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Mountaineer Partners Management, LLC 13F holdings, Q4 2025

Holdings as of December 31, 2025 · filings on SEC EDGAR · latest filing →

Mountaineer Partners Management, LLC disclosed 17 US equity positions worth $178.7m in its Q4 2025 13F filing. The largest position was CENX at 13.3% of the reported book, followed by HBM and ATI. Against the Q3 2025 filing, it opened 3 new positions, added to 5 and reduced 9 among the top 17 holdings.

← Q3 2025 · Q1 2026 →

What did Mountaineer Partners Management, LLC own in Q4 2025? Top 17 positions

#StockSectorWeightValueSharesΔ sharesvs Q3 2025
1 CENX CENTURY ALUM CO Basic Materials 13.3%$23.8m608,475 -8% reduced
2 HBM HUDBAY MINERALS INC Basic Materials 8.7%$15.6m787,247 -18% reduced
3 ATI ATI INC Industrials 8.3%$14.8m128,909 -10% reduced
4 FCX FREEPORT-MCMORAN INC Basic Materials 7.6%$13.5m266,327 -9% reduced
5 AA ALCOA CORP Basic Materials 7.2%$12.9m241,994 -18% reduced
6 CSTM CONSTELLIUM SE Basic Materials 7.2%$12.8m681,464 -18% reduced
7 CRS CARPENTER TECHNOLOGY CORP Industrials 6.5%$11.6m36,690 -10% reduced
8 SXT SENSIENT TECHNOLOGIES CORP Basic Materials 6.2%$11.0m117,090 – new
9 SARO STANDARDAERO INC Industrials 5.9%$10.5m367,498 26% added
10 BLDR BUILDERS FIRSTSOURCE INC Industrials 5.4%$9.7m94,091 55% added
11 KEX KIRBY CORP Industrials 5.4%$9.6m87,444 34% added
12 DHI D R HORTON INC Consumer Cyclical 5.2%$9.4m65,004 133% added
13 AMBP ARDAGH METAL PACKAGING S A Consumer Cyclical 3.4%$6.0m1,469,480 -4% reduced
14 NXE NEXGEN ENERGY LTD Energy 2.8%$4.9m538,042 -5% reduced
15 ULCC FRONTIER GROUP HLDGS INC Industrials 2.5%$4.5m953,375 – new
16 SAN JUAN BASIN RTY TR 2.3%$4.1m732,351 2% added
17 CCJ CAMECO CORP Energy 2.2%$3.9m42,424 – 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.