ACK Asset Management LLC
Regulatory profile
From Form ADV, the SEC filer profile, 13D/13G type codes and N-CEN, never from the name.
Portfolio style
Measured from the filed 13F common-share book for Jun 30, 2026, never from the firm's own description.
Closest benchmark: the S&P MidCap 400 as of 2026-06-30, active share 98.4%; sector active share 61.3% against the combined 13F book's sector weights.
Over time 26 measured quarters
How the bands are measured
Style bands measure the filed 13F common-share book each closed quarter, tested in this order. Unknown: under $10,000,000 of valued equity or 5 stocks. Index-like (100+ stocks): active share of 20% or less against the closest benchmark, which is the S&P 500, S&P MidCap 400, S&P SmallCap 600, Russell 1000, Russell 2000, Nasdaq-100 or Dow Jones Industrial Average (weighted by an index-tracking fund's reported holdings or the index's constituents nearest the quarter end, over the names resolved to companies, and only when those are 90%+ of its weight) or every 13F filer's combined book, or index series holding 80%+ of the registered fund assets it advises (N-CEN) and equal to 50%+ of its book. Systematic-like: 500+ stocks, 100%+ annual turnover and a top 10 weight of 25% or less. Concentrated: a top 10 weight of 60%+ or 12 or fewer effective positions. Diversified active: none of these. Turnover is the smaller of buys and sells over average equity value, summed over four quarters: low under 30%, high 100%+. Horizon is the value-weighted number of quarters each position has been held: short under 4, long 12+.
Clone Performance
Build a hypothetical price-return history from this filer's public 13F holdings.
View clone backtestPortfolio Concentration
20 tracked positions · as of Jun 30, 2026 · Δ vs Mar 31, 2026Portfolio Trend
Sector Breakdown
As of Jun 30, 2026| Sector | % Portfolio | Value |
|---|---|---|
| Industrials | 47.6% | $394,214,195 |
| Technology | 18.9% | $156,768,783 |
| Basic Materials | 17.5% | $144,625,650 |
| Consumer Cyclical | 16.0% | $132,258,000 |
Last Quarter's Activity
Export CSVAdded To
Positions the filer increasedTrimmed
Positions the filer reduced| Ticker | Company | Δ Shares | Shares | Value | Open |
|---|---|---|---|---|---|
| ATS | ATS Corp | −346,196 | 1,500,000 | $43,170,000 | |
| MTRN | MATERION Corp | −339,800 | 135,000 | $40,147,650 | |
| HLIO | Helios Technologies, Inc. | −99,378 | 681,000 | $60,779,250 | |
| ASTE | Astec Industries Inc | −96,224 | 690,276 | $42,237,988 | |
| LFUS | Littelfuse Inc | −10,000 | 125,000 | $56,916,250 | |
| No positions match the current search. | |||||
New Positions
Positions the filer opened this quarter| Ticker | Company | Shares | Value | Open |
|---|---|---|---|---|
| GTX | Garrett Motion Inc. | 1,500,000 | $54,345,000 | |
| BWA | Borgwarner Inc | 600,000 | $39,840,000 | |
| DNOW | DNOW Inc. | 3,000,000 | $38,910,000 | |
| ST | Sensata Technologies Holding plc | 600,000 | $28,644,000 | |
| SHLS | Shoals Technologies Group, Inc. | 2,255,000 | $22,324,500 | |
| EQPT | EquipmentShare.com Inc | 1,064,830 | $20,934,557 | |
| MEI | Methode Electronics Inc | 877,500 | $16,646,175 | |
| No positions match the current search. | ||||
Sold Out
Positions the filer fully exited| Ticker | Company | Shares | Value | Open |
|---|---|---|---|---|
| ROG | Rogers Corp | 475,000 | $50,981,750 | |
| NOVT | Novanta Inc | 375,000 | $44,291,250 | |
| DXPE | Dxp Enterprises Inc | 260,000 | $36,329,800 | |
| CDNL | Cardinal Infrastructure Group Inc. | 874,000 | $34,658,470 | |
| GVA | Granite Construction Inc | 250,000 | $29,970,000 | |
| CTS | Cts Corp | 584,000 | $27,891,840 | |
| No positions match the current search. | ||||
| Ticker | Company | Type | Shares | Value (USD) | % of Portfolio | History |
|---|---|---|---|---|---|---|
| WMS |
Advanced Drainage Systems, Inc.
Industrials
|
Held | 390,000 | $61,214,400 | 7.39% | |
| HLIO |
Helios Technologies, Inc.
Industrials
|
Reduced | 681,000 | $60,779,250 | 7.34% | |
| LFUS |
Littelfuse Inc
Technology
|
Reduced | 125,000 | $56,916,250 | 6.88% | |
| JHX |
James Hardie Industries plc
Basic Materials
|
Held | 2,100,000 | $54,978,000 | 6.64% | |
| GTX |
Garrett Motion Inc.
Consumer Cyclical
|
NEW | 1,500,000 | $54,345,000 | 6.56% | |
| CNM |
Core & Main, Inc.
Industrials
|
Added | 1,090,000 | $52,592,500 | 6.35% | |
| EXP |
Eagle Materials Inc
Basic Materials
|
Added | 220,000 | $49,500,000 | 5.98% | |
| ATS |
ATS Corp
Industrials
|
Reduced | 1,500,000 | $43,170,000 | 5.21% | |
| ASTE |
Astec Industries Inc
Industrials
|
Reduced | 690,276 | $42,237,988 | 5.10% | |
| MTRN |
MATERION Corp
Basic Materials
|
Reduced | 135,000 | $40,147,650 | 4.85% | |
| BWA |
Borgwarner Inc
Consumer Cyclical
|
NEW | 600,000 | $39,840,000 | 4.81% | |
| DNOW |
DNOW Inc.
Industrials
|
NEW | 3,000,000 | $38,910,000 | 4.70% | |
| MBC |
MasterBrand, Inc.
Consumer Cyclical
|
Held | 3,700,000 | $38,073,000 | 4.60% | |
| SITE |
SiteOne Landscape Supply, Inc.
Industrials
|
Held | 330,000 | $37,755,300 | 4.56% | |
| SWIM |
Latham Group, Inc.
Industrials
|
Added | 5,660,000 | $36,620,200 | 4.42% | |
| CLFD |
Clearfield, Inc.
Technology
|
Added | 810,200 | $32,237,858 | 3.89% | |
| ST |
Sensata Technologies Holding plc
Technology
|
NEW | 600,000 | $28,644,000 | 3.46% | |
| SHLS |
Shoals Technologies Group, Inc.
Technology
|
NEW | 2,255,000 | $22,324,500 | 2.70% | |
| EQPT |
EquipmentShare.com Inc
Industrials
|
NEW | 1,064,830 | $20,934,557 | 2.53% | |
| MEI |
Methode Electronics Inc
Technology
|
NEW | 877,500 | $16,646,175 | 2.01% |
Covers the securities this platform tracks: U.S.-listed common stock and the put/call positions reported on it. A 13F can also report security types outside that coverage — preferred shares, bonds, warrants, untracked share classes — so the filing's own declared total can exceed the figures above. The source filing is linked at the top of this table.