WILLIAM BLAIR INVESTMENT MANAGEMENT, LLC

Position in CWST — Casella Waste Systems Inc

CIK 1644956 CHICAGO, IL

Position in CWST

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

Position Value

$99,737,679

-$44,058,416 QoQ

Shares Held

1,257,092

-14.4% QoQ

Ownership

1.98%

of shares outstanding

% of Portfolio

0.33%

of 13F equity value

Holder Rank

—

not a current holder

Holding Since

Mar 2020

25 quarters on record

Voting authority Sole 91.65908302654063.ToString("F0")% Shared 0.ToString("F0")% None 8.34091697345938.ToString("F0")%

Industrials · as of Mar 31, 2026

WILLIAM BLAIR INVESTMENT MANAGEMENT, LLC holds $226,787,168 across 2 Waste Management names. CWST ranks #2 (44.0% of the industry book) .

#	Ticker	Company	Shares	Value (USD)	Open
1	CLH	Clean Harbors Inc	443,098	$127,049,489
2	CWST	Casella Waste Systems Inc This page	1,257,092	$99,737,679

25 filing rows on record

Report Date	Value (USD)	Shares	Change	Type	Discretion	Filed
2026-03-31	$99,737,679	1,257,092	-14.4%	Shares	Sole	2026-05-08
2025-12-31	$143,796,095	1,468,206	-18.9%	Shares	Sole	2026-02-09
2025-09-30	$171,720,180	1,809,867	+0.5%	Shares	Sole	2025-11-12
2025-06-30	$207,701,883	1,800,155	-18.8%	Shares	Sole	2025-07-29
2025-03-31	$247,135,710	2,216,265	-16.1%	Shares	Sole	2025-05-09
2024-12-31	$279,391,093	2,640,498	-0.4%	Shares	Sole	2025-02-10
2024-09-30	$263,858,622	2,652,112	-0.5%	Shares	Sole	2024-11-08
2024-06-30	$264,594,835	2,666,749	-0.1%	Shares	Sole	2024-08-08
2024-03-31	$263,960,159	2,669,770	-7.9%	Shares	Sole	2024-05-08
2023-12-31	$247,843,400	2,900,110	-4.8%	Shares	Sole	2024-02-09
2023-09-30	$232,506,319	3,047,265	+1.8%	Shares	Sole	2023-11-09
2023-06-30	$270,644,399	2,992,199	+1.8%	Shares	Sole	2023-08-11
2023-03-31	$242,845,408	2,937,883	+20.4%	Shares	Sole	2023-05-12
2022-12-31	$193,481,900	2,439,565	-2.2%	Shares	Sole	2023-02-09
2022-09-30	$190,487,249	2,493,615	+19.2%	Shares	Sole	2022-11-09
2022-06-30	$152,085,516	2,092,536	+0.9%	Shares	Sole	2022-08-10
2022-03-31	$181,787,590	2,074,017	+232.6%	Shares	Sole	2022-05-11
2021-12-31	$53,271,926	623,647	-20.7%	Shares	Sole	2022-02-14
2021-09-30	$59,721,342	786,428	+1.1%	Shares	Sole	2021-11-10
2021-06-30	$49,333,824	777,768	-2.3%	Shares	Sole	2021-08-12
2021-03-31	$50,589,450	795,807	+8.9%	Shares	Sole	2021-05-13
2020-12-31	$45,284,706	730,988	+16.0%	Shares	Sole	2021-02-09
2020-09-30	$35,191,085	630,100	+19.0%	Shares	Sole	2020-11-06
2020-06-30	$27,597,018	529,490	-12.8%	Shares	Sole	2020-08-12
2020-03-31	$23,719,106	607,248	—	Shares	Sole	2020-05-08
No filing history on record for this holder in this stock.