Preliminary allocation: October 27, Cash $ 2,774 Accounts receivable 788 Prepaid expenses and other current assets 614 Property and equipment 20 Intangible assets 18,900 Accounts payable and accrued expenses ( 2,137 ) Deferred revenue ( 2,884 ) Total assets acquired and liabilities assumed 18,075 Goodwill 28,271 Purchase price $ 46,346 T he Company recorded goodwill, customer relationships, data, technology, and trademark of $ 28.3 million, $ 11.9 million, $ 3.0 million, $ 2.6 million and $ 1.4 million, respectively, as of the acquisition date. The goodwill recognized includes the fair value of the assembled workforce and any expected synergies gained through the acquisition. The Company determined that the goodwill resulting from the acquisition is not deductible for tax purposes. Customer relationships represent the estimated fair value of the underlying relationships with the acquired entity’s business customers and are amortized using the annual pattern of cash flows (economic value method) over the estimated 14-year life of this asset. Data includes proprietary data on medical and scientific expert personnel. The technology recognized includes Monocl’s existing technology and provides users with a cloud-based platform with millions of expert profiles generated using machine learning and tailored algorithms through an online platform. This technology provides the automated collection of content sources, data processing and augmentation, and ultimately the generation of contextually relevant and continuously updated expert profiles. The trademark represents the estimated fair value of the registered trademarks, logo and domain names associated with the Monocl corporate brand. The data, technology, and trademark are amortized using the straight-line method over the estimated remaining useful life of 3 years , 8 years , and 19 years , respectively. In connection with the acquisition, the Company recognized acquisition related costs of $ 0.4 million which were recorded within transaction expenses in the accompanying consolidated statements of income (loss). The results of operations of Monocl are included in the Company’s consolidated results since the date of acquisition. The revenue and net loss of Monocl reflected in the consolidated statements of operations for the year ended December 31, 2020 were $ 1.2 million and $ 1.6 million, respectively. Unaudited Pro Forma Supplementary Data: Nine Months Ended September 30, 2020 (in thousands) Revenue $ 91,750 Net loss ( 43,763 ) The pro forma net loss includes adjustments to amortization expense for the valuation of other intangible assets of $ 0.6 million and interest expense related to incremental borrowings used to finance the transaction of $ 0.8 million and for the nine months ended September 30, 2020. The unaudited pro forma supplementary data is provided for informational purposes only and should not be construed to be indicative of the Company’s results of operations had the acquisition been consummated on the date assumed or of the Company’s results of operations for any future date.

Revenue

Revenue	9 Months Ended
Revenue	Sep. 30, 2021
Revenue From Contract With Customer [Abstract]
Revenue	4. Revenue The Company disaggregates revenue from its arrangements with customers by type of service as it believes these categories best depict how the nature, amount, timing, and uncertainty of revenue and cash flows are affected by economic factors. The following table represents a disaggregation of revenue from arrangements with customers for the three and nine months ended September 30, 2021 and 2020, respectively: Three Months Ended September 30, Nine Months Ended September 30, (in thousands) 2021 2020 2021 2020 Platform subscriptions $ 42,780 $ 29,732 $ 118,545 $ 83,814 Professional services 304 341 1,296 845 Total revenue $ 43,084 $ 30,073 $ 119,841 $ 84,659 The opening and closing balances of the Company’s receivables, deferred contract costs and contract liabilities from contracts with customers are as follows: (in thousands) September 30, December 31, Accounts receivable, net $ 27,886 $ 33,108 Deferred contract costs 5,359 2,947 Long-term deferred contract costs 9,388 5,952 Deferred revenues 70,179 61,200 Deferred Contract Costs A summary of the activity impacting the deferred contract costs for the nine months ended September 30, 2021 and the year ended December 31, 2020 is presented below: (in thousands) September 30, December 31, Balance at beginning of period $ 8,899 $ 2,885 Costs amortized ( 3,195 ) ( 1,670 ) Additional amounts deferred 9,043 7,684 Balance at end of period 14,747 8,899 Classified as: Current 5,359 2,947 Non-current 9,388 5,952 Total deferred contract costs (deferred commissions) $ 14,747 $ 8,899 Contract Liabilities A summary of the activity impacting deferred revenue balances during the nine months ended September 30, 2021 and for the year ended December 31, 2020 is presented below: (in thousands) September 30, December 31, Balance at beginning of period $ 61,200 $ 46,125 Revenue recognized ( 119,841 ) ( 118,317 ) Additional amounts deferred 128,820 133,392 Balance at end of period $ 70,179 $ 61,200 Remaining Performance Obligations ASC 606 introduced the concept of transaction price allocated to the remaining performance obligations of a contract, which is different than unbilled deferred revenue under ASC 605. Transaction price allocated to remaining performance obligations represents contracted revenue that has not yet been recognized, which includes unearned revenue and unbilled amounts that will be recognized as revenue in future periods. Transaction price allocated to remaining performance obligations is influenced by several factors, including seasonality, the timing of renewals, and disparate contract terms. Revenue allocated to remaining performance obligations represents contracted revenue that has not yet been recognized, which includes unearned revenue and backlog. The Company’s backlog represents installment billings for periods beyond the current billing cycle. The majority of the Company’s noncurrent remaining performance obligations will be recognized in the next 13 to 36 months. The remaining performance obligations consisted of the following: (in thousands) September 30, December 31, Current $ 128,653 $ 114,284 Non-current 78,900 58,250 Total $ 207,553 $ 172,534

Accounts Receivable

Accounts Receivable	9 Months Ended
Accounts Receivable	Sep. 30, 2021
Receivables [Abstract]
Accounts Receivable	5. Accounts Receivable Accounts receivable consisted of the following: (in thousands) September 30, December 31, Accounts receivable $ 28,243 $ 33,635 Unbilled receivable 496 329 28,739 33,964 Less: allowance for doubtful accounts ( 853 ) ( 856 ) Accounts receivable, net $ 27,886 $ 33,108

Property and Equipment

Property and Equipment	9 Months Ended
Property and Equipment	Sep. 30, 2021
Property Plant And Equipment [Abstract]
Property and Equipment	6. Property and Equipment Property and equipment consisted of the following: (in thousands) September 30, December 31, Computers and software $ 4,455 $ 3,141 Furniture and equipment 1,580 1,109 Leasehold improvements 2,766 1,781 Construction and software development in process — 128 8,801 6,159 Less: accumulated depreciation and amortization ( 4,104 ) ( 2,911 ) Property and equipment, net $ 4,697 $ 3,248 Depreciation and amortization expense associated with property and equipment was $ 0.5 million and $ 0.3 million for the three months ended September 30, 2021 and 2020, respectively, and $ 1.2 million and $ 0.8 million for the nine months ended September 30, 2021 and 2020 , respectively.

Goodwill and Intangible Assets

Goodwill and Intangible Assets	9 Months Ended
Goodwill and Intangible Assets	Sep. 30, 2021
Goodwill And Intangible Assets Disclosure [Abstract]
Goodwill and Intangible Assets	7. Goodwill and Intangible Assets The carrying amounts of goodwill and intangible assets, as of September 30, 2021 and December 31, 2020, consist of the following: September 30, 2021 (in thousands) Gross Accumulated Net Carrying Finite-lived intangible assets: Customer relationships $ 370,030 $ ( 84,159 ) $ 285,871 Developed technologies 51,100 ( 15,648 ) 35,452 Tradenames 35,500 ( 4,510 ) 30,990 Database 42,656 ( 28,246 ) 14,410 Total finite-lived intangible assets 499,286 ( 132,563 ) 366,723 Goodwill 1,261,444 — 1,261,444 Total goodwill and Intangible assets $ 1,760,730 $ ( 132,563 ) $ 1,628,167 December 31, 2020 (in thousands) Gross Accumulated Net Carrying Finite-lived intangible assets: Customer relationships $ 370,030 $ ( 58,097 ) $ 311,933 Developed technologies 51,100 ( 10,218 ) 40,882 Tradenames 35,500 ( 2,952 ) 32,548 Database 42,656 ( 17,782 ) 24,874 Total finite-lived intangible assets 499,286 ( 89,049 ) 410,237 Goodwill 1,261,444 — 1,261,444 Total goodwill and Intangible assets $ 1,760,730 $ ( 89,049 ) $ 1,671,681 Amortization expense associated with finite-lived intangible assets wa s $ 14.7 m illion and $ 14.6 million for the three months ended September 30, 2021 and 2020, respectively, of which $ 5.4 million and $ 4.8 million was included in cost of revenue for the respective periods. Amortization expense associated with finite-lived intangible assets was $ 43.5 million for both the nine months ended September 30, 2021 and 2020, of which $ 15.9 million and $ 14.3 million was included in cost of revenue for the respective periods. There were no changes to the carrying amount of goodwill in the nine months ended September 30, 2021. The Company determined it had one reporting unit. There was no impairment of goodwill in the nine months ended September 30, 2021 or 2020 .

Long-term Debt

Long-term Debt	9 Months Ended
Long-term Debt	Sep. 30, 2021
Long Term Debt [Abstract]
Long-term Debt	8. Long-Term Debt Long-term debt consisted of the following as of September 30, 2021 and December 31, 2020, respectively: September 30, 2021 (in thousands) Principal Unamortized debt Total debt, 2021 Term Loan $ 275,000 $ ( 2,737 ) $ 272,263 Less: current portion of long-term debt 6,875 Long-term debt $ 265,388 December 31, 2020 (in thousands) Principal Unamortized debt Total debt, 2019 Term Loan $ 444,375 $ ( 10,865 ) $ 433,510 Paid in kind interest on 2019 Term Loan 10,412 — 10,412 2019 Delayed Draw Term Loan 17,955 — 17,955 Total debt $ 472,742 $ ( 10,865 ) $ 461,877 Less: current portion of long-term debt 4,680 Long-term debt $ 457,197 On September 17, 2021, the Company repaid the outstanding principal balances of the 2019 Term Loan, as described below, of $ 442.1 million, paid in kind interest, as described below, of $ 10.4 million, 2019 Delayed Draw Term Loan, as described below, of $ 17.9 million and related accrued interest payable of $ 4.2 million totaling $ 474.6 million using the proceeds from the 2021 Term Loan, as described below, of $ 275.0 million and net proceeds of the IPO of $ 199.6 million, inclusive of accrued interest expense. The effective interest rate for these loans under the 2019 Credit Agreement, as described below, was 6.25 % as of the repayment date. The Company recognized a $ 9.9 million loss on the extinguishment of debt relating to the write off of unamortized debt issuance costs. 2021 Credit Agreement On September 17, 2021, Definitive Healthcare Holdings, LLC, a Delaware limited liability company ("DH Holdings"), an indirect subsidiary of Definitive Healthcare Corp., entered into a credit agreement (the "2021 Credit Agreement") with Bank of America, N.A., as administrative agent, the other lenders party thereto and the other parties specified therein. The 2021 Credit Agreement provides for (i) a $275.0 million term loan A facility (the "2021 Term Loan") and (ii) a $ 75.0 million revolving credit facility (the "2021 Revolving Line of Credit" and, together with the 2021 Term Loan, collectively, the "2021 Credit Facilities"), the proceeds of which were used to repay a portion of the indebtedness outstanding under the 2019 Credit Agreement (as described below). Both the 2021 Term Loan and the 2021 Revolving Line of Credit mature on September 17, 2026 . The 2021 Credit Facilities include customary affirmative, negative and financial covenants. The 2021 Credit Facilities are guaranteed by all of DH Holdings's wholly-owned domestic restricted subsidiaries and AIDH Buyer, LLC, a Delaware limited liability company and the direct parent company of DH Holdings, in each case, subject to customary exceptions, and are secured by a lien on substantially all of the assets of DH Holdings and the guarantors, including a pledge of the equity of DH Holdings, in each case, subject to customary exceptions. The 2021 Term Loan is subject to annual amortization of principal, payable in equal quarterly installments on the last day of each fiscal quarter, commencing on December 31, 2021 (the "Initial Amortization Date"), equal to approximately 2.5% per annum of the principal amount of the term loans in the first year and second year after the Initial Amortization Date and approximately 5.0% per annum of the principal amount of the term loans in the third year, fourth year and fifth year after the Initial Amortization Date. A balloon payment of approximately $ 220.0 million will be due at the maturity of the 2021 Term Loan. There was $ 275.0 mil lion outstanding on the 2021 Term Loan at September 30, 2021. DH Holdings is required to pay the lenders under the 2021 Credit Agreement an unused commitment fee of between 0.25 % and 0.30 % per annum on the undrawn commitments under the 2021 Revolving Line of Credit, depending on the total net leverage ratio, quarterly in arrears. The expense is included in interest expense in the statements of operations. There was no outstanding balance on the 2021 Revolving Line of Credit at September 30, 2021. For both the 2021 Term Loan and 2021 Revolving Line of Credit, DH Holdings may elect from several interest rate options based on the LIBO Rate or the Base Rate plus an applicable margin. The applicable margin will be based on the total leverage ratio beginning in the fiscal year ended December 31, 2022. As of September 30, 2021, the effective interest rate was 2.37 %. In connection with the 2021 Credit Agreement, the Company capitalized financing costs totaling $ 3.5 million, $ 2.8 million for the 2021 Term Loan facility and $ 0.8 million for the 2021 Revolving Line of Credit. The financing costs associated with the 2021 Term Loan facility are recorded as a contra-debt balance in Term loan, net of current portion in the condensed consolidated balance sheets and are amortized over the remaining life of the loan using the effective interest method. The financing costs associated with the 2021 Revolving Line of Credit are recorded in Other assets in the condensed consolidated balance sheet are are amortized over the life of the arrangement. 2019 Credit Agreement On July 16, 2019, DH Holdings entered into a credit agreement (the “2019 Credit Agreement”) by and among DH Holdings, the lenders party thereto and Owl Rock Capital Corporation, as administrative agent. Under the 2019 Credit Agreement, a $ 450.0 million term loan facility (the “2019 Term Loan”), a $ 100.0 million delayed draw term loan facility (the “2019 Delayed Draw Term Loan”) and a $ 25.0 million revolving line of credit (the “2019 Revolving Line of Credit”) were made available to DH Holdings. The 2019 Credit Agreement included customary affirmative, negative and financial covenants. All facilities under the 2019 Credit Agreement were guaranteed, by DH Holdings’s wholly-owned domestic restricted subsidiary, Definitive Healthcare LLC, a Massachusetts limited liability company and AIDH Buyer, LLC, a Delaware limited liability company and the direct parent company of DH Holdings, and were secured by a lien on substantially all of the assets of DH Holdings and the guarantors, including a pledge of the equity of DH Holdings, in each case, subject to customary exceptions. The 2019 Term Loan had a maturity date of July 16, 2026 and was issued with an original issue discount of $ 11.3 million and amortized to interest expense over the term of the agreement using the effective interest method. Interest on a portion of the loan ($ 100.0 million of the $ 450.0 million principal amount) was treated as paid in kind and added to the principal balance to be paid off at maturity. DH Holdings could elect from several interest rate options based on the Eurodollar Rate or the Base Rate plus an applicable margin. Quarterly principal payments of $ 1.1 million began in December 2019 and were required through the 2019 Term Loan's maturity, at which time a balloon payment of $ 419.6 million, excluding the paid in kind portion, was due. The paid in kind interest was payable on the maturity date. 2019 Term Loan was subject to excess cash flow payments annually beginning in the fiscal year ended December 31, 2020 based on the total leverage ratio. There was $ 454.8 million outstanding on the 2019 Term Loan at December 31, 2020, including $ 10.4 million of paid in kind interest. The effective interest rate for the 2019 Term Loan and paid in kind effective interest was 6.50 % at December 31, 2020. The 2019 Delayed Draw Term Loan had a maturity of July 16, 2026 . The 2019 Delayed Draw Term Loan was issued with an original issue discount of $ 1.3 million. DH Holdings could draw down funds under the 2019 Delayed Draw Term Loan until July 16, 2021. As of December 31, 2020, DH Holdings drew $ 18.0 million on the 2019 Delayed Draw Term Loan, in connection with the Monocl acquisition. DH Holdings could elect from several interest rate options based on the Eurodollar Rate or the Base Rate plus an applicable margin. Quarterly in arrears through July 16, 2021, DH Holdings was required to pay the bank a fee equal to 1 % per annum of the amount of the 2019 Delayed Draw Term Loan unused capacity. Quarterly principal payments began in December 2020 in quarterly installments equal to 0.25 % of the aggregate amount outstanding on the 2019 Delayed Draw Term Loan, and are required through the note’s maturity, at which time a payment of the entire outstanding principal balance will be due. The outstanding balance on the 2019 Delayed Draw Term Loan was $ 18.0 million at December 31, 2020. The effective interest rate for the 2019 Delayed Draw Term Loan was 6.50 % at December 31, 2020. The 2019 Revolving Line of Credit had a maturity of July 16, 2024 . DH Holdings could elect from several interest rate options based on the Eurodollar Rate or the Base Rate plus an applicable margin. During 2020, $ 25.0 million was drawn on the 2019 Revolving Line of Credit and subsequently paid back in 2020. There was no outstanding balance on the 2019 Revolving Line of Credit at December 31, 2020. No draws on the 2019 Revolving Line of Credit were made in 2021 and the 2019 Credit Agreement was terminated on September 17, 2021 . In connection with the 2019 Credit Agreement, the Company originally capitalized financing costs totaling $ 14.1 million, $ 13.4 million for the 2019 Term Loan and $ 0.7 million for the 2019 Revolving Line of Credit. In October 2020, the Company capitalized an additional $ 0.2 million in financing costs associated with the 2019 Delayed Draw Term Loan borrowing. These financing costs were recorded as deferred financing costs in the condensed consolidated balance sheets and amortized over the remaining lives of the respective borrowing using the effective interest method. The Company expensed capitalized financing costs for the 2019 Credit Agreement through interest expense of $ 0.4 million and $ 0.5 million for the three months ended September 30, 2021 and 2020, respectively, and $ 1.5 million for the nine months ended September 30, 2021 and 2020, respectively. At December 31, 2020, the unamortized financing costs for the 2019 Revolving Line of Credit of $ 0.5 million was classified in other assets in the consolidated balance sheet.

Fair Value Measurements

Fair Value Measurements	9 Months Ended
Fair Value Measurements	Sep. 30, 2021
Fair Value Disclosures [Abstract]
Fair Value Measurements	9. Fair Value Measurements ASC 820, Fair Value Measurements and Disclosures (“ASC 820”), defines fair value as the price that would be received for an asset, or paid to transfer a liability, in an orderly transaction between market participants on the measurement date, and establishes a three-level fair value hierarchy that prioritizes the inputs used to measure fair value. The Company’s financial assets and liabilities subject to the three-level fair value hierarchy consist principally of cash and equivalents, accounts receivable, accounts payable, long-term and short-term debt and contingent consideration payable. The estimated fair value of cash and equivalents, accounts receivable and accounts payable approximates their carrying value due to due to their short maturities (less than 12 months). The Company’s short- and long-term debt are recorded at their carrying values in the consolidated balance sheets, which may differ from their respective fair values. The carrying values and estimated fair values of the Company’s short- and long-term debt approximate their carrying values as of December 31, 2020, and 2019, based on interest rates currently available to the Company for similar borrowings. The contingent consideration, which resulted from the earn-outs associated with the Monocl acquisition, is measured at fair value on a recurring basis. The fair value was estimated using a variation of the income approach, known as the real options method, where ARR was simulated in a risk-neutral framework using Geometric Brownian Motion, a well-accepted model of stock price behavior that is used in option pricing models such as the Black-Scholes option pricing model. The risk-neutral expected (probability-weighted) earnout payments were then calculated based on simulation results. An increase to a probability of achievement would result in a higher fair value measurement. At September 30, 2021 and December 31, 2020, the fair value of the contingent consideration was estimated at $ 6.9 mi llion and $ 5.2 million, respectively. The current portion of the earn-out liability ($ 6.9 m illion and $ 1.5 million at September 30, 2021 and December 31, 2020, respectively) is included in accrued expenses and other current liabilities on the consolidated balance sheets, and the non-current portion ( nil at September 30, 2021 and $ 3.7 million at December 31, 2020) in other long-term liabilities. A payment of $ 1.5 million was made in April 2021. Earn-out liabilities are classified within Level 3 in the fair value hierarchy because the methodology used to develop the estimated fair value includes significant unobservable inputs reflecting management’s own assumptions. The valuation techniques and significant unobservable inputs used in recurring Level 3 fair value measurements were as follows as of September 30, 2021 and December 31, 2020: (in thousands) Fair Value Valuation Technique Unobservable Discount Rate Earn-out liabilities $ 6,905 Income Approach (Real Option Method) Discount rate 2.38 % The table below presents a reconciliation of earnout liabilities measured at fair value on a recurring basis using significant unobservable inputs (Level 3): (in thousands) September 30, December 31, Balance at beginning of period $ 5,236 $ — Additions — 2,600 Net change in fair value and other adjustments 3,169 2,636 Payments ( 1,500 ) — Balance at end of period $ 6,905 $ 5,236 Adjustments to the earn-out liabilities in periods subsequent to the completion of acquisitions were made using scenario-based modeling to estimate the probability of achievement and are reflected within transaction expenses in the condensed consolidated statements of operations. As of September 30, 2021, the Company had the potent ial to make a maximum of $ 10.0 million and a minimum of $ 0.0 million (undiscounted) in earn-out payments. Assuming the ach ievement of the applicable performance criteria, these earn-out payments will be made in April 2022. Certain assets and liabilities, including property, plant and equipment, goodwill and other intangible assets, are measured at fair value on a non-recurring basis. These assets are remeasured when the derived fair value is below the carrying value on the Company’s consolidated balance sheet. For these assets, the Company does not periodically adjust carrying value to fair value except in the event of impairment. When impairment has occurred, the Company measures the required charges and adjusts the carrying value as discussed in Note 2. Summary of Significant Accounting Policies of the Notes to the Consolidated Financial Statements in the Company’s IPO Prospectus.

Accrued Expenses and Other Curr

Accrued Expenses and Other Current Liabilities	9 Months Ended
Accrued Expenses and Other Current Liabilities	Sep. 30, 2021
Accounts Payable And Accrued Liabilities Current [Abstract]
Accrued Expenses and Other Current Liabilities	10. Accrued Expenses and Other Current Liabilities Accrued expenses and other current liabilities consisted of the following: (in thousands) September 30, December 31, Payroll and payroll-related $ 7,246 $ 7,792 Accrued interest 233 5,365 Contingent consideration, current 6,905 1,500 Sales taxes 1,146 649 Deferred rent 112 583 Other 3,654 1,432 Accrued expenses and other current liabilities $ 19,296 $ 17,321

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
Commitments and Contingencies	Sep. 30, 2021
Commitments And Contingencies Disclosure [Abstract]
Commitments and Contingencies	11. Commitments and Contingencies The Company leases office facilities in Massachusetts, Vermont and Sweden, the terms of which expire at various times through the year 2030. In 2019, the Company signed a new office lease agreement which commenced in 2020 and will continue through 2027. Total rent expense for the three and nine months ended September 30, 2021 was $ 0.7 million and $ 2.1 million, respectively, and rent expense for the three and nine months ended September 30, 2020 was $ 0.5 million and $ 1.4 million, respectively. Rent expense was classified in selling, general, and administrative expense in the condensed consolidated statements of operations for all periods presented.

Stockholders' Equity and Member

Stockholders' Equity and Members' Equity	9 Months Ended
Stockholders' Equity and Members' Equity	Sep. 30, 2021
Members Equity [Abstract]
Stockholders' Equity and Members' Equity	12. Stockholders' Equity and Members' Equity The Company has Class A Common Stock, Class B Common Stock and Preferred Stock. Holders of outstanding shares of Class A Common Stock and Class B Common Stock will vote as a single class on all matters on which stockholders are entitled to vote generally, except as otherwise required by law. Class B Common Stock issued to holders of Definitive OpCo Units that are unvested shall have no vote per share until such time as such Units have vested. Class A Common Stockholders are entitled to receive dividends, if declared by our board of directors out of legally available funds. Upon our liquidation, dissolution or winding up and after payment in full of all amounts required to be paid to creditors and to the holders of Preferred Stock having liquidation preferences, if any, the holders of shares of our Class A Common Stock will be entitled to receive pro rata our remaining assets available for distribution. Class B Common Stockholders are not entitled to economic interests in Definitive Healthcare Corp. and do not have any right to receive dividends or to receive a distribution upon a liquidation or winding up of Definitive Healthcare Corp. Shares of Preferred Stock have no t been issued at September 30, 2021. The board of directors may authorize one or more series of Preferred Stock (including convertible Preferred Stock) and will determine, with respect to any series of Preferred Stock, the voting rights, preferences, participation, or other special rights and limitations. Under the Amended Definitive OpCo LLC Agreement, the holders of LLC Units have the right to require Definitive OpCo to exchange all or a portion of their LLC Units for newly issued shares of Class A Common Stock, which may consist of unregistered shares, on a one-for-one basis (subject to customary adjustments, including for stock splits, stock dividends and reclassifications). Shares of Class B Common Stock and their corresponding LLC Units will be canceled on a one-for-one basis once an exchange has been completed. As described in Note 1. Description of Business , the Company was formed by Advent International ("Advent") for the purpose of acquiring Definitive Holdco. Upon formation of the Company, two classes of units were established: Class A Units (“Class A Units”) and Class B Units (“Class B Units”), collectively "the Units". The table below provides a summary of the number of Class A and Class B units authorized, issued and outstanding as of December 31, 2020, respectively. December 31, Class A units: Authorized, issued and outstanding Class A units 130,245,990 Class B units: Authorized Class B units 8,088,877 Issued Class B units 3,720,063 Outstanding Class B units (Vested Class B units) 474,920 During 2021, the Company issued 363,516 new Class A units worth $ 5.8 million, consisting of a capital contribution of $ 5.5 million and equity-based compensation expense of $ 0.3 million. Refer to Note 13. Equity-Based Compensation for more detail on Class B units.

Equity-Based Compensation

Equity-Based Compensation	9 Months Ended
Equity-Based Compensation	Sep. 30, 2021
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Equity-Based Compensation	13. Equity-Based Compensation Equity-based compensation expense is allocated to all departments in the accompanying condensed consolidated statements of operations based on the recipients of the compensation. A summary of the expense by line item in the consolidated statements of operations for the three and nine months ended September 30, 2021 and 2020, respectively, is provided in the following table. Three Months Ended September 30, Nine Months Ended September 30, (in thousands) 2021 2020 2021 2020 Cost of revenue $ 48 $ 16 $ 79 $ 46 Sales and marketing 326 132 567 380 Product development 187 93 341 267 General and administrative 1,756 217 3,351 637 Total compensation expense $ 2,317 $ 458 $ 4,338 $ 1,330 2021 Equity Incentive Plan As of September 15, 2021, in connection with its IPO, the Company adopted the Definitive Healthcare Corp. 2021 Equity Incentive Plan (the "2021 Plan"). The types of grants available under the 2021 Plan include stock options (both incentive and non-qualified), stock appreciation rights ("SARs"), restricted stock awards ("RSAs"), restricted stock units ("RSUs"), and stock-based awards. The aggregate number of shares of Class A Common Stock available for grant under the 2021 Plan was 8,989,039 shares at September 30, 2021. As of September 30, 2021, 1,464,681 RSUs have been granted under the 2021 Plan. The outstanding RSUs have time-based and/or performance-based vesting criteria. Outstanding time-based RSUs generally vest partially on the one year anniversary of each grant and quarterly over the subsequent two- or three-year period. Outstanding performance-based RSUs vest annually over three years upon the achievement of certain performance targets and continued service, the measurement period for which begins January 1, 2022. As such, no stock-based compensation expense associated with performance-based RSUs was recorded in the third quarter of 2021. The following table summarizes the Company’s unvested time-based and performance-based RSU activity for the nine months ended September 30, 2021. Time-Based Performance-Based Weighted Weighted Restricted Average Grant Restricted Average Grant Stock Units Date Fair Value Stock Units Date Fair Value Unvested at beginning of period — $ - — $ - Granted 1,300,328 $ 27.00 164,353 $ 27.00 Vested — $ - — $ - Forfeited ( 2,656 ) $ 27.00 — $ - Unvested at end of period 1,297,672 $ 27.00 164,353 $ 27.00 The Company recognized $ 0.4 million in stock-based compensation expense associated with RSUs granted in 2021. Total unrecognized expense was estimated to be $ 39.1 million for both time-based vesting and performance-based vesting awards at September 30, 2021, to be recognized over a weighted-average period of approximately 4.0 years . 2019 Equity Incentive Plan In July 2019, the Company and its Board of Members approved the 2019 Equity Incentive Plan ("the 2019 Plan") under which the Parent Company had reserved approximately 8,088,877 Class B Units (the “2019 Incentive Equity Pool”). The 2019 Incentive Equity Pool was utilized for the issuance of units to employees, consultants, directors, managers, or others providing services to the Company pursuant to Board of Members approval. These interests were considered profit interests, which, in general, entitle the holder of the unit to a pro rata share of the increase in value of the unit over the base value determined at the award date and were subject to such vesting and other restrictions as the Board of Members deemed appropriate. Any units forfeited or repurchased were available for future grants under the 2019 Incentive Equity Pool. The units had time-based and/or performance-based vesting criteria. Generally, the time-based units vested in equal annual installments over a four-year period on the anniversary date of the vest date. The performance-based units vested based on the achievement of specified returns on investments upon a change of control or qualifying event, as defined in the agreement. In connection with the IPO, performance-based forfeiture conditions for unvested units were waived through a modification of the awards and, after the IPO, all such unvested awards became subjected to time-vesting over three years from the IPO Date. As a result of the modification of the terms of such performance-vesting awards, we recorded compensation expense based on the fair value of the units that otherwise would have been forfeited, using the IPO price of $ 27.00 per share. The total compensation expense related to modification was $ 9.0 million, which will be recognized over the respective remaining service periods. The Company recorded $ 0.2 million in stock-based compensation expense associated with these performance-vesting units in the third quarter of 2021. In connection with the retirement of an executive officer, the Company accelerated the vesting of 24,049 unvested time-vesting Class B units and 48,099 of his unvested performance-vesting Class B units. The Company recorded incremental compensation expense of approximately $ 1.9 million during the third quarter 2021. Upon separation, the remaining 72,149 in Class B units were forfeited. Effective September 15, 2021, the Company will no longer grant any awards under the 2019 Plan, though previously granted awards under the 2019 Plan remain outstanding and governed by the 2019 Plan, except for the modifications discussed above. For awards granted in the 2019 Plan, the Company assessed the fair value of the awards as of the grant date. The fair value of the units was estimated using a two-step process. First, the Company’s enterprise value was established using generally accepted valuation methodologies, including discounted cash flow analysis, guideline comparable public company analysis, and comparable transaction method. Second, the enterprise value was allocated among the securities that comprise the capital structure of the Company using an option-pricing method based on the Black-Scholes model. For performance-based units, the Company used a Monte Carlo simulation analysis, which captures the impact of the performance vesting conditions to value the performance-based units. The use of the Black-Scholes model and the Monte Carlo simulation requires the Company to make estimates and assumptions, such as expected volatility, expected term and expected risk-free interest rate. Significant assumptions used to estimate the fair value of units were as follows, which were the same between service-based and performance-based shares: September 15, 2021 December 31, 2020 Expected option term 0.30 - 0.70 years 5.5 years Risk-free rate of return 0.01 % - 0.06 % 1.73 % Applied volatility 30 % 35 % In connection with the Reorganization Transactions and the IPO, unvested Class B Units held directly by employees of the Company or indirectly through Definitive OpCo, were exchanged for unvested Definitive OpCo units based on their respective participation thresholds and the IPO price of $27.00 per share. The time-based units issued upon the exchange remain subject to the same service vesting requirements as the original Class B Units. The pre-IPO performance-based units were exchanged for time-based units and will vest over a three-year period beginning on the date of the IPO. The following table summarizes the Company’s unvested time-based and performance-based unit activity from January 1, 2021 through September 30, 2021. Time-Based Performance-Based Weighted Weighted Non-Vested Average Grant Non-Vested Average Grant Units Date Fair Value Units Date Fair Value Non-vested at December 31, 2020 1,404,720 $ 3.65 1,840,423 $ 2.35 Granted 1,477,323 1.41 1,177,308 0.41 Vested ( 437,731 ) 3.64 — — Forfeited ( 13,770 ) 3.65 ( 18,361 ) 2.35 Non-vested at September 15, 2021 2,430,542 $ 2.29 2,999,370 $ 1.59 Effect of Reorganization Transactions and IPO ( 1,165,679 ) 2.08 ( 1,318,171 ) 1.39 Performance-based units exchanged for time-based units 1,681,199 1.74 ( 1,681,199 ) 1.74 Vested ( 74,049 ) 2.75 — — Forfeited ( 72,149 ) 2.78 — — Non-vested at September 30, 2021 2,799,864 $ 2.02 — $ — In connection with the Reorganization Transactions and the IPO, 912,651 vested Class B Units held directly by employees of the Company or indirectly through Definitive OpCo were exchanged into 578,217 vested Definitive OpCo units based on their respective participation thresholds and the IPO price of $27.00 per share. The Company recorded $0.6 million and $1.5 million in stock-based compensation expense associated with time-based units in the three and nine months ended September 30, 2021, respectively. The Company recorded $0.5 million and $1.3 million in stock-based compensation expense associated with unexchanged time-based units in the three and nine months ended September 30, 2020, respectively. At September 30, 2021, the Company had approximately $ 18.4 million of unrecognized unit-based compensation expense for unvested time-based units, including those that were exchanged for time-based units at IPO. The expense, which will be recorded under the terms of the 2019 Plan, is expected to be recognized over a weighted-average period of approximately 2.8 years.

Retirement Plans

Retirement Plans	9 Months Ended
Retirement Plans	Sep. 30, 2021
Compensation And Retirement Disclosure [Abstract]
Retirement Plans	14. Retirement Plan The Company has a 401(k) plan covering all employees who have met certain eligibility requirements. The Company incurred $ 0.6 million and $ 1.7 million in employer matching contributions during the three and nine months ended September 30, 2021 , respectively, and $ 0.4 million and $ 1.1 million during the three and nine months ended September 30, 2020 , respectively .

Income Taxes

Income Taxes	9 Months Ended
Income Taxes	Sep. 30, 2021
Income Tax Disclosure [Abstract]
Income Taxes	15. Income Taxes As described in Note 1. Business Organization and Note 12. Stockholders' Equity and Members' Equity , as a result of the IPO, Definitive Healthcare Corp. began consolidating the financial results of Definitive OpCo. Definitive OpCo is treated as a partnership for U.S. federal and most applicable state and local income tax purposes. As a partnership, Definitive OpCo is not subject to U.S. federal and certain state and local income taxes. Any taxable income or loss generated by Definitive OpCo is passed through to and included in the taxable income or loss of its members, including Definitive Healthcare Corp., based on its economic interest held in Definitive OpCo. Definitive Healthcare Corp. was formed on May 5, 2021 and did not engage in any operations prior to the IPO. Definitive Healthcare Corp. is taxed as a corporation and is subject to U.S. federal, state, and local income taxes with respect to its allocable share of any taxable income or loss of Definitive OpCo, as well as such taxes on any stand-alone income or loss generated by Definitive Healthcare Corp. The Company has recorded an immaterial amount of tax expense associated with corporations owned by Definitive OpCo within general and administrative expense. As of September 30, 2021, management performed an assessment of the recoverability of deferred tax assets. Management determined, based on the accounting standards applicable to such assessment, that sufficient negative evidence to conclude it was more likely than not that its deferred tax assets would not be realized and has recorded a valuation allowance against substantially all of its deferred tax assets. In the event that management determines the Company would be able to realize its deferred tax assets in the future in excess of their net recorded amount, an adjustment to the valuation allowance would be made which would reduce the provision for income taxes. As of September 30, 2021 the Company has a net deferred tax liability of $ 71.3 million which was recorded through equity as part of the Reorganization Transactions. The net deferred tax liability principally relates to taxable temporary differences that cannot be considered a source of income to recover the deferred tax assets due to attribute limitation rules. The Company recognizes uncertain income tax positions when it is more-likely-than-not the position will be sustained upon examination. As of September 30, 2021 and December 31, 2020, the Company has no t identified any uncertain tax positions and has not recognized any related reserves. The Company's effective tax rate was ( 0.3 )% and 0.0 % for the three months ended September 30, 2021 and 2020, respectively, and ( 0.3 )% and 0.0 % for the nine months ended September 30, 2021 and 2020, respectively. Tax Receivable Agreement Pursuant to the Company's election under Section 754 of the Internal Revenue Code (the "Code"), the Company expects to obtain an increase in its share of the tax basis in the net assets of Definitive OpCo when LLC Interests are redeemed or exchanged by other members. The Company plans to make an election under Section 754 of the Code for each taxable year in which a redemption of exchange of LLC Interest occurs. The Company intends to treat any redemptions and exchanges of LLC Interest as direct purchases of LLC Interests for U.S. federal income tax purposes. These increases in tax basis may reduce the amounts that would otherwise be paid in the future to various tax authorities. They may also decrease gains (or increase losses) on future dispositions of certain assets to the extent tax basis is allocated to those assets. In connection with the IPO, the Company entered into a Tax Receivable Agreement ("TRA") and recorded a liability under the TRA of $ 146.1 million as of September 30, 2021 through equity as part of the Reorganization Transactions. Under the TRA, the Company generally will be required to pay certain of our pre-IPO owners 85 % of the amount of cash savings, if any, in U.S. federal, state, or local tax that the Company actually realizes directly or indirectly (or is deemed to realize in certain circumstances) as a result of (i) certain tax attributes created as a result of any sales or exchanges (as determined for U.S. federal income tax purposes) to or with the Company of their interests in Definitive OpCo, including any basis adjustment relating to the assets of Definitive OpCo, (ii) certain favorable tax attributes acquired by the Company from the Blocker Companies in the Reorganization Transactions (including net operating losses and the unamortized portion of the increase in tax basis in the tangible and intangible assets of Definitive OpCo resulting from the prior acquisitions of interests in Definitive OpCo by the Blocker Companies), and (iii) tax benefits attributable to payments made under the TRA. The Company expects to benefit from the remaining 15 % of any tax benefits that it may realize. To the extent that the Company is unable to timely make payments under the TRA for any reason, such payments generally will be deferred and will accrue interest until paid. No amounts are expected to be paid within the next 12 months.

Loss Per Share

Loss Per Share	9 Months Ended
Loss Per Share	Sep. 30, 2021
Earnings Per Share [Abstract]
Loss Per Share	16. Loss Per Share Basic net loss per share of Class A Common Stock is computed by dividing net income attributable to Definitive Healthcare Corp. by the weighted-average number of shares of Class A Common Stock outstanding during the period, excluding unvested equity awards and subsidiary member units not exchanged. Diluted earnings per share of Class A Common Stock is calculated by dividing net income attributable to Definitive Healthcare Corp, adjusted for the assumed exchange of all potentially dilutive securities by the weighted-average number of shares of Class A Common Stock outstanding. Prior to the IPO, the Definitive OpCo membership structure included Class A and Class B member units. The Company analyzed the calculation of earnings per unit for periods prior to the IPO and determined that it resulted in values that would not be meaningful to the users of these unaudited consolidated financial statements. Therefore, earnings per share information has not been presented for the three and nine months ended September 30, 2020. The following table sets forth reconciliations of the numerators and denominators used to compute basic and diluted net loss per share of Class A Common Stock for the three- and nine-months ended September 30, 2021. The basic and diluted earnings per share for the three- and nine-months ended September 30, 2021 reflects only the period from September 15, 2021 to September 30, 2021, which represents the period wherein the Company had outstanding Class A Common Stock. (in thousands) Three Months Nine Months Numerator: Net loss $ ( 20,966 ) $ ( 46,493 ) Less: Net loss attributable to Definitive OpCo before Reorganization Transactions ( 7,816 ) ( 33,343 ) Less: Net loss attributable to noncontrolling interests ( 5,172 ) ( 5,172 ) Net loss attributable to Definitive Healthcare Corp. $ ( 7,978 ) $ ( 7,978 ) The following table sets forth the computation of basic and diluted net loss per share of Class A Common Stock (per share amounts unaudited): (in thousands, except number of shares and per share amounts) Three Months Nine Months Basic net loss per share attributable to common stockholders Numerator: Allocation of net loss attributable to Definitive Healthcare Corp. $ ( 7,978 ) $ ( 7,978 ) Weighted average number of shares of Class A outstanding 88,263,333 88,263,333 Net loss per share, basic and diluted $ ( 0.09 ) $ ( 0.09 ) Shares of the Company’s Class B Common Stock do not participate in the earnings or losses of Definitive Healthcare Corp. and are therefore not participating securities. As such, separate presentation of basic and diluted earnings per share of Class B Common Stock under the two-class method has not been presented. The following table presents potentially dilutive securities excluded from the computation of diluted net loss per share for the period presented because their effect would have been anti-dilutive: Nine Months Definitive OpCo Units 57,192,893

Segment and Geographic Data

Segment and Geographic Data	9 Months Ended
Segment and Geographic Data	Sep. 30, 2021
Segment Reporting [Abstract]
Segment and Geographic Data	17. Segment and Geographic Data The Company operates as one operating segment. Operating segments are defined as components of the Company for which separate financial information is available and evaluated regularly by the Company’s chief operating decision maker in deciding how to allocate resources and in assessing performance. The chief operating decision maker for the Company is the chief executive officer. The chief executive officer reviews financial information presented on a consolidated basis, accompanied by information about revenue by type of service and geographic region, for purposes of allocating resources and evaluating financial performance. Revenues by geographic area presented based upon the location of the customer are as follows: For the Three Months Ended September 30, For the Nine Months Ended September 30, (in thousands) 2021 2020 2021 2020 United States $ 40,863 $ 30,073 $ 114,339 $ 84,659 Rest of world 2,221 — 5,502 — Total revenues $ 43,084 $ 30,073 $ 119,841 $ 84,659 For a summary of our revenue disaggregated by service, refer to Note 4. Revenue . Long-lived assets by geographical region are based on the location of the legal entity that owns the assets. Long-lived assets by geographic area presented based upon the location of the assets are as follows: (in thousands) September 30, December 31, United States $ 4,311 $ 3,120 Rest of world 386 128 Total long-lived assets $ 4,697 $ 3,248

Related Parties

Related Parties	9 Months Ended
Related Parties	Sep. 30, 2021
Related Party Transactions [Abstract]
Related Parties	18. Related Parties The Company has engaged in revenue transactions within the ordinary course of business with entities affiliated with its private equity sponsors and with members of the Company’s board of directors. During each of the nine months ended September 30, 2021 and 2020 the Company recorded revenue of $ 0.7 million and $ 0.6 m illion, respectively. The associated receivable for the revenue transactions amounted to $ 0.1 million and $ 0.7 million at September 30, 2021 and December 31, 2020, respectively. The Company reimburses its private equity sponsors for services and any related travel and out-of-pocket expenses. During the nine months ended September 30, 2021, the Company had expenses for services, travel and out-of-pocket expenses to its private equity sponsor s of $ 0.2 million and was no t material for the nine months ended September 30, 2020. The associated payable for the service transactions was no t material at September 30, 20 21 and December 31, 2020. On September 17, 2021, Definitive OpCo entered into an agreement to reim burse approximately $ 0.9 million in aggregate documented expenses incurred by Advent International, 22C Capital LLC ("22C Capital"), Spectrum Equity Management, L.P. ("Spectrum Equity"), Jason Krantz and MHDH AB and in connection with the Reorganization Transactions. The amounts were included in accrued expenses and other current liabilities as of September 30, 2021 and are expected to be paid in the fourth quarter of 2021. During the second quarter of 2021, the Company issued 363,516 new Class A units wo rth $ 5.8 million to members of the Company's board of directors. Further, in connection with Definitive Healthcare’s IPO, the underwriters reserved 5 % of the common shares for sale at the initial offering price to the Company’s directors, officers and selected senior managers (the “Directed Share Program”). Richard Booth and Samuel A. Hamood participated in the Directed Share Program and purchased 7,407 and 37,037 shares of Class A Common Stock, respectively.

Noncontrolling Interest

Noncontrolling Interest	9 Months Ended
Noncontrolling Interest	Sep. 30, 2021
Noncontrolling Interest [Abstract]
Noncontrolling Interest	19. Noncontrolling Interest Definitive Healthcare Corp. operates and controls all of the business and affairs of Definitive OpCo, and through Definitive OpCo and its subsidiaries, conducts its business. Accordingly, Definitive Healthcare Corp. consolidates the financial results of Definitive OpCo, and reports the noncontrolling interests of its consolidated subsidiaries on its consolidated financial statements based on the Definitive OpCo Units held by Continuing LLC Members. Changes in Definitive Healthcare Corp.'s ownership interest in its consolidated subsidiaries are accounted for as equity transactions. As such, future redemptions or direct exchanges of OpCo Units by Continuing LLC Members will result in a change in ownership and reduce or increase the amount recorded as Noncontrolling interests and increase or decrease Additional paid-in capital in the Company’s Condensed Consolidated Balance Sheets. As of September 30, 2021, Definitive Healthcare Corp. held 88,263,333 units in the Definitive OpCo resulting in an ownership interest of 60.7 % .

Subsequent Events

Subsequent Events	9 Months Ended
Subsequent Events	Sep. 30, 2021
Subsequent Events [Abstract]
Subsequent Events	. Subsequent Events Robert Musslewhite was appointed as President of Definitive Healthcare Corp. effective October 7, 2021. In connection with his appointment, Mr. Musslewhite entered into an employment agreement pursuant to which, he will be paid an annual base salary of $ 0.4 million. Mr. Musslewhite's annual bonus will equal 68% of his pro-rated base salary calculated from the effective date of his employment agreement. In future years, Mr. Musslewhite will be eligible to receive an annual bonus of up to 68 % of his base salary, determined in the sole discretion of the Board, and will be able to participate in the Company's exective incentive plan on the same terms as similarly situated executives. In addition, pursuant to his employment agreement, Mr. Musslewhite will be granted a restricted stock unit award of 433,550 shares of the Company's Class A common stock, which will vest 25 % on the one-year anniversary of the grant, followed by quarterly vesting of 6.25 % per quarter until fully vested over the subsequent three years. Further, Mr. Musslewhite will be granted a second restricted stock unit award in the amount of 216,450 shares of Class A common stock, 33 % of which will vest on the one-year anniversary of the grant, followed by quarterly vesting of 8.33 % per quarter until fully vested over the subsequent two years.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	9 Months Ended
Summary of Significant Accounting Policies (Policies)	Sep. 30, 2021
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States (“GAAP”) and in conformity with rules applicable to quarterly financial information. The Financial Accounting Standards Board (“FASB”) establishes these principles to ensure financial condition, results of operations, and cash flows are consistently reported. Any reference in these notes to applicable accounting guidance is meant to refer to the authoritative nongovernmental GAAP as found in the FASB Accounting Standards Codification (“ASC”). The condensed consolidated financial statements as of September 30, 2021 and for the three and nine months ended September 30, 2021 and 2020 are unaudited. Amounts for the period from January 1, 2020 through September 15, 2021 presented in the condensed consolidated financial statements and notes to the condensed consolidated financial statements herein represent the historical operations of Definitive OpCo. The amounts as of September 30, 2021 and for the period from September 16, 2021 reflect the consolidated operations of Definitive Healthcare Corp. and its consolidated subsidiaries. All adjustments, consisting of normal recurring adjustments, except as otherwise noted, considered necessary for a fair presentation of the unaudited interim condensed consolidated financial statements for these interim periods have been included. Refer to Note 2. Summary of Significant Accounting Policies of the Notes to the Consolidated Financial Statements in the Company’s final prospectus dated September 14, 2021 filed with the Securities and Exchange Commission ("SEC") pursuant to Rule 424(b) of the Securities Act of 1933, as amended, on September 16, 2021 (the "IPO Prospectus") for the Company’s accounting policies and estimates.
Adoption of Recently Issued Financial Accounting Standards	Adoption of Recently Issued Financial Accounting Standards In August 2018, the FASB issued ASU No. 2018-15— Intangibles — Goodwill and Other — Internal-Use Software (Subtopic 350-40), Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract . This standard aligns the requirements for capitalizing implementation costs incurred in a hosting arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software. The amendment is effective for fiscal years beginning after December 15, 2020 and early adoption is permitted. The Company adopted the update effective January 1, 2021. The adoption did not have a material impact on the consolidated financial statements. Recently-Issued Accounting Pronouncements Not Yet Adopted In February 2016, the FASB issued ASU 2016-02— Leases . The new standard establishes a right-of-use (“ROU”) model that requires a lessee to record a ROU asset and a lease liability on the balance sheet for all leases with terms longer than twelve months. Leases will be classified as either finance or operating, with classification affecting the pattern of expense recognition in the income statement. The FASB has subsequently issued supplemental and/or clarifying ASUs inclusive of ASU 2020-05, which updated the effective date for certain non-public companies to annual reporting periods beginning after December 15, 2021. A modified retrospective transition approach is required for capital and operating leases existing at, or entered into after, the beginning of the earliest comparative period presented in the financial statements, or by not adjusting the comparative periods and recording a cumulative effect adjustment as of the adoption date, with certain practical expedients available. The Company, as an Emerging Growth Company as defined by the Jumpstart Our Business Startups Act of 2012 (the "JOBS Act"), can elect to take the extended transition period and adopt the standard following guidance for non-public entities which are a part of the “all other” category. The Company will adopt ASU 2016-02 and all associated amendments on the first day of fiscal 2022 (January 1st, 2022) which includes, as allowed under ASU 2018-11, the ability to recognize a cumulative-effect adjustment through opening retained earnings as of the date of adoption. The Company will elect the package of practical expedients permitted under the transition guidance, which allows the Company to carryforward its historical assessments of: (1) whether contracts are or contain leases, (2) lease classification and (3) initial direct costs. The Company will not elect the hindsight practical expedient. The Company will elect to use the practical expedient that allows the combination of lease and non-lease contract components in all of its underlying asset categories. The Company will also elect a policy of not recording leases on its condensed consolidated balance sheets when the leases have a term of 12 months or less and the Company is not reasonably certain to elect an option to renew the leased asset. The Company is currently evaluating the impact the adoption of this standard will have on its consolidated financial statements. In June 2016, the FASB issued ASU No. 2016-13 —Financial Instruments – Credit Losses (Topic 326) – Measurement of Credit Losses on Financial Instruments. This standard is intended to improve financial reporting by requiring earlier recognition of credit losses on financing receivables and other financial assets in scope, such as trade receivables. The amendment is effective for fiscal years beginning after December 15, 2022. The Company will adopt the update effective January 1, 2023 and does not expect the adoption of the standard to have a material impact on its consolidated financial statements. In December 2019, the FASB issued ASU No. 2019-12— Income Taxes (Topic 740), Simplifying the Accounting for Income Taxes. This standard removes certain exceptions for investments, intra-period allocations and interim tax calculations and adds guidance to reduce complexity in accounting for income taxes. The amendment is effective for fiscal years beginning after December 15, 2021 and early adoption is permitted. The Company is currently evaluating the impact of this update on its consolidated financial position or results of operation. In March 2020, the FASB issued ASU No. 2020-04— Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting . The amendments of ASU No. 2020-04 are effective for companies as of March 12, 2020 through December 31, 2022. An entity may elect to apply the amendments for contract modifications by Topic or Industry Subtopic as of any date from the beginning of an interim period that includes or is subsequent to March 12, 2020, or prospectively from a date within an interim period that includes or is subsequent to March 12, 2020, up to the date that the financial statements are available to be issued. The amendments in this update apply only to contracts, hedging relationships and other transactions that reference LIBOR or another reference rate expected to be discontinued because of reference rate reform and provide optional expedients and exceptions for applying U.S. GAAP to contracts, hedging relationships and other transactions affected by reference rate reform if certain criteria are met. The Company is evaluating the impact that the amendments of this standard would have on its consolidated financial position or results of operations upon adoption.

Business Combinations (Tables)

Business Combinations (Tables)	9 Months Ended
Business Combinations (Tables)	Sep. 30, 2021
Business Combinations [Abstract]
Summary of Transaction Transferred	On October 27, 2020, the Company completed the purchase of all outstanding shares of Monocl for a total estimated consideration of $ 46.3 million, and up to $ 60 million, summarized as follows: (in thousands) Cash consideration $ 18,307 Equity issuance 25,439 Contingent consideration 2,600 Purchase price $ 46,346
Summary of Allocation of Purchase Price to the Fair Value of Assets Acquired	The purchase accounting for the Monocl acquisition was finalized as of December 31, 2020. The fair values assigned to tangible and identified intangible assets acquired and liabilities assumed were based on management's estimates and assumptions. The final allocation of the acquisition-date fair values of assets and liabilities as of December 31, 2020, was as follows: (in thousands) Preliminary allocation: October 27, Cash $ 2,774 Accounts receivable 788 Prepaid expenses and other current assets 614 Property and equipment 20 Intangible assets 18,900 Accounts payable and accrued expenses ( 2,137 ) Deferred revenue ( 2,884 ) Total assets acquired and liabilities assumed 18,075 Goodwill 28,271 Purchase price $ 46,346 T
Schedule of Business Acquisition, Pro Forma Information	Unaudited Pro Forma Supplementary Data: Nine Months Ended September 30, 2020 (in thousands) Revenue $ 91,750 Net loss ( 43,763 )

Revenue (Tables)

Revenue (Tables)	9 Months Ended
Revenue (Tables)	Sep. 30, 2021
Revenue From Contract With Customer [Abstract]
Schedule of Disaggregation of Revenue	The following table represents a disaggregation of revenue from arrangements with customers for the three and nine months ended September 30, 2021 and 2020, respectively: Three Months Ended September 30, Nine Months Ended September 30, (in thousands) 2021 2020 2021 2020 Platform subscriptions $ 42,780 $ 29,732 $ 118,545 $ 83,814 Professional services 304 341 1,296 845 Total revenue $ 43,084 $ 30,073 $ 119,841 $ 84,659
Summary of Receivables, Deferred Contract Costs and Contract Liabilities from Contract with Customers	The opening and closing balances of the Company’s receivables, deferred contract costs and contract liabilities from contracts with customers are as follows: (in thousands) September 30, December 31, Accounts receivable, net $ 27,886 $ 33,108 Deferred contract costs 5,359 2,947 Long-term deferred contract costs 9,388 5,952 Deferred revenues 70,179 61,200 Deferred Contract Costs A summary of the activity impacting the deferred contract costs for the nine months ended September 30, 2021 and the year ended December 31, 2020 is presented below: (in thousands) September 30, December 31, Balance at beginning of period $ 8,899 $ 2,885 Costs amortized ( 3,195 ) ( 1,670 ) Additional amounts deferred 9,043 7,684 Balance at end of period 14,747 8,899 Classified as: Current 5,359 2,947 Non-current 9,388 5,952 Total deferred contract costs (deferred commissions) $ 14,747 $ 8,899
Summary of Deferred Revenue Balances	A summary of the activity impacting deferred revenue balances during the nine months ended September 30, 2021 and for the year ended December 31, 2020 is presented below: (in thousands) September 30, December 31, Balance at beginning of period $ 61,200 $ 46,125 Revenue recognized ( 119,841 ) ( 118,317 ) Additional amounts deferred 128,820 133,392 Balance at end of period $ 70,179 $ 61,200
Summary of Remaining Performance Obligation	The remaining performance obligations consisted of the following: (in thousands) September 30, December 31, Current $ 128,653 $ 114,284 Non-current 78,900 58,250 Total $ 207,553 $ 172,534

Accounts Receivable (Tables)

Accounts Receivable (Tables)	9 Months Ended
Accounts Receivable (Tables)	Sep. 30, 2021
Receivables [Abstract]
Schedule of Accounts Receivable	Accounts receivable consisted of the following: (in thousands) September 30, December 31, Accounts receivable $ 28,243 $ 33,635 Unbilled receivable 496 329 28,739 33,964 Less: allowance for doubtful accounts ( 853 ) ( 856 ) Accounts receivable, net $ 27,886 $ 33,108

Property and Equipment (Tables)

Property and Equipment (Tables)	9 Months Ended
Property and Equipment (Tables)	Sep. 30, 2021
Property Plant And Equipment [Abstract]
Schedule of Property and Equipment	Property and equipment consisted of the following: (in thousands) September 30, December 31, Computers and software $ 4,455 $ 3,141 Furniture and equipment 1,580 1,109 Leasehold improvements 2,766 1,781 Construction and software development in process — 128 8,801 6,159 Less: accumulated depreciation and amortization ( 4,104 ) ( 2,911 ) Property and equipment, net $ 4,697 $ 3,248

Goodwill and Intangible Assets

Goodwill and Intangible Assets (Tables)	9 Months Ended
Goodwill and Intangible Assets (Tables)	Sep. 30, 2021
Goodwill And Intangible Assets Disclosure [Abstract]
Schedule of Intangible Assets and Goodwill	The carrying amounts of goodwill and intangible assets, as of September 30, 2021 and December 31, 2020, consist of the following: September 30, 2021 (in thousands) Gross Accumulated Net Carrying Finite-lived intangible assets: Customer relationships $ 370,030 $ ( 84,159 ) $ 285,871 Developed technologies 51,100 ( 15,648 ) 35,452 Tradenames 35,500 ( 4,510 ) 30,990 Database 42,656 ( 28,246 ) 14,410 Total finite-lived intangible assets 499,286 ( 132,563 ) 366,723 Goodwill 1,261,444 — 1,261,444 Total goodwill and Intangible assets $ 1,760,730 $ ( 132,563 ) $ 1,628,167 December 31, 2020 (in thousands) Gross Accumulated Net Carrying Finite-lived intangible assets: Customer relationships $ 370,030 $ ( 58,097 ) $ 311,933 Developed technologies 51,100 ( 10,218 ) 40,882 Tradenames 35,500 ( 2,952 ) 32,548 Database 42,656 ( 17,782 ) 24,874 Total finite-lived intangible assets 499,286 ( 89,049 ) 410,237 Goodwill 1,261,444 — 1,261,444 Total goodwill and Intangible assets $ 1,760,730 $ ( 89,049 ) $ 1,671,681

Long-term Debt (Tables)

Long-term Debt (Tables)	9 Months Ended
Long-term Debt (Tables)	Sep. 30, 2021
Long Term Debt [Abstract]
Schedule of Long-term Debt	Long-term debt consisted of the following as of September 30, 2021 and December 31, 2020, respectively: September 30, 2021 (in thousands) Principal Unamortized debt Total debt, 2021 Term Loan $ 275,000 $ ( 2,737 ) $ 272,263 Less: current portion of long-term debt 6,875 Long-term debt $ 265,388 December 31, 2020 (in thousands) Principal Unamortized debt Total debt, 2019 Term Loan $ 444,375 $ ( 10,865 ) $ 433,510 Paid in kind interest on 2019 Term Loan 10,412 — 10,412 2019 Delayed Draw Term Loan 17,955 — 17,955 Total debt $ 472,742 $ ( 10,865 ) $ 461,877 Less: current portion of long-term debt 4,680 Long-term debt $ 457,197

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	9 Months Ended
Fair Value Measurements (Tables)	Sep. 30, 2021
Fair Value Assets And Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Abstract]
Summary of Valuation Techniques and Significant Unobservable Inputs Used in Recurring Level 3 Fair Value Measurements	The valuation techniques and significant unobservable inputs used in recurring Level 3 fair value measurements were as follows as of September 30, 2021 and December 31, 2020: (in thousands) Fair Value Valuation Technique Unobservable Discount Rate Earn-out liabilities $ 6,905 Income Approach (Real Option Method) Discount rate 2.38 %
Schedule of Reconciliation of Earnout Liabilities Measured at Fair Value on a Recurring Basis Unobservable Inputs	The table below presents a reconciliation of earnout liabilities measured at fair value on a recurring basis using significant unobservable inputs (Level 3): (in thousands) September 30, December 31, Balance at beginning of period $ 5,236 $ — Additions — 2,600 Net change in fair value and other adjustments 3,169 2,636 Payments ( 1,500 ) — Balance at end of period $ 6,905 $ 5,236

Accrued Expenses and Other Cu_2

Accrued Expenses and Other Current Liabilities (Tables)	9 Months Ended
Accrued Expenses and Other Current Liabilities (Tables)	Sep. 30, 2021
Accounts Payable And Accrued Liabilities Current [Abstract]
Schedule of Accrued Expenses and Other Current Liabilities	Accrued expenses and other current liabilities consisted of the following: (in thousands) September 30, December 31, Payroll and payroll-related $ 7,246 $ 7,792 Accrued interest 233 5,365 Contingent consideration, current 6,905 1,500 Sales taxes 1,146 649 Deferred rent 112 583 Other 3,654 1,432 Accrued expenses and other current liabilities $ 19,296 $ 17,321

Stockholders' Equity and Memb_2

Stockholders' Equity and Members' Equity (Tables)	9 Months Ended
Stockholders' Equity and Members' Equity (Tables)	Sep. 30, 2021
Members Equity [Abstract]
Schedule of Stock by Class	The table below provides a summary of the number of Class A and Class B units authorized, issued and outstanding as of December 31, 2020, respectively. December 31, Class A units: Authorized, issued and outstanding Class A units 130,245,990 Class B units: Authorized Class B units 8,088,877 Issued Class B units 3,720,063 Outstanding Class B units (Vested Class B units) 474,920

Equity-Based Compensation (Tabl

Equity-Based Compensation (Tables)	9 Months Ended
Equity-Based Compensation (Tables)	Sep. 30, 2021
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Summary of Equity Based Compensation Expense Recognized	A summary of the expense by line item in the consolidated statements of operations for the three and nine months ended September 30, 2021 and 2020, respectively, is provided in the following table. Three Months Ended September 30, Nine Months Ended September 30, (in thousands) 2021 2020 2021 2020 Cost of revenue $ 48 $ 16 $ 79 $ 46 Sales and marketing 326 132 567 380 Product development 187 93 341 267 General and administrative 1,756 217 3,351 637 Total compensation expense $ 2,317 $ 458 $ 4,338 $ 1,330
Schedule Of assumptions used to estimate the fair value of units between service-based and performance-based shares	Significant assumptions used to estimate the fair value of units were as follows, which were the same between service-based and performance-based shares: September 15, 2021 December 31, 2020 Expected option term 0.30 - 0.70 years 5.5 years Risk-free rate of return 0.01 % - 0.06 % 1.73 % Applied volatility 30 % 35 %
IPO [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Schedule of Company’s Unvested Time-Based and Performance-Based Unit Activity	The following table summarizes the Company’s unvested time-based and performance-based unit activity from January 1, 2021 through September 30, 2021. Time-Based Performance-Based Weighted Weighted Non-Vested Average Grant Non-Vested Average Grant Units Date Fair Value Units Date Fair Value Non-vested at December 31, 2020 1,404,720 $ 3.65 1,840,423 $ 2.35 Granted 1,477,323 1.41 1,177,308 0.41 Vested ( 437,731 ) 3.64 — — Forfeited ( 13,770 ) 3.65 ( 18,361 ) 2.35 Non-vested at September 15, 2021 2,430,542 $ 2.29 2,999,370 $ 1.59 Effect of Reorganization Transactions and IPO ( 1,165,679 ) 2.08 ( 1,318,171 ) 1.39 Performance-based units exchanged for time-based units 1,681,199 1.74 ( 1,681,199 ) 1.74 Vested ( 74,049 ) 2.75 — — Forfeited ( 72,149 ) 2.78 — — Non-vested at September 30, 2021 2,799,864 $ 2.02 — $ —
Restricted Stock [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Schedule of Company’s Unvested Time-Based and Performance-Based Unit Activity	The following table summarizes the Company’s unvested time-based and performance-based RSU activity for the nine months ended September 30, 2021. Time-Based Performance-Based Weighted Weighted Restricted Average Grant Restricted Average Grant Stock Units Date Fair Value Stock Units Date Fair Value Unvested at beginning of period — $ - — $ - Granted 1,300,328 $ 27.00 164,353 $ 27.00 Vested — $ - — $ - Forfeited ( 2,656 ) $ 27.00 — $ - Unvested at end of period 1,297,672 $ 27.00 164,353 $ 27.00

Loss Per Share (Tables)

Loss Per Share (Tables)	9 Months Ended
Loss Per Share (Tables)	Sep. 30, 2021
Earnings Per Share [Abstract]
Schedule of Net Loss Per Share, Basic and Diluted	The following table sets forth reconciliations of the numerators and denominators used to compute basic and diluted net loss per share of Class A Common Stock for the three- and nine-months ended September 30, 2021. (in thousands) Three Months Nine Months Numerator: Net loss $ ( 20,966 ) $ ( 46,493 ) Less: Net loss attributable to Definitive OpCo before Reorganization Transactions ( 7,816 ) ( 33,343 ) Less: Net loss attributable to noncontrolling interests ( 5,172 ) ( 5,172 ) Net loss attributable to Definitive Healthcare Corp. $ ( 7,978 ) $ ( 7,978 ) The following table sets forth the computation of basic and diluted net loss per share of Class A Common Stock (per share amounts unaudited): (in thousands, except number of shares and per share amounts) Three Months Nine Months Basic net loss per share attributable to common stockholders Numerator: Allocation of net loss attributable to Definitive Healthcare Corp. $ ( 7,978 ) $ ( 7,978 ) Weighted average number of shares of Class A outstanding 88,263,333 88,263,333 Net loss per share, basic and diluted $ ( 0.09 ) $ ( 0.09 )
Schedule of Dilutive Securities Excluded from Computation of Diluted Net Loss Per Share	The following table presents potentially dilutive securities excluded from the computation of diluted net loss per share for the period presented because their effect would have been anti-dilutive: Nine Months Definitive OpCo Units 57,192,893

Segment and Geographic Data (Ta

Segment and Geographic Data (Tables)	9 Months Ended
Segment and Geographic Data (Tables)	Sep. 30, 2021
Segment Reporting [Abstract]
Schedule of Revenue by Geographic Areas	Revenues by geographic area presented based upon the location of the customer are as follows: For the Three Months Ended September 30, For the Nine Months Ended September 30, (in thousands) 2021 2020 2021 2020 United States $ 40,863 $ 30,073 $ 114,339 $ 84,659 Rest of world 2,221 — 5,502 — Total revenues $ 43,084 $ 30,073 $ 119,841 $ 84,659
Schedule of Long-Lived Assets by Geographic Areas	Long-lived assets by geographical region are based on the location of the legal entity that owns the assets. Long-lived assets by geographic area presented based upon the location of the assets are as follows: (in thousands) September 30, December 31, United States $ 4,311 $ 3,120 Rest of world 386 128 Total long-lived assets $ 4,697 $ 3,248

Description of Business - Addit

Description of Business - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions	Sep. 17, 2021	Sep. 30, 2021
Entity Incorporation, Date of Incorporation		May 5, 2021
Proceeds from Issuance Initial Public Offering	$ 199.6
Acquisition of Limited Liability Company (LLC)	14,222,222
Purchase Of Limited Liability Company (LLC) Unit	1,169,378
Common Class A [Member]
Stock Issued During Period Shares New Issues	17,888,888
Share Price	$ 27
Proceeds from Issuance Initial Public Offering	$ 452.8
Stock Repurchased During Period, Shares	2,497,288

Business Combinations - Additio

Business Combinations - Additional Information (Details) - USD ($) $ in Thousands	Oct. 27, 2020	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2021	Dec. 31, 2019
Purchase price				$ 46,346
Cash consideration				18,307
Equity issuance				25,439
Contingent consideration				2,600
Fair value of the contingent consideration		$ 6,900		6,900		$ 5,200
Deferred revenue		70,179		70,179		61,200		$ 46,125
Business combination, Contingent consideration, Liability		6,900		6,900		5,200
Business combination, Acquisition related costs	$ 400
Revenue		43,084	$ 30,073	119,841	$ 84,659
Net loss		(7,978)		(7,978)
Interest expense		$ 400	$ 500	$ 1,500	1,500
Trademarks [Member]
Business combination, Recognized identifiable assets acquired and liabilities assumed, Other noncurrent assets	$ 1,400
Estimated useful life	19 years
Customer Relationships [Member]
Business combination, Recognized identifiable assets acquired and liabilities assumed, Other noncurrent assets	$ 11,900
Estimated useful life	14 years
Data [Member]
Business combination, Recognized identifiable assets acquired and liabilities assumed, Other noncurrent assets	$ 3,000
Estimated useful life	3 years
Technology [Member]
Business combination, Recognized identifiable assets acquired and liabilities assumed, Other noncurrent assets	$ 2,600
Estimated useful life	8 years
Goodwill [Member]
Business combination, Recognized identifiable assets acquired and liabilities assumed, Other noncurrent assets	$ 28,300
Series of Individually Immaterial Business Acquisitions [Member]
Potential payouts range, Low						0
Potential payouts range, High						5,000
Series of Individually Immaterial Business Acquisitions [Member] \| Forecast [Member]
Potential payouts range, Low							$ 0
Potential payouts range, High							10,000
Monocl Holding Company [Member]
Revenue						1,200
Net loss						1,600
Adjustments to amortization expense					600
Interest expense					$ 800
Minimum [Member] \| Series of Individually Immaterial Business Acquisitions [Member]
Annual recurring revenue						8,500
Minimum [Member] \| Series of Individually Immaterial Business Acquisitions [Member] \| Forecast [Member]
Annual recurring revenue							12,000
Minimum [Member] \| Monocl Holding Company [Member]
Purchase price	46,300
Maximum [Member] \| Series of Individually Immaterial Business Acquisitions [Member]
Annual recurring revenue						$ 9,500
Maximum [Member] \| Series of Individually Immaterial Business Acquisitions [Member] \| Forecast [Member]
Annual recurring revenue							$ 16,000
Maximum [Member] \| Monocl Holding Company [Member]
Purchase price	$ 60,000

Business Combinations - Summary

Business Combinations - Summary of Transaction Transferred (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2021USD ($)
Business Combinations [Abstract]
Cash consideration	$ 18,307
Equity issuance	25,439
Contingent consideration	2,600
Purchase price	$ 46,346

Business Combinations - Summa_2

Business Combinations - Summary of Allocation of Purchase Price to the Fair Value of Assets Acquired (Details) $ in Thousands	Oct. 27, 2020USD ($)
Business Combinations [Abstract]
Cash	$ 2,774
Accounts receivable	788
Prepaid expenses and other current assets	614
Property and equipment	20
Intangible assets	18,900
Accounts payable and accrued expenses	(2,137)
Deferred revenue	(2,884)
Total assets acquired and liabilities assumed	18,075
Goodwill	28,271
Purchase price	$ 46,346

Business Combinations - Schedul

Business Combinations - Schedule of Business Acquisition, Pro Forma Information (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2020USD ($)
Business Combinations [Abstract]
Revenue	$ 91,750
Net loss	$ (43,763)

Revenue - Schedule of Disaggreg

Revenue - Schedule of Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Disaggregation Of Revenue [Line Items]
Revenue	$ 43,084	$ 30,073	$ 119,841	$ 84,659
Platform Subscriptions [Member]
Disaggregation Of Revenue [Line Items]
Revenue	42,780	29,732	118,545	83,814
Professional Services [Member]
Disaggregation Of Revenue [Line Items]
Revenue	$ 304	$ 341	$ 1,296	$ 845

Revenue - Summary of Receivable

Revenue - Summary of Receivables, Deferred Contract Costs and Contract Liabilities from Contract with Customers (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Revenue From Contract With Customer [Abstract]
Accounts receivable, net	$ 27,886	$ 33,108
Current portion of deferred contract costs	5,359	2,947
Long-term deferred contract costs	9,388	5,952
Deferred revenues	$ 70,179	$ 61,200

Revenue - Summary of Deferred C

Revenue - Summary of Deferred Contract Costs (Details) - USD ($) $ in Thousands	9 Months Ended		12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Revenue Initial Application Period Cumulative Effect Transition [Line Items]
Additional amounts deferred	$ 128,820		$ 133,392
Deferred contract costs, net of current portion	9,388		5,952
Deferred contract costs	(9,043)	$ (4,341)
Deferred Contract Costs [Member]
Revenue Initial Application Period Cumulative Effect Transition [Line Items]
Balance at beginning of period	8,899	$ 2,885	2,885
Costs amortized	(3,195)		(1,670)
Additional amounts deferred	9,043		7,684
Balance at end of period	14,747		8,899
Deferred contract costs, net of current portion	5,359		2,947
Non-current	9,388		5,952
Deferred contract costs	$ 14,747		$ 8,899

Revenue - Summary of Deferred R

Revenue - Summary of Deferred Revenue Balances (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2021	Dec. 31, 2020
Revenue From Contract With Customer [Abstract]
Balance at beginning of period	$ 61,200	$ 46,125
Revenue recognized	(119,841)	(118,317)
Additional amounts deferred	128,820	133,392
Balance at end of period	$ 70,179	$ 61,200

Revenue - Summary of Remaining

Revenue - Summary of Remaining Performance Obligation (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Revenue From Contract With Customer [Abstract]
Current	$ 128,653	$ 114,284
Noncurrent	78,900	58,250
Total	$ 207,553	$ 172,534

Accounts Receivable - Schedule

Accounts Receivable - Schedule of Accounts Receivable (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Accounts Notes And Loans Receivable Net Current [Abstract]
Accounts receivable	$ 28,243	$ 33,635
Unbilled receivable	496	329
Accounts receivable, gross	28,739	33,964
Less: allowance for doubtful accounts	(853)	(856)
Accounts receivable, net	$ 27,886	$ 33,108

Property and Equipment - Schedu

Property and Equipment - Schedule of Property and Equipment (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Property Plant And Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 8,801	$ 6,159
Less: accumulated depreciation and amortization	(4,104)	(2,911)
Property and equipment, net	4,697	3,248
Computers and Software [Member]
Property Plant And Equipment [Line Items]
Property, Plant and Equipment, Gross	4,455	3,141
Furniture and Equipment [Member]
Property Plant And Equipment [Line Items]
Property, Plant and Equipment, Gross	1,580	1,109
Leasehold Improvements [Member]
Property Plant And Equipment [Line Items]
Property, Plant and Equipment, Gross	2,766	1,781
Construction and Software Development in Process [Member]
Property Plant And Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 0	$ 128

Property and Equipment - Additi

Property and Equipment - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Property Plant And Equipment [Line Items]
Depreciation and amortization	$ 9,760	$ 10,112	$ 28,814	$ 30,037
Property And Equipment [Member]
Property Plant And Equipment [Line Items]
Depreciation and amortization	$ 500	$ 300	$ 1,200	$ 800

Goodwill and Intangible Asset_2

Goodwill and Intangible Assets - Schedule of Intangible Assets and Goodwill (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 499,286	$ 499,286
Accumulated Amortization	(132,563)	(89,049)
Net Carrying Amount	366,723	410,237
Goodwill [Member]
Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	1,261,444	1,261,444
Accumulated Amortization	0	0
Net Carrying Amount	1,261,444	1,261,444
Goodwill And Intangible Assets [Member]
Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	1,760,730	1,760,730
Accumulated Amortization	(132,563)	(89,049)
Net Carrying Amount	1,628,167	1,671,681
Customer Relationships [Member]
Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	370,030	370,030
Accumulated Amortization	(84,159)	(58,097)
Net Carrying Amount	285,871	311,933
Developed Technology [Member]
Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	51,100	51,100
Accumulated Amortization	(15,648)	(10,218)
Net Carrying Amount	35,452	40,882
Trade Names [Member]
Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	35,500	35,500
Accumulated Amortization	(4,510)	(2,952)
Net Carrying Amount	30,990	32,548
Databases [Member]
Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	42,656	42,656
Accumulated Amortization	(28,246)	(17,782)
Net Carrying Amount	$ 14,410	$ 24,874

Goodwill and Intangible Asset_3

Goodwill and Intangible Assets - Additional Information (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021USD ($)	Sep. 30, 2020USD ($)	Sep. 30, 2021USD ($)Segment	Sep. 30, 2020USD ($)
Finite Lived Intangible Assets [Line Items]
Amortization of intangible assets			$ 43,517	$ 43,498
Amortization	$ 5,356	$ 4,794	$ 15,896	14,278
Number of Reporting Units \| Segment			1
Impairment of goodwill			$ 0	0
Finite Lived Intangible Assets [Member]
Finite Lived Intangible Assets [Line Items]
Amortization of intangible assets	14,700	14,600	43,500	43,500
Amortization	$ 5,400	$ 4,800	$ 15,900	$ 14,300

Long-term Debt - Schedule of Lo

Long-term Debt - Schedule of Long-term Debt (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Sep. 17, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Principal		$ 474,600	$ 472,742
Unamortized debt issuance costs / financing costs		(9,900)	(10,865)
Total debt, net			461,877
Less: current portion of long-term debt	$ 6,875		4,680
Long-term debt	265,388		457,197
2021 Term Loan [Member]
Debt Instrument [Line Items]
Principal	275,000	275,000
Unamortized debt issuance costs / financing costs	(2,737)
Total debt, net	$ 272,263
2019 Term Loan [Member]
Debt Instrument [Line Items]
Principal		442,100	444,375
Unamortized debt issuance costs / financing costs			(10,865)
Total debt, net			433,510
Paid in Kind Interest on 2019 Term Loan [Member]
Debt Instrument [Line Items]
Principal		10,400	10,412
Total debt, net			10,412
2019 Delayed Draw Term Loan [Member]
Debt Instrument [Line Items]
Principal		$ 17,900	17,955
Total debt, net			$ 17,955

Long-term Debt - Additional Inf

Long-term Debt - Additional Information (Details) - USD ($) $ in Thousands	Sep. 17, 2021	Jul. 16, 2021	Dec. 31, 2020	Oct. 31, 2020	Dec. 31, 2019	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Jul. 16, 2019
Debt Instrument [Line Items]
Outstanding principal balance	$ 474,600		$ 472,742							$ 472,742
Proceeds from issuance of IPO	$ 199,600
Interest expense						$ 400	$ 500	$ 1,500	$ 1,500
Frequency of payment								The 2021 Term Loan is subject to annual amortization of principal, payable in equal quarterly installments on the last day of each fiscal quarter, commencing on December 31, 2021 (the "Initial Amortization Date"), equal to approximately 2.5% per annum of the principal amount of the term loans in the first year and second year after the Initial Amortization Date and approximately 5.0% per annum of the principal amount of the term loans in the third year, fourth year and fifth year after the Initial Amortization Date.
Noncash paid in kind interest expense									7,371
Proceeds from revolving credit facility									25,000
Interest rate	6.25%
Financing costs				$ 14,100				$ 3,500
Interest expense						400	$ 500	1,500	$ 1,500
Unamortized debt issuance costs / financing costs	$ 9,900		10,865							10,865
2019 Term Loan [Member]
Debt Instrument [Line Items]
Outstanding principal balance	442,100		444,375							444,375
Interest payable	4,200
Face amount of loan						450,000		$ 450,000
Maturity date								Jul. 16, 2026
Original issue discount								$ 11,300
Interest expense								100,000
Line of credit			$ 454,800							454,800	$ 450,000
Quarterly principal payment					$ 1,100
Balloon payment					$ 419,600
Noncash paid in kind interest expense										$ 10,400
Interest rate			6.50%							6.50%
Financing costs				13,400
Interest expense								100,000
Unamortized debt issuance costs / financing costs			$ 10,865							$ 10,865
2021 Term Loan [Member]
Debt Instrument [Line Items]
Outstanding principal balance	$ 275,000					275,000		275,000
Maturity date	Sep. 17, 2026
Balloon payment						$ 220,000		$ 220,000
Interest rate						2.37%		2.37%
Financing costs								$ 2,800
Unamortized debt issuance costs / financing costs						$ 2,737		$ 2,737
Paid in Kind Interest on 2019 Term Loan [Member]
Debt Instrument [Line Items]
Outstanding principal balance	$ 10,400		10,412							10,412
2019 Delayed Draw Term Loan [Member]
Debt Instrument [Line Items]
Outstanding principal balance	$ 17,900		17,955							17,955
Maturity date								Jul. 16, 2026
Original issue discount								$ 1,300
Line of credit			$ 18,000							18,000	100,000
Proceeds from revolving credit facility										$ 18,000
Percentage of installment amount			0.25%
Percentage of amount paid to bank		1.00%
Interest rate			6.50%							6.50%
Financing costs				200
2021 Revolving Line of Credit [Member]
Debt Instrument [Line Items]
Maturity date	Sep. 17, 2026
Line of credit	$ 75,000					$ 0		$ 0
Interest rate						2.37%		2.37%
Financing costs								$ 800
2021 Revolving Line of Credit [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Unused commitment fee percentage								0.25%
2021 Revolving Line of Credit [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Unused commitment fee percentage								0.30%
2019 Revolving Line of Credit [Member]
Debt Instrument [Line Items]
Maturity date								Jul. 16, 2024
Line of credit			$ 0							$ 0	$ 25,000
Line of credit, expiration period								Sep. 17, 2021
Proceeds from revolving credit facility								$ 0		25,000
Repayments of Lines of Credit										25,000
Financing costs				$ 700
Unamortized debt issuance costs / financing costs			$ 500							$ 500

Fair Value Measurements - Addit

Fair Value Measurements - Additional Information (Details) - USD ($) $ in Millions	Sep. 30, 2021	Apr. 30, 2021	Dec. 31, 2020
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Business combination, Contingent consideration, Liability	$ 6.9		$ 5.2
Earnout liability current	6.9		1.5
Business combination contingent consideration liability other	0		$ 3.7
Earn out payments		$ 1.5
Maximum [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Potential earn out payments	10
Minimum [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Potential earn out payments	$ 0

Fair Value - Summary of Valuati

Fair Value - Summary of Valuation Techniques and Significant Unobservable Inputs Used in Recurring Level 3 Fair Value Measurements (Details) - Fair Value, Nonrecurring - Fair Value, Inputs, Level 3 - Earn Out Liabilities - Income Approach (Real Option Method) - Discount rate - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2021	Dec. 31, 2020
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Fair Value	$ 6,905	$ 6,905
Discount Rate	2.38%	2.38%

Fair Value - Schedule of Reconc

Fair Value - Schedule of Reconciliation of Earnout Liabilities Measured at Fair Value on a Recurring Basis Unobservable Inputs (Details) - Fair Value, Inputs, Level 3 - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2021	Dec. 31, 2020
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Balance at beginning of period	$ 5,236	$ 0
Additions	0	2,600
Net change in fair value and other adjustments	3,169	2,636
Payments	(1,500)	0
Balance at end of period	$ 6,905	$ 5,236

Accrued Expenses and Other Cu_3

Accrued Expenses and Other Current Liabilities - Schedule of Accrued Expenses And Other Current Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Accounts Payable And Accrued Liabilities Current [Abstract]
Payroll and payroll-related	$ 7,246	$ 7,792
Accrued interest	233	5,365
Contingent consideration, current	6,905	1,500
Sales taxes	1,146	649
Deferred rent	112	583
Other	3,654	1,432
Accrued expenses and other current liabilities	$ 19,296	$ 17,321

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Commitments And Contingencies Disclosure [Abstract]
Total rent expense	$ 0.7	$ 0.5	$ 2.1	$ 1.4

Stockholders' Equity and Memb_3

Stockholders' Equity and Members' Equity - Summary of Class of Stock (Details) - shares	Sep. 30, 2021	Dec. 31, 2020
Class A Units
Class Of Stock [Line Items]
Authorized, issued and outstanding Class A units		130,245,990
Issued Class B units	363,516
Class B Units
Class Of Stock [Line Items]
Authorized Class B units		8,088,877
Issued Class B units		3,720,063
Outstanding Class B units (Vested Class B units)		474,920

Stockholders' Equity and Memb_4

Stockholders' Equity and Members' Equity - Additional Information (Details) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2021USD ($)shares	Sep. 30, 2021USD ($)shares
Class Of Stock [Line Items]
Capital units, value	$ 5,800	$ 5,800
Members' contributions		5,500
Equity-based compensation	$ 2,595	$ 300
Preferred stock, shares issued \| shares	0	0
Class A Units
Class Of Stock [Line Items]
Class A units issued \| shares	363,516	363,516

Equity-Based Compensation - Add

Equity-Based Compensation - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands	Sep. 17, 2021	Jul. 31, 2019	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Sep. 15, 2021
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Members' contributions					$ 5,500
Stock-based compensation expense			$ 2,317	$ 458	4,338	$ 1,330
Equity-based compensation			2,595		300
Time Based Unit
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized expense related to unit-based compensation			18,400		$ 18,400
Weighted-average period over which cost not yet recognized is expected to be recognized					2 years 9 months 18 days
General And Administrative Expense
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense			1,756	$ 217	$ 3,351	$ 637
Class B Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share based compensation vested number of shares					912,651
Share based compensation vested number of shares participation threshold after modification					578,217
2019 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share based compensation cost	$ 9,000
Share based compensation number of shares available for grant							0
2019 Equity Incentive Plan \| Performance-Based
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense			200
2019 Equity Incentive Plan \| Class B Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares reserved for issuance		8,088,877
2021 Equity Incentive Plan \| Restricted Stock Unit
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense					$ 400
2021 Equity Incentive Plan \| Performance-Based
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense			0
Unrecognized expense related to unit-based compensation			39,100		$ 39,100
Weighted-average period over which cost not yet recognized is expected to be recognized					4 years
2021 Equity Incentive Plan \| Time Based Unit
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized expense related to unit-based compensation			$ 39,100		$ 39,100
Weighted-average period over which cost not yet recognized is expected to be recognized					4 years
2021 Equity Incentive Plan \| Restricted Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized			1,464,681		1,464,681
2021 Equity Incentive Plan \| Class A Common Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized			8,989,039		8,989,039
IPO \| 2019 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period	3 years
Issue price per share	$ 27
Executive Officer
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share based compensation plan modification incremental compensation cost			$ 1,900
Executive Officer \| Class B Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share based compensation number of shares forfeitured in period		72,149
Executive Officer \| Class B Units \| Performance-Based
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share based compensation accelerated vesting number of shares		48,099
Executive Officer \| 2019 Equity Incentive Plan \| Class B Units \| Time Based Unit
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share based compensation accelerated vesting number of shares		24,049

Equity-Based Compensation - Sum

Equity-Based Compensation - Summary of Activity Relating to Time Based and Performance Based Stock Options (Details) - $ / shares	1 Months Ended	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2021	Sep. 15, 2021
Time-Based RSUs
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Non-vested at December 31, 2020		0	0
Granted		1,300,328
Vested		0
Forfeited		(2,656)
Non-vested at September 30, 2021	1,297,672	1,297,672
Non vested weighted average grant date fair value		$ 0	$ 0
Non vested weighted average grant date fair value, Granted		27
Non vested weighted average grant date fair value, vested		0
Non vested weighted average grant date fair value, forfeited		27
Non vested weighted average grant date fair value	$ 27	$ 27
Performance-Based RSUs
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Non-vested at December 31, 2020		0	0
Granted		164,353
Vested		0
Forfeited		0
Non-vested at September 30, 2021	164,353	164,353
Non vested weighted average grant date fair value		$ 0	$ 0
Non vested weighted average grant date fair value, Granted		27
Non vested weighted average grant date fair value, vested		0
Non vested weighted average grant date fair value, forfeited		0
Non vested weighted average grant date fair value	$ 27	$ 27
Time Based Unit
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Non-vested at December 31, 2020	2,430,542	1,404,720	1,404,720
Effect of Reorganization Transactions and IPO	(1,165,679)
Performance-based units exchanged for time-based units	1,681,199
Granted			1,477,323
Vested	(74,049)		(437,731)
Forfeited	(72,149)		(13,770)
Non-vested at September 30, 2021	2,799,864	2,799,864	2,430,542
Non vested weighted average grant date fair value	$ 2.29	$ 3.65	$ 3.65
Non vested weighted average effect of reorganization transactions and IPO fair value	2.08
Weighted average grant date fair value performance-based units exchanged for time-based units	1.74
Non vested weighted average grant date fair value, Granted			1.41
Non vested weighted average grant date fair value, vested	2.75		3.64
Non vested weighted average grant date fair value, forfeited	2.78		3.65
Non vested weighted average grant date fair value	$ 2.02	$ 2.02	$ 2.29
Performance-Based
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Non-vested at December 31, 2020	2,999,370	1,840,423	1,840,423
Effect of Reorganization Transactions and IPO	(1,318,171)
Performance-based units exchanged for time-based units	(1,681,199)
Granted			1,177,308
Vested
Forfeited			(18,361)
Non-vested at September 30, 2021			2,999,370
Non vested weighted average grant date fair value	$ 1.59	$ 2.35	$ 2.35
Non vested weighted average effect of reorganization transactions and IPO fair value	1.39
Weighted average grant date fair value performance-based units exchanged for time-based units	1.74
Non vested weighted average grant date fair value, Granted			0.41
Non vested weighted average grant date fair value, vested	0		0
Non vested weighted average grant date fair value, forfeited	0		2.35
Non vested weighted average grant date fair value	$ 0	$ 0	$ 1.59

Equity-Based Compensation - Sch

Equity-Based Compensation - Schedule Of assumptions used to estimate the fair value of units between service-based and performance-based shares (Details)	9 Months Ended	12 Months Ended
	Sep. 30, 2021	Dec. 31, 2020
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected option term		5 years 6 months
Risk-free rate of return		1.73%
Applied volatility	30.00%	35.00%
Minimum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected option term	3 months 18 days
Risk-free rate of return	0.01%
Maximum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected option term	8 months 12 days
Risk-free rate of return	0.06%

Equity-Based Compensation Expen

Equity-Based Compensation Expense - Summary of Equity Based Compensation Expense Recognized (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 2,317	$ 458	$ 4,338	$ 1,330
Cost of revenue
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	48	16	79	46
Sales and marketing
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	326	132	567	380
Product development
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	187	93	341	267
General and administrative
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 1,756	$ 217	$ 3,351	$ 637

Retirement Plans - Additional I

Retirement Plans - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Compensation And Retirement Disclosure [Abstract]
Employer matching contributions, amount	$ 0.6	$ 0.4	$ 1.7	$ 1.1

Income Taxes - Additional Infor

Income Taxes - Additional Information (Details) - USD ($)	3 Months Ended		9 Months Ended
Income Taxes - Additional Information (Details) - USD ($)	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Unrecognized tax benefits	$ 0		$ 0		$ 0
Effective tax rate	(0.30%)	0.00%	(0.30%)	0.00%
Deferred tax liability	$ 71,300,000		$ 71,300,000
Tax receivable agreement liability			$ 146,100,000
Tax receivable agreement realized tax benefits payable to related parties percent			85.00%
Tax Receivable Agreement Benefit percentage			15.00%
Tax Receivable Agreement Realized Tax Benefits Payable To Related Parties			$ 0

Loss Per Share - Calculation of

Loss Per Share - Calculation of Net Loss Per Share, Basic and Diluted (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Net loss		$ (20,966)	$ (9,962)	$ (46,493)	$ (35,295)
Less: Net loss attributable to Definitive OpCo prior to the Reorganization Transactions		(7,816)	$ (9,962)	(33,343)	$ (35,295)
Less: Net loss attributable to noncontrolling interests		(5,172)		(5,172)
Net loss attributable to Definitive Healthcare Corp.		(7,978)		(7,978)
Basic net loss per share attributable to common stockholders [Abstract]
Allocation of net loss attributable to Definitive Healthcare Corp.		$ (7,978)		$ (7,978)
Net loss per share, basic and diluted		$ (0.09)		$ (0.09)
Weighted average number of shares of Class A outstanding	[1]	88,263,333		88,263,333
Common Class A [Member]
Net loss		$ (20,966)		$ (46,493)
Less: Net loss attributable to Definitive OpCo prior to the Reorganization Transactions		(7,816)		(33,343)
Less: Net loss attributable to noncontrolling interests		(5,172)		(5,172)
Net loss attributable to Definitive Healthcare Corp.		(7,978)		(7,978)
Basic net loss per share attributable to common stockholders [Abstract]
Allocation of net loss attributable to Definitive Healthcare Corp.		$ (7,978)		$ (7,978)
Net loss per share, basic and diluted		$ (0.09)		$ (0.09)
Weighted average number of shares of Class A outstanding		88,263,333		88,263,333

[1]	Basic and diluted net loss per share of Class A Common Stock is applicable only for the period from September 15, 2021 through September 30, 2021, which is the period following the initial public offering ("IPO") and related Reorganization Transactions (as defined in Note 1 to the Unaudited Consolidated Financial Statements). See Note 16 for the number of shares used in the computation of net loss per share of Class A Common Stock and the basis for the computation of net loss per share.

Loss Per Share - Dilutive Secur

Loss Per Share - Dilutive Securities Excluded from Computation of Diluted Net loss Per Share (Details)	9 Months Ended
	Sep. 30, 2021shares
Definitive OpCo Units	57,192,893

Segment and Geographic Data - S

Segment and Geographic Data - Schedule of Revenue by Geographic Areas (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Entity Wide Revenue Major Customer [Line Items]
Revenue	$ 43,084	$ 30,073	$ 119,841	$ 84,659
United States [Member]
Entity Wide Revenue Major Customer [Line Items]
Revenue	40,863	30,073	114,339	84,659
Rest of World [Member]
Entity Wide Revenue Major Customer [Line Items]
Revenue	$ 2,221	$ 0	$ 5,502	$ 0

Segment and Geographic Data -_2

Segment and Geographic Data - Schedule of Long-Lived Assets by Geographic Areas) (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Revenues From External Customers And Long Lived Assets [Line Items]
Total long-lived assets	$ 4,697	$ 3,248
United States [Member]
Revenues From External Customers And Long Lived Assets [Line Items]
Total long-lived assets	4,311	3,120
Rest of World [Member]
Revenues From External Customers And Long Lived Assets [Line Items]
Total long-lived assets	$ 386	$ 128

Related parties - Additional In

Related parties - Additional Information (Details) - USD ($) $ in Millions	Sep. 17, 2021	Jun. 30, 2021	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Related Party Transaction [Line Items]
Revenue from related parties			$ 0.7	$ 0.6
Receivable, related parties			0.1		$ 0.7
Related party transaction, expenses from transactions with related party			0.2	$ 0
Payable, related parties, current			$ 0		$ 0
Sale of Stock, Description of Transaction		Richard Booth and Samuel A. Hamood participated in the Directed Share Program and purchased 7,407 and 37,037 shares of Class A Common Stock, respectively.
Common Class A [Member]
Related Party Transaction [Line Items]
Stock issued during period, shares, new issues	17,888,888
Common Class A [Member] \| Richard Booth [Member] \| Directed Share Program [Member]
Related Party Transaction [Line Items]
Share purchased		7,407,000
Common Class A [Member] \| Samuel A. Hamood [Member] \| Directed Share Program [Member]
Related Party Transaction [Line Items]
Share purchased		37,037,000
Definitive OpCo [Member]
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party	$ 0.9
Definitive Healthcare Corp. [Member]
Related Party Transaction [Line Items]
Common Stock Capital Shares Underwriters Reserved For Sale At IPO		5.00%
Class A Units
Related Party Transaction [Line Items]
Stock issued during period, shares, new issues		363,516
Stock issued during period, value, new issues		$ 5.8

Noncontrolling Interest - Addit

Noncontrolling Interest - Additional Information (Details) - Definitive OpCo [Member]	Sep. 30, 2021shares
Noncontrolling Interest [Line Items]
Number of shares held	88,263,333
Ownership interest (as a percent)	60.70%

Subsequent Events - Additional

Subsequent Events - Additional Information (Details) - Subsequent Event [Member] - USD ($) $ in Millions	Oct. 08, 2021	Oct. 07, 2021
Common Class A [Member] \| Restricted Stock Units (RSUs) [Member]
Subsequent Event [Line Items]
Share based compensation number of shares available for grant	216,450	433,550
Shares vesting percentage	33.00%	25.00%
Quarterly vesting rights percentage	8.33%	6.25%
President [Member]
Subsequent Event [Line Items]
Annual base salary		$ 0.4
Percentage of annual bonus		68.00%