Mountaineer Partners Management, LLC
Long book
$201.3M
Q1 2026
Positions
16
Top-10 weight
79%
concentration
Last quarter
+9.1%
SPY +14.8%
Turnover
17%
of book per quarter
Strategy in plain words
auto-generated from filingsMountaineer Partners Management, LLC is a concentrated fundamental stock-picker, specialised in industrials (68% of the long book), running a $201.3M US long book across 16 positions.
The portfolio is extremely concentrated — the top 10 positions are almost the whole book. Turnover is modest: positions are typically held for years. Current anchor positions: CENTURY ALUMINUM COMPANY, CONSTELLIUM SE, ALCOA CORP, HUDBAY MINERALS INC, FREEPORT-MCMORAN INC.
Over the last 9 quarters its long book ran on average 0.7pp per quarter ahead of the S&P 500, beating the index in 4 of 9 quarters. We rate its filings highest-signal: new buys here are worth attention.
Implied long-book return vs S&P 500
methodology: positions priced quarterly, no shorts/options Fund long book S&P 500
Q1 2024
-0.3%
Q2 2024
-4.5%
Q3 2024
-9.8%
Q4 2024
-10.3%
Q1 2025
+19.6%
Q2 2025
+10.8%
Q3 2025
+17.3%
Q4 2025
+15.1%
Q1 2026
+9.1%
Sector allocation
Industrials 71%
Materials 18%
Other 7%
Consumer discretionary 4%
Long book by quarter
What does Mountaineer Partners own?
Q1 2026 13F| Company | Sector | Shares | Value | % of book | Change |
|---|---|---|---|---|---|
| CENX CENTURY ALUMINUM COMPANY | Industrials | 584.0K | $34.3M | 17.0% | -4.0% |
| CSTM CONSTELLIUM SE | Industrials | 658.5K | $16.2M | 8.0% | -3.4% |
| AA ALCOA CORP | Industrials | 233.7K | $15.5M | 7.7% | -3.4% |
| HBM HUDBAY MINERALS INC | Materials | 706.0K | $14.8M | 7.3% | -10.3% |
| FCX FREEPORT-MCMORAN INC | Materials | 241.0K | $14.2M | 7.0% | -9.5% |
| CRS CARPENTER TECHNOLOGY | Industrials | 35.9K | $14.2M | 7.0% | -2.1% |
| SXT SENSIENT TECHNOLOGIES CORP | Other | 156.6K | $13.5M | 6.7% | +33.7% |
| ATI ATI INC | Industrials | 91.8K | $13.4M | 6.6% | -28.8% |
| KEX KIRBY CORP | Industrials | 89.0K | $11.8M | 5.9% | +1.8% |
| SARO STANDARDAERO INC | Industrials | 407.4K | $10.5M | 5.2% | +10.9% |
| DHI DR HORTON INC | Industrials | 66.5K | $9.1M | 4.5% | +2.4% |
| BLDR BUILDERS FIRSTSOURCE INC | Consumer discretionary | 98.2K | $8.1M | 4.0% | +4.4% |
| AMBP ARDAGH METAL PACKAGING SA | Industrials | 1.9M | $7.6M | 3.8% | +27.8% |
| CCJ CAMECO CORP | Materials | 42.4K | $4.6M | 2.3% | Held |
| ULCC FRONTIER GROUP HOLDINGS INC | Industrials | 953.4K | $3.4M | 1.7% | Held |
13F filing history
| Period | Form | Filed | Entries | Reported value | Flags | Source |
|---|---|---|---|---|---|---|
| Q1 2026 | 13F-HR | May 15, 2026 | 32 | $201.3M | canonical | SEC ↗ |
| Q4 2025 | 13F-HR | Feb 13, 2026 | 34 | $178.7M | canonical | SEC ↗ |
| Q3 2025 | 13F-HR | Nov 14, 2025 | 36 | $171.9M | canonical | SEC ↗ |
| Q2 2025 | 13F-HR | Aug 14, 2025 | 32 | $151.3M | canonical | SEC ↗ |
| Q1 2025 | 13F-HR | May 15, 2025 | 28 | $104.5M | canonical | SEC ↗ |
| Q4 2024 | 13F-HR | Feb 14, 2025 | 34 | $136.6M | canonical | SEC ↗ |
| Q3 2024 | 13F-HR/ARESTATEMENT | Nov 15, 2024 | 30 | $160.4M | canonical | SEC ↗ |
| Q3 2024 | 13F-HR | Nov 14, 2024 | 30 | $6.6M | SEC ↗ | |
| Q2 2024 | 13F-HR | Aug 14, 2024 | 32 | $192.2M | canonical | SEC ↗ |
| Q1 2024 | 13F-HR | May 15, 2024 | 32 | $216.6M | canonical | SEC ↗ |