Port Capital LLC

Position in ATMU — Atmus Filtration Technologies Inc.

CIK 1729212 CHICAGO, IL

Position in ATMU

as of Jun 30, 2026 · filed Aug 14, 2026 Compact

Position Value

$52,738,600

+$1,152,837 QoQ

Shares Held

1,034,293

+13.8% QoQ

Ownership

1.27%

of shares outstanding

% of Portfolio

2.07%

of 13F equity value

Holder Rank

#21

of 333 holders

Holding Since

Sep 2025

4 quarters on record

Voting authority Sole 100% Shared 0% None 0%

Consumer Cyclical · as of Jun 30, 2026

Port Capital LLC holds $138,277,911 across 3 Auto Parts names. ATMU ranks #2 (38.1% of the industry book) .

#	Ticker	Company	Shares	Value (USD)
1	ORLY	O Reilly Automotive Inc	928,311	$85,488,159
2	ATMU	Atmus Filtration Technologies Inc. This page	1,034,293	$52,738,600
3	SLDP	Solid Power, Inc.	19,750	$51,152

4 filing rows on record

Report Date	Value (USD)	Shares	Change	Type	Discretion	Filed
2026-06-30	$52,738,600	1,034,293	+13.8%	Shares	Sole	2026-08-14
2026-03-31	$51,585,763	908,680	+3.6%	Shares	Sole	2026-05-15
2025-12-31	$45,510,535	876,720	+103.7%	Shares	Sole	2026-02-17
2025-09-30	$19,409,441	430,460	—	Shares	Sole	2025-11-14
No filing history on record for this holder in this stock.