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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
FORM 6-K/A
Report of Foreign Private Issuer
Pursuant to Rule 13a-16 or 15d-16 under
the Securities Exchange Act of 1934
For the month of
May 2026
333-08704
(Commission file number)
ICON plc
(Translation of registrant's name into English)
South County Business Park, Leopardstown, Dublin 18, D18 X5R3, Ireland
(Address of principal executive offices)

Indicate by check mark whether the registrant files or will file annual reports under cover of Form 20-F or Form 40-F.
| Form 20-F___X___ | Form 40-F______

ICON plc
This report on Form 6-K/A is hereby incorporated by reference into the registration statements of ICON plc on Form S-8 (Registration Nos. 333-152802, 333-204153, 333-231527, 333-254891, 333-257578 and 333-282826) and on Form F-3 (Registration No. 333-278943), and this report on Form 6-K/A shall be deemed a part of each such registration statement from the date on which this report is filed, to the extent not superseded by documents or reports subsequently filed or furnished by ICON plc under the Securities Act of 1933 or the Securities Exchange Act of 1934.

EXPLANATORY NOTE
Overview
As described in our Report on Form 6-K furnished on April 29, 2026, the Audit Committee of the Board of Directors (the “Audit Committee”), after discussion with management of the Company, concluded on April 27, 2026, that the Company’s previously issued audited financial statements included in its Annual Reports on Form 20-F for the years ended December 31, 2024 and 2023 (the “Affected Audited Periods”) and the unaudited interim financial statements included in the Company’s Current Reports on Form 6-K for the quarterly periods ending on and falling between September 30, 2025 and March 31, 2023 (the “Affected Unaudited Periods” and together with the Affected Audited Periods, the “Restated Periods”) should no longer be relied upon. We refer to the the Company’s Current Reports on Form 6-K with respect to the Affected Unaudited Periods as the "Affected Form 6-K Reports."
We are filing this Amendment No. 1 on Form 6-K (this "Amendment" or "Form 6-K/A") to amend the Report on Form 6-K originally filed by the Company with the Securities and Exchange Commission (the "SEC") on October 23, 2025 to restate the Company's previously issued unaudited condensed consolidated financial statements for the Affected Unaudited Periods that were included in the Affected Form 6-K Reports. This Amendment also amends certain other information impacted by the Restatement (as defined below) that was included in the Affected Form 6-K Reports. All material restatement information for the Affected Unaudited Periods is included in this Amendment, and the Company does not intend to separately amend other reports it has previously filed with the SEC.
In this Form 6-K/A, we are including the following:
•the restated unaudited condensed consolidated Balance Sheets as of March 31, June 30, and September 30, of each of 2023, 2024, and 2025; and
•the restated unaudited condensed consolidated Statements of Operations and, Statements of Comprehensive Income for each of the three months and year to date periods ended March 31, June 30, and September 30, of each of 2023, 2024, and 2025; and
•the restated unaudited condensed consolidated Statements of Shareholders' Equity for each of the three months ended March 31, June 30, and September 30, of each of 2023, 2024, and 2025; and
•the restated unaudited condensed consolidated Statements of Cash Flows for each of the year to date periods ended March 31, June 30, and September 30, of each of 2023, 2024, and 2025.
We refer to the foregoing restatements in this document as the “Restatement.”
Restatement Background
As previously disclosed, in October 2025, the Audit Committee initiated an investigation into certain accounting practices and controls, following concerns reported to the Audit Committee through Company management. The Audit Committee promptly engaged outside legal counsel, who were supported by forensic and technical accounting firms, to conduct the investigation (the “Investigation”) and notified the Company’s independent registered public accounting firm. The Company has also self-reported the matter to the SEC and other relevant agencies. The Investigation primarily focused on revenue recognition practices, and, in connection with the Investigation, the Company has determined that improper adjustments were made to the clinical trial services revenue of the Company from the third quarter of 2023 to the fourth quarter of 2024. The Company also identified errors in determining the estimated cost to complete, the assessment of realizable value, and certain manual adjustments in respect of clinical trial services revenue contracts during 2023, 2024 and 2025. The Audit Committee concluded that the Company’s previously issued consolidated financial statements for the Restated Periods should no longer be relied upon and that such financial statements required restatement.
The Company has restated the audited financial statements for the Affected Audited Periods in the Annual Report on Form 20-F for the year ended December 31, 2025 (our "Form 20-F") and is filing this Amendment to restate the unaudited interim financial statements for the Affected Unaudited Periods.
Restatement of Financial Statements for the Affected Unaudited Periods
In addition to the errors outlined in our Form 20-F, the following errors were identified that impacted the Affected Unaudited Periods.
•In preparing the Company's goodwill impairment assessment as at December 31, 2025, the Company identified additional goodwill impairment and concluded that it should have been recorded as at September 30, 2025 and has included this within the restated September 30, 2025 unaudited condensed consolidated financial statements.
•Errors were identified between unbilled revenue and accounts receivable, net of allowance for credit losses as at March 31, and June 30, 2024. An overstatement of $160.0 million and $1.0 million were identified in accounts receivable, net of allowance for credit losses with a corresponding understatement of unbilled revenue as at March 31, and June 30, 2024 respectively.
1

Effect of Restatement
The effect of this restatement on the Company's unaudited condensed consolidated Statements of Operations for each of the Affected Unaudited Periods is as follows (only impacted lines are presented):

| March 31, 2025 |  | June 30, 2025 |  | September 30, 2025
| Three Months Ended |  | Three Months Ended |  | Three Months Ended
| As Reported | Adjustments | As Restated |  | As Reported | Adjustments | As Restated |  | As Reported | Adjustments | As Restated
| (in thousands)
Revenue | $ | 2,001,332 |  | $ | 13,988 |  | $ | 2,015,320 |  |  | $ | 2,017,357 |  | $ | 21,731 |  | $ | 2,039,088 |  |  | $ | 2,042,812 |  | $ | 41,603 |  | $ | 2,084,415 |
Direct costs | 1,442,679 |  | 6,579 |  | 1,449,258 |  |  | 1,455,758 |  | — |  | 1,455,758 |  |  | 1,488,364 |  | 50,587 |  | 1,538,951 |
Depreciation and amortization | 95,958 |  | — |  | 95,958 |  |  | 97,718 |  | — |  | 97,718 |  |  | 98,495 |  | 535 |  | 99,030 |
Goodwill impairment | — |  | — |  | — |  |  | — |  | — |  | — |  |  | 165,300 |  | 198,948 |  | 364,248 |
Impairment of non-financial assets | — |  | — |  | — |  |  | — |  | — |  | — |  |  | — |  | 101,027 |  | 101,027 |
Total costs and expenses | 1,781,771 |  | 6,579 |  | 1,788,350 |  |  | 1,808,149 |  | — |  | 1,808,149 |  |  | 1,956,228 |  | 351,097 |  | 2,307,325 |
Income / (loss) from operations | 219,561 |  | 7,409 |  | 226,970 |  |  | 209,208 |  | 21,731 |  | 230,939 |  |  | 86,584 |  | (309,494) |  | (222,910) |
Income tax (expense) / benefit | (19,603) |  | (748) |  | (20,351) |  |  | 21,861 |  | (1,187) |  | 20,674 |  |  | (35,747) |  | 22,956 |  | (12,791) |
Net income / (loss) | $ | 154,151 |  | $ | 6,661 |  | $ | 160,812 |  |  | $ | 182,972 |  | $ | 20,544 |  | $ | 203,516 |  |  | $ | 2,355 |  | $ | (286,538) |  | $ | (284,183) |

| March 31, 2024 |  | June 30, 2024 |  | September 30, 2024
| Three Months Ended |  | Three Months Ended |  | Three Months Ended
| As Reported | Adjustments | As Restated |  | As Reported | Adjustments | As Restated |  | As Reported | Adjustments | As Restated
| (in thousands)
Revenue | $ | 2,090,386 |  | $ | (47,132) |  | $ | 2,043,254 |  |  | $ | 2,120,159 |  | $ | (78,233) |  | $ | 2,041,926 |  |  | $ | 2,030,030 |  | $ | 11,913 |  | $ | 2,041,943 |
Direct costs | 1,471,367 |  | (4,083) |  | 1,467,284 |  |  | 1,493,600 |  | (5,344) |  | 1,488,256 |  |  | 1,438,616 |  | (5,222) |  | 1,433,394 |
Total costs and expenses | 1,804,889 |  | (4,083) |  | 1,800,806 |  |  | 1,890,302 |  | (5,344) |  | 1,884,958 |  |  | 1,744,596 |  | (5,222) |  | 1,739,374 |
Income from operations | 285,497 |  | (43,049) |  | 242,448 |  |  | 229,857 |  | (72,889) |  | 156,968 |  |  | 285,434 |  | 17,135 |  | 302,569 |
Income tax expense | (28,324) |  | 3,948 |  | (24,376) |  |  | (23,344) |  | 8,755 |  | (14,589) |  |  | (37,437) |  | (995) |  | (38,432) |
Net income | $ | 187,438 |  | $ | (39,101) |  | $ | 148,337 |  |  | $ | 146,910 |  | $ | (64,134) |  | $ | 82,776 |  |  | $ | 197,128 |  | $ | 16,140 |  | $ | 213,268 |

2

| March 31, 2023 |  | June 30, 2023 |  | September 30, 2023
| Three Months Ended |  | Three Months Ended |  | Three Months Ended
| As Reported | Adjustments | As Restated |  | As Reported | Adjustments | As Restated |  | As Reported | Adjustments | As Restated
| (in thousands)
Revenue | $ | 1,978,578 |  | $ | (12,770) |  | $ | 1,965,808 |  |  | $ | 2,020,251 |  | $ | (12,050) |  | $ | 2,008,201 |  |  | $ | 2,055,099 |  | $ | (14,785) |  | $ | 2,040,314 |
Direct costs | 1,395,546 |  | (3,624) |  | 1,391,922 |  |  | 1,429,540 |  | (3,134) |  | 1,426,406 |  |  | 1,449,136 |  | (3,394) |  | 1,445,742 |
Total costs and expenses | 1,761,789 |  | (3,624) |  | 1,758,165 |  |  | 1,810,767 |  | (3,134) |  | 1,807,633 |  |  | 1,790,788 |  | (3,394) |  | 1,787,394 |
Income from operations | 216,789 |  | (9,146) |  | 207,643 |  |  | 209,484 |  | (8,916) |  | 200,568 |  |  | 264,311 |  | (11,391) |  | 252,920 |
Income tax expense | (14,273) |  | 1,369 |  | (12,904) |  |  | (9,629) |  | 1,363 |  | (8,266) |  |  | (18,011) |  | 1,627 |  | (16,384) |
Net income | $ | 116,654 |  | $ | (7,777) |  | $ | 108,877 |  |  | $ | 115,598 |  | $ | (7,553) |  | $ | 108,045 |  |  | $ | 163,665 |  | $ | (9,764) |  | $ | 153,901 |

3

GENERAL
As used herein, “ICON plc”, “ICON”, "ICON Group", the “Company” and “we”, "our" or “us” refer to ICON public limited company and its consolidated subsidiaries, unless the context requires otherwise.
Unless otherwise indicated, ICON plc’s financial statements and other financial data contained in this Form 6-K/A are presented in United States dollars (“$”) and are prepared in accordance with generally accepted accounting principles in the United States (“U.S. GAAP”).
In this Form 6-K/A, references to “U.S. dollars”, “U.S.$” or “$” are to the lawful currency of the United States, references to “euro” or “€” are to the European single currency adopted by certain members of the European Union, references to “pound sterling”, “sterling”, “£”, “pence” or “p” are to the lawful currency of the United Kingdom. ICON publishes its consolidated financial statements in U.S. dollars.
Cautionary Statement Regarding Forward-looking Statements
Statements included herein which are not historical facts are forward-looking statements. Such forward-looking statements are made pursuant to the safe harbor provisions of the U.S. Private Securities Litigation Reform Act of 1995. Examples of forward-looking statements include, but are not limited to, statements regarding the following: the remediation of material weaknesses in the Company's internal control over financial reporting and the implementation of the Company's corrective action plan; the Company's expectations regarding business momentum, market opportunity, demand trends, growth, and commercial performance; and the Company's expectations with respect to its long-term value creation and competitive positioning. You can identify many forward-looking statements by words such as “aims,” “anticipates,” “believes,” “continues,” “could,” “estimates,” “expects,” “focused,” “guidance,” “intends,” “look,” “may,” “opportunities,” “plans,” “positions,” “potential,” “predicts,” “projects,” “seeks,” “should,” “will,” “would” and other similar expressions and the negatives of such expressions. However, not all forward-looking statements contain these words. These statements are based on management's current expectations and information currently available, including current economic and industry conditions. The forward looking statements involve a number of risks and uncertainties and are subject to change at any time. In the event such risks or uncertainties materialize, our results could be materially adversely affected. The risks and uncertainties include, but are not limited to, dependence on the pharmaceutical industry and certain clients, the need to regularly win projects and then to execute them efficiently and correctly, the challenges presented by rapid growth, competition and the continuing consolidation of the industry, the impact of market conditions on demand for the Company's services, risks related to the Company's ability to execute on its commercial strategy and maintain relationships with large pharmaceutical customers, risks relating to the Company's strategic partnerships, the dependence on certain key executives, changes in the regulatory environment, exchange rate fluctuations, inflation and rising labor costs, the effect of material weaknesses on our internal control over financial reporting, and the risk that material weaknesses in the Company's internal control over financial reporting are not remediated on the timeline expected or at all. Please also refer to the section entitled "Risk Factors" of our Form 20-F filed on May 27, 2026 for a discussion of some of the principal risks that could adversely affect our business, operations and financial results. The Company’s forward-looking statements speak only as of the date of this report or as of the date they are made, and the Company undertakes no obligation to update its forward-looking statements.
Restatement of Unaudited Condensed Consolidated Financial Statements
Restatement of Previously Issued Quarterly Financial Statements
The Company is presenting herein restated unaudited condensed consolidated financial information for the fiscal quarters and year-to-date periods ended March 31, June 30 and September 30, 2025; March 31, June 30 and September 30, 2024; and March 31, June 30 and September 30, 2023.
4

The table below sets forth the unaudited condensed Consolidated Statements of Operations, including the balances originally reported in the Company’s unaudited condensed Consolidated financial statements, the effects of the adjustments made and the restated balances for each of the three months and year to date periods ended March 31, June 30, and September 30 of 2025.
ICON plc
CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (UNAUDITED)

| March 31, 2025 |  | June 30, 2025
| Three Months Ended |  | Three Months Ended |  | Six Months Ended
| As Reported | Adjustments | As Restated |  | As Reported | Adjustments | As Restated |  | As Reported | Adjustments | As Restated
| (in thousands, except share and per share data)
Revenue | $ | 2,001,332 |  | $ | 13,988 |  | $ | 2,015,320 |  |  | $ | 2,017,357 |  | $ | 21,731 |  | $ | 2,039,088 |  |  | $ | 4,018,689 |  | $ | 35,719 |  | $ | 4,054,408 |
Costs and expenses: |  |  |  |  |  |  |  |  |  |  |
Direct costs | 1,442,679 |  | 6,579 |  | 1,449,258 |  |  | 1,455,758 |  | — |  | 1,455,758 |  |  | 2,898,437 |  | 6,579 |  | 2,905,016 |
Selling, general and administrative | 198,384 |  | — |  | 198,384 |  |  | 205,006 |  | — |  | 205,006 |  |  | 403,390 |  | — |  | 403,390 |
Depreciation and amortization | 95,958 |  | — |  | 95,958 |  |  | 97,718 |  | — |  | 97,718 |  |  | 193,676 |  | — |  | 193,676 |
Transaction and integration related | 5,404 |  | — |  | 5,404 |  |  | 6,717 |  | — |  | 6,717 |  |  | 12,121 |  | — |  | 12,121 |
Restructuring | 39,346 |  | — |  | 39,346 |  |  | 42,950 |  | — |  | 42,950 |  |  | 82,296 |  | — |  | 82,296 |
Total costs and expenses | 1,781,771 |  | 6,579 |  | 1,788,350 |  |  | 1,808,149 |  | — |  | 1,808,149 |  |  | 3,589,920 |  | 6,579 |  | 3,596,499 |
Income from operations | 219,561 |  | 7,409 |  | 226,970 |  |  | 209,208 |  | 21,731 |  | 230,939 |  |  | 428,769 |  | 29,140 |  | 457,909 |
Interest income | 1,802 |  | — |  | 1,802 |  |  | 2,054 |  | — |  | 2,054 |  |  | 3,856 |  | — |  | 3,856 |
Interest expense | (47,609) |  | — |  | (47,609) |  |  | (50,151) |  | — |  | (50,151) |  |  | (97,760) |  | — |  | (97,760) |
Income before income tax (expense) / benefit | 173,754 |  | 7,409 |  | 181,163 |  |  | 161,111 |  | 21,731 |  | 182,842 |  |  | 334,865 |  | 29,140 |  | 364,005 |
Income tax (expense) / benefit | (19,603) |  | (748) |  | (20,351) |  |  | 21,861 |  | (1,187) |  | 20,674 |  |  | 2,258 |  | (1,935) |  | 323 |
Net income | $ | 154,151 |  | $ | 6,661 |  | $ | 160,812 |  |  | $ | 182,972 |  | $ | 20,544 |  | $ | 203,516 |  |  | $ | 337,123 |  | $ | 27,205 |  | $ | 364,328 |
Net income per ordinary share: |  |  |  |  |  |  |  |  |  |  |
Basic | $ | 1.91 |  |  | $ | 2.00 |  |  | $ | 2.31 |  |  | $ | 2.57 |  |  | $ | 4.22 |  |  | $ | 4.56 |
Diluted | $ | 1.90 |  |  | $ | 1.99 |  |  | $ | 2.30 |  |  | $ | 2.56 |  |  | $ | 4.20 |  |  | $ | 4.54 |
Weighted average number of ordinary shares outstanding: |  |  |  |  |  |  |  |  |  |
Basic | 80,552,734 |  |  | 80,552,734 |  |  | 79,245,448 |  |  | 79,245,448 |  |  | 79,899,091 |  |  | 79,899,091 |
Diluted | 80,924,355 |  |  | 80,924,355 |  |  | 79,547,444 |  |  | 79,547,444 |  |  | 80,235,900 |  |  | 80,235,900 |

5

ICON plc
CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (UNAUDITED)

| September 30, 2025 |  |  |  |  |  |
| Three Months Ended |  | Nine Months Ended |  |  |  |  |  |
| As Reported | Adjustments | As Restated |  | As Reported | Adjustments | As Restated |  |  |  |  |  |  |  |
| (in thousands, except share and per share data) |  |  |  |
Revenue | $ | 2,042,812 |  | $ | 41,603 |  | $ | 2,084,415 |  |  | $ | 6,061,501 |  | $ | 77,322 |  | $ | 6,138,823 |  |  |  |  |  |  |  |  |
Costs and expenses: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Direct costs | 1,488,364 |  | 50,587 |  | 1,538,951 |  |  | 4,386,801 |  | 57,166 |  | 4,443,967 |  |  |  |  |  |  |  |  |
Selling, general and administrative | 197,049 |  | — |  | 197,049 |  |  | 600,439 |  | — |  | 600,439 |  |  |  |  |  |  |  |  |
Depreciation and amortization | 98,495 |  | 535 |  | 99,030 |  |  | 292,171 |  | 535 |  | 292,706 |  |  |  |  |  |  |  |  |
Transaction and integration related | 7,020 |  | — |  | 7,020 |  |  | 19,141 |  | — |  | 19,141 |  |  |  |  |  |  |  |  |
Restructuring | — |  | — |  | — |  |  | 82,296 |  | — |  | 82,296 |  |  |  |  |  |  |  |  |
Goodwill impairment | 165,300 |  | 198,948 |  | 364,248 |  |  | 165,300 |  | 198,948 |  | 364,248 |  |  |  |  |  |  |  |  |
Impairment of non-financial assets | — |  | 101,027 |  | 101,027 |  |  | — |  | 101,027 |  | 101,027 |  |  |  |  |  |  |  |  |
Total costs and expenses | 1,956,228 |  | 351,097 |  | 2,307,325 |  |  | 5,546,148 |  | 357,676 |  | 5,903,824 |  |  |  |  |  |  |  |  |
(Loss) / income from operations | 86,584 |  | (309,494) |  | (222,910) |  |  | 515,353 |  | (280,354) |  | 234,999 |  |  |  |  |  |  |  |  |
Interest income | 1,761 |  | — |  | 1,761 |  |  | 5,617 |  | — |  | 5,617 |  |  |  |  |  |  |  |  |
Interest expense | (50,243) |  | — |  | (50,243) |  |  | (148,003) |  | — |  | (148,003) |  |  |  |  |  |  |  |  |
(Loss) / income before income tax expense | 38,102 |  | (309,494) |  | (271,392) |  |  | 372,967 |  | (280,354) |  | 92,613 |  |  |  |  |  |  |  |  |
Income tax expense | (35,747) |  | 22,956 |  | (12,791) |  |  | (33,489) |  | 21,021 |  | (12,468) |  |  |  |  |  |  |  |  |
Net (loss) / income | $ | 2,355 |  | $ | (286,538) |  | $ | (284,183) |  |  | $ | 339,478 |  | $ | (259,333) |  | $ | 80,145 |  |  |  |  |  |  |  |  |
Net (loss) / income per ordinary share: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Basic | $ | 0.03 |  |  | $ | (3.67) |  |  | $ | 4.29 |  |  | $ | 1.01 |  |  |  |  |  |  |  |  |
Diluted | $ | 0.03 |  |  | $ | (3.67) |  |  | $ | 4.27 |  |  | $ | 1.01 |  |  |  |  |  |  |  |  |
Weighted average number of ordinary shares outstanding: |  |  |  |  |  |  |  |  |  |  |  |  |  |
Basic | 77,373,534 |  |  | 77,373,534 |  |  | 79,057,239 |  |  | 79,057,239 |  |  |  |  |  |  |  |  |
Diluted | 78,082,459 |  |  | 77,373,534 |  |  | 79,518,086 |  |  | 79,518,086 |  |  |  |  |  |  |  |  |

6

The table below sets forth the unaudited condensed Consolidated Statements of Comprehensive Income, including the balances originally reported in the Company’s unaudited condensed Consolidated financial statements, the effects of the adjustments made and the restated balances for each of the three months and year to date periods ended March 31, June 30, and September 30 of 2025.

ICON plc
CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED)
| March 31, 2025 |  | June 30, 2025
| Three Months Ended |  | Three Months Ended |  | Six Months Ended
| As Reported | Adjustments | As Restated |  | As Reported | Adjustments | As Restated |  | As Reported | Adjustments | As Restated
| (in thousands)
Net income | $ | 154,151 |  | $ | 6,661 |  | $ | 160,812 |  |  | $ | 182,972 |  | $ | 20,544 |  | $ | 203,516 |  |  | $ | 337,123 |  | $ | 27,205 |  | $ | 364,328 |
Other comprehensive income, net of tax: |  |  |  |  |  |  |  |  |  |  |
Currency translation adjustment | 59,158 |  | — |  | 59,158 |  |  | 104,428 |  | — |  | 104,428 |  |  | 163,586 |  | — |  | 163,586 |
Movement on cash flow hedge | (2,420) |  | — |  | (2,420) |  |  | — |  | — |  | — |  |  | (2,420) |  | — |  | (2,420) |
Total comprehensive income | $ | 210,889 |  | $ | 6,661 |  | $ | 217,550 |  |  | $ | 287,400 |  | $ | 20,544 |  | $ | 307,944 |  |  | $ | 498,289 |  | $ | 27,205 |  | $ | 525,494 |

ICON plc
CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED)
| September 30, 2025 |  |
| Three Months Ended |  | Nine Months Ended |  |
| As Reported | Adjustments | As Restated |  | As Reported | Adjustments | As Restated |  |  |  |
| (in thousands)
Net (loss) / income | $ | 2,355 |  | $ | (286,538) |  | $ | (284,183) |  |  | $ | 339,478 |  | $ | (259,333) |  | $ | 80,145 |  |  |  |  |
Other comprehensive (loss) / income, net of tax: |  |  |  |  |  |  |  |  |  |  |
Currency translation adjustment | (18,181) |  | — |  | (18,181) |  |  | 145,405 |  | — |  | 145,405 |  |  |  |  |
Movement on cash flow hedge | — |  | — |  | — |  |  | (2,420) |  | — |  | (2,420) |  |  |  |  |
Total comprehensive (loss) / income | $ | (15,826) |  | $ | (286,538) |  | $ | (302,364) |  |  | $ | 482,463 |  | $ | (259,333) |  | $ | 223,130 |  |  |  |  |

7

The table below sets forth unaudited condensed Consolidated Balance Sheets, including the balances originally reported in the Company’s unaudited condensed Consolidated financial statements, the effects of the adjustments made and the restated balances as at March 31, June 30, and September 30 of 2025.
ICON plc
CONDENSED CONSOLIDATED BALANCE SHEETS (UNAUDITED)

| March 31, 2025 |  | June 30, 2025 |  | September 30, 2025
| As Reported | Adjustments | As Restated |  | As Reported | Adjustments | As Restated |  | As Reported | Adjustments | As Restated
| (in thousands)
ASSETS |  |  |  |  |  |  |  |  |  |  |
Current assets: |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents | $ | 526,698 |  | $ | — |  | $ | 526,698 |  |  | $ | 390,396 |  | $ | — |  | $ | 390,396 |  |  | $ | 468,888 |  | $ | — |  | $ | 468,888 |
Accounts receivable, net of allowance for credit losses | 1,387,462 |  | — |  | 1,387,462 |  |  | 1,367,255 |  | — |  | 1,367,255 |  |  | 1,387,690 |  | — |  | 1,387,690 |
Unbilled revenue | 1,197,080 |  | (95,569) |  | 1,101,511 |  |  | 1,244,560 |  | (71,539) |  | 1,173,021 |  |  | 1,258,706 |  | (62,959) |  | 1,195,747 |
Other receivables | 87,490 |  | — |  | 87,490 |  |  | 80,637 |  | — |  | 80,637 |  |  | 91,018 |  | — |  | 91,018 |
Prepayments and other current assets | 153,340 |  | — |  | 153,340 |  |  | 143,263 |  | — |  | 143,263 |  |  | 140,713 |  | (1,925) |  | 138,788 |
Income taxes receivable | 63,969 |  | — |  | 63,969 |  |  | 83,292 |  | — |  | 83,292 |  |  | 61,626 |  | — |  | 61,626 |
Total current assets | $ | 3,416,039 |  | $ | (95,569) |  | $ | 3,320,470 |  |  | $ | 3,309,403 |  | $ | (71,539) |  | $ | 3,237,864 |  |  | $ | 3,408,641 |  | $ | (64,884) |  | $ | 3,343,757 |
Non-current assets: |  |  |  |  |  |  |  |  |  |  |
Property, plant and equipment, net | 378,253 |  | — |  | 378,253 |  |  | 377,979 |  | — |  | 377,979 |  |  | 390,837 |  | (12,898) |  | 377,939 |
Goodwill | 9,065,335 |  | — |  | 9,065,335 |  |  | 9,092,410 |  | — |  | 9,092,410 |  |  | 8,927,323 |  | (198,948) |  | 8,728,375 |
Intangible assets, net | 3,501,307 |  | — |  | 3,501,307 |  |  | 3,443,096 |  | — |  | 3,443,096 |  |  | 3,384,322 |  | (86,739) |  | 3,297,583 |
Operating right-of-use assets | 147,377 |  | — |  | 147,377 |  |  | 140,352 |  | — |  | 140,352 |  |  | 134,341 |  | — |  | 134,341 |
Other receivables | 75,122 |  | — |  | 75,122 |  |  | 85,032 |  | — |  | 85,032 |  |  | 89,932 |  | — |  | 89,932 |
Income taxes receivable | — |  | 11,395 |  | 11,395 |  |  | — |  | 11,395 |  | 11,395 |  |  | — |  | 11,395 |  | 11,395 |
Deferred tax asset | 77,404 |  | 2,456 |  | 79,860 |  |  | 86,275 |  | 2,456 |  | 88,731 |  |  | 100,810 |  | 2,456 |  | 103,266 |
Investments in equity | 62,160 |  | — |  | 62,160 |  |  | 67,743 |  | — |  | 67,743 |  |  | 71,284 |  | — |  | 71,284 |
Total Assets | $ | 16,722,997 |  | $ | (81,718) |  | $ | 16,641,279 |  |  | $ | 16,602,290 |  | $ | (57,688) |  | $ | 16,544,602 |  |  | $ | 16,507,490 |  | $ | (349,618) |  | $ | 16,157,872 |
LIABILITIES AND SHAREHOLDERS’ EQUITY |  |  |  |  |  |  |  |  |  |  |
Current liabilities: |  |  |  |  |  |  |  |  |  |  |
Accounts payable | 118,168 |  | — |  | 118,168 |  |  | 94,503 |  | — |  | 94,503 |  |  | 113,288 |  | — |  | 113,288 |
Unearned revenue | 1,497,166 |  | (1,319) |  | 1,495,847 |  |  | 1,514,442 |  | 980 |  | 1,515,422 |  |  | 1,528,343 |  | 18,544 |  | 1,546,887 |
Other liabilities | 994,308 |  | (7,248) |  | 987,060 |  |  | 898,909 |  | (7,248) |  | 891,661 |  |  | 998,472 |  | (7,248) |  | 991,224 |
Income taxes payable | 49,888 |  | 748 |  | 50,636 |  |  | 19,347 |  | 1,935 |  | 21,282 |  |  | 49,350 |  | 1,448 |  | 50,798 |
Current bank credit lines, loan facilities and notes | 29,762 |  | — |  | 29,762 |  |  | 29,762 |  | — |  | 29,762 |  |  | 529,762 |  | — |  | 529,762 |
Total current liabilities | $ | 2,689,292 |  | $ | (7,819) |  | $ | 2,681,473 |  |  | $ | 2,556,963 |  | $ | (4,333) |  | $ | 2,552,630 |  |  | $ | 3,219,215 |  | $ | 12,744 |  | $ | 3,231,959 |

8

ICON plc
CONDENSED CONSOLIDATED BALANCE SHEETS (UNAUDITED)

| March 31, 2025 |  | June 30, 2025 |  | September 30, 2025
| As Reported | Adjustments | As Restated |  | As Reported | Adjustments | As Restated |  | As Reported | Adjustments | As Restated
| (in thousands)
Non-current liabilities: |  |  |  |  |  |  |  |  |  |  |
Non-current bank credit lines, loan facilities and notes, net | 3,390,438 |  | — |  | 3,390,438 |  |  | 3,384,488 |  | — |  | 3,384,488 |  |  | 2,878,547 |  | — |  | 2,878,547 |
Lease liabilities | 138,354 |  | — |  | 138,354 |  |  | 132,713 |  | — |  | 132,713 |  |  | 125,110 |  | — |  | 125,110 |
Non-current other liabilities | 85,713 |  | (752) |  | 84,961 |  |  | 97,057 |  | (752) |  | 96,305 |  |  | 99,490 |  | (752) |  | 98,738 |
Non-current income taxes payable | 129,529 |  | 1,710 |  | 131,239 |  |  | 100,916 |  | 1,710 |  | 102,626 |  |  | 105,832 |  | 1,710 |  | 107,542 |
Deferred tax liability | 788,816 |  | 127 |  | 788,943 |  |  | 775,066 |  | 127 |  | 775,193 |  |  | 744,450 |  | (22,342) |  | 722,108 |
Commitments and contingencies | — |  | — |  | — |  |  | — |  | — |  | — |  |  | — |  | — |  | — |
Total Liabilities | $ | 7,222,142 |  | $ | (6,734) |  | $ | 7,215,408 |  |  | $ | 7,047,203 |  | $ | (3,248) |  | $ | 7,043,955 |  |  | $ | 7,172,644 |  | $ | (8,640) |  | $ | 7,164,004 |
Shareholders' Equity: |  |  |  |  |  |  |  |  |  |  |
Ordinary shares par value 6 euro cents per share; 100,000,000 shares authorized |  |  |  |  |  |  |  |  |  |  |
79,464,252 shares issued and outstanding at March 31, 2025 (June 30, 2025: 77,772,130 and September 30, 2025: 76,359,932) | 6,505 |  | — |  | 6,505 |  |  | 6,390 |  | — |  | 6,390 |  |  | 6,290 |  | — |  | 6,290 |
Additional paid-in capital | 7,037,344 |  | — |  | 7,037,344 |  |  | 7,054,324 |  | — |  | 7,054,324 |  |  | 7,100,059 |  | — |  | 7,100,059 |
Other undenominated capital | 1,389 |  | — |  | 1,389 |  |  | 1,506 |  | — |  | 1,506 |  |  | 1,606 |  | — |  | 1,606 |
Accumulated other comprehensive loss | (173,191) |  | — |  | (173,191) |  |  | (68,763) |  | — |  | (68,763) |  |  | (86,944) |  | — |  | (86,944) |
Retained earnings | 2,628,808 |  | (74,984) |  | 2,553,824 |  |  | 2,561,630 |  | (54,440) |  | 2,507,190 |  |  | 2,313,835 |  | (340,978) |  | 1,972,857 |
Total Shareholders' Equity | $ | 9,500,855 |  | $ | (74,984) |  | $ | 9,425,871 |  |  | $ | 9,555,087 |  | $ | (54,440) |  | $ | 9,500,647 |  |  | $ | 9,334,846 |  | $ | (340,978) |  | $ | 8,993,868 |
Total Liabilities and Shareholders’ Equity | $ | 16,722,997 |  | $ | (81,718) |  | $ | 16,641,279 |  |  | $ | 16,602,290 |  | $ | (57,688) |  | $ | 16,544,602 |  |  | $ | 16,507,490 |  | $ | (349,618) |  | $ | 16,157,872 |

9

The following table presents summarized restated unaudited condensed Consolidated Statements of Shareholders’ Equity for three months ended March 31, June 30, and September 30 of 2025.

ICON plc
CONDENSED CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY (UNAUDITED)
| Number of Ordinary Shares | Ordinary Shares | Additional Paid-in Capital | Other Undenominated Capital | Accumulated Other Comprehensive Loss | Retained Earnings (As Restated) | Total
| ( in thousands, except share data)
Balance at December 31, 2024 (as restated) | 80,756,860 |  | $ | 6,586 |  | $ | 7,020,231 |  | $ | 1,304 |  | $ | (229,929) |  | $ | 2,643,162 |  | $ | 9,441,354 |
Comprehensive income (net of tax): |  |  |  |  |  |  |
Net income (as restated) | — |  | — |  | — |  | — |  | — |  | 160,812 |  | 160,812 |
Currency translation adjustment | — |  | — |  | — |  | — |  | 59,158 |  | — |  | 59,158 |
Movement on cash flow hedge | — |  | — |  | — |  | — |  | (2,420) |  | — |  | (2,420) |
Total Comprehensive Income (as restated) |  |  |  |  |  |  | 217,550 |
Exercise of share options | 40,883 |  | 3 |  | 4,759 |  | — |  | — |  | — |  | 4,762 |
Issue of restricted share units / performance share units | 27,046 |  | 1 |  | — |  | — |  | — |  | — |  | 1 |
Share based compensation expense | — |  | — |  | 12,359 |  | — |  | — |  | — |  | 12,359 |
Share issuance costs | — |  | — |  | (5) |  | — |  | — |  | — |  | (5) |
Repurchase of ordinary shares | (1,360,537) |  | (85) |  | — |  | 85 |  | — |  | (250,000) |  | (250,000) |
Share repurchase costs | — |  | — |  | — |  | — |  | — |  | (150) |  | (150) |
Balance at March 31, 2025 (as restated) | 79,464,252 |  | $ | 6,505 |  | $ | 7,037,344 |  | $ | 1,389 |  | $ | (173,191) |  | $ | 2,553,824 |  | $ | 9,425,871 |
Comprehensive income (net of tax): |  |  |  |  |  |  |
Net income (as restated) | — |  | — |  | — |  | — |  | — |  | 203,516 |  | 203,516 |
Currency translation adjustment | — |  | — |  | — |  | — |  | 104,428 |  | — |  | 104,428 |
Total Comprehensive Income (as restated) |  |  |  |  |  |  | 307,944 |
Exercise of share options | 17,901 |  | 1 |  | 1,733 |  | — |  | — |  | — |  | 1,734 |
Issue of restricted share units / performance share units | 7,158 |  | 1 |  | — |  | — |  | — |  | — |  | 1 |
Share based compensation expense | — |  | — |  | 15,251 |  | — |  | — |  | — |  | 15,251 |
Share issuance costs | — |  | — |  | (4) |  | — |  | — |  | — |  | (4) |
Repurchase of ordinary shares | (1,717,181) |  | (117) |  | — |  | 117 |  | — |  | (250,000) |  | (250,000) |
Share repurchase costs | — |  | — |  | — |  | — |  | — |  | (150) |  | (150) |
Balance at June 30, 2025 (as restated) | 77,772,130 |  | $ | 6,390 |  | $ | 7,054,324 |  | $ | 1,506 |  | $ | (68,763) |  | $ | 2,507,190 |  | $ | 9,500,647 |
Comprehensive loss (net of tax): |  |  |  |  |  |  |
Net loss (as restated) | — |  | — |  | — |  | — |  | — |  | (284,183) |  | (284,183) |
Currency translation adjustment | — |  | — |  | — |  | — |  | (18,181) |  | — |  | (18,181) |
Total Comprehensive Loss (as restated) |  |  |  |  |  |  | (302,364) |
Exercise of share options | 7,110 |  | — |  | 821 |  | — |  | — |  | — |  | 821 |
Issue of restricted share units / performance share units | 7,304 |  | — |  | — |  | — |  | — |  | — |  | — |
Share based compensation expense | — |  | — |  | 44,919 |  | — |  | — |  | — |  | 44,919 |
Share issuance costs | — |  | — |  | (5) |  | — |  | — |  | — |  | (5) |
Repurchase of ordinary shares | (1,426,612) |  | (100) |  | — |  | 100 |  | — |  | (250,000) |  | (250,000) |
Share repurchase costs | — |  | — |  | — |  | — |  | — |  | (150) |  | (150) |
Balance at September 30, 2025 (as restated) | 76,359,932 |  | $ | 6,290 |  | $ | 7,100,059 |  | $ | 1,606 |  | $ | (86,944) |  | $ | 1,972,857 |  | $ | 8,993,868 |

10

The following table presents summarized restated unaudited condensed Consolidated Statements of Cash Flows, including the balances originally reported in the Company's unaudited condensed consolidated financial statements for each of the year to date periods ended March 31, June 30, and September 30 of 2025.

ICON plc
CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED)
| Three Months Ended |  | Six Months Ended |  | Nine Months Ended
| March 31, 2025 |  | June 30, 2025 |  | September 30, 2025
| As Reported | Adjustments | As Restated |  | As Reported | Adjustments | As Restated |  | As Reported | Adjustments | As Restated
| (in thousands)
Cash flows provided by operating activities: |  |  |  |  |  |  |  |  |  |  |
Net income | $ | 154,151 |  | $ | 6,661 |  | $ | 160,812 |  |  | $ | 337,123 |  | $ | 27,205 |  | $ | 364,328 |  |  | $ | 339,478 |  | $ | (259,333) |  | $ | 80,145 |
Adjustments to reconcile net income to net cash provided by operating activities: |  |  |  |  |  |  |  |  |  |  |
Depreciation and amortization | 95,958 |  | — |  | 95,958 |  |  | 193,676 |  | — |  | 193,676 |  |  | 292,171 |  | 535 |  | 292,706 |
Goodwill impairment | — |  | — |  | — |  |  | — |  | — |  | — |  |  | 165,300 |  | 198,948 |  | 364,248 |
Impairment of non-financial assets | — |  | — |  | — |  |  | — |  | — |  | — |  |  | — |  | 101,027 |  | 101,027 |
Impairment of operating right-of-use assets and related property, plant and equipment | — |  | — |  | — |  |  | 5,573 |  | — |  | 5,573 |  |  | 5,573 |  | — |  | 5,573 |
Reduction in carrying value of operating right-of-use assets | 9,384 |  | — |  | 9,384 |  |  | 18,977 |  | — |  | 18,977 |  |  | 29,473 |  | — |  | 29,473 |
Amortization of financing costs and debt discount | 1,480 |  | — |  | 1,480 |  |  | 2,971 |  | — |  | 2,971 |  |  | 4,470 |  | — |  | 4,470 |
Stock compensation expense | 12,359 |  | — |  | 12,359 |  |  | 27,610 |  | — |  | 27,610 |  |  | 72,529 |  | — |  | 72,529 |
Deferred tax benefit | (25,014) |  | — |  | (25,014) |  |  | (46,095) |  | — |  | (46,095) |  |  | (91,788) |  | (22,469) |  | (114,257) |
Unrealized foreign exchange movements | 18,081 |  | — |  | 18,081 |  |  | 34,777 |  | — |  | 34,777 |  |  | 24,661 |  | — |  | 24,661 |
Other non-cash items | 8,240 |  | — |  | 8,240 |  |  | 15,266 |  | — |  | 15,266 |  |  | 20,561 |  | — |  | 20,561 |
Changes in operating assets and liabilities: |  |  |  |  |  |  |  |  |  |  |
Accounts receivable | 9,706 |  | (9,225) |  | 481 |  |  | 24,374 |  | (9,225) |  | 15,149 |  |  | 1,013 |  | (9,225) |  | (8,212) |
Unbilled revenue | 84,155 |  | (150,531) |  | (66,376) |  |  | 36,040 |  | (174,561) |  | (138,521) |  |  | 25,979 |  | (183,141) |  | (157,162) |
Unearned revenue | (122,305) |  | 145,768 |  | 23,463 |  |  | (122,306) |  | 148,067 |  | 25,761 |  |  | (101,089) |  | 165,631 |  | 64,542 |
Other net assets | 22,045 |  | 7,327 |  | 29,372 |  |  | (113,545) |  | 8,514 |  | (105,031) |  |  | 13,712 |  | 8,027 |  | 21,739 |
Net cash provided by operating activities | 268,240 |  | — |  | 268,240 |  |  | 414,441 |  | — |  | 414,441 |  |  | 802,043 |  | — |  | 802,043 |
Cash flows used in investing activities: |  |  |  |  |  |  |  |  |  |  |
Purchase of property, plant and equipment | (28,907) |  | — |  | (28,907) |  |  | (61,185) |  | — |  | (61,185) |  |  | (114,885) |  | — |  | (114,885) |
Purchase of subsidiary undertakings (net of cash acquired) | (2,537) |  | — |  | (2,537) |  |  | (2,537) |  | — |  | (2,537) |  |  | (2,537) |  | — |  | (2,537) |
Proceeds from investments in equity | 103 |  | — |  | 103 |  |  | 561 |  | — |  | 561 |  |  | 2,114 |  | — |  | 2,114 |
Purchase of investments in equity | (5,941) |  | — |  | (5,941) |  |  | (12,330) |  | — |  | (12,330) |  |  | (16,286) |  | — |  | (16,286) |
Net cash used in investing activities | (37,282) |  | — |  | (37,282) |  |  | (75,491) |  | — |  | (75,491) |  |  | (131,594) |  | — |  | (131,594) |

11

ICON plc
CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED)
| Three Months Ended |  | Six Months Ended |  | Nine Months Ended
| March 31, 2025 |  | June 30, 2025 |  | September 30, 2025
| As Reported | Adjustments | As Restated |  | As Reported | Adjustments | As Restated |  | As Reported | Adjustments | As Restated
| (in thousands)
Cash flows used in financing activities: |  |  |  |  |  |  |  |  |  |  |
Drawdown of credit lines and loan facilities | 50,000 |  | — |  | 50,000 |  |  | 50,000 |  | — |  | 50,000 |  |  | 50,000 |  | — |  | 50,000 |
Repayment of credit lines and loan facilities | (57,440) |  | — |  | (57,440) |  |  | (64,881) |  | — |  | (64,881) |  |  | (72,321) |  | — |  | (72,321) |
Proceeds from exercise of equity compensation | 4,763 |  | — |  | 4,763 |  |  | 6,498 |  | — |  | 6,498 |  |  | 7,319 |  | — |  | 7,319 |
Share issue costs | (5) |  | — |  | (5) |  |  | (9) |  | — |  | (9) |  |  | (14) |  | — |  | (14) |
Repurchase of ordinary shares | (250,000) |  | — |  | (250,000) |  |  | (500,000) |  | — |  | (500,000) |  |  | (750,000) |  | — |  | (750,000) |
Share repurchase costs | (150) |  | — |  | (150) |  |  | (300) |  | — |  | (300) |  |  | (450) |  | — |  | (450) |
Net cash used in financing activities | (252,832) |  | — |  | (252,832) |  |  | (508,692) |  | — |  | (508,692) |  |  | (765,466) |  | — |  | (765,466) |
|  | — |  |  |  |  | — |  |  |  |  | — |  |
Effect of exchange rate movements on cash | 9,787 |  | — |  | 9,787 |  |  | 21,353 |  | — |  | 21,353 |  |  | 25,120 |  | — |  | 25,120 |
Net decrease in cash and cash equivalents | (12,087) |  | — |  | (12,087) |  |  | (148,389) |  | — |  | (148,389) |  |  | (69,897) |  | — |  | (69,897) |
Cash and cash equivalents at beginning of year | 538,785 |  | — |  | 538,785 |  |  | 538,785 |  | — |  | 538,785 |  |  | 538,785 |  | — |  | 538,785 |
Cash and cash equivalents at end of period | $ | 526,698 |  | $ | — |  | $ | 526,698 |  |  | $ | 390,396 |  | $ | — |  | $ | 390,396 |  |  | $ | 468,888 |  | $ | — |  | $ | 468,888 |

12

The table below sets forth the unaudited condensed Consolidated Statements of Operations, including the balances originally reported in the Company’s unaudited condensed Consolidated financial statements, the effects of the adjustments made and the restated balances for each of the three months and year to date periods ended March 31, June 30, and September 30 of 2024.
ICON plc
CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (UNAUDITED)

| March 31, 2024 |  | June 30, 2024
| Three Months Ended |  | Three Months Ended |  | Six Months Ended
| As Reported | Adjustments | As Restated |  | As Reported | Adjustments | As Restated |  | As Reported | Adjustments | As Restated
| (in thousands, except share and per share data)
Revenue | $ | 2,090,386 |  | $ | (47,132) |  | $ | 2,043,254 |  |  | $ | 2,120,159 |  | $ | (78,233) |  | $ | 2,041,926 |  |  | $ | 4,210,545 |  | $ | (125,365) |  | $ | 4,085,180 |
Costs and expenses: |  |  |  |  |  |  |  |  |  |  |
Direct costs | 1,471,367 |  | (4,083) |  | 1,467,284 |  |  | 1,493,600 |  | (5,344) |  | 1,488,256 |  |  | 2,964,967 |  | (9,427) |  | 2,955,540 |
Selling, general and administrative | 177,350 |  | — |  | 177,350 |  |  | 194,458 |  | — |  | 194,458 |  |  | 371,808 |  | — |  | 371,808 |
Depreciation and amortization | 149,181 |  | — |  | 149,181 |  |  | 149,635 |  | — |  | 149,635 |  |  | 298,816 |  | — |  | 298,816 |
Transaction and integration related | 6,991 |  | — |  | 6,991 |  |  | 6,820 |  | — |  | 6,820 |  |  | 13,811 |  | — |  | 13,811 |
Restructuring | — |  | — |  | — |  |  | 45,789 |  | — |  | 45,789 |  |  | 45,789 |  | — |  | 45,789 |
Total costs and expenses | 1,804,889 |  | (4,083) |  | 1,800,806 |  |  | 1,890,302 |  | (5,344) |  | 1,884,958 |  |  | 3,695,191 |  | (9,427) |  | 3,685,764 |
Income from operations | 285,497 |  | (43,049) |  | 242,448 |  |  | 229,857 |  | (72,889) |  | 156,968 |  |  | 515,354 |  | (115,938) |  | 399,416 |
Interest income | 1,930 |  | — |  | 1,930 |  |  | 1,237 |  | — |  | 1,237 |  |  | 3,167 |  | — |  | 3,167 |
Interest expense | (71,665) |  | — |  | (71,665) |  |  | (60,840) |  | — |  | (60,840) |  |  | (132,505) |  | — |  | (132,505) |
Income before income tax expense | 215,762 |  | (43,049) |  | 172,713 |  |  | 170,254 |  | (72,889) |  | 97,365 |  |  | 386,016 |  | (115,938) |  | 270,078 |
Income tax expense | (28,324) |  | 3,948 |  | (24,376) |  |  | (23,344) |  | 8,755 |  | (14,589) |  |  | (51,668) |  | 12,703 |  | (38,965) |
Net income | $ | 187,438 |  | $ | (39,101) |  | $ | 148,337 |  |  | $ | 146,910 |  | $ | (64,134) |  | $ | 82,776 |  |  | $ | 334,348 |  | $ | (103,235) |  | $ | 231,113 |
Net income per ordinary share: |  |  |  |  |  |  |  |  |  |  |
Basic | $ | 2.27 |  |  | $ | 1.80 |  |  | $ | 1.78 |  |  | $ | 1.00 |  |  | $ | 4.04 |  |  | $ | 2.80 |
Diluted | $ | 2.25 |  |  | $ | 1.78 |  |  | $ | 1.76 |  |  | $ | 0.99 |  |  | $ | 4.02 |  |  | $ | 2.78 |
Weighted average number of ordinary shares outstanding: |  |  |  |  |  |  |  |  |  |
Basic | 82,579,203 |  |  | 82,579,203 |  |  | 82,738,765 |  |  | 82,738,765 |  |  | 82,658,984 |  |  | 82,658,984 |
Diluted | 83,249,303 |  |  | 83,249,303 |  |  | 83,360,841 |  |  | 83,360,841 |  |  | 83,260,144 |  |  | 83,260,144 |

13

ICON plc
CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (UNAUDITED)

| September 30, 2024 |  |  |  |  |  |
| Three Months Ended |  | Nine Months Ended |  |  |  |  |  |
| As Reported | Adjustments | As Restated |  | As Reported | Adjustments | As Restated |  |  |  |  |  |  |  |
| (in thousands, except share and per share data) |  |  |  |
Revenue | $ | 2,030,030 |  | $ | 11,913 |  | $ | 2,041,943 |  |  | $ | 6,240,575 |  | $ | (113,452) |  | $ | 6,127,123 |  |  |  |  |  |  |  |  |
Costs and expenses: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Direct costs | 1,438,616 |  | (5,222) |  | 1,433,394 |  |  | 4,403,583 |  | (14,649) |  | 4,388,934 |  |  |  |  |  |  |  |  |
Selling, general and administrative | 205,095 |  | — |  | 205,095 |  |  | 576,903 |  | — |  | 576,903 |  |  |  |  |  |  |  |  |
Depreciation and amortization | 93,029 |  | — |  | 93,029 |  |  | 391,845 |  | — |  | 391,845 |  |  |  |  |  |  |  |  |
Transaction and integration related | 7,856 |  | — |  | 7,856 |  |  | 21,667 |  | — |  | 21,667 |  |  |  |  |  |  |  |  |
Restructuring | — |  | — |  | — |  |  | 45,789 |  | — |  | 45,789 |  |  |  |  |  |  |  |  |
Total costs and expenses | 1,744,596 |  | (5,222) |  | 1,739,374 |  |  | 5,439,787 |  | (14,649) |  | 5,425,138 |  |  |  |  |  |  |  |  |
Income from operations | 285,434 |  | 17,135 |  | 302,569 |  |  | 800,788 |  | (98,803) |  | 701,985 |  |  |  |  |  |  |  |  |
Interest income | 2,434 |  | — |  | 2,434 |  |  | 5,601 |  | — |  | 5,601 |  |  |  |  |  |  |  |  |
Interest expense | (53,303) |  | — |  | (53,303) |  |  | (185,808) |  | — |  | (185,808) |  |  |  |  |  |  |  |  |
Income before income tax expense | 234,565 |  | 17,135 |  | 251,700 |  |  | 620,581 |  | (98,803) |  | 521,778 |  |  |  |  |  |  |  |  |
Income tax expense | (37,437) |  | (995) |  | (38,432) |  |  | (89,105) |  | 11,708 |  | (77,397) |  |  |  |  |  |  |  |  |
Net income | $ | 197,128 |  | $ | 16,140 |  | $ | 213,268 |  |  | $ | 531,476 |  | $ | (87,095) |  | $ | 444,381 |  |  |  |  |  |  |  |  |
Net income per ordinary share: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Basic | $ | 2.38 |  |  | $ | 2.57 |  |  | $ | 6.43 |  |  | $ | 5.37 |  |  |  |  |  |  |  |  |
Diluted | $ | 2.36 |  |  | $ | 2.56 |  |  | $ | 6.38 |  |  | $ | 5.33 |  |  |  |  |  |  |  |  |
Weighted average number of ordinary shares outstanding: |  |  |  |  |  |  |  |  |  |  |  |  |  |
Basic | 82,831,300 |  |  | 82,831,300 |  |  | 82,716,842 |  |  | 82,716,842 |  |  |  |  |  |  |  |  |
Diluted | 83,445,827 |  |  | 83,445,827 |  |  | 83,305,441 |  |  | 83,305,441 |  |  |  |  |  |  |  |  |

14

The table below sets forth the unaudited condensed Consolidated Statements of Comprehensive Income, including the balances originally reported in the Company’s unaudited condensed Consolidated financial statements, the effects of the adjustments made and the restated balances for each of the three months and year to date periods ended March 31, June 30, and September 30 of 2024.

ICON plc
CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED)
| March 31, 2024 |  | June 30, 2024
| Three Months Ended |  | Three Months Ended |  | Six Months Ended
| As Reported | Adjustments | As Restated |  | As Reported | Adjustments | As Restated |  | As Reported | Adjustments | As Restated
| (in thousands)
Net income | $ | 187,438 |  | $ | (39,101) |  | $ | 148,337 |  |  | $ | 146,910 |  | $ | (64,134) |  | $ | 82,776 |  |  | $ | 334,348 |  | $ | (103,235) |  | $ | 231,113 |
Other comprehensive income, net of tax: |  |  |  |  |  |  |  |  |  |  |
Currency translation adjustment | (32,040) |  | — |  | (32,040) |  |  | (8,985) |  | — |  | (8,985) |  |  | (41,025) |  | — |  | (41,025) |
Movement on cash flow hedge | 9,084 |  | — |  | 9,084 |  |  | (4,112) |  | — |  | (4,112) |  |  | 4,972 |  | — |  | 4,972 |
Total comprehensive income | $ | 164,482 |  | $ | (39,101) |  | $ | 125,381 |  |  | $ | 133,813 |  | $ | (64,134) |  | $ | 69,679 |  |  | $ | 298,295 |  | $ | (103,235) |  | $ | 195,060 |

ICON plc
CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED)
| September 30, 2024 |  |
| Three Months Ended |  | Nine Months Ended |  |
| As Reported | Adjustments | As Restated |  | As Reported | Adjustments | As Restated |  |  |  |
| (in thousands)
Net income | $ | 197,128 |  | $ | 16,140 |  | $ | 213,268 |  |  | $ | 531,476 |  | $ | (87,095) |  | $ | 444,381 |  |  |  |  |
Other comprehensive income, net of tax: |  |  |  |  |  |  |  |  |  |  |
Currency translation adjustment | 69,695 |  | — |  | 69,695 |  |  | 28,670 |  | — |  | 28,670 |  |  |  |  |
Movement on cash flow hedge | (198) |  | — |  | (198) |  |  | 4,774 |  | — |  | 4,774 |  |  |  |  |
Total comprehensive income | $ | 266,625 |  | $ | 16,140 |  | $ | 282,765 |  |  | $ | 564,920 |  | $ | (87,095) |  | $ | 477,825 |  |  |  |  |

15

The table below sets forth the unaudited condensed Consolidated Balance Sheets, including the balances originally reported in the Company’s unaudited condensed Consolidated financial statements, the effects of the adjustments made and the restated balances as at March 31, June 30, and September 30 of 2024.
ICON plc
CONDENSED CONSOLIDATED BALANCE SHEETS (UNAUDITED)

| March 31, 2024 |  | June 30, 2024 |  | September 30, 2024
| As Reported | Adjustments | As Restated |  | As Reported | Adjustments | As Restated |  | As Reported | Adjustments | As Restated
| (in thousands)
ASSETS |  |  |  |  |  |  |  |  |  |  |
Current assets: |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents | $ | 396,082 |  | $ | — |  | $ | 396,082 |  |  | $ | 506,553 |  | $ | — |  | $ | 506,553 |  |  | $ | 695,507 |  | $ | — |  | $ | 695,507 |
Available for sale investments | 1,955 |  | — |  | 1,955 |  |  | — |  | — |  | — |  |  | — |  | — |  | — |
Accounts receivable, net of allowance for credit losses | 1,862,468 |  | (159,949) |  | 1,702,519 |  |  | 1,569,642 |  | (990) |  | 1,568,652 |  |  | 1,396,080 |  | — |  | 1,396,080 |
Unbilled revenue | 993,141 |  | (43,574) |  | 949,567 |  |  | 1,230,948 |  | (209,429) |  | 1,021,519 |  |  | 1,361,198 |  | (242,338) |  | 1,118,860 |
Other receivables | 76,638 |  | — |  | 76,638 |  |  | 78,113 |  | — |  | 78,113 |  |  | 82,760 |  | — |  | 82,760 |
Prepayments and other current assets | 149,127 |  | — |  | 149,127 |  |  | 139,244 |  | — |  | 139,244 |  |  | 140,536 |  | — |  | 140,536 |
Income taxes receivable | 75,544 |  | — |  | 75,544 |  |  | 79,216 |  | — |  | 79,216 |  |  | 102,931 |  | — |  | 102,931 |
Total current assets | $ | 3,554,955 |  | $ | (203,523) |  | $ | 3,351,432 |  |  | $ | 3,603,716 |  | $ | (210,419) |  | $ | 3,393,297 |  |  | $ | 3,779,012 |  | $ | (242,338) |  | $ | 3,536,674 |
Non-current assets: |  |  |  |  |  |  |  |  |  |  |
Property, plant and equipment, net | 353,302 |  | — |  | 353,302 |  |  | 353,844 |  | — |  | 353,844 |  |  | 365,726 |  | — |  | 365,726 |
Goodwill | 9,018,301 |  | — |  | $ | 9,018,301 |  |  | 9,016,549 |  | — |  | 9,016,549 |  |  | 9,085,447 |  | — |  | 9,085,447 |
Intangible assets, net | 3,748,939 |  | — |  | 3,748,939 |  |  | 3,632,354 |  | — |  | 3,632,354 |  |  | 3,605,814 |  | — |  | 3,605,814 |
Operating right-of-use assets | 159,620 |  | — |  | 159,620 |  |  | 149,782 |  | — |  | 149,782 |  |  | 156,955 |  | — |  | 156,955 |
Other receivables | 87,193 |  | — |  | 87,193 |  |  | 87,609 |  | — |  | 87,609 |  |  | 88,445 |  | — |  | 88,445 |
Income taxes receivable | — |  | 4,155 |  | 4,155 |  |  | — |  | 14,994 |  | 14,994 |  |  | — |  | 13,682 |  | 13,682 |
Deferred tax asset | 74,777 |  | (1,431) |  | 73,346 |  |  | 74,787 |  | (2,463) |  | 72,324 |  |  | 75,993 |  | (2,306) |  | 73,687 |
Investments in equity | 51,164 |  | — |  | 51,164 |  |  | 50,220 |  | — |  | 50,220 |  |  | 53,720 |  | — |  | 53,720 |
Total Assets | $ | 17,048,251,000.00 |  | $ | (200,799) |  | $ | 16,847,452,000.00 |  |  | $ | 16,968,861,000.00 |  | $ | (197,888) |  | $ | 16,770,973,000.00 |  |  | $ | 17,211,112,000.00 |  | $ | (230,962) |  | $ | 16,980,150,000 |
LIABILITIES AND SHAREHOLDERS’ EQUITY |  |  |  |  |  |  |  |  |  |  |
Current liabilities: |  |  |  |  |  |  |  |  |  |  |
Accounts payable | $ | 113,579 |  | $ | — |  | $ | 113,579 |  |  | $ | 83,037 |  | $ | — |  | $ | 83,037 |  |  | $ | 106,172 |  | $ | — |  | $ | 106,172 |
Unearned revenue | 1,709,938 |  | (124,244) |  | 1,585,694 |  |  | 1,602,526 |  | (58,251) |  | 1,544,275 |  |  | 1,585,257 |  | (107,305) |  | 1,477,952 |
Other liabilities | 1,000,760 |  | (7,248) |  | 993,512 |  |  | 999,071 |  | (7,248) |  | 991,823 |  |  | 1,045,134 |  | (7,248) |  | 1,037,886 |
Income taxes payable | 41,905 |  | — |  | 41,905 |  |  | 27,935 |  | — |  | 27,935 |  |  | 52,585 |  | — |  | 52,585 |
Current bank credit lines, loan facilities and notes | 79,762 |  | — |  | 79,762 |  |  | 29,762 |  | — |  | 29,762 |  |  | 29,762 |  | — |  | 29,762 |
Total current liabilities | $ | 2,945,944 |  | $ | (131,492) |  | $ | 2,814,452 |  |  | $ | 2,742,331 |  | $ | (65,499) |  | $ | 2,676,832 |  |  | $ | 2,818,910 |  | $ | (114,553) |  | $ | 2,704,357 |

ICON plc
CONDENSED CONSOLIDATED BALANCE SHEETS (UNAUDITED)
16

| March 31, 2024 |  | June 30, 2024 |  | September 30, 2024
| As Reported | Adjustments | As Restated |  | As Reported | Adjustments | As Restated |  | As Reported | Adjustments | As Restated
| (in thousands)
Non-current liabilities: |  |  |  |  |  |  |  |  |  |  |
Non-current bank credit lines, loan facilities and notes, net | 3,419,734 |  | — |  | 3,419,734 |  |  | 3,408,157 |  | — |  | 3,408,157 |  |  | 3,402,368 |  | — |  | 3,402,368 |
Lease liabilities | 145,542 |  | — |  | 145,542 |  |  | 145,464 |  | — |  | 145,464 |  |  | 145,714 |  | — |  | 145,714 |
Non-current other liabilities | 45,988 |  | (752) |  | 45,236 |  |  | 48,372 |  | (752) |  | 47,620 |  |  | 50,157 |  | (752) |  | 49,405 |
Non-current income taxes payable | 188,876 |  | 871 |  | 189,747 |  |  | 195,778 |  | 2,313 |  | 198,091 |  |  | 201,135 |  | 2,093 |  | 203,228 |
Deferred tax liability | 869,520 |  | (1,028) |  | 868,492 |  |  | 843,633 |  | (1,418) |  | 842,215 |  |  | 818,329 |  | (1,358) |  | 816,971 |
Commitments and contingencies | — |  | — |  | — |  |  | — |  | — |  | — |  |  | — |  | — |  | — |
Total Liabilities | $ | 7,615,604 |  | $ | (132,401) |  | $ | 7,483,203 |  |  | $ | 7,383,735 |  | $ | (65,356) |  | $ | 7,318,379 |  |  | $ | 7,436,613 |  | $ | (114,570) |  | $ | 7,322,043 |
Shareholders' Equity: |  |  |  |  |  |  |  |  |  |  |
Ordinary shares par value 6 euro cents per share; 100,000,000 shares authorized |  |  |  |  |  |  |  |  |  |  |
82,683,805 shares issued and outstanding at March 31, 2024 (June 30, 2024: 82,816,600 and September 30, 2024: 82,559,366) | 6,711 |  | — |  | 6,711 |  |  | 6,720 |  | — |  | 6,720 |  |  | 6,703 |  | — |  | 6,703 |
Additional paid-in capital | 6,970,079 |  | — |  | 6,970,079 |  |  | 6,988,736 |  | — |  | 6,988,736 |  |  | 7,011,547 |  | — |  | 7,011,547 |
Other undenominated capital | 1,162 |  | — |  | 1,162 |  |  | 1,162 |  | — |  | 1,162 |  |  | 1,184 |  | — |  | 1,184 |
Accumulated other comprehensive loss | (166,462) |  | — |  | (166,462) |  |  | (179,559) |  | — |  | (179,559) |  |  | (110,062) |  | — |  | (110,062) |
Retained earnings | 2,621,157 |  | (68,398) |  | 2,552,759 |  |  | 2,768,067 |  | (132,532) |  | 2,635,535 |  |  | 2,865,127 |  | (116,392) |  | 2,748,735 |
Total Shareholders' Equity | $ | 9,432,647 |  | $ | (68,398) |  | $ | 9,364,249 |  |  | $ | 9,585,126 |  | $ | (132,532) |  | $ | 9,452,594 |  |  | $ | 9,774,499 |  | $ | (116,392) |  | $ | 9,658,107 |
Total Liabilities and Shareholders’ Equity | $ | 17,048,251,000 |  | $ | (200,799) |  | $ | 16,847,452,000 |  |  | $ | 16,968,861,000 |  | $ | (197,888) |  | $ | 16,770,973,000 |  |  | $ | 17,211,112,000 |  | $ | (230,962) |  | $ | 16,980,150 |

17

The following table presents summarized restated unaudited condensed Consolidated Statements of Shareholders’ Equity for three months ended March 31, June 30, and September 30 of 2024.

ICON plc
CONDENSED CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY (UNAUDITED)
| Number of Ordinary Shares | Ordinary Shares | Additional Paid-in Capital | Other Undenominated Capital | Accumulated Other Comprehensive Loss | Retained Earnings (As Restated) | Total
| ( in thousands, except share data)
Balance at December 31, 2023 (as restated) | 82,495,086 |  | $ | 6,699 |  | $ | 6,942,669 |  | $ | 1,162 |  | $ | (143,506) |  | $ | 2,404,422 |  | $ | 9,211,446 |
Comprehensive income, (net of tax): |  |  |  |  |  |  |
Net income (as restated) | — |  | — |  | — |  | — |  | — |  | 148,337 |  | 148,337 |
Currency translation adjustment | — |  | — |  | — |  | — |  | (32,040) |  | — |  | (32,040) |
Movement on cash flow hedge | — |  | — |  | — |  | — |  | 9,084 |  | — |  | 9,084 |
Total Comprehensive Income (as restated) |  |  |  |  |  |  | 125,381 |
Exercise of share options | 156,527 |  | 10 |  | 16,293 |  | — |  | — |  | — |  | 16,303 |
Issue of restricted share units / performance share units | 32,192 |  | 2 |  | — |  | — |  | — |  | — |  | 2 |
Share based compensation expense | — |  | — |  | 11,121 |  | — |  | — |  | — |  | 11,121 |
Share issuance costs | — |  | — |  | (4) |  | — |  | — |  | — |  | (4) |
Balance at March 31, 2024 (as restated) | 82,683,805 |  | $ | 6,711 |  | $ | 6,970,079 |  | $ | 1,162 |  | $ | (166,462) |  | $ | 2,552,759 |  | $ | 9,364,249 |
Comprehensive income, (net of tax): |  |  |  |  |  |  |
Net income (as restated) | — |  | — |  | — |  | — |  | — |  | 82,776 |  | 82,776 |
Currency translation adjustment | — |  | — |  | — |  | — |  | (8,985) |  | — |  | (8,985) |
Movement on cash flow hedge | — |  | — |  | — |  | — |  | (4,112) |  | — |  | (4,112) |
Total Comprehensive Income (as restated) |  |  |  |  |  |  | 69,679 |
Exercise of share options | 45,127 |  | 3 |  | 5,331 |  | — |  | — |  | — |  | 5,334 |
Issue of restricted share units / performance share units | 87,668 |  | 6 |  | — |  | — |  | — |  | — |  | 6 |
Share based compensation expense | — |  | — |  | 13,336 |  | — |  | — |  | — |  | 13,336 |
Share issuance costs | — |  | — |  | (10) |  | — |  | — |  | — |  | (10) |
Balance at June 30, 2024 (as restated) | 82,816,600 |  | $ | 6,720 |  | $ | 6,988,736 |  | $ | 1,162 |  | $ | (179,559) |  | $ | 2,635,535 |  | $ | 9,452,594 |
Comprehensive income, (net of tax): |  |  |  |  |  |  |
Net income (as restated) | — |  | — |  | — |  | — |  | — |  | 213,268 |  | 213,268 |
Currency translation adjustment | — |  | — |  | — |  | — |  | 69,695 |  | — |  | 69,695 |
Movement on cash flow hedge | — |  | — |  | — |  | — |  | (198) |  | — |  | (198) |
Total Comprehensive Income (as restated) |  |  |  |  |  |  | 282,765 |
Exercise of share options | 74,151 |  | 5 |  | 10,729 |  | — |  | — |  | — |  | 10,734 |
Issue of restricted share units / performance share units | 5,685 |  | — |  | — |  | — |  | — |  | — |  | — |
Share based compensation expense | — |  | — |  | 12,085 |  | — |  | — |  | — |  | 12,085 |
Share issuance costs | — |  | — |  | (3) |  | — |  | — |  | — |  | (3) |
Repurchase of ordinary shares | (337,070) |  | (22) |  | — |  | 22 |  | — |  | (100,000) |  | (100,000) |
Share repurchase costs | — |  | — |  | — |  | — |  | — |  | (68) |  | (68) |
Balance at September 30, 2024 (as restated) | 82,559,366 |  | $ | 6,703 |  | $ | 7,011,547 |  | $ | 1,184 |  | $ | (110,062) |  | $ | 2,748,735 |  | $ | 9,658,107 |

18

The following table presents summarized restated unaudited condensed Consolidated Statements of Cash Flows, including the balances originally reported in the Company's unaudited condensed consolidated financial statements for each of the year to date periods ended March 31, June 30, and September 30 of 2024.

ICON plc
CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED)
| Three Months Ended |  | Six Months Ended |  | Nine Months Ended
| March 31, 2024 |  | June 30, 2024 |  | September 30, 2024
| As Reported | Adjustments | As Restated |  | As Reported | Adjustments | As Restated |  | As Reported | Adjustments | As Restated
| (in thousands)
Cash flows provided by operating activities: |  |  |  |  |  |  |  |  |  |  |
Net income | $ | 187,438 |  | $ | (39,101) |  | $ | 148,337 |  |  | $ | 334,348 |  | $ | (103,235) |  | $ | 231,113 |  |  | $ | 531,476 |  | $ | (87,095) |  | $ | 444,381 |
Adjustments to reconcile net income to net cash provided by operating activities: |  |  |  |  |  |  |  |  |  |  |
Depreciation and amortization | 149,181 |  | — |  | 149,181 |  |  | 298,816 |  | — |  | 298,816 |  |  | 391,845 |  | — |  | 391,845 |
Impairment of operating right-of-use assets and related property, plant and equipment | — |  | — |  | — |  |  | 12,559 |  | — |  | 12,559 |  |  | 12,559 |  | — |  | 12,559 |
Reduction in carrying value of operating right-of-use assets | 11,472 |  | — |  | 11,472 |  |  | 19,367 |  | — |  | 19,367 |  |  | 29,820 |  | — |  | 29,820 |
Amortization of financing costs and debt discount | 3,907 |  | — |  | 3,907 |  |  | 20,604 |  | — |  | 20,604 |  |  | 22,066 |  | — |  | 22,066 |
Stock compensation expense | 13,181 |  | — |  | 13,181 |  |  | 28,145 |  | — |  | 28,145 |  |  | 41,183 |  | — |  | 41,183 |
Deferred tax benefit | (35,145) |  | 388 |  | (34,757) |  |  | (61,239) |  | 1,030 |  | (60,209) |  |  | (86,579) |  | 933 |  | (85,646) |
Unrealized foreign exchange movements | (1,027) |  | — |  | (1,027) |  |  | 13,761 |  | — |  | 13,761 |  |  | 34,018 |  | — |  | 34,018 |
Other non-cash items | 4,629 |  | — |  | 4,629 |  |  | 12,463 |  | — |  | 12,463 |  |  | 26,828 |  | — |  | 26,828 |
Changes in operating assets and liabilities: |  |  |  |  |  |  |  |  |  |  |
Accounts receivable | (80,431) |  | 134,031 |  | 53,600 |  |  | 198,749 |  | (24,928) |  | 173,821 |  |  | 352,795 |  | (25,918) |  | 326,877 |
Unbilled revenue | (42,546) |  | (54,781) |  | (97,327) |  |  | (287,183) |  | 111,074 |  | (176,109) |  |  | (423,533) |  | 143,983 |  | (279,550) |
Unearned revenue | 56,485 |  | (36,201) |  | 20,284 |  |  | (52,081) |  | 29,792 |  | (22,289) |  |  | (72,930) |  | (19,262) |  | (92,192) |
Other net assets | 59,932 |  | (4,336) |  | 55,596 |  |  | 7,356 |  | (13,733) |  | (6,377) |  |  | 88,790 |  | (12,641) |  | 76,149 |
Net cash provided by operating activities | 327,076 |  | — |  | 327,076 |  |  | 545,665 |  | — |  | 545,665 |  |  | 948,338 |  | — |  | 948,338 |
Cash flows used in investing activities: |  |  |  |  |  |  |  |  |  |  |
Purchase of property, plant and equipment | (27,152) |  | — |  | (27,152) |  |  | (63,440) |  | — |  | (63,440) |  |  | (106,772) |  | — |  | (106,772) |
Purchase of subsidiary undertakings (net of cash acquired) | (7,831) |  | — |  | (7,831) |  |  | (7,831) |  | — |  | (7,831) |  |  | (85,629) |  | — |  | (85,629) |
Movement of available for sale investments | (1) |  | — |  | (1) |  |  | 1,954 |  | — |  | 1,954 |  |  | 1,954 |  | — |  | 1,954 |
Proceeds from investments in equity | — |  | — |  | — |  |  | 1,373 |  | — |  | 1,373 |  |  | 2,671 |  | — |  | 2,671 |
Purchase of investments in equity | (4,381) |  | — |  | (4,381) |  |  | (5,621) |  | — |  | (5,621) |  |  | (10,131) |  | — |  | (10,131) |
Net cash used in investing activities | (39,365) |  | — |  | (39,365) |  |  | (73,565) |  | — |  | (73,565) |  |  | (197,907) |  | — |  | (197,907) |

19

ICON plc
CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED)
| Three Months Ended |  | Six Months Ended |  | Nine Months Ended
| March 31, 2024 |  | June 30, 2024 |  | September 30, 2024
| As Reported | Adjustments | As Restated |  | As Reported | Adjustments | As Restated |  | As Reported | Adjustments | As Restated
| (in thousands)
Cash flows used in financing activities: |  |  |  |  |  |  |  |  |  |  |
Debt issue costs | — |  | — |  | — |  |  | (11,679) |  | — |  | (11,679) |  |  | (12,678) |  | — |  | (12,678) |
Drawdown of credit lines and loan facilities | 50,000 |  | — |  | 50,000 |  |  | 2,192,480 |  | — |  | 2,192,480 |  |  | 2,242,480 |  | — |  | 2,242,480 |
Repayment of credit lines and loan facilities | (330,000) |  | — |  | (330,000) |  |  | (2,537,882) |  | — |  | (2,537,882) |  |  | (2,595,323) |  | — |  | (2,595,323) |
Proceeds from exercise of equity compensation | 16,305 |  | — |  | 16,305 |  |  | 21,645 |  | — |  | 21,645 |  |  | 32,379 |  | — |  | 32,379 |
Share issue costs | (4) |  | — |  | (4) |  |  | (14) |  | — |  | (14) |  |  | (17) |  | — |  | (17) |
Repurchase of ordinary shares | — |  | — |  | — |  |  | — |  | — |  | — |  |  | (100,000) |  | — |  | (100,000) |
Share repurchase costs | — |  | — |  | — |  |  | — |  | — |  | — |  |  | (68) |  | — |  | (68) |
Net cash used in financing activities | (263,699) |  | — |  | (263,699) |  |  | (335,450) |  | — |  | (335,450) |  |  | (433,227) |  | — |  | (433,227) |
Effect of exchange rate movements on cash | (6,032) |  | — |  | (6,032) |  |  | (8,199) |  | — |  | (8,199) |  |  | 201 |  | — |  | 201 |
Net increase in cash and cash equivalents | 17,980 |  | — |  | 17,980 |  |  | 128,451 |  | — |  | 128,451 |  |  | 317,405 |  | — |  | 317,405 |
Cash and cash equivalents at beginning of year | 378,102 |  | — |  | 378,102 |  |  | 378,102 |  | — |  | 378,102 |  |  | 378,102 |  | — |  | 378,102 |
Cash and cash equivalents at end of period | $ | 396,082 |  | $ | — |  | $ | 396,082 |  |  | $ | 506,553 |  | $ | — |  | $ | 506,553 |  |  | $ | 695,507 |  | $ | — |  | $ | 695,507 |

20

The table below sets forth the unaudited condensed Consolidated Statements of Operations, including the balances originally reported in the Company’s unaudited condensed Consolidated financial statements, the effects of the adjustments made and the restated balances for each of the three months and year to date periods ended March 31, June 30, and September 30 of 2023.
ICON plc
CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (UNAUDITED)

| March 31, 2023 |  | June 30, 2023
| Three Months Ended |  | Three Months Ended |  | Six Months Ended
| As Reported | Adjustments | As Restated |  | As Reported | Adjustments | As Restated |  | As Reported | Adjustments | As Restated
| (in thousands, except share and per share data)
Revenue | $ | 1,978,578 |  | $ | (12,770) |  | $ | 1,965,808 |  |  | $ | 2,020,251 |  | $ | (12,050) |  | $ | 2,008,201 |  |  | $ | 3,998,829 |  | $ | (24,820) |  | $ | 3,974,009 |
Costs and expenses: |  |  |  |  |  |  |  |  |  |  |
Direct costs | 1,395,546 |  | (3,624) |  | 1,391,922 |  |  | 1,429,540 |  | (3,134) |  | 1,426,406 |  |  | 2,825,086 |  | (6,758) |  | 2,818,328 |
Selling, general and administrative | 200,006 |  | — |  | 200,006 |  |  | 187,806 |  | — |  | 187,806 |  |  | 387,812 |  | — |  | 387,812 |
Depreciation and amortization | 145,126 |  | — |  | 145,126 |  |  | 145,059 |  | — |  | 145,059 |  |  | 290,185 |  | — |  | 290,185 |
Transaction and integration related | 11,382 |  | — |  | 11,382 |  |  | 12,701 |  | — |  | 12,701 |  |  | 24,083 |  | — |  | 24,083 |
Restructuring | 9,729 |  | — |  | 9,729 |  |  | 35,661 |  | — |  | 35,661 |  |  | 45,390 |  | — |  | 45,390 |
Total costs and expenses | 1,761,789 |  | (3,624) |  | 1,758,165 |  |  | 1,810,767 |  | (3,134) |  | 1,807,633 |  |  | 3,572,556 |  | (6,758) |  | 3,565,798 |
Income from operations | 216,789 |  | (9,146) |  | 207,643 |  |  | 209,484 |  | (8,916) |  | 200,568 |  |  | 426,273 |  | (18,062) |  | 408,211 |
Interest income | 1,072 |  | — |  | 1,072 |  |  | 949 |  | — |  | 949 |  |  | 2,021 |  | — |  | 2,021 |
Interest expense | (86,551) |  | — |  | (86,551) |  |  | (85,206) |  | — |  | (85,206) |  |  | (171,757) |  | — |  | (171,757) |
Income before income tax expense | 131,310 |  | (9,146) |  | 122,164 |  |  | 125,227 |  | (8,916) |  | 116,311 |  |  | 256,537 |  | (18,062) |  | 238,475 |
Income tax expense | (14,273) |  | 1,369 |  | (12,904) |  |  | (9,629) |  | 1,363 |  | (8,266) |  |  | (23,902) |  | 2,732 |  | (21,170) |
Income before share of losses from equity method investments | 117,037 |  | (7,777) |  | 109,260 |  |  | 115,598 |  | (7,553) |  | 108,045 |  |  | 232,635 |  | (15,330) |  | 217,305 |
Share of losses from equity method investments | (383) |  | — |  | (383) |  |  | — |  | — |  | — |  |  | (383) |  | — |  | (383) |
Net income | $ | 116,654 |  | $ | (7,777) |  | $ | 108,877 |  |  | $ | 115,598 |  | $ | (7,553) |  | $ | 108,045 |  |  | $ | 232,252 |  | $ | (15,330) |  | $ | 216,922 |
Net income per ordinary share: |  |  |  |  |  |  |  |  |  |  |
Basic | $ | 1.43 |  |  | $ | 1.33 |  |  | $ | 1.41 |  |  | $ | 1.32 |  |  | $ | 2.84 |  |  | $ | 2.65 |
Diluted | $ | 1.41 |  |  | $ | 1.32 |  |  | $ | 1.40 |  |  | $ | 1.31 |  |  | $ | 2.81 |  |  | $ | 2.63 |
Weighted average number of ordinary shares outstanding: |  |  |  |  |  |  |  |  |
Basic | 81,784,389 |  |  | 81,784,389 |  |  | 81,999,746 |  |  | 81,999,746 |  |  | 81,892,662 |  |  | 81,892,662 |
Diluted | 82,605,659 |  |  | 82,605,659 |  |  | 82,627,933 |  |  | 82,627,933 |  |  | 82,617,391 |  |  | 82,617,391 |

21

ICON plc
CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (UNAUDITED)

| September 30, 2023 |  |  |  |  |  |
| Three Months Ended |  | Nine Months Ended |  |  |  |  |  |
| As Reported | Adjustments | As Restated |  | As Reported | Adjustments | As Restated |  |  |  |  |  |  |  |
| (in thousands, except share and per share data) |  |  |  |
Revenue | $ | 2,055,099 |  | $ | (14,785) |  | $ | 2,040,314 |  |  | $ | 6,053,928 |  | $ | (39,605) |  | $ | 6,014,323 |  |  |  |  |  |  |  |  |
Costs and expenses: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Direct costs | 1,449,136 |  | (3,394) |  | 1,445,742 |  |  | 4,274,222 |  | (10,152) |  | 4,264,070 |  |  |  |  |  |  |  |  |
Selling, general and administrative | 185,187 |  | — |  | 185,187 |  |  | 572,999 |  | — |  | 572,999 |  |  |  |  |  |  |  |  |
Depreciation and amortization | 146,032 |  | — |  | 146,032 |  |  | 436,217 |  | — |  | 436,217 |  |  |  |  |  |  |  |  |
Transaction and integration related | 10,433 |  | — |  | 10,433 |  |  | 34,516 |  | — |  | 34,516 |  |  |  |  |  |  |  |  |
Restructuring | — |  | — |  | — |  |  | 45,390 |  | — |  | 45,390 |  |  |  |  |  |  |  |  |
Total costs and expenses | 1,790,788 |  | (3,394) |  | 1,787,394 |  |  | 5,363,344 |  | (10,152) |  | 5,353,192 |  |  |  |  |  |  |  |  |
Income from operations | 264,311 |  | (11,391) |  | 252,920 |  |  | 690,584 |  | (29,453) |  | 661,131 |  |  |  |  |  |  |  |  |
Interest income | 1,273 |  | — |  | 1,273 |  |  | 3,294 |  | — |  | 3,294 |  |  |  |  |  |  |  |  |
Interest expense | (83,908) |  | — |  | (83,908) |  |  | (255,665) |  | — |  | (255,665) |  |  |  |  |  |  |  |  |
Income before income tax expense | 181,676 |  | (11,391) |  | 170,285 |  |  | 438,213 |  | (29,453) |  | 408,760 |  |  |  |  |  |  |  |  |
Income tax expense | (18,011) |  | 1,627 |  | (16,384) |  |  | (41,913) |  | 4,359 |  | (37,554) |  |  |  |  |  |  |  |  |
Income before share of losses from equity method investments | 163,665 |  | (9,764) |  | 153,901 |  |  | 396,300 |  | (25,094) |  | 371,206 |  |  |  |  |  |  |  |  |
Share of losses from equity method investments | — |  | — |  | — |  |  | (383) |  | — |  | (383) |  |  |  |  |  |  |  |  |
Net income | $ | 163,665 |  | $ | (9,764) |  | $ | 153,901 |  |  | $ | 395,917 |  | $ | (25,094) |  | $ | 370,823 |  |  |  |  |  |  |  |  |
Net income per ordinary share: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Basic | $ | 1.99 |  |  | $ | 1.87 |  |  | $ | 4.83 |  |  | $ | 4.52 |  |  |  |  |  |  |  |  |
Diluted | $ | 1.97 |  |  | $ | 1.85 |  |  | $ | 4.79 |  |  | $ | 4.48 |  |  |  |  |  |  |  |  |
Weighted average number of ordinary shares outstanding: |  |  |  |  |  |  |  |  |  |  |  |  |  |
Basic | 82,215,627 |  |  | 82,215,627 |  |  | 82,001,500 |  |  | 82,001,500 |  |  |  |  |  |  |  |  |
Diluted | 82,972,888 |  |  | 82,972,888 |  |  | 82,737,073 |  |  | 82,737,073 |  |  |  |  |  |  |  |  |

22

The table below sets forth unaudited condensed Consolidated Statements of Comprehensive Income, including the balances originally reported in the Company’s unaudited condensed Consolidated financial statements, the effects of the adjustments made and the restated balances for each of the three months and year to date periods ended March 31, June 30, and September 30 of 2023.
ICON plc
CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED)

| March 31, 2023 |  | June 30, 2023
| Three Months Ended |  | Three Months Ended |  | Six Months Ended
| As Reported | Adjustments | As Restated |  | As Reported | Adjustments | As Restated |  | As Reported | Adjustments | As Restated
| (in thousands)
Net income | $ | 116,654 |  | $ | (7,777) |  | $ | 108,877 |  |  | $ | 115,598 |  | $ | (7,553) |  | $ | 108,045 |  |  | $ | 232,252 |  | $ | (15,330) |  | $ | 216,922 |
Other comprehensive income, net of tax: |  |  |  |  |  |  |  |  |  |  |
Currency translation adjustment | 15,500 |  | — |  | 15,500 |  |  | (10,638) |  | — |  | (10,638) |  |  | 4,862 |  | — |  | 4,862 |
Movement on cash flow hedge | (3,858) |  | — |  | (3,858) |  |  | 14,006 |  | — |  | 14,006 |  |  | 10,148 |  | — |  | 10,148 |
Total comprehensive income | $ | 128,296 |  | $ | (7,777) |  | $ | 120,519 |  |  | $ | 118,966 |  | $ | (7,553) |  | $ | 111,413 |  |  | $ | 247,262 |  | $ | (15,330) |  | $ | 231,932 |

ICON plc
CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED)
| September 30, 2023 |  |
| Three Months Ended |  | Nine Months Ended |  |
| As Reported | Adjustments | As Restated |  | As Reported | Adjustments | As Restated |  |  |  |
| (in thousands) |  |  |  |
Net income | $ | 163,665 |  | $ | (9,764) |  | $ | 153,901 |  |  | $ | 395,917 |  | $ | (25,094) |  | $ | 370,823 |  |  |  |  |
Other comprehensive income, net of tax: |  |  |  |  |  |  |  |  |  |  |
Currency translation adjustment | (38,648) |  | — |  | (38,648) |  |  | (33,786) |  | — |  | (33,786) |  |  |  |  |
Movement on cash flow hedge | 4,986 |  | — |  | 4,986 |  |  | 15,134 |  | — |  | 15,134 |  |  |  |  |
Total comprehensive income | $ | 130,003 |  | $ | (9,764) |  | $ | 120,239 |  |  | $ | 377,265 |  | $ | (25,094) |  | $ | 352,171 |  |  |  |  |

23

The table below sets forth the unaudited condensed Consolidated Balance Sheets, including the balances originally reported in the Company’s unaudited condensed Consolidated financial statements, the effects of the adjustments made and the restated balances as at March 31, June 30, and September 30 of 2023.

ICON plc
CONDENSED CONSOLIDATED BALANCE SHEETS (UNAUDITED)
| March 31, 2023 |  | June 30, 2023 |  | September 30, 2023
| As Reported | Adjustments | As Restated |  | As Reported | Adjustments | As Restated |  | As Reported | Adjustments | As Restated
| (in thousands)
ASSETS |  |  |  |  |  |  |  |  |  |  |
Current assets: |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents | $ | 279,880 |  | $ | — |  | $ | 279,880 |  |  | $ | 270,176 |  | $ | — |  | $ | 270,176 |  |  | $ | 313,065 |  | $ | — |  | $ | 313,065 |
Available for sale investments | 1,653 |  | — |  | 1,653 |  |  | 1,653 |  | — |  | 1,653 |  |  | 1,954 |  | — |  | 1,954 |
Accounts receivable, net of allowance for credit losses | 1,802,726 |  | — |  | 1,802,726 |  |  | 1,759,111 |  | — |  | 1,759,111 |  |  | 1,850,362 |  | — |  | 1,850,362 |
Unbilled revenue | 974,260 |  | (93,848) |  | 880,412 |  |  | 985,034 |  | (82,713) |  | 902,321 |  |  | 941,884 |  | (113,431) |  | 828,453 |
Other receivables | 143,727 |  | — |  | 143,727 |  |  | 129,101 |  | — |  | 129,101 |  |  | 121,687 |  | — |  | 121,687 |
Prepayments and other current assets | 170,167 |  | — |  | 170,167 |  |  | 152,774 |  | — |  | 152,774 |  |  | 150,193 |  | — |  | 150,193 |
Income taxes receivable | 56,820 |  | — |  | 56,820 |  |  | 70,021 |  | — |  | 70,021 |  |  | 42,039 |  | — |  | 42,039 |
Total current assets | $ | 3,429,233 |  | $ | (93,848) |  | $ | 3,335,385 |  |  | $ | 3,367,870 |  | $ | (82,713) |  | $ | 3,285,157 |  |  | $ | 3,421,184 |  | $ | (113,431) |  | $ | 3,307,753 |
Non-current assets: |  |  |  |  |  |  |  |  |  |  |
Property, plant and equipment, net | 348,106 |  | — |  | 348,106 |  |  | 346,521 |  | — |  | 346,521 |  |  | 342,262 |  | — |  | 342,262 |
Goodwill | 8,979,134 |  | — |  | 8,979,134 |  |  | 8,993,583 |  | — |  | 8,993,583 |  |  | 8,982,896 |  | — |  | 8,982,896 |
Intangible assets, net | 4,164,410 |  | — |  | 4,164,410 |  |  | 4,049,793 |  | — |  | 4,049,793 |  |  | 3,934,673 |  | — |  | 3,934,673 |
Operating right-of-use assets | 150,495 |  | — |  | 150,495 |  |  | 144,514 |  | — |  | 144,514 |  |  | 132,319 |  | — |  | 132,319 |
Other receivables | 71,612 |  | — |  | 71,612 |  |  | 64,140 |  | — |  | 64,140 |  |  | 52,797 |  | — |  | 52,797 |
Income taxes receivable | 22,076 |  | (4,352) |  | 17,724 |  |  | 25,169 |  | (3,576) |  | 21,593 |  |  | 40,481 |  | (2,651) |  | 37,830 |
Deferred tax asset | 89,406 |  | 439 |  | 89,845 |  |  | 80,772 |  | 876 |  | 81,648 |  |  | 83,095 |  | 1,398 |  | 84,493 |
Investments in equity | 32,052 |  | — |  | 32,052 |  |  | 35,298 |  | — |  | 35,298 |  |  | 41,790 |  | — |  | 41,790 |
Total Assets | $ | 17,286,524 |  | $ | (97,761) |  | $ | 17,188,763 |  |  | $ | 17,107,660 |  | $ | (85,413) |  | $ | 17,022,247 |  |  | $ | 17,031,497 |  | $ | (114,684) |  | $ | 16,916,813 |
LIABILITIES AND SHAREHOLDERS’ EQUITY |  |  |  |  |  |  |  |  |  |  |
Current liabilities: |  |  |  |  |  |  |  |  |  |  |
Accounts payable | 85,126 |  | — |  | 85,126 |  |  | 46,920 |  | — |  | 46,920 |  |  | 87,317 |  | — |  | 87,317 |
Unearned revenue | 1,580,235 |  | (99,960) |  | 1,480,275 |  |  | 1,573,311 |  | (79,908) |  | 1,493,403 |  |  | 1,663,183 |  | (99,235) |  | 1,563,948 |
Other liabilities | 1,029,893 |  | (7,248) |  | 1,022,645 |  |  | 994,883 |  | (7,248) |  | 987,635 |  |  | 948,829 |  | (7,248) |  | 941,581 |
Income taxes payable | 68,676 |  | (10,703) |  | 57,973 |  |  | 39,885 |  | (10,703) |  | 29,182 |  |  | 41,518 |  | (10,703) |  | 30,815 |
Current bank credit lines, loan facilities and notes | 135,150 |  | — |  | 135,150 |  |  | 105,150 |  | — |  | 105,150 |  |  | 130,150 |  | — |  | 130,150 |
Total current liabilities | $ | 2,899,080 |  | $ | (117,911) |  | $ | 2,781,169 |  |  | $ | 2,760,149 |  | $ | (97,859) |  | $ | 2,662,290 |  |  | $ | 2,870,997 |  | $ | (117,186) |  | $ | 2,753,811 |

24

ICON plc
CONDENSED CONSOLIDATED BALANCE SHEETS (UNAUDITED)
| March 31, 2023 |  | June 30, 2023 |  | September 30, 2023
| As Reported | Adjustments | As Restated |  | As Reported | Adjustments | As Restated |  | As Reported | Adjustments | As Restated
| (in thousands)
Non-current liabilities: |  |  |  |  |  |  |  |  |  |  |
Non-current bank credit lines, loan facilities and notes, net | 4,353,534 |  | — |  | 4,353,534 |  |  | 4,206,936 |  | — |  | 4,206,936 |  |  | 3,911,522 |  | — |  | 3,911,522 |
Lease liabilities | 133,048 |  | — |  | 133,048 |  |  | 129,079 |  | — |  | 129,079 |  |  | 121,424 |  | — |  | 121,424 |
Non-current other liabilities | 46,177 |  | (752) |  | 45,425 |  |  | 39,438 |  | (752) |  | 38,686 |  |  | 41,661 |  | (752) |  | 40,909 |
Non-current income taxes payable | 243,813 |  | — |  | 243,813 |  |  | 241,410 |  | — |  | 241,410 |  |  | 242,972 |  | — |  | 242,972 |
Deferred tax liability | 957,019 |  | (151) |  | 956,868 |  |  | 934,208 |  | (302) |  | 933,906 |  |  | 883,887 |  | (482) |  | 883,405 |
Commitments and contingencies | — |  | — |  | — |  |  | — |  | — |  | — |  |  | — |  | — |  | — |
Total Liabilities | $ | 8,632,671 |  | $ | (118,814) |  | $ | 8,513,857 |  |  | $ | 8,311,220 |  | $ | (98,913) |  | $ | 8,212,307 |  |  | $ | 8,072,463 |  | $ | (118,420) |  | $ | 7,954,043 |
Shareholders' Equity: |  |  |  |  |  |  |  |  |  |  |
Ordinary shares par value 6 euro cents per share; 100,000,000 shares authorized |  |  |  |  |  |  |  |  |  |  |
81,928,422 shares issued and outstanding at March 31, 2023 (June 30, 2023: 82,151,049 and September 30, 2023: 82,326,976) | 6,662 |  | — |  | 6,662 |  |  | 6,676 |  | — |  | 6,676 |  |  | 6,688 |  | — |  | 6,688 |
Additional paid-in capital | 6,867,887 |  | — |  | 6,867,887 |  |  | 6,891,494 |  | — |  | 6,891,494 |  |  | 6,924,073 |  | — |  | 6,924,073 |
Other undenominated capital | 1,162 |  | — |  | 1,162 |  |  | 1,162 |  | — |  | 1,162 |  |  | 1,162 |  | — |  | 1,162 |
Accumulated other comprehensive loss | (159,896) |  | — |  | (159,896) |  |  | (156,528) |  | — |  | (156,528) |  |  | (190,190) |  | — |  | (190,190) |
Retained earnings | 1,938,038 |  | 21,053 |  | 1,959,091 |  |  | 2,053,636 |  | 13,500 |  | 2,067,136 |  |  | 2,217,301 |  | 3,736 |  | 2,221,037 |
Total Shareholders' Equity | $ | 8,653,853 |  | $ | 21,053 |  | $ | 8,674,906 |  |  | $ | 8,796,440 |  | $ | 13,500 |  | $ | 8,809,940 |  |  | $ | 8,959,034 |  | $ | 3,736 |  | $ | 8,962,770 |
Total Liabilities and Shareholders’ Equity | $ | 17,286,524 |  | $ | (97,761) |  | $ | 17,188,763 |  |  | $ | 17,107,660 |  | $ | (85,413) |  | $ | 17,022,247 |  |  | $ | 17,031,497 |  | $ | (114,684) |  | $ | 16,916,813 |

25

The following table presents summarized restated unaudited condensed Consolidated Statements of Shareholders’ Equity for three months ended March 31, June 30, and September 30 of 2023.

ICON plc
CONDENSED CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY (UNAUDITED)
| Number of Ordinary Shares | Ordinary Shares | Additional Paid-in Capital | Other Undenominated Capital | Accumulated Other Comprehensive Loss | Retained Earnings (As Restated) | Total
| ( in thousands, except share data)
Balance at January 1, 2023 (as restated) | 81,723,555 |  | $ | 6,649 |  | $ | 6,840,306 |  | $ | 1,162 |  | $ | (171,538) |  | $ | 1,850,214 |  | $ | 8,526,793 |
Comprehensive income, (net of tax): |  |  |  |  |  |  |
Net income (as restated) | — |  | — |  | — |  | — |  | — |  | 108,877 |  | 108,877 |
Currency translation adjustment | — |  | — |  | — |  | — |  | 15,500 |  | — |  | 15,500 |
Movement on cash flow hedge | — |  | — |  | — |  | — |  | (3,858) |  | — |  | (3,858) |
Total Comprehensive Income (as restated) |  |  |  |  |  |  | 120,519 |
Exercise of share options | 136,649 |  | 9 |  | 12,927 |  | — |  | — |  | — |  | 12,936 |
Issue of restricted share units / performance share units | 68,218 |  | 4 |  | — |  | — |  | — |  | — |  | 4 |
Share based compensation expense | — |  | — |  | 14,658 |  | — |  | — |  | — |  | 14,658 |
Share issuance costs | — |  | — |  | (4) |  | — |  | — |  | — |  | (4) |
Balance at March 31, 2023 (as restated) | 81,928,422 |  | $ | 6,662 |  | $ | 6,867,887 |  | $ | 1,162 |  | $ | (159,896) |  | $ | 1,959,091 |  | $ | 8,674,906 |
Comprehensive income, (net of tax): |  |  |  |  |  |  |
Net income (as restated) | — |  | — |  | — |  | — |  | — |  | 108,045 |  | 108,045 |
Currency translation adjustment | — |  | — |  | — |  | — |  | (10,638) |  | — |  | (10,638) |
Movement on cash flow hedge | — |  | — |  | — |  | — |  | 14,006 |  | — |  | 14,006 |
Total Comprehensive Income (as restated) |  |  |  |  |  |  | 111,413 |
Exercise of share options | 93,304 |  | 6 |  | 7,223 |  | — |  | — |  | — |  | 7,229 |
Issue of restricted share units / performance share units | 129,323 |  | 8 |  | — |  | — |  | — |  | — |  | 8 |
Share based compensation expense | — |  | — |  | 16,389 |  | — |  | — |  | — |  | 16,389 |
Share issuance costs | — |  | — |  | (5) |  | — |  | — |  | — |  | (5) |
Balance at June 30, 2023 (as restated) | 82,151,049 |  | $ | 6,676 |  | $ | 6,891,494 |  | $ | 1,162 |  | $ | (156,528) |  | $ | 2,067,136 |  | $ | 8,809,940 |
Comprehensive income (net of tax): |  |  |  |  |  |  |
Net income (as restated) | — |  | — |  | — |  | — |  | — |  | 153,901 |  | 153,901 |
Currency translation adjustment | — |  | — |  | — |  | — |  | (38,648) |  | — |  | (38,648) |
Movement on cash flow hedge | — |  | — |  | — |  | — |  | 4,986 |  | — |  | 4,986 |
Total Comprehensive Income (as restated) |  |  |  |  |  |  | 120,239 |
Exercise of share options | 147,661 |  | 9 |  | 16,328 |  | — |  | — |  | — |  | 16,337 |
Issue of restricted share units / performance share units | 28,266 |  | 3 |  | — |  | — |  | — |  | — |  | 3 |
Share based compensation expense | — |  | — |  | 16,256 |  | — |  | — |  | — |  | 16,256 |
Share issuance costs | — |  | — |  | (5) |  | — |  | — |  | — |  | (5) |
Balance at September 30, 2023 (as restated) | 82,326,976 |  | $ | 6,688 |  | $ | 6,924,073 |  | $ | 1,162 |  | $ | (190,190) |  | $ | 2,221,037 |  | $ | 8,962,770 |

26

The following table presents summarized restated unaudited condensed Consolidated Statements of Cash Flows, including the balances originally reported in the Company's unaudited condensed consolidated financial statements for each of the year to date periods ended March 31, June 30, and September 30 of 2023.

ICON plc
CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED)
| Three Months Ended |  | Six Months Ended |  | Nine Months Ended
| March 31, 2023 |  | June 30, 2023 |  | September 30, 2023
| As Reported | Adjustments | As Restated |  | As Reported | Adjustments | As Restated |  | As Reported | Adjustments | As Restated
| (in thousands)
Cash flows provided by operating activities: |  |  |  |  |  |  |  |  |  |  |
Net income | $ | 116,654 |  | $ | (7,777) |  | $ | 108,877 |  |  | $ | 232,252 |  | $ | (15,330) |  | $ | 216,922 |  |  | $ | 395,917 |  | $ | (25,094) |  | $ | 370,823 |
Adjustments to reconcile net income to net cash provided by operating activities: |  |  |  |  |  |  |  |  |  |  |
Depreciation and amortization | 145,126 |  | — |  | 145,126 |  |  | 290,185 |  | — |  | 290,185 |  |  | 436,217 |  | — |  | 436,217 |
Impairment of operating right-of-use assets and related property, plant and equipment | 6,933 |  | — |  | 6,933 |  |  | 8,613 |  | — |  | 8,613 |  |  | 8,845 |  | — |  | 8,845 |
Reduction in carrying value of operating right-of-use assets | 11,304 |  | — |  | 11,304 |  |  | 23,607 |  | — |  | 23,607 |  |  | 33,979 |  | — |  | 33,979 |
Loss on equity method investments | 383 |  | — |  | 383 |  |  | 383 |  | — |  | 383 |  |  | 383 |  | — |  | 383 |
Acquisition-related gain | — |  | — |  | — |  |  | (6,160) |  | — |  | (6,160) |  |  | (6,160) |  | — |  | (6,160) |
Amortization of financing costs and debt discount | 4,497 |  | — |  | 4,497 |  |  | 7,899 |  | — |  | 7,899 |  |  | 12,485 |  | — |  | 12,485 |
Stock compensation expense | 14,759 |  | — |  | 14,759 |  |  | 31,357 |  | — |  | 31,357 |  |  | 47,303 |  | — |  | 47,303 |
Deferred tax benefit | (43,823) |  | (590) |  | (44,413) |  |  | (59,177) |  | (1,178) |  | (60,355) |  |  | (114,487) |  | (1,880) |  | (116,367) |
Unrealized foreign exchange movements | (1,319) |  | — |  | (1,319) |  |  | (3,345) |  | — |  | (3,345) |  |  | (7,670) |  | — |  | (7,670) |
Other non-cash items | 17,534 |  | — |  | 17,534 |  |  | 18,202 |  | — |  | 18,202 |  |  | 21,966 |  | — |  | 21,966 |
Changes in operating assets and liabilities: |  |  |  |  |  |  |  |  |  |  |
Accounts receivable | (93,259) |  | — |  | (93,259) |  |  | (40,675) |  | — |  | (40,675) |  |  | (139,096) |  | — |  | (139,096) |
Unbilled revenue | (18,346) |  | 109,105 |  | 90,759 |  |  | (27,210) |  | 97,970 |  | 70,760 |  |  | 14,370 |  | 128,688 |  | 143,058 |
Unearned revenue | 80,990 |  | (99,960) |  | (18,970) |  |  | 65,266 |  | (79,908) |  | (14,642) |  |  | 158,269 |  | (99,235) |  | 59,034 |
Other net assets | (65,933) |  | (778) |  | (66,711) |  |  | (161,816) |  | (1,554) |  | (163,370) |  |  | (141,425) |  | (2,479) |  | (143,904) |
Net cash provided by operating activities | 175,500 |  | — |  | 175,500 |  |  | 379,381 |  | — |  | 379,381 |  |  | 720,896 |  | — |  | 720,896 |

27

ICON plc
CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED)
| Three Months Ended |  | Six Months Ended |  | Nine Months Ended
| March 31, 2023 |  | June 30, 2023 |  | September 30, 2023
| As Reported | Adjustments | As Restated |  | As Reported | Adjustments | As Restated |  | As Reported | Adjustments | As Restated
| (in thousands)
Cash flows used in investing activities: |  | — |  |  |  |  |  |  |  |  |  |
Purchase of property, plant and equipment | (26,744) |  | — |  | (26,744) |  |  | (58,880) |  | — |  | (58,880) |  |  | (87,980) |  | — |  | (87,980) |
Purchase of subsidiary undertakings (net of cash acquired) | — |  | — |  | — |  |  | (5,100) |  | — |  | (5,100) |  |  | (5,100) |  | — |  | (5,100) |
Movement of available for sale investments | 60 |  | — |  | 60 |  |  | 60 |  | — |  | 60 |  |  | (241) |  | — |  | (241) |
Purchase of investments in equity | (1,358) |  | — |  | (1,358) |  |  | (4,733) |  | — |  | (4,733) |  |  | (10,829) |  | — |  | (10,829) |
Net cash used in investing activities | (28,042) |  | — |  | (28,042) |  |  | (68,653) |  | — |  | (68,653) |  |  | (104,150) |  | — |  | (104,150) |
Cash flows used in financing activities: |  |  |  |  |  |  |  |  |  |  |
Drawdown of credit lines and loan facilities | 180,000 |  | — |  | 180,000 |  |  | 230,000 |  | — |  | 230,000 |  |  | 305,000 |  | — |  | 305,000 |
Repayment of credit lines and loan facilities | (350,000) |  | — |  | (350,000) |  |  | (580,000) |  | — |  | (580,000) |  |  | (930,000) |  | — |  | (930,000) |
Proceeds from exercise of equity compensation | 12,940 |  | — |  | 12,940 |  |  | 20,177 |  | — |  | 20,177 |  |  | 36,517 |  | — |  | 36,517 |
Share issue costs | (4) |  | — |  | (4) |  |  | (9) |  | — |  | (9) |  |  | (14) |  | — |  | (14) |
Net cash used in financing activities | (157,064) |  | — |  | (157,064) |  |  | (329,832) |  | — |  | (329,832) |  |  | (588,497) |  | — |  | (588,497) |
Effect of exchange rate movements on cash | 718 |  | — |  | 718 |  |  | 512 |  | — |  | 512 |  |  | (3,952) |  | — |  | (3,952) |
Net (decrease)/increase in cash and cash equivalents | (8,888) |  | — |  | (8,888) |  |  | (18,592) |  | — |  | (18,592) |  |  | 24,297 |  | — |  | 24,297 |
Cash and cash equivalents at beginning of year | 288,768 |  | — |  | 288,768 |  |  | 288,768 |  | — |  | 288,768 |  |  | 288,768 |  | — |  | 288,768 |
Cash and cash equivalents at end of period | $ | 279,880 |  | $ | — |  | $ | 279,880 |  |  | $ | 270,176 |  | $ | — |  | $ | 270,176 |  |  | $ | 313,065 |  | $ | — |  | $ | 313,065 |

28

ICON plc
NOTES TO THE RESTATED CONDENSED CONSOLIDATED FINANCIAL STATEMENTS
(UNAUDITED)
1. 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.
29

2. 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 |

30

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.
31

3. Goodwill
The change in the carrying amount of goodwill between December 31, 2024 and September 30, 2025 is as follows:

| Nine Months Ended |  |
| September 30, 2025 (As Restated) |  |
| (in thousands) |
Opening balance at December 31, 2024 | $ | 9,051,410 |  |  |
Prior period acquisitions | 5,108 |  |  |
Impairment | (364,248) |  |  |
Foreign exchange movement | 36,105 |  |  |
Closing balance | $ | 8,728,375 |  |  |

The Company completed its assessment for impairment as at September 30, 2025, performing a quantitative assessment using a discounted cash flow method under the income approach to estimate the fair values of each reporting unit. As a result of this impairment test of goodwill, a non-cash goodwill impairment charge of $364.2 million was identified in respect of the Data Solutions Reporting Unit. The Company performed a quantitative impairment assessment using a discounted cash flow method under the income approach to estimate the fair values of each reporting unit, no impairment was identified in the Company’s other reporting units.
32

4. Intangible assets
The carrying amount of Intangible Assets as of September 30, 2025 is as follows:

| September 30, 2025 (As Restated) |
| (in thousands)
Cost |  |
Customer relationships | $ | 4,134,107 |  |
Order backlog | 545,922 |  |
Trade names & brands | 204,713 |  |
Patient database | 170,487 |  |
Technology assets | 151,691 |  |
Total cost | 5,206,920 |  |
Accumulated amortization | (1,822,598) |  |
Impairment | (86,739) |  |
Net book value | $ | 3,297,583 |  |

In the three months ended September 30, 2025, the amortization expense recognized by the Company was $58.7 million (three months ended September 30, 2024: $58.0 million).
In the nine months ended September 30, 2025, the amortization expense recognized by the Company was $176.7 million (nine months ended September 30, 2024: $291.0 million).
An impairment indicator was identified specific to the Company's Data Solutions reporting unit that indicated the carrying amount of the intangible assets in the Data Solutions reporting unit may not be recoverable. This indicator related to the Company’s revised expectations on the future performance of the reporting unit considering specific external market participant factors. As a result, the Company assessed the fair value of the intangible assets based on estimated future discounted cash flows and recorded an impairment charge of $86.7 million.
There were no additions to intangible assets during the nine months ended September 30, 2025.
33

5. Business Segment and Geographical Information
The geographical distribution of the Company’s segment measures for each of the quarters ended March 31, June 30 and September 30, 2025; March 31, June 30 and September 30, 2024; and March 31, June 30 and September 30, 2023 is as follows:
a) The distribution of revenue by geographical area was as follows:

| Three Months Ended March 31,
| 2025 (As Restated) | 2024 (As Restated) | 2023 (As Restated)
| (in thousands)
Ireland | $ | 734,340 |  | $ | 607,286 |  | $ | 500,174 |
Rest of Europe | 375,865 |  | 389,603 |  | 413,851 |
U.S. | 672,424 |  | 808,364 |  | 843,666 |
Rest of World | 232,691 |  | 238,001 |  | 208,117 |
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)
Ireland | $ | 902,026 |  | $ | 627,500 |  | $ | 582,403 |  | $ | 1,636,366 |  | $ | 1,234,786 |  | $ | 1,082,577 |
Rest of Europe | 360,070 |  | 383,199 |  | 373,460 |  | 735,935 |  | 772,802 |  | 787,311 |
U.S. | 573,395 |  | 790,510 |  | 847,322 |  | 1,245,819 |  | 1,598,874 |  | 1,690,988 |
Rest of World | 203,597 |  | 240,717 |  | 205,016 |  | 436,288 |  | 478,718 |  | 413,133 |
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)
Ireland | $ | 801,771 |  | $ | 627,432 |  | $ | 582,839 |  | $ | 2,438,137 |  | $ | 1,862,218 |  | $ | 1,665,416 |
Rest of Europe | 399,035 |  | 420,759 |  | 384,289 |  | 1,134,970 |  | 1,193,561 |  | 1,171,600 |
U.S. | 649,040 |  | 755,383 |  | 830,934 |  | 1,894,859 |  | 2,354,257 |  | 2,521,922 |
Rest of World | 234,569 |  | 238,369 |  | 242,252 |  | 670,857 |  | 717,087 |  | 655,385 |
Total | $ | 2,084,415 |  | $ | 2,041,943 |  | $ | 2,040,314 |  | $ | 6,138,823 |  | $ | 6,127,123 |  | $ | 6,014,323 |

34

b) The distribution of income from operations by geographical area was as follows:

| Three Months Ended March 31,
| 2025 (As Restated) | 2024 (As Restated) | 2023 (As Restated)
| (in thousands)
Ireland | $ | 163,378 |  | $ | 210,497 |  | $ | 156,422 |
Rest of Europe | 36,843 |  | 53,197 |  | 59,690 |
U.S. | 68,487 |  | 76,848 |  | 88,561 |
Rest of World | 17,208 |  | 18,404 |  | 17,648 |
Sub-total | $ | 285,916 |  | $ | 358,946 |  | $ | 322,321 |
Amortization of intangible assets | (58,946) |  | (116,498) |  | (114,678) |
Total | $ | 226,970 |  | $ | 242,448 |  | $ | 207,643 |

| 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)
Ireland | $ | 199,606 |  | $ | 153,450 |  | $ | 231,085 |  | $ | 362,984 |  | $ | 363,947 |  | $ | 387,507 |
Rest of Europe | 7,978 |  | 38,910 |  | 22,430 |  | 44,821 |  | 92,107 |  | 82,120 |
U.S. | 72,234 |  | 61,861 |  | 56,251 |  | 140,721 |  | 138,709 |  | 144,812 |
Rest of World | 10,178 |  | 19,236 |  | 5,419 |  | 27,386 |  | 37,640 |  | 23,067 |
Sub-total | $ | 289,996 |  | $ | 273,457 |  | $ | 315,185 |  | $ | 575,912 |  | $ | 632,403 |  | $ | 637,506 |
Amortization of intangible assets | (59,057) |  | (116,489) |  | (114,617) |  | (118,003) |  | (232,987) |  | (229,295) |
Total | $ | 230,939 |  | $ | 156,968 |  | $ | 200,568 |  | $ | 457,909 |  | $ | 399,416 |  | $ | 408,211 |

| 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)
Ireland | $ | 164,983 |  | $ | 228,554 |  | $ | 224,324 |  | $ | 527,967 |  | $ | 592,501 |  | $ | 611,831 |
Rest of Europe | 51,040 |  | 55,194 |  | 56,569 |  | 95,861 |  | 147,301 |  | 138,689 |
U.S. | 68,182 |  | 59,610 |  | 70,320 |  | 208,903 |  | 198,319 |  | 215,132 |
Rest of World | 16,848 |  | 17,237 |  | 16,280 |  | 44,234 |  | 54,877 |  | 39,347 |
Sub-total | $ | 301,053 |  | $ | 360,595 |  | $ | 367,493 |  | $ | 876,965 |  | $ | 992,998 |  | $ | 1,004,999 |
Amortization of intangible assets | (58,688) |  | (58,026) |  | (114,573) |  | (176,691) |  | (291,013) |  | (343,868) |
Goodwill impairment | (364,248) |  | — |  | — |  | (364,248) |  | — |  | — |
Impairment of non-financial assets | (101,027) |  | — |  | — |  | (101,027) |  | — |  | — |
Total | $ | (222,910) |  | $ | 302,569 |  | $ | 252,920 |  | $ | 234,999 |  | $ | 701,985 |  | $ | 661,131 |

35

Management’s discussion and analysis of financial condition and results of operations
Restatement of Previously Issued Condensed Consolidated Financial Statements
The following management's discussion and analysis of financial condition and results of operations updates the corresponding discussions in the Affected Form 6-K Reports to give effect to the restatement of the Company's previously issued unaudited condensed consolidated financial statements and related disclosures included in the Affected Form 6-K Reports. The following should be read in conjunction with the audited consolidated financial statements and related footnotes included in our Form 20-F.
Detailed restatements of the Company’s consolidated financial statements for the years ended December 31, 2024 and December 31, 2023 are provided in Note 1A. Restatement of Previously Issued Consolidated Financial Statements in the Notes to the Consolidated Financial Statements of our Form 20-F.
Quarterly Results of Operations (Unaudited)
The following tables set forth our unaudited quarterly consolidated financial data for the fiscal quarters ended March 31, June 30, and September 30, 2025; March 31, June 30, and September 30, 2024 and March 31, June 30, and September 30, 2023. We have prepared the quarterly data on a basis consistent with our audited consolidated financial statements included in our Form 20-F and include, in our opinion, all adjustments necessary for a fair statement of the financial information contained in those statements. This information should be read in conjunction with the consolidated financial statements and related notes included elsewhere in this Form 6-K/A and our Form 20-F. The results of historical periods are not necessarily indicative of the results of operations for a full year or any future period.
Three months ended March 31, 2025 compared to three months ended March 31, 2024; and three months ended March 31, 2024 compared to three months ended March 31, 2023.

| Three Months Ended March 31,
| Percentage of Revenue | Percentage Change
| 2025 (As Restated) | 2024 (As Restated) | 2023 (As Restated) | 2025 vs 2024 (As Restated) | 2024 vs 2023 (As Restated)
Revenue | 100.0 | % | 100.0 | % | 100.0 | % | (1.4) | % | 3.9 | %
Costs and expenses: |  |  |  |  |
Direct costs | 71.9 | % | 71.8 | % | 70.8 | % | (1.2) | % | 5.4 | %
Selling, general and administrative expense | 9.8 | % | 8.7 | % | 10.2 | % | 11.9 | % | (11.3) | %
Depreciation | 1.8 | % | 1.6 | % | 1.5 | % | 13.2 | % | 7.3 | %
Amortization | 2.9 | % | 5.7 | % | 5.8 | % | (49.4) | % | 1.6 | %
Transaction and integration related | 0.3 | % | 0.3 | % | 0.6 | % | (22.7) | % | (38.6) | %
Restructuring | 2.0 | % | — | % | 0.5 | % | NM | NM
Income from operations | 11.3 | % | 11.9 | % | 10.6 | % | (6.4) | % | 16.8 | %

*NM – Not Meaningful

| Three Months Ended March 31,
| Change
(in thousands) | 2025 (As Restated) | 2024 (As Restated) | 2023 (As Restated) | 2025 vs 2024 (As Restated) | 2024 vs 2023 (As Restated)
Revenue | $ | 2,015,320 |  | $ | 2,043,254 |  | $ | 1,965,808 |  | $ | (27,934) |  | (1.4) | % | $ | 77,446 |  | 3.9 | %
Costs and expenses: |  |  |  |  |  |  |
Direct costs | 1,449,258 |  | 1,467,284 |  | 1,391,922 |  | (18,026) |  | (1.2) | % | 75,362 |  | 5.4 | %
Selling, general and administrative expense | 198,384 |  | 177,350 |  | 200,006 |  | 21,034 |  | 11.9 | % | (22,656) |  | (11.3) | %
Depreciation | 37,012 |  | 32,683 |  | 30,448 |  | 4,329 |  | 13.2 | % | 2,235 |  | 7.3 | %
Amortization | 58,946 |  | 116,498 |  | 114,678 |  | (57,552) |  | (49.4) | % | 1,820 |  | 1.6 | %
Transaction and integration related | 5,404 |  | 6,991 |  | 11,382 |  | (1,587) |  | (22.7) | % | (4,391) |  | (38.6) | %
Restructuring | 39,346 |  | — |  | 9,729 |  | 39,346 |  | NM | (9,729) |  | NM
Income from operations | $ | 226,970 |  | $ | 242,448 |  | $ | 207,643 |  | $ | (15,478) |  | (6.4) | % | $ | 34,805 |  | 16.8 | %

36

Revenue (as restated)
Revenue for the three months ended March 31, 2025 decreased by $27.9 million, or 1.4%, to $2,015.3 million, compared to $2,043.3 million for the three months ended March 31, 2024. Revenue for the three months ended March 31, 2024 increased by $77.4 million, or 3.9%, to $2,043.3 million, compared to $1,965.8 million for the three months ended March 31, 2023. Revenue for the three months ended March 31, 2025 decreased by 0.2% in constant currency terms compared to the three months ended March 31, 2024. Revenue for the three months ended March 31, 2024 increased by 3.7% in constant currency terms compared to the three months ended March 31, 2023. Revenue for the three months ended March 31, 2025 was impacted by the volatility and cautiousness present in the broader clinical development market. The increase in revenue for the three months ended March 31, 2024 is due to continued organic growth across the Company's markets.
During the three months ended March 31, 2025, we derived 33.4%, 55.1% and 11.5% of our revenue in the United States, Europe and Rest of World respectively. During the three months ended March 31, 2024, we derived 39.6%, 48.8% and 11.6% of our revenue in the United States, Europe and Rest of World respectively and for the three months ended March 31, 2023, we derived 42.9%, 46.5% and 10.6% of our revenue in the United States, Europe and Rest of World respectively. Revenues from our top five customers amounted to $496.1 million, $539.0 million and $567.9 million in the three months ended March 31, 2025, March 31, 2024 and March 31, 2023 respectively or 24.6%, 26.4% and 28.9% of total revenue respectively. New customer accounts are continually added across the full portfolio of large pharma customers, mid-tier pharma customers and biotech customers.
Revenue in Ireland increased by $127.0 million or 20.9% for the three months ended March 31, 2025, to $734.3 million, compared to $607.3 million for the three months ended March 31, 2024 and increased by $107.1 million or 21.4% for the three months ended March 31, 2024, to $607.3 million, compared to $500.2 million for the three months ended March 31, 2023. Revenue in Ireland during the three months ended March 31, 2025 increased by 20.9% compared to an overall decrease in Group revenue of 1.4%, and during the three months ended March 31, 2024, revenue in Ireland increased by 21.4% compared to an overall increase in Group revenue of 3.9%. Revenue in Ireland is principally a function of our global contracting model.
Revenue in our Rest of Europe region decreased by $13.7 million or 3.5% for the three months ended March 31, 2025, to $375.9 million compared to $389.6 million for the three months ended March 31, 2024 and decreased by $24.3 million or 5.9% for three months ended March 31, 2024 to $389.6 million, compared to $413.9 million for the three months ended March 31, 2023.
Revenue in the U.S. region decreased by $136.0 million or 16.8% for the three months ended March 31, 2025, to $672.4 million, compared to $808.4 million for the three months ended March 31, 2024 and decreased by $35.3 million or 4.2% for three months ended March 31, 2024, to $808.4 million, compared to $843.7 million for the three months ended March 31, 2023.
Revenue in the Rest of World region decreased by $5.3 million or 2.2% for the three months ended March 31, 2025, to $232.7 million, compared to $238.0 million for the three months ended March 31, 2024. Revenue increased by $30.0 million or 14.4% for three months ended March 31, 2024 to $238.0 million, compared to $208.0 million for the three months ended March 31, 2023.
Direct costs (as restated)
Direct costs for the three months ended March 31, 2025 decreased by $18.0 million, or 1.2%, to $1,449.3 million compared to $1,467.3 million for the three months ended March 31, 2024. Direct costs consist primarily of investigator and other reimbursable costs, compensation, associated fringe benefits and share based compensation expense for project-related employees and other direct project driven costs. The decrease in direct costs arose due to a decrease in personnel related costs and travel, partially offset by increases in third party investigator/other reimbursable costs, laboratories and other direct project driven costs. As a percentage of revenue, direct costs increased to 71.9% of revenue during the three months ended March 31, 2025 compared to 71.8% for the three months ended March 31, 2024.
Direct costs for the three months ended March 31, 2024 increased by $75.4 million, or 5.4%, to $1,467.3 million compared to $1,391.9 million for the three months ended March 31, 2023. The increase in direct costs arose due to an increase in personnel related costs, laboratory costs, third party investigator/other reimbursable costs, travel and other direct project driven costs. As a percentage of revenue, direct costs increased to 71.8% of revenue during the three months ended March 31, 2024 compared to 70.8% for the three months ended March 31, 2023.
37

Income from operations (as restated)
Income from operations for the three months ended March 31, 2025 decreased by $15.5 million or 6.4% to $227.0 million compared to $242.4 million for the three months ended March 31, 2024. As a percentage of revenue, income from operations decreased to 11.3% for the three months ended March 31, 2025 compared to 11.9% of revenue for the three months ended March 31, 2024. Income from operations for the three months ended March 31, 2024 increased by $34.8 million or 16.8% to $242.4 million compared to $207.6 million for the three months ended March 31, 2023. As a percentage of revenue, income from operations for the three months ended March 31, 2024 increased to 11.9% compared to 10.6% of revenue for the three months ended March 31, 2023.
Excluding amortization of intangible assets, income from operations in Ireland for three months ended March 31, 2025 decreased to $163.4 million compared to $210.5 million for the three months ended March 31, 2024; and increased to $210.5 million for three months ended March 31, 2024 compared to $156.4 million for the three months ended March 31, 2023. As a percentage of revenue, excluding amortization of intangible assets, income from operations in Ireland for the three months ended March 31, 2025 decreased to 22.2% compared to 34.7% for three months ended March 31, 2024; and increased to 34.7% for the three months ended March 31, 2024 compared to 31.3% for the three months ended March 31, 2023.
In the Rest of Europe region, excluding amortization of intangible assets, income from operations for three months ended March 31, 2025 decreased to $36.8 million compared to $53.2 million for the three months ended March 31, 2024; and decreased to $53.2 million for three months ended March 31, 2024 compared to $59.7 million for the three months ended March 31, 2023. As a percentage of revenue, excluding amortization of intangible assets, income from operations in the Rest of Europe region for three months ended March 31, 2025 decreased to 9.8% compared to 13.7% for the three months ended March 31, 2024 and decreased to 13.7% for the three months ended March 31, 2024 compared to 14.4% for the three months ended March 31, 2023.
In the U.S. region, income from operations, excluding amortization of intangible assets for three months ended March 31, 2025 decreased to $68.5 million compared to $76.8 million for the three months ended March 31, 2024; and decreased to $76.8 million for three months ended March 31, 2024 compared to $88.6 million for the three months ended March 31, 2023. As a percentage of revenue, excluding amortization of intangible assets, income from operations in the U.S. region for three months ended March 31, 2025 increased to 10.2% compared to 9.5% for the three months ended March 31, 2024; and decreased to 9.5% for the three months ended March 31, 2024 compared to 10.5% for the three months ended March 31, 2023.
In Rest of World region, income from operations, excluding amortization of intangible assets, for three months ended March 31, 2025 decreased to $17.2 million compared to $18.4 million for the three months ended March 31, 2024; and increased to $18.4 million for three months ended March 31, 2024 compared to $17.6 million for the three months ended March 31, 2023. As a percentage of revenue, excluding amortization of intangible assets, income from operations in Rest of World regions for three months ended March 31, 2025 decreased to 7.4% compared to 7.7% for the three months ended March 31, 2024; and decreased to 7.7% for the three months ended March 31, 2024 compared to 8.5% for the three months ended March 31, 2023.
Income tax expense (as restated)

| Three Months Ended March 31,
|  |  |  | Change
(in thousands) | 2025 (As Restated) | 2024 (As Restated) | 2023 (As Restated) | 2025 vs 2024 (As Restated) | 2024 vs 2023 (As Restated)
Income tax expense | $ | 20,351 |  | $ | 24,376 |  | $ | 12,904 |  | $ | (4,025) |  | $ | 11,472 |
Effective income tax rate | 11.2 | % | 14.1 | % | 10.6 | % | (2.9) | % | 3.5 | %

Income tax expense decreased to $20.4 million charge for the three months ended March 31, 2025 compared to a $24.4 million charge for the three months ended March 31, 2024. The Company’s effective tax rate for the three months ended March 31, 2025 was 11.2% compared with 14.1% for the three months ended March 31, 2024 primarily due to changes in various tax laws and the level of deferred tax benefit associated with the amortization of intangible assets.
Income tax expense increased to a $24.4 million charge for the three months ended March 31, 2024 compared to a $12.9 million charge for the three months ended March 31, 2023. The Company’s effective tax rate for the three months ended March 31, 2024 was 14.1% compared with 10.6% for the three months ended March 31, 2023 primarily due to changes in various tax laws
With the exception of the foregoing, the Company’s effective tax rate remains principally a function of the distribution of pre-tax profits amongst the territories in which it operates.
38

Three months ended June 30, 2025 compared to three months ended June 30, 2024; and three months ended June 30, 2024 compared to three months ended June 30, 2023.

| Three Months Ended June 30,
| Percentage of Revenue | Percentage Change
| 2025 (As Restated) | 2024 (As Restated) | 2023 (As Restated) | 2025 vs 2024 (As Restated) | 2024 vs 2023 (As Restated)
Revenue | 100.0 | % | 100.0 | % | 100.0 | % | (0.1) | % | 1.7 | %
Costs and expenses: |  |  |  |  |
Direct costs | 71.4 | % | 72.9 | % | 71.0 | % | (2.2) | % | 4.3 | %
Selling, general and administrative expense | 10.1 | % | 9.6 | % | 9.4 | % | 5.4 | % | 3.5 | %
Depreciation | 1.9 | % | 1.6 | % | 1.5 | % | 16.6 | % | 8.9 | %
Amortization | 2.9 | % | 5.7 | % | 5.7 | % | (49.3) | % | 1.6 | %
Transaction and integration related | 0.3 | % | 0.3 | % | 0.6 | % | (1.5) | % | (46.3) | %
Restructuring | 2.1 | % | 2.2 | % | 1.8 | % | (6.2) | % | 28.4 | %
Income from operations | 11.3 | % | 7.7 | % | 10.0 | % | 47.1 | % | (21.7) | %

| Three Months Ended June 30,
| Change
(in thousands) | 2025 (As Restated) | 2024 (As Restated) | 2023 (As Restated) | 2025 vs 2024 (As Restated) | 2024 vs 2023 (As Restated)
Revenue | $ | 2,039,088 |  | $ | 2,041,926 |  | $ | 2,008,201 |  | $ | (2,838) |  | (0.1) | % | $ | 33,725 |  | 1.7 | %
Costs and expenses: |  |  |  |  |  |  |
Direct costs | 1,455,758 |  | 1,488,256 |  | 1,426,406 |  | (32,498) |  | (2.2) | % | 61,850 |  | 4.3 | %
Selling, general and administrative expense | 205,006 |  | 194,458 |  | 187,806 |  | 10,548 |  | 5.4 | % | 6,652 |  | 3.5 | %
Depreciation | 38,661 |  | 33,146 |  | 30,442 |  | 5,515 |  | 16.6 | % | 2,704 |  | 8.9 | %
Amortization | 59,057 |  | 116,489 |  | 114,617 |  | (57,432) |  | (49.3) | % | 1,872 |  | 1.6 | %
Transaction and integration related | 6,717 |  | 6,820 |  | 12,701 |  | (103) |  | (1.5) | % | (5,881) |  | (46.3) | %
Restructuring | 42,950 |  | 45,789 |  | 35,661 |  | (2,839) |  | (6.2) | % | 10,128 |  | 28.4 | %
Income from operations | $ | 230,939 |  | $ | 156,968 |  | $ | 200,568 |  | $ | 73,971 |  | 47.1 | % | $ | (43,600) |  | (21.7) | %

Revenue (as restated)
Revenue for the three months ended June 30, 2025 decreased by $2.8 million, or 0.1%, to $2,039.1 million, compared to $2,041.9 million for the three months ended June 30, 2024; and for the three months ended June 30, 2024 increased by $33.7 million, or 1.7%, to $2,041.9 million compared to $2,008.2 million for the three months ended June 30, 2023. Revenue decreased by 0.9% and increased by 2.0% in constant currency terms for the three months ended June 30, 2025 and June 30, 2024 respectively. Revenue for the three months ended June 30, 2025 was impacted by the volatility and cautiousness present in the broader clinical development market. The increase in revenue for the three months ended June 30, 2024 was due to continued organic growth across the Company's markets.
During the three months ended June 30, 2025, we derived 28.1%, 61.9% and 10.0% of our revenue in the United States, Europe and Rest of World respectively. During the three months ended June 30, 2024, we derived 38.7%, 49.5% and 11.8% of our revenue in the United States, Europe and Rest of World respectively. Revenues from our top five customers amounted to $502.4 million, $509.6 million and $528.2 million in the three months ended June 30, 2025, June 30, 2024 and June 30, 2023 respectively or 24.6%, 25.0% and 26.3% of total revenue respectively. New customer accounts are continually added across the full portfolio of large pharma customers, mid-tier pharma customers and biotech customers.
Revenue in Ireland increased by $274.5 million for the three months ended June 30, 2025, to $902.0 million, compared to $627.5 million for the three months ended June 30, 2024; and increased by $45.1 million for the three months ended June 30, 2024 to $627.5 million, compared to $582.4 million for the three months ended June 30, 2023. Revenue in Ireland during the three months ended June 30, 2025 increased by 43.7% compared to an overall decrease in ICON Group revenue of 0.1% and increased by 7.7% for the three months ended June 30, 2024 compared to an overall increase in Group revenue of 1.7%. Revenue in Ireland is principally a function of our global contracting model.
39

Revenue in our Rest of Europe region during the three months ended June 30, 2025 decreased by $23.1 million or 6.0%, to $360.1 million, compared to $383.2 million for the three months ended June 30, 2024; and increased by $9.7 million or 2.6% for the three months ended June 30, 2024 to $383.2 million, compared to $373.5 million for the three months ended June 30, 2023.
Revenue in the U.S. region during the three months ended June 30, 2025 decreased by $217.1 million or 27.5%, to $573.4 million, compared to $790.5 million for the three months ended June 30, 2024; and decreased by $56.8 million or 6.7%, to $790.5 million for the three months ended June 30, 2024 compared to $847.3 million for the three months ended June 30, 2023.
Revenue in the Rest of World region during the three months ended June 30, 2025 decreased by $37.1 million or 15.4%, to $203.6 million, compared to $240.7 million for the three months ended June 30, 2024; and increased by $35.7 million or 17.4% to $240.7 million for the three months ended June 30, 2024 compared to $205.0 million for the three months ended June 30, 2023.
Direct costs (as restated)
Direct costs for the three months ended June 30, 2025 decreased by $32.5 million, or 2.2%, to $1,455.8 million compared to $1,488.3 million for the three months ended June 30, 2024. The decrease in direct costs arose due to a decrease in personnel related costs, travel and other direct project driven costs, partially offset by increases in third party investigator/other reimbursable costs and laboratory costs. As a percentage of revenue, direct costs have decreased to 71.4% of revenue during the three months ended June 30, 2025 compared to 72.9% for the three months ended June 30, 2024.
Direct costs for the three months ended June 30, 2024 increased by $61.9 million, or 4.3%, to $1,488.3 million compared to $1,426.4 million for the three months ended June 30, 2023. The increase in direct costs arose due to an increase in personnel related costs, third party investigator/other reimbursable costs and other direct project driven costs. As a percentage of revenue, direct costs have increased to 72.9% of revenue during the three months ended June 30, 2024 compared to 71.0% for the three months ended June 30, 2023.
Income from operations (as restated)
Income from operations for the three months ended June 30, 2025 increased by $74.0 million or 47.1% to $230.9 million compared to $157.0 million for the three months ended June 30, 2024. As a percentage of revenue, income from operations increased to 11.3% for the three months ended June 30, 2025 compared to 7.7% of revenue for the three months ended June 30, 2024. Income from operations for the three months ended June 30, 2024 decreased by $43.6 million or 21.7% to $157.0 million compared to $200.6 million for the three months ended June 30, 2023. As a percentage of revenue, income from operations for the three months ended June 30, 2024 decreased to 7.7% compared to 10.0% of revenue for the three months ended June 30, 2023.
Excluding amortization of intangible assets, income from operations in Ireland for the three months ended June 30, 2025 increased to $199.6 million compared to $153.5 million for three months ended June 30, 2024; and decreased to $153.5 million for three months ended June 30, 2024 compared to $231.1 million for the three months ended June 30, 2023. As a percentage of revenue, excluding amortization of intangible assets, income from operations in Ireland for the three months ended June 30, 2025 decreased to 22.1% compared to 24.5% for three months ended June 30, 2024; and decreased to 24.5% for three months ended June 30, 2024 compared to 39.7% for the three months ended June 30, 2023.
In the Rest of Europe region, excluding amortization of intangible assets, income from operations for the three months ended June 30, 2025 decreased to $8.0 million compared to $38.9 million for the three months ended June 30, 2024; and increased to $38.9 million for the three months ended June 30, 2024 compared to $22.4 million for the three months ended June 30, 2023. As a percentage of revenue, excluding amortization of intangible assets, income from operations in the Rest of Europe region for the three months ended June 30, 2025 decreased to 2.2% compared to 10.2% for the three months ended June 30, 2024; and increased to 10.2% for the three months ended June 30, 2024 compared to 6.0% for the three months ended June 30, 2023.
In the U.S. region, income from operations, excluding amortization of intangible assets for the three months ended June 30, 2025 increased to $72.2 million compared to $61.9 million for the three months ended June 30, 2024; and increased to $61.9 million for the three months ended June 30, 2024 compared to $56.3 million for the three months ended June 30, 2023. As a percentage of revenue, excluding amortization of intangible assets, income from operations in the U.S. region for the three months ended June 30, 2025 increased to 12.6% compared to 7.8% for the three months ended June 30, 2024 and increased to 7.8% for the three months ended June 30, 2024 compared to 6.6% for the three months ended June 30, 2023.
In Rest of World, income from operations, excluding amortization of intangible assets for the three months ended June 30, 2025 decreased to $10.2 million compared to $19.2 million for the three months ended June 30, 2024; and increased to $19.2 million for the three months ended June 30, 2024 compared to $5.4 million for the three months ended June 30, 2023. As percentage of revenue, excluding amortization of intangible assets, income from operations in the other regions for the three months ended June 30, 2025 decreased to 5.0% compared to 8.0% for the three months ended June 30, 2024; and increased to 8.0% for the three months ended June 30, 2024 compared to 2.6% for the three months ended June 30, 2023.
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Income tax expense (as restated)

| Three Months Ended June 30,
|  |  |  | Change
(in thousands) | 2025 (As Restated) | 2024 (As Restated) | 2023 (As Restated) | 2025 vs 2024 (As Restated) | 2024 vs 2023 (As Restated)
Income tax (benefit) / expense | $ | (20,674) |  | $ | 14,589 |  | $ | 8,266 |  | $ | (35,263) |  | $ | 6,323 |
Effective income tax rate | (11.3) | % | 15.0 | % | 7.1 | % | (26.3) | % | 7.9 | %

Income tax expense for the three months ended June 30, 2025 changed to a $20.7 million income tax benefit compared to a $14.6 million expense for the three months ended June 30, 2024. The Company’s effective tax rate for the three months ended June 30, 2025 was (11.3)% compared with 15.0% for the three months ended June 30, 2024 primarily due to the net release of provisions for uncertain tax positions in the period ($29.3 million), the release of a deferred tax liability related to investments in foreign subsidiaries associated with unremitted earnings ($30.6 million), partially offset by a reduced level of deferred tax benefit associated with the amortization of intangible assets ($14.6 million).
Income tax expense for the three months ended June 30, 2024 increased to a $14.6 million charge compared to a $8.3 million charge for the three months ended June 30, 2023. The Company’s effective tax rate for the three months ended June 30, 2024 was 15.0% compared with 7.1% for the three months ended June 30, 2023 primarily due to changes in various tax laws.
With the exception of the foregoing, the Company’s effective tax rate remains principally a function of the distribution of pre-tax profits amongst the territories in which it operates.
Three months ended September 30, 2025 compared to three months ended September 30, 2024; and three months ended September 30, 2024 compared to three months ended September 30, 2023.

| Three Months Ended September 30,
| Percentage of Revenue | Percentage Change
| 2025 (As Restated) | 2024 (As Restated) | 2023 (As Restated) | 2025 vs 2024 (As Restated) | 2024 vs 2023 (As Restated)
Revenue | 100.0 | % | 100.0 | % | 100.0 | % | 2.1 | % | 0.1 | %
Costs and expenses: |  |  |  |  |
Direct costs | 73.8 | % | 70.2 | % | 70.9 | % | 7.4 | % | (0.9) | %
Selling, general and administrative expense | 9.5 | % | 10.0 | % | 9.1 | % | (3.9) | % | 10.8 | %
Depreciation | 2.0 | % | 1.8 | % | 1.5 | % | 15.3 | % | 11.3 | %
Amortization | 2.8 | % | 2.8 | % | 5.6 | % | 1.1 | % | (49.4) | %
Transaction and integration related | 0.3 | % | 0.4 | % | 0.5 | % | (10.6) | % | (24.7) | %
Goodwill impairment | 17.5 | % | — | % | — | % | NM | NM
Impairment of non-financial assets | 4.8 | % | — | % | — | % | NM | NM
Income from operations | (10.7) | % | 14.8 | % | 12.4 | % | (173.7) | % | 19.6 | %

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| Three Months Ended September 30,
| Change
(in thousands) | 2025 (As Restated) | 2024 (As Restated) | 2023 (As Restated) | 2025 vs 2024 (As Restated) | 2024 vs 2023 (As Restated)
Revenue | $ | 2,084,415 |  | $ | 2,041,943 |  | $ | 2,040,314 |  | $ | 42,472 |  | 2.1 | % | $ | 1,629 |  | 0.1 | %
Costs and expenses: |  |  |  |  |  |  |
Direct costs | 1,538,951 |  | 1,433,394 |  | 1,445,742 |  | 105,557 |  | 7.4 | % | (12,348) |  | (0.9) | %
Selling, general and administrative expense | 197,049 |  | 205,095 |  | 185,187 |  | (8,046) |  | (3.9) | % | 19,908 |  | 10.8 | %
Depreciation | 40,342 |  | 35,003 |  | 31,459 |  | 5,339 |  | 15.3 | % | 3,544 |  | 11.3 | %
Amortization | 58,688 |  | 58,026 |  | 114,573 |  | 662 |  | 1.1 | % | (56,547) |  | (49.4) | %
Transaction and integration related | 7,020 |  | 7,856 |  | 10,433 |  | (836) |  | (10.6) | % | (2,577) |  | (24.7) | %
Goodwill impairment | 364,248 |  | — |  | — |  | 364,248 |  | NM | — |  | NM
Impairment of non-financial assets | 101,027 |  | — |  | — |  | 101,027 |  | NM | — |  | NM
Income from operations | $ | (222,910) |  | $ | 302,569 |  | $ | 252,920 |  | $ | (525,479) |  | (173.7) | % | $ | 49,649 |  | 19.6 | %

*NM – Not Meaningful
Revenue (as restated)
Revenue for the three months ended September 30, 2025 increased by $42.5 million, or 2.1%, to $2,084.4 million, compared to $2,041.9 million for the three months ended September 30, 2024; and for the three months ended September 30, 2024 increased by $1.6 million, or 0.1%, to $2,041.9 million, compared to $2,040.3 million for the three months ended September 30, 2023. Revenue increased by 0.5% and increased by 0.3% in constant currency terms for the three months ended September 30, 2025 and September 30, 2024 respectively.
During the three months ended September 30, 2025, we derived 31.1%, 57.6% and 11.3% of our revenue in the United States, Europe and Rest of World respectively. During the three months ended September 30, 2024, we derived 37.0%, 51.3% and 11.7% of our revenue in the United States, Europe and Rest of World respectively and for the three months ended September 30, 2023, we derived 40.7%, 47.4% and 11.9% in the United States, Europe and Rest of World respectively. Revenues from our top five customers amounted to $501.3 million, $508.4 million and $515.2 million for the three months ended September 30, 2025, September 30, 2024 and September 30, 2023 respectively, or 24.1%, 24.9% and 25.3% of total revenue respectively. New customer accounts are continually added across the full portfolio of large pharma customers, mid-tier pharma customers and biotech customers.
Revenue in Ireland for the three months ended September 30, 2025 increased by $174.4 million to $801.8 million, compared to $627.4 million for the three months ended September 30, 2024; and increased by $44.6 million for the three months ended September 30, 2024, to $627.4 million, compared to $582.8 million for the three months ended September 30, 2023. Revenue in Ireland for the three months ended September 30, 2025 increased by 27.8% compared to an overall increase in Group revenue of 2.1%; and increased by 7.7% for the three months ended September 30, 2024 compared to an overall increase in Group revenue of 0.1%. Revenue in Ireland is principally a function of our global contracting model.
Revenue in our Rest of Europe region for the three months ended September 30, 2025 decreased by $21.8 million or 5.2%, to $399.0 million, compared to $420.8 million for the three months ended September 30, 2024; and increased by $36.5 million or 9.5% for the three months ended September 30, 2024, to $420.8 million, compared to $384.3 million for the three months ended September 30, 2023.
Revenue in the U.S. region for the three months ended September 30, 2025 decreased by $106.4 million or 14.1%, to $649.0 million, compared to $755.4 million for the three months ended September 30, 2024; and decreased by $75.5 million or 9.1% for the three months ended September 30, 2024, to $755.4 million, compared to $830.9 million for the three months ended September 30, 2023.
Revenue in the Rest of World region for the three months ended September 30, 2025 decreased by $3.7 million or 1.6%, to $234.6 million, compared to $238.3 million for the three months ended September 30, 2024 and decreased by $4.0 million or 1.7% for the three months ended September 30, 2024, to $238.3 million, compared to $242.3 million for the three months ended September 30, 2023.
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Direct costs (as restated)
Direct costs for the three months ended September 30, 2025 increased by $105.6 million or 7.4% to $1,539.0 million compared to $1,433.4 million for the three months ended September 30, 2024. The increase in direct costs arose due to an increase in personnel related costs ($13.7 million of this increase relates to share based compensation expense), third party investigator/other reimbursable costs and laboratory costs partially offset by a decrease in travel and other direct project driven costs. As a percentage of revenue, direct costs have increased to 73.8% of revenue during the three months ended September 30, 2025 compared to 70.2% for the three months ended September 30, 2024.
Direct costs for the three months ended September 30, 2024 decreased by $12.3 million, or 0.9%, to $1,433.4 million compared to $1,445.7 million for the three months ended September 30, 2023. The decrease in direct costs arose due to a decrease in personnel related costs and other direct project driven costs partially offset by increases in third party investigator/other reimbursable costs, laboratories and travel. As a percentage of revenue, direct costs have decreased to 70.2% of revenue during the three months ended September 30, 2024 compared to 70.9% for the three months ended September 30, 2023.
Impairments (as restated)

| Three Months Ended September 30,
|  |  |  | Change
(in thousands) | 2025 (As Restated) | 2024 |  | 2025 vs 2024 (As Restated) |
Goodwill impairment | $ | 364,248 |  | $ | — |  |  | $ | 364,248 |  |
% of revenue | 17.5 | % | — |  |  | NM |
Impairment of non-financial assets | $ | 101,027 |  | $ | — |  |  | $ | 101,027 |  |
% of revenue | 4.8 | % | — |  |  | NM |

The Company recorded a goodwill impairment charge of $364.2 million for the three months ended September 30, 2025 (September 30, 2024: $nil) in the Condensed Consolidated Statements of Operations related to the Data Solutions reporting unit. This represented the entire balance of goodwill attributed to the Data Solutions reporting unit. This charge represents 17.5% of revenue for the three months ended September 30, 2025. Impairment of non-financial assets of $101.0 million (September 30, 2024: $nil) was recorded related to property, plant and equipment and intangible assets in the Data Solutions reporting unit. This charge represents 4.8% of revenue for the three months ended September 30, 2025.
Income from operations (as restated)
Income from operations for the three months ended September 30, 2025 decreased by $525.5 million or 173.7% to $222.9 million loss compared to $302.6 million income for the three months ended September 30, 2024. As a percentage of revenue, income from operations for the three months ended September 30, 2025 decreased to (10.7)% compared to 14.8% of revenue for the three months ended September 30, 2024. Income from operations for the three months ended September 30, 2024 increased by $49.6 million or 19.6% to $302.6 million compared to $252.9 million for the three months ended September 30, 2023. As a percentage of revenue, income from operations for the three months ended September 30, 2024 increased to 14.8% compared to 12.4% of revenue for the three months ended September 30, 2023.
Excluding amortization of intangible assets and the non-cash goodwill and non-financial assets impairment charge, income from operations in Ireland for the three months ended September 30, 2025 decreased to $165.0 million compared to $228.6 million for three months ended September 30, 2024; and increased to $228.6 million for three months ended September 30, 2024 compared to $224.3 million for three months ended September 30, 2023. As a percentage of revenue, excluding amortization of intangible assets and the non-cash goodwill and non-financial assets impairment charge, income from operations in Ireland for the three months ended September 30, 2025 decreased to 20.6% compared to 36.4% for three months ended September 30, 2024; and decreased to 36.4% for three months ended September 30, 2024 compared to 38.5% for three months ended September 30, 2023.
In the Rest of Europe region, excluding amortization of intangible assets and the non-cash goodwill and non-financial assets impairment charge, income from operations for the three months ended September 30, 2025 decreased to $51.0 million compared to $55.2 million for the three months ended September 30, 2024; and decreased to $55.2 million compared to $56.6 million for the three months ended September 30, 2023. As a percentage of revenue, excluding amortization of intangible assets and the non-cash goodwill and non-financial assets impairment charge, income from operations in the Rest of Europe region for the three months ended September 30, 2025 decreased to 12.8% compared to 13.1% for the three months ended September 30, 2024; and decreased to 13.1% for the three months ended September 30, 2024 compared to 14.7% for the three months ended September 30, 2023.
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In the U.S. region, income from operations, excluding amortization of intangible assets and the non-cash goodwill and non-financial assets impairment charge for the three months ended September 30, 2025 increased to $68.2 million compared to $59.6 million for the three months ended September 30, 2024; and decreased to $59.6 million compared to $70.3 million for the three months ended September 30, 2023. As a percentage of revenues, excluding amortization of intangible assets and the non-cash goodwill and non-financial assets impairment charge, income from operations in the U.S. region for the three months ended September 30, 2025 increased to 10.5% compared to 7.9% for the three months ended September 30, 2024; and decreased to 7.9% for the three months ended September 30, 2024 compared to 8.5% for the three months ended September 30, 2023.
In Rest of World, income from operations, excluding amortization of intangible assets and the non-cash goodwill and non-financial assets impairment charge for the three months ended September 30, 2025 decreased to $16.8 million compared to $17.2 million for the three months ended September 30, 2024; and increased to $17.2 million for the three months ended September 30, 2024 compared to $16.3 million for the three months ended September 30, 2023. As percentage of revenue, excluding amortization of intangible assets and the non-cash goodwill and non-financial assets impairment charge, income from operations in the other regions for the three months ended September 30, 2025 and September 30, 2024 remained unchanged at 7.2%; and increased to 7.2% for the three months ended September 30, 2024 compared to 6.7% for the three months ended September 30, 2023.
Income tax expense (as restated)

| Three Months Ended September 30,
|  |  |  | Change
(in thousands) | 2025 (As Restated) | 2024 (As Restated) | 2023 (As Restated) | 2025 vs 2024 (As Restated) | 2024 vs 2023 (As Restated)
Income tax expense | $ | 12,791 |  | $ | 38,432 |  | $ | 16,384 |  | $ | (25,641) |  | $ | 22,048 |
Effective income tax rate | (4.7) | % | 15.3 | % | 9.6 | % | (20.0) | % | 5.7 | %

Income tax expense for the three months ended September 30, 2025 decreased to $12.8 million compared to $38.4 million for the three months ended September 30, 2024. The Company’s effective tax rate for the three months ended September 30, 2025 was (4.7)% compared with 15.3% for the three months ended September 30, 2024. Excluding the non-cash goodwill impairment charge of $364.2 million related to the Company's Data Solutions reporting unit which was recorded in three months ended September 30, 2025, the Company’s effective tax rate for the three months ended September 30, 2025 was 13.8% in comparison with 15.3% for the three months ended September 30, 2024.
Income tax expense for the three months ended September 30, 2024 increased to $38.4 million charge compared to a $16.4 million charge for the three months ended September 30, 2023. The Company’s effective tax rate for the three months ended September 30, 2024 was 15.3% compared with 9.6% for the three months ended September 30, 2023 primarily due to changes in various tax laws.
With the exception of the foregoing, the Company’s effective tax rate remains principally a function of the distribution of pre-tax profits amongst the territories in which it operates.
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Exhibits of ICON plc and subsidiaries

Exhibit Number |  | Title
17.1* |  | List of Subsidiary Guarantors and Issuer of Guaranteed Debt Securities and Affiliates Whose Securities Collateralize Securities of ICON Investments Six Designated Activity Company as at May 27, 2026.
101.1* |  | Interactive Data Files (Inline XBRL – Related Documents).
104 |  | Cover Page Interactive Data File (embedded within the Inline XBRL document and included in Exhibit 101).
* Filed herewith |  |

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SIGNATURES
Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

|  |  | ICON plc
|  |  | /s/ Nigel Clerkin
Date: | May 27, 2026 |  | Nigel Clerkin
|  |  | Chief Financial Officer

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