WILLIAM BLAIR INVESTMENT MANAGEMENT, LLC

Position in OC — Owens Corning

CIK 1644956 CHICAGO, IL

Position in OC

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

Position Value

$11,305,959

-$7,451,611 QoQ

Shares Held

104,472

-37.7% QoQ

Ownership

0.130%

of shares outstanding

% of Portfolio

0.04%

of 13F equity value

Holder Rank

—

not a current holder

Holding Since

Dec 2020

17 quarters on record

Voting authority Sole 82.97055670418868.ToString("F0")% Shared 0.ToString("F0")% None 17.029443295811316.ToString("F0")%

Industrials · as of Mar 31, 2026

WILLIAM BLAIR INVESTMENT MANAGEMENT, LLC holds $182,215,227 across 5 Building Products & Equipment names. OC ranks #5 (6.2% of the industry book) .

#	Ticker	Company	Shares	Value (USD)
1	WMS	Advanced Drainage Systems, Inc.	655,684	$89,913,946
2	LPX	Louisiana-Pacific Corp	596,108	$43,366,857
3	TREX	Trex Co Inc	647,178	$23,570,222
4	JBI	Janus International Group, Inc.	2,729,756	$14,058,243
5	OC	Owens Corning This page	104,472	$11,305,959

17 filing rows on record

Report Date	Value (USD)	Shares	Change	Type	Discretion	Filed
2026-03-31	$11,305,959	104,472	-37.7%	Shares	Sole	2026-05-08
2025-12-31	$18,757,570	167,613	-6.5%	Shares	Sole	2026-02-09
2025-09-30	$25,362,080	179,288	+0.1%	Shares	Sole	2025-11-12
2025-06-30	$24,621,993	179,043	+0.4%	Shares	Sole	2025-07-29
2025-03-31	$25,459,664	178,264	-2.5%	Shares	Sole	2025-05-09
2024-12-31	$31,135,177	182,804	-0.3%	Shares	Sole	2025-02-10
2024-09-30	$32,363,706	183,343	+0.1%	Shares	Sole	2024-11-08
2024-06-30	$31,817,860	183,156	+2088.8%	Shares	Sole	2024-08-08
2022-12-31	$713,790	8,368	-18.0%	Shares	Sole	2023-02-09
2022-09-30	$801,822	10,200	-94.8%	Shares	Sole	2022-11-09
2022-06-30	$14,671,617	197,438	-9.7%	Shares	Sole	2022-08-10
2022-03-31	$20,012,056	218,711	-21.7%	Shares	Sole	2022-05-11
2021-12-31	$25,286,786	279,412	-17.3%	Shares	Sole	2022-02-14
2021-09-30	$28,892,074	337,919	+0.9%	Shares	Sole	2021-11-10
2021-06-30	$32,776,528	334,796	+37.0%	Shares	Sole	2021-08-12
2021-03-31	$22,497,771	244,302	+10.4%	Shares	Sole	2021-05-13
2020-12-31	$16,769,930	221,356	—	Shares	Sole	2021-02-09
No filing history on record for this holder in this stock.