Atrium Therapeutics, Inc.
RNA- Exchange
- Nasdaq
- Industry
- Pharmaceutical Preparations
- SEC CIK
- 0002093101
No open-market purchases or sales by Atrium Therapeutics, Inc. insiders were filed in the last 90 days; 154 institutions reported holding it in 13F filings for Q2 2026, worth $192.8M in total; no superinvestor holds it.
13F holders, Q1 2026
Institutional positions in Atrium Therapeutics, Inc. as of Mar 31, 2026. 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
- Institutional holders
- 163
- +163 vs. Q4 2025
- Shares held
- 14.8M
- +14.8M vs. Q4 2025
- Total value
- $198.3M
- +$198.3M vs. Q4 2025
- New holders
- 163
- 0 more added
- Sold out
- 0
- 0 more reduced
Compare with Q4 2025: new holders, sold out and not filed yet
Holders and value by quarter
Institutions reporting RNA 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 | 154 | $192.8M |
| Q1 2026 | 163 | $198.3M |
| Q4 2025 | 0 | $0 |
| Q3 2025 | 0 | $0 |
| Q2 2025 | 0 | $0 |
| Q1 2025 | 0 | $0 |
| Q4 2024 | 0 | $0 |
| Q3 2024 | 0 | $0 |
| Q2 2024 | 0 | $0 |
| Q1 2024 | 0 | $0 |
| Q4 2023 | 0 | $0 |
| Q3 2023 | 0 | $0 |
| Q2 2023 | 0 | $0 |
| Q1 2023 | 0 | $0 |
| Q4 2022 | 0 | $0 |
| Q3 2022 | 0 | $0 |
| Q2 2022 | 0 | $0 |
| Q1 2022 | 0 | $0 |
| Q4 2021 | 0 | $0 |
| Q3 2021 | 0 | $0 |
| Q2 2021 | 0 | $0 |
| Q1 2021 | 0 | $0 |
Institutions, Q1 2026
Shares, value and share of portfolio for each institution holding Atrium Therapeutics, Inc.; share changes are against Q4 2025.
| Institution | Shares | Value | % of portfolio | Change in shares | Action |
|---|---|---|---|---|---|
| Royal Bank of Canada | 35,698 | $477.0K | 0.00% | +35,698 | New |
| Fifth Lane Capital, LP | 35,999 | $481.3K | 0.58% | +35,999 | New |
| Saba Capital Management, L.P. | 39,640 | $530.0K | 0.02% | +39,640 | New |
| Highbridge Capital Management LLC | 40,986 | $555.4K | 0.04% | +40,986 | New |
| Canada Pension Plan Investment Board | 41,970 | $561.1K | 0.00% | +41,970 | New |
| Bank of New York Mellon Corp | 43,697 | $584.2K | 0.00% | +43,697 | New |
| Alethea Capital Management, LLC | 43,758 | $585.0K | 0.31% | +43,758 | New |
| Caxton Associates LLP | 44,230 | $591.4K | 0.01% | +44,230 | New |
| Oddo BHF Asset Management SAS | 45,090 | $602.9K | 0.02% | +45,090 | New |
| UBS Group AG | 49,814 | $666.0K | 0.00% | +49,814 | New |
| Twin Securities, Inc. | 49,913 | $667.3K | 0.33% | +49,913 | New |
| AWM Investment Company, Inc. | 50,000 | $668.5K | 0.07% | +50,000 | New |
| Westchester Capital Management, LLC | 55,236 | $738.5K | 0.04% | +55,236 | New |
| ADAR1 Capital Management, LLC | 57,688 | $771.0K | 0.05% | +57,688 | New |
| Manufacturers Life Insurance Company, The | 62,379 | $834.0K | 0.00% | +62,379 | New |
| Quarry LP | 66,651 | $891.1K | 0.18% | +66,651 | New |
| Neuberger Berman Group LLC | 69,294 | $926.5K | 0.00% | +69,294 | New |
| Polar Asset Management Partners Inc. | 70,000 | $935.9K | 0.02% | +70,000 | New |
| Tudor Investment Corp Et Al | 71,359 | $954.1K | 0.01% | +71,359 | New |
| ExodusPoint Capital Management, LP | 77,442 | $1.04M | 0.01% | +77,442 | New |
| FIL Ltd | 78,500 | $1.05M | 0.00% | +78,500 | New |
| Vanguard Fiduciary Trust Co | 95,128 | $1.27M | 0.00% | +95,128 | New |
| Northern Trust Corp | 98,585 | $1.32M | 0.00% | +98,585 | New |
| Caption Management, LLC | 103,592 | $1.39M | 0.07% | +103,592 | New |
| Athos Capital Ltd | 107,965 | $1.44M | 0.45% | +107,965 | New |
| Citadel Advisors LLC | 109,936 | $1.47M | 0.00% | +109,936 | New |
| TD Asset Management Inc | 111,200 | $1.49M | 0.00% | +111,200 | New |
| Charles Schwab Investment Management Inc | 116,598 | $1.56M | 0.00% | +116,598 | New |
| Creek Drive Management Group LLC | 120,000 | $1.60M | 1.01% | +120,000 | New |
| Yakira Capital Management, Inc. | 126,645 | $1.69M | 0.50% | +126,645 | New |
| Bank of America Corp | 136,248 | $1.82M | 0.00% | +136,248 | New |
| Nomura Holdings Inc | 137,380 | $1.84M | 0.02% | +137,380 | New |
| Bracebridge Capital, LLC | 139,239 | $1.86M | 0.33% | +139,239 | New |
| Janus Henderson Group PLC | 139,973 | $1.87M | 0.00% | +139,973 | New |
| Marble Bar Asset Management LLP | 147,000 | $1.97M | 1.93% | +147,000 | New |
| Highland Capital Management Fund Advisors, L.P. | 150,025 | $2.01M | 0.14% | +150,025 | New |
| Schonfeld Strategic Advisors LLC | 162,759 | $2.18M | 0.02% | +162,759 | New |
| Morgan Stanley | 165,036 | $2.21M | 0.00% | +165,036 | New |
| Two Sigma Investments, LP | 178,560 | $2.39M | 0.00% | +178,560 | New |
| CNH Partners LLC | 179,713 | $2.40M | 0.04% | +179,713 | New |
| Slotnik Capital, LLC | 180,945 | $2.42M | 0.72% | +180,945 | New |
| Adage Capital Partners GP, L.L.C. | 183,580 | $2.45M | 0.00% | +183,580 | New |
| Millennium Management LLC | 190,859 | $2.55M | 0.00% | +190,859 | New |
| Arbiter Partners Capital Management LLC | 230,000 | $3.08M | 2.09% | +230,000 | New |
| Squarepoint Ops LLC | 231,466 | $3.09M | 0.01% | +231,466 | New |
| Balyasny Asset Management LLC | 235,115 | $3.14M | 0.01% | +235,115 | New |
| Cantor Fitzgerald, L. P. | 235,637 | $3.15M | 0.11% | +235,637 | New |
| Weiss Asset Management LP | 240,701 | $3.22M | 0.06% | +240,701 | New |
| State Street Corp | 257,086 | $3.44M | 0.00% | +257,086 | New |
| Bellevue Group AG | 263,096 | $3.52M | 0.08% | +263,096 | New |
| 683 Capital Management, LLC | 300,000 | $4.01M | 0.37% | +300,000 | New |
| Geode Capital Management, LLC | 319,831 | $4.28M | 0.00% | +319,831 | New |
| Vanguard Portfolio Management LLC | 344,369 | $4.60M | 0.00% | +344,369 | New |
| Farallon Capital Management, L.L.C. | 349,360 | $4.67M | 0.03% | +349,360 | New |
| Goldman Sachs Group Inc | 349,950 | $4.68M | 0.00% | +349,950 | New |
| Sessa Capital IM, L.P. | 551,391 | $7.37M | 0.14% | +551,391 | New |
| O'Connor Alternative Investments LLC | 578,011 | $7.73M | 0.41% | +578,011 | New |
| Pentwater Capital Management LP | 602,649 | $8.06M | 0.06% | +602,649 | New |
| TIG Advisors, LLC | 607,552 | $8.12M | 0.39% | +607,552 | New |
| Vanguard Capital Management LLC | 626,869 | $8.38M | 0.00% | +626,869 | New |
| Ra Capital Management, L.P. | 864,102 | $11.6M | 0.12% | +864,102 | New |
| BlackRock, Inc. | 1,205,291 | $16.1M | 0.00% | +1,205,291 | New |
| Price T Rowe Associates Inc | 1,553,210 | $20.8M | 0.00% | +1,553,210 | New |