ACK Asset Management LLC

Q1 2026 13F-HR Holdings

Location
Greenwich, CT
Holdings as of
3/31/2026
Date filed
5/15/2026
Form type
13F-HR
Num holdings
20
Total value ($000)
$801,145
Net value change ($000)
+4,388 (0.6%)
New positions
3
Sold out positions
6
Turnover %
31.5%
Sector allocation + QoQ delta (equities-only)
Prev filing: 2/13/2026 Next filing: — SEC filing

Snapshot: Change Analysis

Compared to Q4 2025
Methodology: sector metrics are equities-only; instrument mix chart is ex-options; options exposure is shown separately. Why this matters.
Top Adds (Value $000, Stocks/ETFs)
LFUS 45,812 NEW
CTS 27,892 NEW
SWIM 27,709 NEW
AERO-SWX 21,279 385.0%
CDNL 14,236 69.7%
ROG 10,993 27.5%
DXPE 9,980 37.9%
MTRN 9,653 16.4%
HLIO 8,756 21.0%
ASTE 8,274 24.3%
Top Reduces (Value $000, Stocks/ETFs)
ENS -44,660 -100.0%
ATRO -32,407 -100.0%
AIN -30,420 -100.0%
APOG -29,601 -100.0%
GVA -27,705 -48.0%
ERII -9,136 -100.0%
CTOS -4,609 -100.0%
JHX -3,801 -8.7%
WMS -3,003 -5.3%
EXP -2,843 -8.3%
Instrument mix + QoQ Δ (ex-options)
How this table is calculated: SEC VALUE ($000) is used as reported. For derivatives (PUT/CALL/WARRANT/RIGHT), SEC value represents reported underlying exposure, not premium cash paid/received. Column % is bucket-based: non-options share is calculated inside non-option total, options share is calculated inside options total. Details.
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Instrument:
Issuer Name Ticker Sector Industry Class History Value ($000) % Shares Shares Δ Shares Δ% Value Δ ($000) Value Δ% Principal Option Type