Mountaineer Partners Management
New York, NYfiles as Mountaineer Partners Management, LLC
$137m in 11 US stocks at the end of 30 June 2026. The top 10 are 97.0% of the money. It changed about 30.6% of the portfolio this quarter.
Value
$137m
Stocks
11
Top 10 share
97.0%
Turnover
30.6%
What changed this quarter
New
Bought for the first time this quarter.
- MiddlebyMIDD8.5% of the fund
Added
Bought more of a stock they already held.
- StandardAeroSARO10.1% of the fund+14%
Cut
Sold some of their stake.
- Century AluminumCENX16.8% of the fund-14%
- Sensient TechnologiesSXT11.8% of the fund-16%
- Constellium SECSTM11.2% of the fund-27%
- Carpenter TechnologyCRS9.4% of the fund-42%
- ATIATI8.7% of the fund-34%
- AlcoaAA7.9% of the fund-11%
- Harmony Gold MiningHMY6.8% of the fund-8%
- Ardagh Metal PackagingAMBP5.9% of the fund-8%
- CamecoCCJ3.0% of the fund-6%
Sold out
Sold their entire stake.
- Hudbay MineralsHBM-100%
- Freeport-McMoRanFCX-100%
- KirbyKEX-100%
- Horton D RDHI-100%
- Builders FirstSourceBLDR-100%
- Frontier Group HoldingsULCC-100%
Holdings
- CamecoCCJ
- Share
- 3.0%
- Value
- $4m
- Shares
- 39,903
-6%
| Company | Share of fund | Value | Shares | Change |
|---|---|---|---|---|
| Century AluminumCENX | 16.8% | $23m | 503,309 | -14% |
| Sensient TechnologiesSXT | 11.8% | $16m | 131,727 | -16% |
| Constellium SECSTM | 11.2% | $15m | 482,130 | -27% |
| StandardAeroSARO | 10.1% | $14m | 464,595 | +14% |
| Carpenter TechnologyCRS | 9.4% | $13m | 20,894 | -42% |
| ATIATI | 8.7% | $12m | 60,419 | -34% |
| MiddlebyMIDD | 8.5% | $12m | 67,536 | New |
| AlcoaAA | 7.9% | $11m | 208,165 | -11% |
| Harmony Gold MiningHMY | 6.8% | $9m | 612,949 | -8% |
| Ardagh Metal PackagingAMBP | 5.9% | $8m | 1,722,234 | -8% |
| CamecoCCJ | 3.0% | $4m | 39,903 | -6% |
Over time and by industry
Value over time
Jun '25
Dec '25
Jun '26
Value is down 9.1% since 30 June 2025.
Where the money is
Materials57.5%
Industrials42.5%
From the fund's 13F filings. They list US stocks and options only, 45 days after each quarter, and leave out cash, bonds, shorts and foreign shares.