Mountaineer Partners Management, LLC

Position in CENX — Century Aluminum Co

CIK 1730532 New York, NY

Position in CENX

as of Mar 31, 2026 · filed May 15, 2026 Compact

Position Value

$34,274,783

+$10,434,733 QoQ

Shares Held

583,997

-4.0% QoQ

Ownership

0.590%

of shares outstanding

% of Portfolio

17.02%

of 13F equity value

Holder Rank

—

not a current holder

Holding Since

Dec 2021

16 quarters on record

Voting authority Sole 93.01606001400692.ToString("F0")% Shared 0.ToString("F0")% None 6.983939985993079.ToString("F0")%

Basic Materials · as of Mar 31, 2026

Mountaineer Partners Management, LLC holds $65,960,923 across 3 Aluminum names. CENX ranks #1 (52.0% of the industry book) .

#	Ticker	Company	Shares	Value (USD)
1	CENX	Century Aluminum Co This page	583,997	$34,274,783
2	CSTM	Constellium SE	658,490	$16,185,683
3	AA	Alcoa Corp	233,687	$15,500,457

16 filing rows on record

Report Date	Value (USD)	Shares	Change	Type	Discretion	Filed
2026-03-31	$34,274,783	583,997	-4.0%	Shares	Sole	2026-05-15
2025-12-31	$23,840,050	608,475	-8.0%	Shares	Sole	2026-02-13
2025-09-30	$19,408,222	661,043	-6.3%	Shares	Sole	2025-11-14
2025-06-30	$12,706,802	705,150	+10.3%	Shares	Sole	2025-08-14
2025-03-31	$11,866,762	639,373	-1.3%	Shares	Sole	2025-05-15
2024-12-31	$11,803,735	647,845	-54.0%	Shares	Sole	2025-02-14
2024-09-30	$22,849,096	1,407,831	+5.2%	Shares	Sole	2024-11-15
2024-06-30	$22,419,171	1,338,458	-37.5%	Shares	Sole	2024-08-14
2024-03-31	$32,966,964	2,142,103	-5.7%	Shares	Sole	2024-05-15
2023-12-31	$27,567,572	2,270,805	+11.5%	Shares	Sole	2024-02-14
2023-09-30	$14,637,890	2,035,868	+1.9%	Shares	Sole	2023-11-14
2023-06-30	$17,416,830	1,997,343	+81.0%	Shares	Sole	2023-08-14
2023-03-31	$11,032,010	1,103,201	+14.5%	Shares	Sole	2023-05-15
2022-12-31	$7,879,940	963,318	+76.2%	Shares	Sole	2023-02-14
2022-03-31	$14,382,124	546,641	-21.9%	Shares	Sole	2022-05-16
2021-12-31	$11,596,222	700,255	—	Shares	Sole	2022-02-14
No filing history on record for this holder in this stock.