# MASON CAPITAL MANAGEMENT LLC

> Institutional holdings reported to the SEC as of Q2 2026 on Form 13F. CIK 1218735. Source: https://holderbook.com/funds/1218735-mason-capital-management-llc/

- Reported value: $607.0M
- Positions: 9
- Weight of the ten largest: 100.0%
- Filed: 2026-08-14

A 13F reports long US equity positions only. Short positions, bonds, foreign listings, private holdings and cash are not visible, so this is not the manager's whole book.

## Holdings

| Security | Ticker | Value | Shares | Weight | Quarters held |
|---|---|---|---|---|---|
| ATS CORPORATION | [ATS](https://holderbook.com/stocks/ATS/) | $472.1M | 16,404,170 | 77.8% | 13 |
| BROOKDALE SR LIVING INC | [BKD](https://holderbook.com/stocks/BKD/) | $41.4M | 2,575,826 | 6.8% | 4 |
| ENVIRI CORP | [NVRI](https://holderbook.com/stocks/NVRI/) | $38.9M | 1,770,959 | 6.4% | 2 |
| CLEAR CHANNEL OUTDOOR HLDGS | [CCO](https://holderbook.com/stocks/CCO/) | $23.8M | 9,828,401 | 3.9% | 29 |
| GROUPON INC | [GRPN](https://holderbook.com/stocks/GRPN/) | $15.8M | 657,144 | 2.6% | 1 |
| READY CAPITAL CORP | [RC](https://holderbook.com/stocks/RC/) | $7.6M | 4,319,933 | 1.2% | 3 |
| JELD-WEN HLDG INC | [JELD](https://holderbook.com/stocks/JELD/) | $4.7M | 3,109,621 | 0.8% | 2 |
| CONTEXTLOGIC HLDGS INC COM | [LOGCD](https://holderbook.com/stocks/LOGCD/) | $2.6M | 291,341 | 0.4% | 1 |
| SIGNATURE BANK | [SBNY](https://holderbook.com/stocks/SBNY/) | $180.0K | 400,000 | 0.0% | 10 |

## What the disclosed book did

Not the fund's return. This is the change in value of the positions disclosed on Form 13F, had they been left untouched, against SPY over the same quarter ends.

| Quarter | Book | Market | Difference | Priced |
|---|---|---|---|---|
| Q2 2026 | +3.9% | +14.8% | -10.9% | 100% |
| Q1 2026 | +8.3% | -4.6% | +12.9% | 100% |
| Q4 2025 | +7.4% | +2.4% | +5.0% | 100% |
| Q4 2024 | +4.4% | +2.1% | +2.3% | 100% |
| Q3 2024 | -8.6% | +5.4% | -14.0% | 100% |
| Q2 2024 | -3.1% | +4.0% | -7.1% | 77% |
| Q1 2024 | -17.3% | +10.0% | -27.4% | 100% |
| Q4 2023 | +0.7% | +11.2% | -10.5% | 100% |

## Quarter by quarter

| Quarter | Value | Positions |
|---|---|---|
| Q2 2026 | $607.0M | 9 |
| Q1 2026 | $612.9M | 7 |
| Q4 2025 | $561.6M | 9 |
| Q3 2025 | $491.4M | 6 |
| Q2 2025 | $511.5M | 4 |
| Q1 2025 | $427.2M | 5 |
| Q4 2024 | $470.5M | 4 |
| Q3 2024 | $502.6M | 6 |
| Q2 2024 | $538.2M | 6 |
| Q1 2024 | $727.8M | 6 |
| Q4 2023 | $893.9M | 7 |
| Q3 2023 | $1.2B | 8 |