MASON CAPITAL MANAGEMENT LLC
NEW YORK, NY · CIK 1218735 · 13F filing filed 2023-08-14
SEC-registered investment adviser since 2012 · limited liability company
- Assets managed$2.2bn
- Staff15 · 10 in investment roles
- Main clients (by assets)Private funds 100%
- Private funds3 (2 hedge) · $2.8bn gross assets
- Websitemasoncap.com
- Form ADV · 2026-03-31SEC adviser record
- Legal entityMASON CAPITAL MANAGEMENT LLC (US)
$1.0bn
reported value
+338.3% vs Q1 2023
10positions
100.0%in top 10
5 new
0 added
4 reduced
7 sold out
vs Q1 2023
Holdings, Q2 2023
The small lines show how much was held over the last 4 quarters (adjusted for stock splits).
| Security | Value | Change |
|---|---|---|
| ATS CORPORATION ATS | $822.7m80.16% | New |
| VMWARE INC VMW | $55.6m5.42% | New |
| ACTIVISION BLIZZARD INC ATVI | $44.4m4.33% | New |
| CLEAR CHANNEL OUTDOOR HLDGS CCO | $29.1m2.84% | Unchanged |
| SELECT SECTOR SPDR TR XLI | $25.5m2.48% | Reduced -44.0k |
| GAMESTOP CORP NEW GME | $16.6m1.62% | Reduced -72.6k |
| TECK RESOURCES LTD TECK | $14.9m1.45% | New |
| COLOMBIER ACQUISITION CORP CL A | $13.3m1.29% | New |
| SEADRILL LTD SDRL | $4.0m0.39% | Reduced -73.2k |
| FORWARD PHARMA A/S SPONSORD ADS NEW | $300.0k0.03% | Reduced -149.7k |
Sold out since Q1 2023
| Security | Value then |
|---|---|
| GEO GROUP INC NEW GEO | $42.6m5.4m shares |
| WEATHERFORD INTL PLC WFRD | $39.2m660.5k shares |
| MADISON SQUARE GRDN SPRT COR MSGS | $27.6m141.6k shares |
| ALIBABA GROUP HLDG LTD BABA | $17.1m167.0k shares |
| NEWS CORP NEW NWSA | $14.3m828.6k shares |
| TRANSOCEAN LTD RIG | $5.7m898.0k shares |
| EURONAV NV CMBT | $5.3m317.0k shares |
Stakes above 5%
Companies where this manager has reported owning more than 5% of a class of shares, on Schedule 13D (may seek influence) or 13G (passive): its latest filing for each, from 19 Dec 2024 on.
| Company | Stake |
|---|---|
| VERADIGM INC MDRX · 13G · filed 2026-01-29 | 5.8% |
| JELD-WEN HLDG INC JELD · 13G · filed 2026-08-05 | 5.5%≈ $7.2m |