SEC ownership of ICON PLC

Top holders, 13D/G large-stake signals, insider positions, and transaction flow tied to CIK 0001060955.

Comparable stake leader

Artisan Partners Limited Partnership

Disclosed value leader

Artisan Partners Limited Partnership

Comparable rows

50/50

Latest evidence

31 Mar 2026

Top shareholders Insider holders Latest transactions

Public ticker: ICLR on Nasdaq
Parsed ownership sources: 13F, 13D/G, and 3/4/5
Source: Parsed SEC ownership filingsUse: Compare filing families carefully
Largest SEC-reported holder: Artisan Partners Limited Partnership
Ranking: Comparable ownership first, then disclosed value
Comparable ownership rows: 50 of 50
Meaning: Rows with safely comparable ownership %
Latest 13D/G holder: Artisan Partners Limited Partnership
Source: Latest parsed Schedule 13D/G stake
Latest parsed ownership date: 31 Mar 2026
Freshness: Most recent filing date in this holder set
Issuer CIK: 0001060955
Issuer location: Dublin 18, Ireland

Ownership snapshot

Top shareholders of ICON PLC (13F + 13D/G + 3/4/5)

Grouped by holder across the latest SEC ownership disclosures. Start with comparable ownership when available, then verify the linked 13F, 13D/G, or 3/4/5 evidence.

Comparable stake leader

Artisan Partners Limited ...

Disclosed value leader

Artisan Partners Limited ...

Comparable rows

50/50

Latest evidence

31 Mar 2026

13F 13D/G 3/4/5 Lead comparable stake: 11% 13D/G row: Artisan Partners Limited Partnership Showing 1-8 of 50 holder rows.

Quick read

Artisan Partners Limited Partnership leads the comparable SEC ownership view at 11%.

50 of 50 rows have a safely comparable ownership percentage. Use this as a filing-backed starting point, then open the detailed table for source links, reporting role, position value, share count, and filing date.

Open SEC evidence Opens Artisan Partners Limited Partnership's linked filing trail.

Comparable ownership Top 5

Artisan Partners Limited Partnership 11%

WELLINGTON MANAGEMENT GROUP LLP 7.7%

HARRIS ASSOCIATES L P 5.7%

FMR LLC 5.5%

Invesco Ltd. 5.1%

Ownership % is shown only when SEC disclosures are safely comparable across share classes.

Detailed SEC evidence table Showing 1-8 of 50 holder rows

Holder	Evidence	Ownership %	Position	12M Net Δ	As of
Artisan Partners Limited Partnership	13F 13D/G Company · Artisan Partners Asset Management Inc. 13F 13D/G	11% from 13D/G	$916,148,054 8,278,945 shares	—	31 Mar 2026
WELLINGTON MANAGEMENT GROUP LLP	13F 13D/G Company 13F 13D/G	7.7% from 13D/G	$654,336,675 5,913,037 shares	—	31 Mar 2026
HARRIS ASSOCIATES L P	13F 13D/G Company 13F 13D/G	5.7% from 13D/G	$481,516,739 4,351,317 shares	—	31 Mar 2026
FMR LLC	13F 13D/G Company 13F 13D/G	5.5% from 13D/G	$461,895,449 4,174,006 shares	—	31 Mar 2026
Invesco Ltd.	13F 13D/G Company 13F 13D/G	5.1% from 13D/G	$429,235,666 3,878,869 shares	—	31 Mar 2026
WCM INVESTMENT MANAGEMENT, LLC	13D/G 13D/G	0.25%	$26,956,720 199,946 shares	$0	30 Jun 2025
Stephen A. Cutler	3/4/5 Director 3/4/5	0.1%	$8,252,047 79,278 shares	—	18 Mar 2026
Ciaran Murray	3/4/5 Director 3/4/5	0.03%	$2,128,848 20,452 shares	—	18 Mar 2026

How to read this table

Rows are grouped by holder and ranked first by SEC-reported ownership % when it is safely comparable, then by disclosed holdings value. — indicates unavailable or non-comparable values; "mixed-class rows" means the latest filing spans non-comparable classes.

Forms 3/4/5 flow

Insider trading overview

Insider buy and sell flow is broadly balanced over the last 12 months. No Buy or Sell transactions have been reported since 21 Jun 2025.

Buys

Insiders: 0

Sells

Insiders: 0

Net

Shares: 0

Window

Last 12 months

4 rolling buckets

Buy value Sell value

Shares: 0 Shares: 0

Window (months)	Buy value	Sell value	Net value
0-3	$0	$0	$0
3-6	$0	$0	$0
6-9	$0	$0	$0
9-12	$0	$0	$0

Reporting owners

Insider holders from Forms 3/4/5

Showing 1-13 of 13 reporting-owner rows connected to ICON PLC. Open a relationship link for the CIK-to-CIK filing trail.

Rows

Largest Forms 3/4/5 holder

John Dr Climax

Net 12M change

Latest report

01 Jun 2026

Name	Relationship	Holdings Value	Valuation	Report Date
John Dr Climax	Director	$29,942,215	Mixed	14 May 2026
Stephen A. Cutler	Director	$8,252,047	Mixed	18 Mar 2026
Ciaran Murray	Director	$2,128,848	Mixed	18 Mar 2026
Linda S. Grais	Director	$548,658	Mixed	18 Mar 2026
Barry Edward Balfe	Chief Executive Officer, Director	$464,033	Mixed	18 Mar 2026
Nigel Bernard John Clerkin	Chief Financial Officer	$401,266	Mixed	18 Mar 2026
Ronan Martin Murphy	Director	$307,690	Mixed	14 May 2026
Eugene Pacelli McCague	Director	$303,942	Mixed	14 May 2026
Julie O'Neill	Director	$280,834	Mixed	18 Mar 2026
Emer Lyons	Chief Accounting Officer	$78,275	Mixed	18 Mar 2026
Anne Clem Whitaker	Director		Mixed	18 Mar 2026
Jeffrey Thomas Elliott	Director		Mixed	01 Jun 2026
Kevin Francis Egan	Director		Mixed	01 Jun 2026

Recent insider transactions for ICON PLC

Showing up to 300 recent insider transactions from the last 12 months.

Insider	Symbol	Class	Transaction	%	Shares	Shares owned	Date	Ownership
Ronan Martin Murphy	ICLR	Stock Options	Award		5,005	5,005	14 May 2026	Direct
Ronan Martin Murphy	ICLR	Stock Options	Disposed to Issuer	-100%	-5,005	0	14 May 2026	Direct
John Dr Climax	ICLR	Stock Options	Award		5,005	5,005	14 May 2026	Direct
John Dr Climax	ICLR	Stock Options	Disposed to Issuer	-100%	-5,005	0	14 May 2026	Direct
Eugene Pacelli McCague	ICLR	Stock Options	Award		3,255	3,255	14 May 2026	Direct
Eugene Pacelli McCague	ICLR	Stock Options	Disposed to Issuer	-100%	-3,255	0	14 May 2026	Direct

^* marks a reported price that did not pass the local price check.