WILLIAM BLAIR INVESTMENT MANAGEMENT, LLC

Position in ECVT — Ecovyst Inc.

CIK 1644956 CHICAGO, IL

Position in ECVT

as of Mar 31, 2026 · filed May 8, 2026 Compact

Position Value

$23,979,026

-$2,571,701 QoQ

Shares Held

1,864,621

-31.7% QoQ

Ownership

1.70%

of shares outstanding

% of Portfolio

0.08%

of 13F equity value

Holder Rank

—

not a current holder

Holding Since

Jun 2023

12 quarters on record

Voting authority Sole 69.33543063174768.ToString("F0")% Shared 0.ToString("F0")% None 30.664569368252316.ToString("F0")%

Basic Materials · as of Mar 31, 2026

WILLIAM BLAIR INVESTMENT MANAGEMENT, LLC holds $467,045,561 across 6 Specialty Chemicals names. ECVT ranks #5 (5.1% of the industry book) .

#	Ticker	Company	Shares	Value (USD)
1	LIN	Linde PLC	636,338	$315,470,926
2	BCPC	Balchem Corp	315,260	$53,430,264
3	KWR	Quaker Chemical Corp	388,406	$48,251,677
4	HWKN	Hawkins Inc	165,269	$25,385,318
5	ECVT	Ecovyst Inc. This page	1,864,621	$23,979,026
6	ESI	Element Solutions Inc	15,476	$528,350

12 filing rows on record

Report Date	Value (USD)	Shares	Change	Type	Discretion	Filed
2026-03-31	$23,979,026	1,864,621	-31.7%	Shares	Sole	2026-05-08
2025-12-31	$26,550,727	2,728,749	-9.5%	Shares	Sole	2026-02-09
2025-09-30	$26,404,041	3,014,160	-5.7%	Shares	Sole	2025-11-12
2025-06-30	$26,310,503	3,196,902	-7.6%	Shares	Sole	2025-07-29
2025-03-31	$21,460,159	3,461,316	-3.9%	Shares	Sole	2025-05-09
2024-12-31	$27,514,283	3,601,346	+1.9%	Shares	Sole	2025-02-10
2024-09-30	$24,207,954	3,534,008	-3.0%	Shares	Sole	2024-11-08
2024-06-30	$32,674,776	3,642,673	-0.2%	Shares	Sole	2024-08-08
2024-03-31	$40,702,004	3,650,404	+10.1%	Shares	Sole	2024-05-08
2023-12-31	$32,401,228	3,316,400	-1.6%	Shares	Sole	2024-02-09
2023-09-30	$33,166,792	3,370,609	+4.0%	Shares	Sole	2023-11-09
2023-06-30	$37,134,972	3,240,399	—	Shares	Sole	2023-08-11
No filing history on record for this holder in this stock.