Disaggregation of revenue

9 Months Ended

Sep. 30, 2025

Revenue from Contract with Customer [Abstract]

Disaggregation of revenue

Revenue disaggregated by customer concentration is as follows:


	Three Months Ended March 31,
	2025 (As Restated)		2024 (As Restated)		2023 (As Restated)
	(in thousands)

Clients 1-5	$	496,118	$	539,035	$	567,913
Clients 6-10	309,562		313,756		269,815
Clients 11-25	475,299		422,459		413,296
Other	734,341		768,004		714,784
Total	$	2,015,320	$	2,043,254	$	1,965,808


	Three Months Ended June 30,						Six Months Ended June 30,
	2025 (As Restated)		2024 (As Restated)		2023 (As Restated)		2025 (As Restated)		2024 (As Restated)		2023 (As Restated)
	(in thousands)

Clients 1-5	$	502,385	$	509,632	$	528,152	$	998,504	$	1,048,666	$	1,088,264
Clients 6-10	300,080		301,723		282,313		607,546		607,270		559,930
Clients 11-25	523,737		436,571		415,996		994,379		865,334		822,819
Other	712,886		794,000		781,740		1,453,979		1,563,910		1,502,996
Total	$	2,039,088	$	2,041,926	$	2,008,201	$	4,054,408	$	4,085,180	$	3,974,009


	Three Months Ended September 30,						Nine Months Ended September 30,
	2025 (As Restated)		2024 (As Restated)		2023 (As Restated)		2025 (As Restated)		2024 (As Restated)		2023 (As Restated)
	(in thousands)

Clients 1-5	$	501,343	$	508,385	$	515,190	$	1,499,847	$	1,547,372	$	1,602,943
Clients 6-10	308,045		324,708		294,715		890,203		939,831		855,156
Clients 11-25	541,879		454,808		460,192		1,546,626		1,316,277		1,272,595
Other	733,148		754,042		770,217		2,202,147		2,323,643		2,283,629
Total	$	2,084,415	$	2,041,943	$	2,040,314	$	6,138,823	$	6,127,123	$	6,014,323

There was no revenue from individual customers greater than 10% of consolidated revenue in the respective years. Our customers have similar profiles and economic characteristics, and therefore have similar degrees of risk and growth opportunities.

Accounts receivable, unbilled revenue (contract assets) and unearned revenue or payments on account (contract liabilities)

Accounts receivable and unbilled revenue were as follows for the periods ended:


	March 31, 2025 (As Restated)		June 30, 2025 (As Restated)		September 30, 2025 (As Restated)
	(in thousands)
Accounts receivable (Billed services)	$	1,426,035	$	1,411,329	$	1,427,376
Allowance for credit losses	(38,573)		(44,074)		(39,686)
Accounts receivable (net)	1,387,462		1,367,255		1,387,690
Unbilled revenue (Unbilled services)	1,101,511		1,173,021		1,195,747
Accounts receivable and unbilled revenue, net	$	2,488,973	$	2,540,276	$	2,583,437


	March 31, 2024 (As Restated)		June 30, 2024 (As Restated)		September 30, 2024 (As Restated)
	(in thousands)
Accounts receivable (Billed services)	$	1,737,822	$	1,608,774	$	1,431,581
Allowance for credit losses	(35,303)		(40,122)		(35,501)
Accounts receivable (net)	1,702,519		1,568,652		1,396,080
Unbilled revenue (Unbilled services)	949,567		1,021,519		1,118,860
Accounts receivable and unbilled revenue, net	$	2,652,086	$	2,590,171	$	2,514,940


	March 31, 2023 (As Restated)		June 30, 2023 (As Restated)		September 30, 2023 (As Restated)
	(in thousands)
Accounts receivable (Billed services)	$	1,838,875	$	1,788,140	$	1,883,296
Allowance for credit losses	(36,149)		(29,029)		(32,934)
Accounts receivable (net)	1,802,726		1,759,111		1,850,362
Unbilled revenue (Unbilled services)	880,412		902,321		828,453
Accounts receivable and unbilled revenue, net	$	2,683,138	$	2,661,432	$	2,678,815

Unbilled services and unearned revenue or payments on account (contract assets and liabilities) were as follows for the periods ended:


	March 31, 2025 (As Restated)		June 30, 2025 (As Restated)		September 30, 2025 (As Restated)
	(in thousands)
Unbilled revenue (Unbilled services)	$	1,101,511	$	1,173,021	$	1,195,747
Unearned revenue (Payments on account )	(1,495,847)		(1,515,422)		(1,546,887)


	March 31, 2024 (As Restated)		June 30, 2024 (As Restated)		September 30, 2024 (As Restated)
	(in thousands)
Unbilled revenue (Unbilled services)	$	949,567	$	1,021,519	$	1,118,860
Unearned revenue (Payments on account )	(1,585,694)		(1,544,275)		(1,477,952)


	March 31, 2023 (As Restated)		June 30, 2023 (As Restated)		September 30, 2023 (As Restated)
	(in thousands)
Unbilled revenue (Unbilled services)	$	880,412	$	902,321	$	828,453
Unearned revenue (Payments on account )	(1,480,275)		(1,493,403)		(1,563,948)

Timing may differ between the satisfaction of performance obligations and the invoicing and collection of amounts related to our contracts with customers. We record assets for amounts related to performance obligations that are satisfied but not yet billed and/or collected. These assets are recorded as unbilled revenue and therefore contract assets rather than accounts receivable when receipt of the consideration is conditional on something other than the passage of time. Liabilities are recorded for amounts that are collected in advance of the satisfaction of performance obligations or billed in advance of the revenue being earned.

Unbilled services / revenue balances arise where invoicing or billing is based on the timing of agreed milestones related to service contracts for clinical research. Contractual billing arrangements in respect of certain reimbursable expenses (principally investigators) require billing by the investigator to the Company prior to billing by the Company to the customer. As there is no contractual right of set-off between unbilled services (contract assets) and unearned revenue (contract liabilities), each are separately presented gross on the Consolidated Balance Sheets.

- Definition

The entire disclosure of revenue from contract with customer to transfer good or service and to transfer nonfinancial asset. Includes, but is not limited to, disaggregation of revenue, credit loss recognized from contract with customer, judgment and change in judgment related to contract with customer, and asset recognized from cost incurred to obtain or fulfill contract with customer. Excludes insurance and lease contracts.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-7

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-9

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-10

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 15
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-15

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-12

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-12

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-12

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-12

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-12

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-13

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
-Topic 606
-Publisher FASB
-URI https://asc.fasb.org/606/tableOfContent

+ Details

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