Skip to content
Disclosery

Mountaineer Partners Management, LLC

Follow

13F filer, CIK 1730532, New York, NY

Mountaineer Partners Management, LLC reported $137,477,683 across 11 holdings for the quarter ended 2026-06-30, in a 13F-HR filed 2026-08-13. Its ten largest share positions make up 97.04% of the portfolio.

Filed (acceptance time not in the bulk data set), ingested 13F-HR 0000919574-26-005107

Period
2026-06-30
Reported value
$137M
Holdings
11
Top 10 weight
97.04%
New
1
Sold out
6

Largest buys vs the previous quarter

SecurityShares changeApprox. value
MIDDnew+67,536$11.6M
SAROadded+57,160$1.71M

Ranked by the share change valued at this quarter's implied price (value over shares in the 13F). A position sold out is valued at the previous quarter's price, its last report.

Largest sells vs the previous quarter

SecurityShares changeApprox. value
HBMexited-706,040-$14.8M
FCXexited-240,973-$14.2M
KEXexited-89,017-$11.8M
CRSreduced-15,035-$9.27M
DHIexited-66,541-$9.13M

Ranked by the share change valued at this quarter's implied price (value over shares in the 13F). A position sold out is valued at the previous quarter's price, its last report.

Holdings, Q2 2026

Share positions as resolved from 13F-HR 0000919574-26-005107, largest first. % of portfolio is the value over $137,477,683, the sum of the share positions whose value is usable for ratios (method).

SecurityHistorySharesValue% of portfolioChangeLatest eventTimeline
CENXCENTURY ALUM COQuarterly shares; oldest to newest; scale is this security's eight-quarter maximum; 2024Q3: not loaded; 2024Q4: not loaded; 2025Q1: not loaded; 2025Q2: not loaded; 2025Q3: not loaded; 2025Q4: not loaded; 2026Q1: 583,997 shares; 2026Q2: 503,309 shares 503,309$23.2M16.84%-80,688Timeline
SXTSENSIENT TECHNOLOGIES CORPQuarterly shares; oldest to newest; scale is this security's eight-quarter maximum; 2024Q3: not loaded; 2024Q4: not loaded; 2025Q1: not loaded; 2025Q2: not loaded; 2025Q3: not loaded; 2025Q4: not loaded; 2026Q1: 156,584 shares; 2026Q2: 131,727 shares 131,727$16.2M11.81%-24,857Timeline
CSTMCONSTELLIUM SEQuarterly shares; oldest to newest; scale is this security's eight-quarter maximum; 2024Q3: not loaded; 2024Q4: not loaded; 2025Q1: not loaded; 2025Q2: not loaded; 2025Q3: not loaded; 2025Q4: not loaded; 2026Q1: 658,490 shares; 2026Q2: 482,130 shares 482,130$15.4M11.18%-176,360Timeline
SAROSTANDARDAERO INCQuarterly shares; oldest to newest; scale is this security's eight-quarter maximum; 2024Q3: not loaded; 2024Q4: not loaded; 2025Q1: not loaded; 2025Q2: not loaded; 2025Q3: not loaded; 2025Q4: not loaded; 2026Q1: 407,435 shares; 2026Q2: 464,595 shares 464,595$13.9M10.11%+57,160Timeline
CRSCARPENTER TECHNOLOGY CORPQuarterly shares; oldest to newest; scale is this security's eight-quarter maximum; 2024Q3: not loaded; 2024Q4: not loaded; 2025Q1: not loaded; 2025Q2: not loaded; 2025Q3: not loaded; 2025Q4: not loaded; 2026Q1: 35,929 shares; 2026Q2: 20,894 shares 20,894$12.9M9.37%-15,035Timeline
ATIATI INCQuarterly shares; oldest to newest; scale is this security's eight-quarter maximum; 2024Q3: not loaded; 2024Q4: not loaded; 2025Q1: not loaded; 2025Q2: not loaded; 2025Q3: not loaded; 2025Q4: not loaded; 2026Q1: 91,784 shares; 2026Q2: 60,419 shares 60,419$11.9M8.66%-31,365Timeline
MIDDMIDDLEBY CORPQuarterly shares; oldest to newest; scale is this security's eight-quarter maximum; 2024Q3: not loaded; 2024Q4: not loaded; 2025Q1: not loaded; 2025Q2: not loaded; 2025Q3: not loaded; 2025Q4: not loaded; 2026Q1: not reported; 2026Q2: 67,536 shares 67,536$11.6M8.45%newTimeline
AAALCOA CORPQuarterly shares; oldest to newest; scale is this security's eight-quarter maximum; 2024Q3: not loaded; 2024Q4: not loaded; 2025Q1: not loaded; 2025Q2: not loaded; 2025Q3: not loaded; 2025Q4: not loaded; 2026Q1: 233,687 shares; 2026Q2: 208,165 shares 208,165$10.9M7.89%-25,522Timeline
HMYHARMONY GOLD MNG LTDQuarterly shares; oldest to newest; scale is this security's eight-quarter maximum; 2024Q3: not loaded; 2024Q4: not loaded; 2025Q1: not loaded; 2025Q2: not loaded; 2025Q3: not loaded; 2025Q4: not loaded; 2026Q1: 666,735 shares; 2026Q2: 612,949 shares 612,949$9.32M6.78%-53,786Timeline
AMBPARDAGH METAL PACKAGING S AQuarterly shares; oldest to newest; scale is this security's eight-quarter maximum; 2024Q3: not loaded; 2024Q4: not loaded; 2025Q1: not loaded; 2025Q2: not loaded; 2025Q3: not loaded; 2025Q4: not loaded; 2026Q1: 1,878,082 shares; 2026Q2: 1,722,234 shares 1,722,234$8.16M5.94%-155,848Timeline
CCJCAMECO CORPQuarterly shares; oldest to newest; scale is this security's eight-quarter maximum; 2024Q3: not loaded; 2024Q4: not loaded; 2025Q1: not loaded; 2025Q2: not loaded; 2025Q3: not loaded; 2025Q4: not loaded; 2026Q1: 42,424 shares; 2026Q2: 39,903 shares 39,903$4.06M2.96%-2,521Timeline

Sold out in Q2 2026

Positions in the previous quarter's report that this quarter's report no longer lists.

SecurityShares beforeValue beforeType
HBMHUDBAY MINERALS INC706,040$14.8Mshares
FCXFREEPORT MCMORAN INC240,973$14.2Mshares
KEXKIRBY CORP89,017$11.8Mshares
DHID R HORTON INC66,541$9.13Mshares
BLDRBUILDERS FIRSTSOURCE INC98,203$8.09Mshares
ULCCFRONTIER GROUP HLDGS INC953,375$3.37Mshares

How Q2 2026 was built

Available 13F filings of this filer for the quarter and their roles: the base report is the latest original or restatement, NEW HOLDINGS amendments filed after it are added (method).

FilingRoleAmendmentFiledAcceptedIngested
13F-HR 0000919574-26-005107 base2026-08-13acceptance time not in the bulk data set
13F-HR/A 0000919574-26-005443 addednew holdings2026-08-14acceptance time not in the bulk data set