Merrimack Pharmaceuticals Inc
MACKDelisted- Industry
- Pharmaceutical Preparations
- SEC CIK
- 0001274792
Merrimack Pharmaceuticals Inc was delisted in 2024; its insiders filed their last Form 4 on Dec 28, 2023; 70 institutions reported holding it in 13F filings for Q1 2024, worth $138.5M in total; no superinvestor held it.
13F holders, Q2 2025
Institutional positions in Merrimack Pharmaceuticals Inc as of Jun 30, 2025. Investment managers with $100 million or more in US stocks report their long positions on Form 13F within 45 days after each quarter ends. How 13F works
MACK is no longer listed, and 13F filings after Q1 2024 list far fewer holders. See Q1 2024
- Institutional holders
- 1
- 0 vs. Q1 2025
- Shares held
- 24.5K
- 0 (0.0%) vs. Q1 2025
- Total value
- $0
- $0 vs. Q1 2025
- New holders
- 0
- 0 more added
- Sold out
- 0
- 0 more reduced
Compare with Q1 2025: new holders, sold out and not filed yet
Holders and value by quarter
Institutions reporting MACK on Form 13F each quarter since Q1 2021, and the total value they reported. Values are as of each quarter end, so they also move with the share price.
| Quarter | Holders | Value |
|---|---|---|
| Q2 2026 | 1 | $0 |
| Q1 2026 | 1 | $0 |
| Q4 2025 | 1 | $0 |
| Q3 2025 | 1 | $0 |
| Q2 2025 | 1 | $0 |
| Q1 2025 | 1 | $0 |
| Q4 2024 | 2 | $370.7K |
| Q3 2024 | 2 | $0 |
| Q2 2024 | 12 | $5.32M |
| Q1 2024 | 70 | $138.5M |
| Q4 2023 | 67 | $126.4M |
| Q3 2023 | 63 | $104.4M |
| Q2 2023 | 62 | $98.5M |
| Q1 2023 | 50 | $91.0M |
| Q4 2022 | 47 | $86.6M |
| Q3 2022 | 41 | $30.0M |
| Q2 2022 | 42 | $48.0M |
| Q1 2022 | 40 | $49.4M |
| Q4 2021 | 37 | $29.4M |
| Q3 2021 | 38 | $37.1M |
| Q2 2021 | 42 | $50.3M |
| Q1 2021 | 43 | $49.8M |
Institutions, Q2 2025
Shares, value and share of portfolio for each institution holding Merrimack Pharmaceuticals Inc; share changes are against Q1 2025.
| Institution | Shares | Value | % of portfolio | Change in shares | Action |
|---|---|---|---|---|---|
| Massmutual Trust Co FSB | 24,500 | $0 | 0.00% | 00.0% | Unchanged |