Mersana Therapeutics, Inc.
MRSNDelisted Jan 6, 2026- Industry
- Pharmaceutical Preparations
- SEC CIK
- 0001442836
Mersana Therapeutics, Inc. was delisted on Jan 6, 2026; its insiders filed their last Form 4 on Jan 6, 2026; 51 institutions reported holding it in 13F filings for Q4 2025, worth $64.8M in total; no superinvestor held it.
13F holders, Q1 2026
Institutional positions in Mersana 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
MRSN is no longer listed, and 13F filings after Q4 2025 list far fewer holders. See Q4 2025
- Institutional holders
- 1
- −49 vs. Q4 2025
- Shares held
- 3
- −2.03M (−100.0%) vs. Q4 2025
- Total value
- $87
- −$58.7M (−100.0%) vs. Q4 2025
- New holders
- 0
- 0 more added
- Sold out
- 49
- 0 more reduced
1 institution that held it in Q4 2025 haven't filed for Q1 2026 yet. Not filing isn't selling, so they aren't counted as sold out or in the changes above.
Compare with Q4 2025: new holders, sold out and not filed yet
Holders and value by quarter
Institutions reporting MRSN 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 | 0 | $0 |
| Q1 2026 | 1 | $87 |
| Q4 2025 | 51 | $64.8M |
| Q3 2025 | 49 | $24.7M |
| Q2 2025 | 85 | $22.9M |
| Q1 2025 | 111 | $30.2M |
| Q4 2024 | 132 | $149.2M |
| Q3 2024 | 116 | $219.4M |
| Q2 2024 | 122 | $229.6M |
| Q1 2024 | 125 | $526.3M |
| Q4 2023 | 106 | $263.0M |
| Q3 2023 | 128 | $144.4M |
| Q2 2023 | 147 | $370.2M |
| Q1 2023 | 158 | $437.2M |
| Q4 2022 | 152 | $592.8M |
| Q3 2022 | 152 | $623.4M |
| Q2 2022 | 126 | $408.0M |
| Q1 2022 | 128 | $322.7M |
| Q4 2021 | 122 | $436.6M |
| Q3 2021 | 110 | $648.3M |
| Q2 2021 | 131 | $957.8M |
| Q1 2021 | 132 | $1.14B |
Institutions, Q1 2026
Shares, value and share of portfolio for each institution holding Mersana Therapeutics, Inc.; share changes are against Q4 2025.
| Institution | Shares | Value | % of portfolio | Change in shares | Action |
|---|---|---|---|---|---|
| IFP Advisors, Inc | 3 | $87 | 0.00% | 00.0% | Unchanged |
| Nextech Invest, Ltd. | 0 | $0 | 0.00% | −482,689−100.0% | Sold out |
| Bain Capital Life Sciences Investors, LLC | 0 | $0 | 0.00% | −346,545−100.0% | Sold out |
| Rock Springs Capital Management LP | 0 | $0 | 0.00% | −152,586−100.0% | Sold out |
| Alamea Verwaltungs GmbH | 0 | $0 | 0.00% | −24,165−100.0% | Sold out |
| Acadian Asset Management LLC | 0 | $0 | 0.00% | −110,882−100.0% | Sold out |
| Affinity Asset Advisors, LLC | 0 | $0 | 0.00% | −100,000−100.0% | Sold out |
| BlackRock, Inc. | 0 | $0 | 0.00% | −69,210−100.0% | Sold out |
| Bank of America Corp | 0 | $0 | 0.00% | −65,749−100.0% | Sold out |
| Millennium Management LLC | 0 | $0 | 0.00% | −63,305−100.0% | Sold out |
| Groupe la Francaise | 0 | $0 | 0.00% | −61,488−100.0% | Sold out |
| Rangeley Capital, LLC | 0 | $0 | 0.00% | −57,098−100.0% | Sold out |
| Gabelli Funds LLC | 0 | $0 | 0.00% | −47,300−100.0% | Sold out |
| Geode Capital Management, LLC | 0 | $0 | 0.00% | −43,920−100.0% | Sold out |
| Credit Industriel Et Commercial | 0 | $0 | 0.00% | −41,392−100.0% | Sold out |
| AQR Capital Management LLC | 0 | $0 | 0.00% | −37,264−100.0% | Sold out |
| Mackenzie Financial Corp | 0 | $0 | 0.00% | −33,834−100.0% | Sold out |
| Yakira Capital Management, Inc. | 0 | $0 | 0.00% | −32,663−100.0% | Sold out |
| Citadel Advisors LLC | 0 | $0 | 0.00% | −22,493−100.0% | Sold out |
| State Street Corp | 0 | $0 | 0.00% | −19,543−100.0% | Sold out |
| Morgan Stanley | 0 | $0 | 0.00% | −18,496−100.0% | Sold out |
| Deltec Asset Management LLC | 0 | $0 | 0.00% | −18,000−100.0% | Sold out |
| Knott David M Jr | 0 | $0 | 0.00% | −111,686−100.0% | Sold out |
| Ieq Capital, LLC | 0 | $0 | 0.00% | −12,955−100.0% | Sold out |
| XTX Topco Ltd | 0 | $0 | 0.00% | −11,948−100.0% | Sold out |
| Point72 Asset Management, L.P. | 0 | $0 | 0.00% | −10,364−100.0% | Sold out |
| Gamco Investors, Inc. Et Al | 0 | $0 | 0.00% | −10,000−100.0% | Sold out |
| Northern Trust Corp | 0 | $0 | 0.00% | −8,586−100.0% | Sold out |
| Omers Administration Corp | 0 | $0 | 0.00% | −7,900−100.0% | Sold out |
| Equitec Proprietary Markets, LLC | 0 | $0 | 0.00% | −5,593−100.0% | Sold out |
| CWM, LLC | 0 | $0 | 0.00% | −2,286−100.0% | Sold out |
| BNP Paribas Arbitrage, SA | 0 | $0 | 0.00% | −1,090−100.0% | Sold out |
| Group One Trading, L.P. | 0 | $0 | 0.00% | −1,073−100.0% | Sold out |
| Mint Tower Capital Management B.V. | 0 | $0 | 0.00% | −1,035−100.0% | Sold out |
| Tower Research Capital LLC (TRC) | 0 | $0 | 0.00% | −376−100.0% | Sold out |
| UBS Group AG | 0 | $0 | 0.00% | −221−100.0% | Sold out |
| Royal Bank of Canada | 0 | $0 | 0.00% | −168−100.0% | Sold out |
| JPMorgan Chase & Co | 0 | $0 | 0.00% | −112−100.0% | Sold out |
| Advisor Group Holdings, Inc. | 0 | $0 | 0.00% | −103−100.0% | Sold out |
| Lion Point Capital, LP | 0 | $0 | 0.00% | −100−100.0% | Sold out |
| Essential Partners LLC | 0 | $0 | 0.00% | −82−100.0% | Sold out |
| Flagship Harbor Advisors, LLC | 0 | $0 | 0.00% | −76−100.0% | Sold out |
| SBI Securities Co., Ltd. | 0 | $0 | 0.00% | −53−100.0% | Sold out |
| Wells Fargo & Company | 0 | $0 | 0.00% | −40−100.0% | Sold out |
| Huntington National Bank | 0 | $0 | 0.00% | −32−100.0% | Sold out |
| SHP Wealth Management | 0 | $0 | 0.00% | −25−100.0% | Sold out |
| EverSource Wealth Advisors, LLC | 0 | $0 | 0.00% | −11−100.0% | Sold out |
| FMR LLC | 0 | $0 | 0.00% | −8−100.0% | Sold out |
| North Star Investment Management Corp. | 0 | $0 | 0.00% | −6−100.0% | Sold out |
| Danske Bank A/S | 0 | $0 | 0.00% | −1−100.0% | Sold out |
| Vanguard Group Inc | – | – | – | – | Not filed |