MASON CAPITAL MANAGEMENT LLC — 13F Holdings

2026 Q2  ·  9 Positions

2026 Q2 Portfolio Activity

In 2026 Q2, MASON CAPITAL MANAGEMENT LLC maintained a portfolio of 9 distinct positions. The most significant new addition was GROUPON INC, now representing 2.60% of the total fund value. They heavily accumulated shares in BROOKDALE SENIOR LIVING INC, increasing the position by 15.3%. The fund also reduced its exposure to ENVIRI CORP by 60.6%.
Position History hover any row below to update
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PCA Score Concentration Risk
Risk ENB
Total Positions
9
Quarter
2026 Q2
Top Holding
ATS (77.8%)
Top 10 Concentration
100.0%
Turnover Rate
23.4%
Sector HHI
0.18
Items per page:
Showing 1-9 of 9

MASON CAPITAL MANAGEMENT LLC Full Holdings List — 2026 Q2

Stock History Sector / Type Port % Prev % Rank / Prev Conviction
Freshness
Change % Change Influence Shares Mkt Value Avg Cost Price Held 1st Owned Source Source Date Date Reported
ATS
ATS CORPORATION
Industrials 77.78% 75.48% #1
Prev: #1
7.0
no change no change
P
S
16,404,170 $472,112,013 2023 Q2 13F Filing 2026-06-30 2026-08-14
BKD
BROOKDALE SENIO...
Healthcare 6.83% 4.99% #2 1
Prev: #3
6.2
342,085 15.3%
P
S
2,575,826 $41,445,040 2025 Q3 13F Filing 2026-06-30 2026-08-14
NVRI
ENVIRI CORP
Industrials 6.40% 14.39% #3 1
Prev: #2
3.6
-2,723,577 -60.6%
P
S
1,770,959 $38,872,550 2026 Q1 13F Filing 2026-06-30 2026-08-14
CCO
CLEAR CHANNEL O...
Communication Services 3.92% 3.80% #4
Prev: #4
3.1
no change no change
P
S
9,828,401 $23,784,730 2019 Q2 13F Filing 2026-06-30 2026-08-14
GRPN
GROUPON INC
Communication Services 2.60% #5
Prev: #—
5.0
657,144
NEW
657,144 $15,810,885 2026 Q2 13F Filing 2026-06-30 2026-08-14
RC
READY CAPITAL C...
Real Estate 1.25% 1.14% #6 1
Prev: #5
1.5
no change no change
P
S
4,319,933 $7,559,883 2024 Q3 13F Filing 2026-06-30 2026-08-14
JELD
JELD-WEN HOLDIN...
Industrials 0.77% 0.16% #7 1
Prev: #6
3.3
2,332,736 300.3%
P
S
3,109,621 $4,664,432 2026 Q1 13F Filing 2026-06-30 2026-08-14
LOGCD
CONTEXTLOGIC HO...
Unknown 0.43% #8
Prev: #—
3.7
291,341
NEW
291,341 $2,592,935 2026 Q2 13F Filing 2026-06-30 2026-08-14
SBNY
SIGNATURE BANK
Financial Services 0.03% 0.04% #9 2
Prev: #7
1.0
no change no change
P
S
400,000 $180,000 2024 Q1 13F Filing 2026-06-30 2026-08-14
Showing 1-9 of 9 holdings

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