ACK Asset Management LLC — 13F Holdings

2026 Q1  ·  26 Positions

2026 Q1 Portfolio Activity

In 2026 Q1, ACK Asset Management LLC maintained a portfolio of 26 distinct positions. The most significant new addition was LFUS, now representing 5.72% of the total fund value. They heavily accumulated shares in JHX, increasing the position by 1256.1%. Conversely, ACK Asset Management LLC completely exited their position in ENS.
Position History hover any row below to update
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PCA Score Concentration Risk
Risk ENB
Total Positions
26
Quarter
2026 Q1
Top Holding
MTRN (8.6%)
Top 10 Concentration
62.0%
Turnover Rate
23.4%
Sector HHI
0.18
Items per page:
Showing 1-26 of 26

ACK Asset Management LLC Full Holdings List — 2026 Q1

Stock History Sector / Type Port % Prev % Rank / Prev Conviction
Freshness
Change % Change Influence Shares Mkt Value Avg Cost Price Held 1st Owned Source Source Date Date Reported
MTRN
MTRN
Basic Materials 8.57% 7.41% #1
Prev: #1
6.4
no change no change
P
S
474,800 $68,679,820
$85.97 -12.6%
$72.35 +3.9%
2012 Q1 13F Filing 2026-03-31 2026-05-15
WMS
WMS
Industrials 6.68% 7.09% #2 1
Prev: #3
5.2
no change no change
P
S
390,000 $53,480,700
$24.40 +439.4%
$137.13 -4.0%
2014 Q3 13F Filing 2026-03-31 2026-05-15
ATS
ATS
Industrials 6.50% 6.38% #3 1
Prev: #4
4.6
no change no change
P
S
1,846,196 $52,062,727
$32.72 -2.4%
$28.20 +13.3%
2022 Q4 13F Filing 2026-03-31 2026-05-15
ROG
ROG
Technology 6.36% 5.02% #4 7
Prev: #11
5.0
38,293 8.8%
P
S
475,000 $50,981,750 2010 Q4 13F Filing 2026-03-31 2026-05-15
HLIO
HLIO
Industrials 6.30% 5.24% #5 4
Prev: #9
4.0
no change no change
P
S
780,378 $50,498,260 2020 Q2 13F Filing 2026-03-31 2026-05-15
LFUS
LFUS
Technology 5.72% #6
Prev: #—
5.8
135,000
NEW
135,000 $45,812,250 2026 Q1 13F Filing 2026-03-31 2026-05-15
CNM
CNM
Industrials 5.55% 5.87% #7 2
Prev: #5
3.2
no change no change
P
S
900,000 $44,460,000 2023 Q1 13F Filing 2026-03-31 2026-05-15
NOVT
NOVT
Technology 5.53% 5.60% #8 1
Prev: #7
3.2
no change no change
P
S
375,000 $44,291,250 2025 Q4 13F Filing 2026-03-31 2026-05-15
SITE
SITE
Industrials 5.48% 5.16% #9 1
Prev: #10
3.2
no change no change
P
S
330,000 $43,926,300 2025 Q1 13F Filing 2026-03-31 2026-05-15
ASTE
ASTE
Industrials 5.29% 4.28% #10 3
Prev: #13
3.1
no change no change
P
S
786,500 $42,345,160 2014 Q2 13F Filing 2026-03-31 2026-05-15
N/A
JHX
Unknown 4.96% 5.47% #11 3
Prev: #8
3.0
no change no change
P
S
2,100,000 $39,774,000 13F Filing 2026-03-31 2026-05-15
DXPE
DXPE
Industrials 4.53% 3.31% #12 5
Prev: #17
3.8
20,000 8.3%
P
S
260,000 $36,329,800 2025 Q2 13F Filing 2026-03-31 2026-05-15
CDNL
CDNL
Industrials 4.33% 2.56% #13 6
Prev: #19
2.2
29,409 3.5%
P
S
874,000 $34,658,470 2025 Q4 13F Filing 2026-03-31 2026-05-15
EXP
EXP
Basic Materials 3.90% 4.28% #14 2
Prev: #12
2.6
no change no change
P
S
165,000 $31,259,250 2015 Q2 13F Filing 2026-03-31 2026-05-15
MBC
MBC
Consumer Cyclical 3.84% 3.19% #15 3
Prev: #18
4.5
1,400,000 60.9%
P
S
3,700,000 $30,747,000 2024 Q3 13F Filing 2026-03-31 2026-05-15
GVA
GVA
Industrials 3.74% 7.24% #16 14
Prev: #2
1.5
-250,000 -50.0%
P
S
250,000 $29,970,000 2011 Q4 13F Filing 2026-03-31 2026-05-15
CTS
CTS
Technology 3.48% #17
Prev: #—
4.9
584,000
NEW
584,000 $27,891,840 2022 Q4 13F Filing 2026-03-31 2026-05-15
SWIM
SWIM
Industrials 3.46% #18
Prev: #—
4.9
5,160,000
NEW
5,160,000 $27,709,200 2021 Q4 13F Filing 2026-03-31 2026-05-15
N/A
AERO-SWX
Unknown 3.35% 0.69% #19 3
Prev: #22
4.3
675,149 436.0%
P
S
830,000 $26,806,307 13F Filing 2026-03-31 2026-05-15
CLFD
CLFD
Technology 2.43% 2.29% #20
Prev: #20
3.0
110,000 17.6%
P
S
735,200 $19,460,744 2023 Q4 13F Filing 2026-03-31 2026-05-15
CTOS
CTOS
Industrials 0.00% 0.58%
Sold All 😨
(Was: #23)
0.0
-800,136 -100.0%
CLOSED
$— 2025 Q2 13F Filing 2026-03-31 2026-05-15
ERII
ERII
Industrials 0.00% 1.15%
Sold All 😨
(Was: #21)
0.0
-677,251 -100.0%
CLOSED
$— 2022 Q2 13F Filing 2026-03-31 2026-05-15
APOG
APOG
Industrials 0.00% 3.72%
Sold All 😨
(Was: #16)
0.0
-813,000 -100.0%
CLOSED
$— 2025 Q3 13F Filing 2026-03-31 2026-05-15
AIN
AIN
Consumer Cyclical 0.00% 3.82%
Sold All 😨
(Was: #15)
0.0
-600,000 -100.0%
CLOSED
$— 2025 Q2 13F Filing 2026-03-31 2026-05-15
ATRO
ATRO
Industrials 0.00% 4.07%
Sold All 😨
(Was: #14)
0.0
-597,469 -100.0%
CLOSED
$— 2013 Q3 13F Filing 2026-03-31 2026-05-15
ENS
ENS
Industrials 0.00% 5.61%
Sold All 😨
(Was: #6)
0.0
-304,324 -100.0%
CLOSED
$— 2011 Q4 13F Filing 2026-03-31 2026-05-15
Showing 1-26 of 26 holdings

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