Mountaineer Partners Management, LLC holds a focused book of 16 stocks worth $201.3M as of Q1 2026 (disclosed May 15, 2026, a ~45-day 13F lag). This quarter they opened Harmony Gold MNG-Spon ADR and trimmed Century Aluminum Company. Their largest long position is Century Aluminum Company at 17% of the equity book.
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This fund page is the Follow view. The Build view lets your agent pull holdings, quarter changes, overlap, and source filings through API or MCP.
curl -H "Authorization: Bearer YOUR_API_KEY" \ "https://arkolith.com/api/v1/funds/1730532/holdings"
Use Arkolith to show Mountaineer Partners Management, LLC's latest holdings, largest changes, and filing provenance.
Top-heavy: focused book
Share of the disclosed book in its largest positions. A higher top-5 share means a more concentrated, higher-conviction portfolio.
100% mapped to company sectors
Direct operating-company sectors from our SIC-based security master. ETF/fund and unclassified holdings stay visible separately; this is not ETF look-through exposure.
Estimated $ traded · quarter-end prices, no cost basis
Bars show each stock's share of the portfolio. Click a row for its position history.
| # | Security | Value | Shares | % Port | Last move | History |
|---|---|---|---|---|---|---|
| 1 | Century Alum Co COM | $34.3M | 584.0K | 17.0% | ▼−4.0% Reduced · −24K sh | |
| 2 | Constellium SE CL A SHS | $16.2M | 658.5K | 8.0% | ▼−3.4% Reduced · −23K sh | |
| 3 | Alcoa Corp COM | $15.5M | 233.7K | 7.7% | ▼−3.4% Reduced · −8K sh | |
| 4 | Hudbay Minerals Inc COM | $14.8M | 706.0K | 7.3% | ▼−10% Reduced · −81K sh | |
| 5 | Freeport McMoran Inc CL B | $14.2M | 241.0K | 7.0% | ▼−9.5% Reduced · −25K sh | |
| 6 | Carpenter Technology Corp COM | $14.2M | 35.9K | 7.0% | ▼−2.1% Reduced · −761 sh | |
| 7 | Sensient Technologies Corp COM | $13.5M | 156.6K | 6.7% | ▲+34% Added · +39K sh | |
| 8 | Ati Inc COM | $13.4M | 91.8K | 6.6% | ▼−29% Reduced · −37K sh | |
| 9 | Kirby Corp COM | $11.8M | 89.0K | 5.9% | ▲+1.8% Added · +2K sh | |
| 10 | Standardaero Inc COM | $10.5M | 407.4K | 5.2% | ▲+11% Added · +40K sh | |
| 11 | Harmony Gold MNG Ltd SPONSORED ADR | $10.2M | 666.7K | 5.1% | ▲New New position | |
| 12 | D R Horton Inc COM | $9.1M | 66.5K | 4.5% | ▲+2.4% Added · +2K sh | |
| 13 | Builders Firstsource Inc COM | $8.1M | 98.2K | 4.0% | ▲+4.4% Added · +4K sh | |
| 14 | Ardagh Metal Packaging S A SHS | $7.6M | 1.88M | 3.8% | ▲+28% Added · +409K sh | |
| 15 | Cameco Corp COM | $4.6M | 42.4K | 2.3% | —Held | |
| 16 | Frontier Group Hldgs Inc COM | $3.4M | 953.4K | 1.7% | —Held |
As-of date vs the date the SEC received each filing
Holdings from SEC EDGAR 13F-HR filings, updated quarterly ~45 days after quarter-end. Public domain. The book and weighting are long equity only; disclosed put/call options are listed separately and excluded from those totals. Price-derived performance is withheld until the price-source policy and freshness gate are green.