Filed: 5/15/2026ACC: 0001104659-26-062410
📋 What this filing means
MASON CAPITAL MANAGEMENT LLC filed this quarterly 13F‑HR report disclosing 7 equity positions with a total reported market value of $612.85M. This filing provides a transparent view of the manager's long equity holdings as of the quarter end.
7
Positions
$612.85M
Total AUM (reported)
38.46M
Total Shares
Allocation by class
COM$605.85M98.9%
REIT$7.00M1.1%
Portfolio Concentration
Top 3$581.34M94.9%
4–10$31.51M5.1%
Top 3 weight
94.9%
Top 10 weight
100.0%
Voting Authority Distribution
Total shares with voting rights: 38.46M
Sole
Full voting authority
38.46M
shares
% of voting shares100.0%
Shared
Joint voting authority
0.00
shares
% of voting shares0.0%
None
No voting authority
0.00
shares
% of voting shares0.0%
Investment Discretion (by position count)
Sole7
Shared0
Other0
Dominant voting typeSole · 100.0% of voting shares
Institutional Holdings7
Rows:
ATS CORPORATION
SOLEShares16.40M
TypeSH
Market value$462.60M
75.48%
Sole
16.40M
Shared
0.00
None
0.00
ENVIRI CORP
SOLEShares4.49M
TypeSH
Market value$88.18M
14.39%
Sole
4.49M
Shared
0.00
None
0.00
BROOKDALE SENIOR LIVING INC
SOLEShares2.23M
TypeSH
Market value$30.56M
4.99%
Sole
2.23M
Shared
0.00
None
0.00
CLEAR CHANNEL OUTDOOR HLDGS
SOLEShares9.83M
TypeSH
Market value$23.29M
3.80%
Sole
9.83M
Shared
0.00
None
0.00
READY CAPITAL CORP
SOLEShares4.32M
TypeSH
Market value$7.00M
1.14%
Sole
4.32M
Shared
0.00
None
0.00
JELD-WEN HOLDING INC
SOLEShares776.88K
TypeSH
Market value$963.3K
0.16%
Sole
776.88K
Shared
0.00
None
0.00
SIGNATURE BANK
SOLEShares400K
TypeSH
Market value$260.0K
0.04%
Sole
400K
Shared
0.00
None
0.00
| Issuer | Class | Shares | Type | Value / Portfolio % | Voting — Sole | Shared | None |
|---|---|---|---|---|---|---|---|
ATS CORPORATIONSOLE | COM | 16.40M | SH | $462.60M 75.48% | 16.40M | 0.00 | 0.00 |
ENVIRI CORPSOLE | COM | 4.49M | SH | $88.18M 14.39% | 4.49M | 0.00 | 0.00 |
BROOKDALE SENIOR LIVING INCSOLE | COM | 2.23M | SH | $30.56M 4.99% | 2.23M | 0.00 | 0.00 |
CLEAR CHANNEL OUTDOOR HLDGSSOLE | COM | 9.83M | SH | $23.29M 3.80% | 9.83M | 0.00 | 0.00 |
READY CAPITAL CORPSOLE | REIT | 4.32M | SH | $7.00M 1.14% | 4.32M | 0.00 | 0.00 |
JELD-WEN HOLDING INCSOLE | COM | 776.88K | SH | $963.3K 0.16% | 776.88K | 0.00 | 0.00 |
SIGNATURE BANKSOLE | COM | 400K | SH | $260.0K 0.04% | 400K | 0.00 | 0.00 |