Terminal · Institutions

Every 13F-reported equity position this quarter, with its quarter-over-quarter change — each row traces back to the SEC filing.

ACK Asset Management LLC 13F Holdings -- Portfolio & Top Positions (2026-03-31)

ACK Asset Management LLC (CIK 1510940) reported $801.1M across 18 reported positions in its SEC 13F filing for 2026-03-31. Largest positions: MTRN ($68.7M, 8.57%), WMS ($53.5M, 6.68%), ATS ($52.1M, 6.50%), ROG ($51.0M, 6.36%), HLIO ($50.5M, 6.30%). Source: SEC Form 13F.

RankTickerCompanyValue% PortfolioSharesAction
1MTRNMTRN$68.7M8.57%474,800Hold
2WMSWMS$53.5M6.68%390,000Hold
3ATSATS$52.1M6.50%1.8MHold
4ROGROG$51.0M6.36%475,000Added
5HLIOHLIO$50.5M6.30%780,378Hold
6LFUSLFUS$45.8M5.72%135,000New
7CNMCNM$44.5M5.55%900,000Hold
8NOVTNOVT$44.3M5.53%375,000Hold
9SITESITE$43.9M5.48%330,000Hold
10ASTEASTE$42.3M5.29%786,500Hold
11JHXJHX$39.8M4.96%2.1MHold
12DXPEDXPE$36.3M4.53%260,000Added
13CDNL$34.7M4.33%874,000Added
14EXPEXP$31.3M3.90%165,000Hold
15MBCMBC$30.7M3.84%3.7MAdded
16GVAGVA$30.0M3.74%250,000Trimmed
17CTSCTS$27.9M3.48%584,000New
18SWIMSWIM$27.7M3.46%5.2MNew
19AERO-SWX$26.8M3.35%830,000Added
20CLFDCLFD$19.5M2.43%735,200Added
21AINAIN$00.00%0Exited
22APOGAPOG$00.00%0Exited
23ATROATRO$00.00%0Exited
24CTOSCTOS$00.00%0Exited
25ERIIERII$00.00%0Exited

Source: SEC Form 13F filings · as of 2026-03-31