ACK Asset Management LLC
Filing Date
Global Rank
#2,034
/ 8,603
▲ 41
· as of Mar 2026
Top Industry
Industrial Distribution
16.1%
3Y Alpha vs SPY
-3.6%
Period ended 3 months ago
Filed May 15, 2026 · 55d
25 quarters · since Mar 2020
Clone Performance
Jul 2023–Jul 2026 · vs SPYHypothetical growth of cloning every reported 13F position and rebalancing on each filing, indexed to the same start.
Cloned portfolio
+56.9%
SPY
+76.0%
Annualised alpha
-4.5%
Max drawdown
−34.6%
Estimate. 13F holdings are quarter-lagged and long-only, so the clone rebalances about 45 days after each period end — when the filing becomes public — and excludes options and short positions. Past performance does not predict future results.
Portfolio Concentration
19 positions · as of Mar 31, 2026 · Δ vs Dec 31, 2025Top Position
8.9%
+1.3 pts
Top 5
35.6%
+1.1 pts
Top 10
64.1%
+2.1 pts
HHI
568
Diversified+37
Portfolio Trend
25 quarters · across all stocks
Sector Breakdown
As of Mar 31, 2026| Sector | % Portfolio | Value |
|---|---|---|
| Industrials | 53.7% | $415,440,617 |
| Technology | 24.3% | $188,437,834 |
| Basic Materials | 18.0% | $139,713,070 |
| Consumer Cyclical | 4.0% | $30,747,000 |
Last Quarter's Activity
Export CSVAdded To
Positions the filer increased
5 positions
| Ticker | Company | Δ Shares | Shares | Value | Open |
|---|---|---|---|---|---|
| MBC | MasterBrand, Inc. | +1,400,000 | 3,700,000 | $30,747,000 | |
| CLFD | Clearfield, Inc. | +110,000 | 735,200 | $19,460,744 | |
| ROG | Rogers Corp | +38,293 | 475,000 | $50,981,750 | |
| CDNL | Cardinal Infrastructure Group Inc. | +29,409 | 874,000 | $34,658,470 | |
| DXPE | Dxp Enterprises Inc | +20,000 | 260,000 | $36,329,800 | |
| No positions match the current search. | |||||
Trimmed
Positions the filer reduced
1 positions
| Ticker | Company | Δ Shares | Shares | Value | Open |
|---|---|---|---|---|---|
| GVA | Granite Construction Inc | −250,000 | 250,000 | $29,970,000 | |
| No positions match the current search. | |||||
Sold Out
Positions the filer fully exited
6 positions
| Ticker | Company | Shares | Value | Open |
|---|---|---|---|---|
| ENS | EnerSys | 304,324 | $44,659,547 | |
| AIN | Albany International Corp /De/ | 600,000 | $30,420,000 | |
| APOG | Apogee Enterprises, Inc. | 813,000 | $29,601,330 | |
| ATRO | Astronics Corp | 597,469 | $25,863,297 | |
| ERII | Energy Recovery, Inc. | 677,251 | $9,136,115 | |
| CTOS | Custom Truck One Source, Inc. | 800,136 | $4,608,783 | |
| No positions match the current search. | ||||
19 positions ·
$774,338,521 total
· as of Mar 31, 2026
| Ticker | Company | Type | Shares | Value (USD) | % of Portfolio | History |
|---|---|---|---|---|---|---|
| MTRN |
MATERION Corp
Basic Materials
|
Held | 474,800 | $68,679,820 | 8.87% | |
| WMS |
Advanced Drainage Systems, Inc.
Industrials
|
Held | 390,000 | $53,480,700 | 6.91% | |
| ATS |
ATS Corp /ATS
Industrials
|
Held | 1,846,196 | $52,062,727 | 6.72% | |
| ROG |
Rogers Corp
Technology
|
Added | 475,000 | $50,981,750 | 6.58% | |
| HLIO |
Helios Technologies, Inc.
Industrials
|
Held | 780,378 | $50,498,260 | 6.52% | |
| LFUS |
Littelfuse Inc /De
Technology
|
NEW | 135,000 | $45,812,250 | 5.92% | |
| CNM |
Core & Main, Inc.
Industrials
|
Held | 900,000 | $44,460,000 | 5.74% | |
| NOVT |
Novanta Inc
Technology
|
Held | 375,000 | $44,291,250 | 5.72% | |
| SITE |
SiteOne Landscape Supply, Inc.
Industrials
|
Held | 330,000 | $43,926,300 | 5.67% | |
| ASTE |
Astec Industries Inc
Industrials
|
Held | 786,500 | $42,345,160 | 5.47% | |
| JHX |
James Hardie Industries plc
Basic Materials
|
Held | 2,100,000 | $39,774,000 | 5.14% | |
| DXPE |
Dxp Enterprises Inc
Industrials
|
Added | 260,000 | $36,329,800 | 4.69% | |
| CDNL |
Cardinal Infrastructure Group Inc.
Industrials
|
Added | 874,000 | $34,658,470 | 4.48% | |
| EXP |
Eagle Materials Inc
Basic Materials
|
Held | 165,000 | $31,259,250 | 4.04% | |
| MBC |
MasterBrand, Inc.
Consumer Cyclical
|
Added | 3,700,000 | $30,747,000 | 3.97% | |
| GVA |
Granite Construction Inc
Industrials
|
Reduced | 250,000 | $29,970,000 | 3.87% | |
| CTS |
Cts Corp
Technology
|
NEW | 584,000 | $27,891,840 | 3.60% | |
| SWIM |
Latham Group, Inc.
Industrials
|
NEW | 5,160,000 | $27,709,200 | 3.58% | |
| CLFD |
Clearfield, Inc.
Technology
|
Added | 735,200 | $19,460,744 | 2.51% |