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Mountaineer Partners Management, LLC: 13F holdings, Q2 2026

Hedge fund · SEC EDGAR filings (CIK 1730532) · Explore on the interactive board

Mountaineer Partners Management, LLC disclosed 11 US equity positions worth $134.8m in its Q2 2026 13F filing (holdings as of June 30, 2026, filed August 14, 2026). Its largest position is CENX at 17.2% of the reported book, followed by SXT, CSTM. The top ten holdings are 97.0% of the book, and the portfolio behaves like about 9 equal-weight positions. Versus the prior filing it opened 1 new position, added to 1, reduced 9 and exited 6. Note: this manager's most recent filing is 3934 quarters behind the newest quarter on file, so these figures are history rather than current positioning.

This manager's most recent filing is 3934 quarter(s) behind the newest quarter on file. Treat these figures as history, not current positioning.
$134.8mreported US equity book
11positions
17.2%largest position
97.0%top 10 weight
9.44effective positions (1/HHI)
2quarters on file since Q1 2026

What does Mountaineer Partners Management, LLC own? Top holdings as of June 30, 2026

Change is measured in shares against the previous filing (Q1 2026), so price moves do not read as decisions. This quarter: 1 new, 1 added, 9 reduced, 6 exited.

#StockSectorWeightValueSharesΔ sharesAction
1 CENX CENTURY ALUM CO Basic Materials 17.2%$23.2m503,309 -14% reduced
2 SXT SENSIENT TECHNOLOGIES CORP Basic Materials 12.1%$16.2m131,727 -16% reduced
3 CSTM CONSTELLIUM SE Basic Materials 11.4%$15.4m482,130 -27% reduced
4 SARO STANDARDAERO INC Industrials 10.3%$13.9m464,595 14% added
5 CRS CARPENTER TECHNOLOGY CORP Industrials 9.6%$12.9m20,894 -42% reduced
6 ATI ATI INC Industrials 8.8%$11.9m60,419 -34% reduced
7 MIDD MIDDLEBY CORP Industrials 8.6%$11.6m67,536 new
8 AA ALCOA CORP Basic Materials 8.1%$10.9m208,165 -11% reduced
9 HMY HARMONY GOLD MNG LTD Basic Materials 6.9%$9.3m612,949 -8% reduced
10 AMBP ARDAGH METAL PACKAGING S A Consumer Cyclical 4.0%$5.4m1,148,027 -39% reduced
11 CCJ CAMECO CORP Energy 3.0%$4.1m39,903 -6% reduced

What did Mountaineer Partners Management, LLC sell? Positions exited since the previous filing

StockPrior weightPrior value
HBM HUDBAY MINERALS INC24.1%$14.8m
FCX FREEPORT MCMORAN INC23.1%$14.2m
KEX KIRBY CORP19.3%$11.8m
DHI D R HORTON INC14.9%$9.1m
BLDR BUILDERS FIRSTSOURCE INC13.2%$8.1m
ULCC FRONTIER GROUP HLDGS INC5.5%$3.4m

Sector mix

SectorWeight
Basic Materials55.6%
Industrials37.3%
Consumer Cyclical4.0%
Energy3.0%

Sectors cover positions whose ticker resolved to a sector; the remainder is unclassified, not cash.

Filing history

QuarterPositionsEquity value
Q2 202622$134.8m
Q1 202632$201.3m

How concentrated is Mountaineer Partners Management, LLC's portfolio?

Across every quarter Mountaineer Partners Management, LLC has filed, its median largest position is 17.1% of the book and its median top-ten weight is 87.8%, which WhaleCreep classifies as concentrated (the gate is a median largest position of 5%). Of 6.0 completed holding spells, the median lasted 1.0 quarters; 11.0 positions are still open and their final length is unknown.