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Mountaineer Partners Management, LLC 13F holdings, Q3 2025

Holdings as of September 30, 2025 · filings on SEC EDGAR · latest filing →

Mountaineer Partners Management, LLC disclosed 18 US equity positions worth $171.9m in its Q3 2025 13F filing. The largest position was CENX at 11.3% of the reported book, followed by ECG and HBM. Against the Q2 2025 filing, it opened 2 new positions, added to 3 and reduced 7 among the top 18 holdings.

← Q2 2025 · Q4 2025 →

What did Mountaineer Partners Management, LLC own in Q3 2025? Top 18 positions

#StockSectorWeightValueSharesΔ sharesvs Q2 2025
1 CENX CENTURY ALUM CO Basic Materials 11.3%$19.4m661,043 -6% reduced
2 ECG EVERUS CONSTR GROUP 8.5%$14.6m169,844 -18% reduced
3 HBM HUDBAY MINERALS INC Basic Materials 8.4%$14.5m955,419 -15% reduced
4 CSTM CONSTELLIUM SE Basic Materials 7.2%$12.4m833,776 -1% reduced
5 ATI ATI INC Industrials 6.8%$11.7m144,020 17% added
6 FCX FREEPORT-MCMORAN INC Basic Materials 6.7%$11.5m294,049 16% added
7 ENTG ENTEGRIS INC Technology 6.6%$11.4m123,234 -2% reduced
8 VSH VISHAY INTERTECHNOLOGY INC Technology 6.6%$11.4m742,177 -0% held
9 CRS CARPENTER TECHNOLOGY CORP Industrials 5.8%$10.0m40,849 2% added
10 AA ALCOA CORP Basic Materials 5.7%$9.8m296,642 -3% reduced
11 SARO STANDARDAERO INC Industrials 4.6%$7.9m290,730 0% held
12 BLDR BUILDERS FIRSTSOURCE INC Industrials 4.3%$7.4m60,759 -3% reduced
13 AMBP ARDAGH METAL PACKAGING S A Consumer Cyclical 3.6%$6.1m1,538,484 0% held
14 KEX KIRBY CORP Industrials 3.2%$5.5m65,431 0% held
15 NXE NEXGEN ENERGY LTD Energy 2.9%$5.1m564,507 0% held
16 DHI D R HORTON INC Consumer Cyclical 2.7%$4.7m27,876 – new
17 SAN JUAN BASIN RTY TR 2.5%$4.3m719,054 0% held
18 UEC URANIUM ENERGY CORP Energy 2.5%$4.3m320,952 – new

Weights are shares of the reported long US equity book (options excluded). Values are as filed, normalised to whole dollars. Share changes compare against the immediately preceding filing only.