Merrimack PharmaceuticalsMACK
13F holders, Q1 2024 (March 31)70holders
2famous investors
$14.77avg. 13F price*
At the end of Q1 2024, 70 institutions reported holding Merrimack Pharmaceuticals Inc. (MACK) in their 13F filings. The largest holders were Western Standard LLC ($32.1M), Newtyn Management, LLC ($27.7M) and ADAR1 Capital Management, LLC ($13.3M). 2 famous investors held it, including Jim Simons / Peter Brown (0.0% of Renaissance Technologies's portfolio) and Ken Griffin (0.0% of Citadel Advisors's portfolio).
- Company
- Merrimack Pharmaceuticals Inc.
- CUSIP
- 590328209
- Latest filing quarter
- Q2 2026
History
Number of 13F holders
Total Exit/New Position Q1 2024
| Institutions | Total Value | |
|---|---|---|
| New Positions | 12 | $985K |
| Exits | 9 | $8.5M |
Ownership 70 holders
| Western Standard LLC | 30.25% | No change | 2,172,513 | $32.1M |
| Newtyn Management, LLC | 5.57% | No change | 1,873,694 | $27.7M |
| ADAR1 Capital Management, LLC | 3.64% | Add +64.2% | 902,350 | $13.3M |
| BlackRock Inc. | 0.00% | Reduce -2.7% | 723,294 | $10.7M |
| Vanguard Group Inc. | 0.00% | Add +1.9% | 620,847 | $9.2M |
| Dimensional Fund Advisors LP | 0.00% | Reduce -8.6% | 398,001 | $5.9M |
| Madison Avenue Partners, LP | 0.92% | Reduce -30.0% | 387,221 | $5.7M |
| Sepio Capital, LP | 0.38% | Reduce -2.6% | 298,545 | $4.4M |
| Invesco Ltd. | 0.00% | Add +2196.7% | 277,124 | $4.1M |
| Geode Capital Management, LLC | 0.00% | Add +4.6% | 272,015 | $4.0M |
| State Street Corp. | 0.00% | Add +25.5% | 246,853 | $3.6M |
| Wittenberg Investment Management, Inc. | 1.07% | No change | 210,239 | $3.1M |
| Renaissance Technologies | 0.00% | Add +231.7% | 162,184 | $2.4M |
| Yakira Capital Management, Inc. | 0.63% | Add +123.1% | 120,756 | $1.8M |
| Northern Trust Corp. | 0.00% | Add +0.6% | 117,548 | $1.7M |
| Bank of New York Mellon Corp | 0.00% | Reduce -5.3% | 94,895 | $1.4M |
| Susquehanna International Group, LLP | 0.00% | Reduce -4.0% | 77,397 | $1.1M |
| Morgan Stanley | 0.00% | Reduce -64.0% | 39,442 | $583K |
| Bridgeway Capital Management, LLC | 0.01% | No change | 34,200 | $505K |
| Charles Schwab Investment Management Inc. | 0.00% | No change | 29,628 | $438K |
| Two Sigma Investments, LP | 0.00% | Reduce -6.6% | 20,401 | $301K |
| STRS Ohio | 0.00% | Add +475.8% | 19,000 | $280K |
| Goldman Sachs Group Inc. | 0.00% | Reduce -58.9% | 14,471 | $214K |
| Nuveen Asset Management, LLC | 0.00% | No change | 13,719 | $203K |
| Rhumbline Advisers | 0.00% | Reduce -3.1% | 13,519 | $200K |
| Johnson Investment Counsel Inc. | 0.00% | New | 13,480 | $199K |
| UBS Group AG | 0.00% | Reduce -5.9% | 12,442 | $184K |
| JPMorgan Chase & Co. | 0.00% | Add +73.6% | 11,786 | $174K |
| Jane Street Group, LLC | 0.00% | New | 11,124 | $164K |
| Schonfeld Strategic Advisors LLC | 0.00% | New | 10,800 | $160K |
| Martingale Asset Management L P | 0.00% | New | 10,520 | $155K |
| Sherbrooke Park Advisers LLC | 0.03% | New | 10,006 | $148K |
| Aristides Capital LLC | 0.06% | New | 10,000 | $148K |
| FMR LLC | 0.00% | Reduce -7.3% | 8,263 | $122K |
| Barclays PLC | 0.00% | Reduce -48.9% | 7,348 | $109K |
| MetLife Investment Management, LLC | 0.00% | No change | 5,610 | $83K |
| American International Group, Inc. | 0.00% | Reduce -0.8% | 5,160 | $76K |
| BNP Paribas Financial Markets | 0.00% | Add +67.3% | 5,077 | $75K |
| Bank of America Corp. | 0.00% | Reduce -68.3% | 3,964 | $59K |
| Wells Fargo & Company | 0.00% | Add +15.0% | 3,211 | $47K |
| Lazard Asset Management LLC | 0.00% | No change | 2,830 | $41K |
| Citigroup Inc. | 0.00% | Add +24.4% | 1,956 | $29K |
| NewEdge Advisors, LLC | 0.00% | No change | 1,406 | $21K |
| New York State Common Retirement Fund | 0.00% | No change | 1,287 | $19K |
| Russell Investments Group, Ltd. | 0.00% | Add +4.2% | 1,111 | $16K |
| California State Teachers Retirement System | 0.00% | Reduce -38.9% | 1,053 | $16K |
| Legal & General Group Plc | 0.00% | Reduce -23.8% | 980 | $14K |
| Ameritas Investment Partners, Inc. | 0.00% | No change | 865 | $13K |
| Metropolitan Life Insurance Co | 0.00% | No change | 581 | $9K |
| Comerica Bank | 0.00% | No change | 500 | $7K |
| Citadel Advisors | 0.00% | New | 444 | $7K |
| Royal Bank of Canada | 0.00% | Reduce -87.5% | 435 | $6K |
| Deutsche Bank AG | 0.00% | Reduce -60.9% | 383 | $6K |
| Amalgamated Bank | 0.00% | Reduce -76.2% | 353 | $5K |
| Sandy Spring Bank | 0.00% | No change | 300 | $4K |
| Kayne Anderson Rudnick Investment Management LLC | 0.00% | No change | 300 | $4K |
| Tower Research Capital LLC (TRC) | 0.00% | Reduce -77.9% | 280 | $4K |
| Rise Advisors, LLC | 0.00% | No change | 272 | $4K |
| Cornerstone Planning Group LLC | 0.00% | New | 231 | $3K |
| PNC Financial Services Group, Inc. | 0.00% | Add +1962.5% | 165 | $2K |
| Covestor Ltd | 0.00% | No change | 106 | $2K |
| Tsfg, LLC | 0.00% | No change | 160 | $2K |
| POM Investment Strategies, LLC | 0.00% | New | 69 | $1K |
| Horrell Capital Management, Inc. | 0.00% | No change | 50 | $1K |
| Armstrong Advisory Group, Inc. | 0.00% | No change | 45 | $604 |
| Nisa Investment Advisors, LLC | 0.00% | No change | 15 | $222 |
| GAMMA Investing LLC | 0.00% | No change | 2 | $30 |
| Avior Wealth Management, LLC | 0.00% | New | 2 | $29 |
| Cwm, LLC | 0.00% | New | 5 | $0 |
| Capital Advisors, Ltd. LLC | 0.00% | New | 28 | $0 |
"% of holder's portfolio" is MACK's weight in each manager's 13F, not the share of Merrimack Pharmaceuticals Inc. the manager owns.