ACK Asset Management LLC
An institutional investment manager in GREENWICH, CT. Its Form 13F for the quarter ended Jun 30, 2026, filed Aug 13, 2026. SEC CIK 1510940.
- Reported value$856.3m
- Positions21
Holdings: 21 positions
The filing on sec.govAs filed, largest first. Reported value is what the manager stated for each position at the quarter end, in US dollars; it is filing data, not a price. Weight is the position's share of the total reported value. Changes compare with the 13F for the quarter ended 2026-03-31.
| Issuer | Class | CUSIP | Reported value$m | Weight | Shares | Put or call | Change on the quarter before |
|---|---|---|---|---|---|---|---|
| WMSWMS | COM | 00790R104 | 61.2 | 7.1% | 390,000 | Unchanged | |
| HlioHLIO | COM | 42328H109 | 60.8 | 7.1% | 681,000 | Reduced−99,378 | |
| LfusLFUS | COM | 537008104 | 56.9 | 6.6% | 125,000 | Reduced−10,000 | |
| JHX | COM | G4253H101 | 55.0 | 6.4% | 2,100,000 | Unchanged | |
| GTXGTX | COM | 366505105 | 54.3 | 6.3% | 1,500,000 | New+1,500,000 | |
| CNMCNM | COM | 21874C102 | 52.6 | 6.1% | 1,090,000 | Added+190,000 | |
| EXPEXP | COM | 26969P108 | 49.5 | 5.8% | 220,000 | Added+55,000 | |
| ATSATS | COM | 00217Y104 | 43.2 | 5.0% | 1,500,000 | Reduced−346,196 | |
| AsteASTE | COM | 046224101 | 42.2 | 4.9% | 690,276 | Reduced−96,224 | |
| MTRNMTRN | COM | 576690101 | 40.1 | 4.7% | 135,000 | Reduced−339,800 | |
| BWABWA | COM | 099724106 | 39.8 | 4.7% | 600,000 | New+600,000 | |
| DnowDNOW | COM | 67011P100 | 38.9 | 4.5% | 3,000,000 | New+3,000,000 | |
| MBCMBC | COM | 57638P104 | 38.1 | 4.4% | 3,700,000 | Unchanged | |
| SiteSITE | COM | 82982L103 | 37.8 | 4.4% | 330,000 | Unchanged | |
| SwimSWIM | COM | 51819L107 | 36.6 | 4.3% | 5,660,000 | Added+500,000 | |
| CLFDCLFD | COM | 18482P103 | 32.2 | 3.8% | 810,200 | Added+75,000 | |
| ST | COM | G8060N102 | 28.6 | 3.3% | 600,000 | New+600,000 | |
| Aero-Swx | COM | H55555108 | 28.5 | 3.3% | 1,082,500 | Added+252,500 | |
| SHLSSHLS | COM | 82489W107 | 22.3 | 2.6% | 2,255,000 | New+2,255,000 | |
| EqptEQPT | COM | 29445S100 | 20.9 | 2.4% | 1,064,830 | New+1,064,830 | |
| MEIMEI | COM | 591520200 | 16.6 | 1.9% | 877,500 | New+877,500 |
Sold out: 6 positions
Held at the end of the quarter before and not reported this quarter.
| Issuer | Class | CUSIP | Reported value$ | Weight | Shares | Put or call | Change on the quarter before |
|---|---|---|---|---|---|---|---|
| CDNLCDNL | COM | 14154A102 | 0.0 | 0.0% | 0 | Sold out−874,000 | |
| CTSCTS | COM | 126501105 | 0.0 | 0.0% | 0 | Sold out−584,000 | |
| DxpeDXPE | COM | 233377407 | 0.0 | 0.0% | 0 | Sold out−260,000 | |
| GVAGVA | COM | 387328107 | 0.0 | 0.0% | 0 | Sold out−250,000 | |
| NovtNOVT | COM | 67000B104 | 0.0 | 0.0% | 0 | Sold out−375,000 | |
| ROGROG | COM | 775133101 | 0.0 | 0.0% | 0 | Sold out−475,000 |
Source: SEC EDGAR, Form 13F-HR, accession 0001510940-26-000005 (on sec.gov). Last ingested by Listed: Oct 22, 2026, 05:26 ET. Listed shows no prices and gives no investment advice.