Mountaineer Partners Management, LLC

Q3 2026 13F-HR Holdings

Location
New York, NY
Holdings as of
9/30/2026
Date filed
11/9/2026
Form type
13F-HR
Num holdings
14
Total value ($000)
$159,473
Net value change ($000)
+27,437 (20.8%)
New positions
5
Sold out positions
2
Turnover %
50.5%
Sector allocation + QoQ delta (equities-only)
Prev filing: 8/13/2026 Next filing: — SEC filing

Snapshot: Change Analysis

Compared to Q2 2026
Methodology: sector metrics are equities-only; instrument mix chart is ex-options; options exposure is shown separately. Why this matters.
Top Adds (Value $000, Stocks/ETFs)
HBM 12,918 NEW
VSH 12,734 NEW
FLEX 12,509 NEW
MIDERA FOOD PROCESSING INC 11,007 NEW
HONA 10,350 NEW
ARDAGH METAL PACKAGING S A 4,752 174.6%
CCJ 684 16.8%
Top Reduces (Value $000, Stocks/ETFs)
MIDD -11,617 -100.0%
HMY -9,323 -100.0%
CRS -4,764 -37.0%
SXT -3,638 -22.4%
CSTM -3,264 -21.2%
SARO -2,566 -18.5%
AA -1,234 -11.4%
ATI -771 -6.5%
CENX -340 -1.5%
Instrument mix + QoQ Δ (ex-options)
How this table is calculated: SEC VALUE ($000) is used as reported. For derivatives (PUT/CALL/WARRANT/RIGHT), SEC value represents reported underlying exposure, not premium cash paid/received. Column % is bucket-based: non-options share is calculated inside non-option total, options share is calculated inside options total. Details.
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Instrument:
Issuer Name Ticker Sector Industry Class History Value ($000) % Shares Shares Δ Shares Δ% Value Δ ($000) Value Δ% Principal Option Type