ACK Asset Management LLC 13F: Quarter-over-Quarter Portfolio Changes
ACK Asset Management LLC reported a disclosed portfolio value of approximately $856.3 million in its latest SEC Form 13F-HR filing for Q2 2026, up 6.9% quarter on quarter. Over the quarter, the fund initiated 7 new positions, bought more shares in 5 holdings, trimmed 5 holdings, and exited 6 positions.
ACK Asset Management LLC's top buy was a new stake in Garrett Motion INC (GTX) , equal to 6.3% of the disclosed portfolio. Its top sell was Rogers CORP (ROG) . The fund exited the position completely after it had accounted for 6.4% of the previous portfolio.
New PositionsQ2 2026
Securities disclosed for the first time in Q2 2026 that were not present in the prior 13F-HR filing.
| Company | Ticker | Initial Portfolio Weight | History |
|---|---|---|---|
| GARRETT MOTION INC | GTX | 6.3% | History → |
| BORGWARNER INC | BWA | 4.7% | Holders → |
| DNOW INC | DNOW | 4.5% | Holders → |
| SENSATA TECHNOLOGIES HLDG PL | ST | 3.3% | Holders → |
| SHOALS TECHNOLOGIES GROUP IN | SHLS | 2.6% | Holders → |
| EQUIPMENTSHARE COM INC | EQPT | 2.4% | Holders → |
| MEI | MEI | 1.9% | Holders → |
Top BuysQ2 2026
The fund's top buys among existing positions in Q2 2026. Ranked by portfolio-weight impact, with the percentage of additional shares shown separately.
| Company | Ticker | Portfolio Weight Change | More Shares | History |
|---|---|---|---|---|
| EAGLE MATLS INC | EXP | +1.9% | +33.3% | History → |
| AERO-SWX | MTASF | +-0.0% | +30.4% | Holders → |
| CORE & MAIN INC | CNM | +0.6% | +21.1% | History → |
| CLEARFIELD INC | CLFD | +1.3% | +10.2% | Holders → |
| LATHAM GROUP | SWIM | +0.8% | +9.7% | Holders → |
Top SellsQ2 2026
The fund's top sells among positions it retained in Q2 2026. Ranked by portfolio-weight impact. Full exits are listed separately.
| Company | Ticker | Portfolio Weight Change | Shares Sold | History |
|---|---|---|---|---|
| MATERION CORP | MTRN | -3.9% | 71.6% | History → |
| ATS CORPORATION | ATS | -1.5% | 18.8% | History → |
| HLIO | HLIO | 0.8% | 12.7% | History → |
| ASTE | ASTE | -0.4% | 12.2% | History → |
| LITTELFUSE INC | LFUS | 0.9% | 7.4% | History → |
Full ExitsQ2 2026
Positions present in the prior 13F-HR filing that no longer appear in Q2 2026.
| Company | Ticker | Last-Reported Portfolio Weight |
|---|---|---|
| ROGERS CORP | ROG | 6.4% |
| NOVANTA INC | NOVT | 5.5% |
| DXP ENTERPRISES INC | DXPE | 4.5% |
| CARDINAL INFRASTRUCTURE GROU | CDNL | 4.3% |
| GRANITE CONSTR INC | GVA | 3.7% |
| CTS | CTS | 3.5% |
Net Portfolio Value ChangeQ2 2026
- $0.8BPrior quarter
- $0.9BCurrent quarter
- +$0.1BNet delta
- +6.9%% change
Methodology & FAQ
How ACK Asset Management LLC Quarterly Changes Are Computed
All deltas are sourced from sequential SEC Form 13F-HR filings for ACK Asset Management LLC: each row joins the most recent filing against the immediately preceding quarterly filing for the same fund. Share-count changes reflect reported trading activity, while portfolio weights can also move because of market price changes. Portfolio weights are normalized to exclude listed options for comparability. A complete description, including how confidential treatment filings are handled, is documented in the Methodology.
What stocks did ACK Asset Management LLC buy in Q2 2026?
In Q2 2026, ACK Asset Management LLC initiated 7 new positions (GARRETT MOTION INC (GTX), BORGWARNER INC (BWA), DNOW INC (DNOW), SENSATA TECHNOLOGIES HLDG PL (ST), SHOALS TECHNOLOGIES GROUP IN (SHLS), EQUIPMENTSHARE COM INC (EQPT), MEI (MEI)); bought more shares of EAGLE MATLS INC (EXP), AERO-SWX (MTASF), CORE & MAIN INC (CNM), CLEARFIELD INC (CLFD), LATHAM GROUP (SWIM).
What stocks did ACK Asset Management LLC sell in Q2 2026?
In Q2 2026, ACK Asset Management LLC fully sold 6 positions (ROGERS CORP (ROG), NOVANTA INC (NOVT), DXP ENTERPRISES INC (DXPE), CARDINAL INFRASTRUCTURE GROU (CDNL), GRANITE CONSTR INC (GVA), CTS (CTS)); reduced holdings in MATERION CORP (MTRN), ATS CORPORATION (ATS), HLIO (HLIO), ASTE (ASTE), LITTELFUSE INC (LFUS).
Which positions did ACK Asset Management LLC initiate in Q2 2026?
ACK Asset Management LLC established 7 new positions in Q2 2026: GARRETT MOTION INC (GTX, 6.3%), BORGWARNER INC (BWA, 4.7%), DNOW INC (DNOW, 4.5%), SENSATA TECHNOLOGIES HLDG PL (ST, 3.3%), SHOALS TECHNOLOGIES GROUP IN (SHLS, 2.6%), EQUIPMENTSHARE COM INC (EQPT, 2.4%), MEI (MEI, 1.9%).
Which existing positions saw the largest allocation increases for ACK Asset Management LLC in Q2 2026?
Of 5 existing positions with share-count increases in Q2 2026, the largest were: EAGLE MATLS INC (EXP, +1.9% weight, +33.3% shares), AERO-SWX (MTASF, +-0.0% weight, +30.4% shares), CORE & MAIN INC (CNM, +0.6% weight, +21.1% shares), CLEARFIELD INC (CLFD, +1.3% weight, +10.2% shares), LATHAM GROUP (SWIM, +0.8% weight, +9.7% shares).
Which positions did ACK Asset Management LLC fully exit in Q2 2026?
ACK Asset Management LLC fully exited 6 positions in Q2 2026: ROGERS CORP (ROG, last-reported weight 6.4%), NOVANTA INC (NOVT, last-reported weight 5.5%), DXP ENTERPRISES INC (DXPE, last-reported weight 4.5%), CARDINAL INFRASTRUCTURE GROU (CDNL, last-reported weight 4.3%), GRANITE CONSTR INC (GVA, last-reported weight 3.7%), CTS (CTS, last-reported weight 3.5%).
Which existing positions saw the largest allocation reductions for ACK Asset Management LLC in Q2 2026?
Of 5 existing positions with share-count reductions in Q2 2026, the largest were: MATERION CORP (MTRN, -3.9% weight, -71.6% shares), ATS CORPORATION (ATS, -1.5% weight, -18.8% shares), HLIO (HLIO, 0.8% weight, -12.7% shares), ASTE (ASTE, -0.4% weight, -12.2% shares), LITTELFUSE INC (LFUS, 0.9% weight, -7.4% shares).
Do quarter-over-quarter 13F allocation changes constitute explicit trading signals?
No. Quarter-over-quarter changes reflect a combination of active trading and market price movement. A weight increase can result from price appreciation alone, without the manager adding shares. Share-count delta is the cleaner indicator of explicit trading activity. All deltas on this page are sourced from sequential SEC Form 13F-HR filings.