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MASON CAPITAL MANAGEMENT LLC

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13F filer, CIK 1218735, NEW YORK, NY

MASON CAPITAL MANAGEMENT LLC reported $491,353,424 across 6 holdings for the quarter ended 2025-09-30, in a 13F-HR filed 2025-11-14.

Filed (acceptance time not in the bulk data set), ingested 13F-HR 0001104659-25-111862

Period
2025-09-30
Reported value
$491M
Holdings
6
Top 10 weight
100%
New
3
Sold out
1

Largest buys vs the previous quarter

SecurityShares changeApprox. value
KVUEnew+2,595,000$42.1M
BKDnew+2,475,964$21M
MLABnew+70,300$4.71M

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
COHENCIRCLEACQUISITIONCORexited-325,000-$3.57M

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, Q3 2025

Share positions as resolved from 13F-HR 0001104659-25-111862, largest first. % of portfolio is the value over $491,353,424, the sum of the share positions whose value is usable for ratios (method).

SecurityHistorySharesValue% of portfolioChangeLatest eventTimeline
ATSATS CORPORATIONQuarterly shares; oldest to newest; scale is this security's eight-quarter maximum; 2023Q4: restricted; 2024Q1: restricted; 2024Q2: restricted; 2024Q3: 14,914,765 shares; 2024Q4: 14,914,765 shares; 2025Q1: 15,563,568 shares; 2025Q2: 15,563,568 shares; 2025Q3: 15,563,568 shares 15,563,568$408M82.99%0Timeline
KVUEKENVUE INCQuarterly shares; oldest to newest; scale is this security's eight-quarter maximum; 2023Q4: restricted; 2024Q1: restricted; 2024Q2: restricted; 2024Q3: not reported; 2024Q4: not reported; 2025Q1: not reported; 2025Q2: not reported; 2025Q3: 2,595,000 shares 2,595,000$42.1M8.57%newTimeline
BKDBROOKDALE SR LIVING INCQuarterly shares; oldest to newest; scale is this security's eight-quarter maximum; 2023Q4: restricted; 2024Q1: restricted; 2024Q2: restricted; 2024Q3: not reported; 2024Q4: not reported; 2025Q1: not reported; 2025Q2: not reported; 2025Q3: 2,475,964 shares 2,475,964$21M4.27%newTimeline
CCOCLEAR CHANNEL OUTDOOR HLDGSQuarterly shares; oldest to newest; scale is this security's eight-quarter maximum; 2023Q4: restricted; 2024Q1: restricted; 2024Q2: restricted; 2024Q3: 9,828,401 shares; 2024Q4: 9,828,401 shares; 2025Q1: 9,828,401 shares; 2025Q2: 9,828,401 shares; 2025Q3: 9,828,401 shares 9,828,401$15.5M3.16%0Timeline
MLABMESA LABS INCQuarterly shares; oldest to newest; scale is this security's eight-quarter maximum; 2023Q4: restricted; 2024Q1: restricted; 2024Q2: restricted; 2024Q3: not reported; 2024Q4: not reported; 2025Q1: not reported; 2025Q2: not reported; 2025Q3: 70,300 shares 70,300$4.71M0.96%newTimeline
SBNYSIGNATURE BANKQuarterly shares; oldest to newest; scale is this security's eight-quarter maximum; 2023Q4: restricted; 2024Q1: restricted; 2024Q2: restricted; 2024Q3: 400,000 shares; 2024Q4: 400,000 shares; 2025Q1: 400,000 shares; 2025Q2: 400,000 shares; 2025Q3: 400,000 shares 400,000$260K0.05%0Timeline

Sold out in Q3 2025

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

SecurityShares beforeValue beforeType
COHENCIRCLEACQUISITIONCORCOHENCIRCLEACQUISITIONCOR325,000$3.57Mshares

How Q3 2025 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 0001104659-25-111862 base2025-11-14acceptance time not in the bulk data set