13F Insight
DOSSIER · 13F-HR · Q2 2026

ACK Asset Management LLC

$856M in tracked AUM across 21 positions as of Q2 2026.

AA
CIK 0001510940 · last filed Jun 30, 2026
Total AUM
$856M
as of Q2 2026
Holdings
21
—
positions
Whale Score
68
68
tracked
Activity
—
no data
changes this Q
AI Analysis · Q2 2026

ACK Asset Management LLC filed its latest 13F-HR for Q2 2026. See the latest holdings and position changes below.

Quarter at a glance — Q2 2026

Position-change comparison pending.

No quarter-over-quarter changes available.

Top 10 holdings

By portfolio weight as of Q2 2026.

#HoldingValueSharesWeight
01
WMS
WMS
$61M390K7.1%02
HLIO
HLIO
$61M681K7.1%03
LFUS
LFUS
$57M125K6.6%04
G4253H101
JHX
$55M2.1M6.4%05
GTX
GTX
$54M1.5M6.3%06
CNM
CNM
$53M1.1M6.1%07
EXP
EXP
$50M220K5.8%08
ATS
ATS
$43M1.5M5.0%09
ASTE
ASTE
$42M690K4.9%10
MTRN
MTRN
$40M135K4.7%

Filing history

2026Q2Jun 30
$856M▲ 6.9%
21 positionsView →2026Q1Mar 31
$801M▲ 0.6%
20 positionsView →2025Q4Dec 31
$797M▼ 0.3%
23 positionsView →2025Q3Sep 30
$799M▲ 5.0%
20 positionsView →2025Q2Jun 30
$761M▲ 25.0%
21 positionsLocked2025Q1Mar 31
$609M▼ 18.4%
20 positionsLocked2024Q4Dec 31
$746M▼ 7.8%
22 positionsLocked2024Q3Sep 30
$809M▼ 0.1%
18 positionsLocked2024Q2Jun 30
$810M▼ 5.6%
19 positionsLocked2024Q1Mar 31
$858M▲ 3.2%
20 positionsLocked2023Q4Dec 31
$831M▲ 20.8%
21 positionsLocked2023Q3Sep 30
$688M▼ 14.3%
21 positionsLocked
Showing 12 of 61