Skip to main content

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, Q4 2024

Institutional positions in Mersana Therapeutics, Inc. as of Dec 31, 2024. 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
132
+18 vs. Q3 2024
Shares held
104.3M
−11.3M (−9.7%) vs. Q3 2024
Total value
$149.2M
−$69.2M (−31.7%) vs. Q3 2024
New holders
30
33 more added
Sold out
12
40 more reduced

2 institutions that held it in Q3 2024 haven't filed for Q4 2024 yet. Not filing isn't selling, so they aren't counted as sold out or in the changes above.

Compare with Q3 2024: 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.

Institutional holdersQ4 2024: 132 institutions
Q1 2021: 132 institutionsQ2 2021: 131 institutionsQ3 2021: 110 institutionsQ4 2021: 122 institutionsQ1 2022: 128 institutionsQ2 2022: 126 institutionsQ3 2022: 152 institutionsQ4 2022: 152 institutionsQ1 2023: 158 institutionsQ2 2023: 147 institutionsQ3 2023: 128 institutionsQ4 2023: 106 institutionsQ1 2024: 125 institutionsQ2 2024: 122 institutionsQ3 2024: 116 institutionsQ4 2024: 132 institutionsQ1 2025: 111 institutionsQ2 2025: 85 institutionsQ3 2025: 49 institutionsQ4 2025: 51 institutionsQ1 2026: 1 institutionQ2 2026: 0 institutions
Value heldQ4 2024: $149.2M
Q1 2021: $1.14BQ2 2021: $957.8MQ3 2021: $648.3MQ4 2021: $436.6MQ1 2022: $322.7MQ2 2022: $408.0MQ3 2022: $623.4MQ4 2022: $592.8MQ1 2023: $437.2MQ2 2023: $370.2MQ3 2023: $144.4MQ4 2023: $263.0MQ1 2024: $526.3MQ2 2024: $229.6MQ3 2024: $219.4MQ4 2024: $149.2MQ1 2025: $30.2MQ2 2025: $22.9MQ3 2025: $24.7MQ4 2025: $64.8MQ1 2026: $87Q2 2026: $0
Institutions holding MRSN and their total value by quarter
QuarterHoldersValue
Q2 20260$0
Q1 20261$87
Q4 202551$64.8M
Q3 202549$24.7M
Q2 202585$22.9M
Q1 2025111$30.2M
Q4 2024132$149.2M
Q3 2024116$219.4M
Q2 2024122$229.6M
Q1 2024125$526.3M
Q4 2023106$263.0M
Q3 2023128$144.4M
Q2 2023147$370.2M
Q1 2023158$437.2M
Q4 2022152$592.8M
Q3 2022152$623.4M
Q2 2022126$408.0M
Q1 2022128$322.7M
Q4 2021122$436.6M
Q3 2021110$648.3M
Q2 2021131$957.8M
Q1 2021132$1.14B

Institutions, Q4 2024

Shares, value and share of portfolio for each institution holding Mersana Therapeutics, Inc.; share changes are against Q3 2024.

Institutions holding MRSN in Q4 2024
InstitutionSharesValue% of portfolioChange in sharesAction
Nextech Invest AG12,067,246$17.3M2.80%00.0%Unchanged
EcoR1 Capital, LLC11,328,000$16.2M0.65%−8,036,688−41.5%Reduced
VR Adviser, LLC10,257,790$14.7M1.01%−1,070,210−9.4%Reduced
BlackRock, Inc.9,205,182$13.2M0.00%+583,321+6.8%Added
Bain Capital Life Sciences Investors, LLC8,663,673$12.4M1.46%00.0%Unchanged
Vanguard Group Inc7,057,516$10.1M0.00%−119,942−1.7%Reduced
Novo Holdings A/S4,250,000$6.08M0.37%+4,250,000New
Rock Springs Capital Management LP3,431,684$4.91M0.19%+384,902+12.6%Added
State Street Corp2,764,895$3.95M0.00%+39,501+1.4%Added
Boxer Capital Management, LLC2,635,000$3.77M0.32%+2,635,000New
JPMorgan Chase & Co2,534,447$3.62M0.00%+183,088+7.8%Added
Geode Capital Management, LLC2,442,250$3.49M0.00%+29,035+1.2%Added
Schonfeld Strategic Advisors LLC2,119,586$3.03M0.02%−103,722−4.7%Reduced
Catalio Capital Management, LP1,705,036$2.44M0.53%+1,705,036New
5AM Venture Management, LLC1,305,000$1.87M0.45%00.0%Unchanged
Morgan Stanley1,203,356$1.72M0.00%−160,860−11.8%Reduced
Acuta Capital Partners, LLC1,120,500$1.60M1.61%−79,500−6.6%Reduced
Jacobs Levy Equity Management, Inc1,111,998$1.59M0.01%+118,952+12.0%Added
Baker Bros. Advisors LP1,086,115$1.55M0.02%00.0%Unchanged
Octagon Capital Advisors LP992,000$1.42M0.24%00.0%Unchanged
Bank of America Corp953,952$1.36M0.00%−36,084−3.6%Reduced
Northern Trust Corp929,708$1.33M0.00%−3,783−0.4%Reduced
683 Capital Management, LLC900,000$1.29M0.13%+717,207+392.4%Added
Deutsche Bank AG839,724$1.20M0.00%−756,449−47.4%Reduced
Goldman Sachs Group Inc802,366$1.15M0.00%−1,156,870−59.0%Reduced
Millennium Management LLC795,973$1.14M0.00%+536,190+206.4%Added
Sphera Funds Management Ltd.690,272$987.1K0.18%+690,272New
Renaissance Technologies LLC606,285$867.0K0.00%+113,566+23.0%Added
Wellington Management Group LLP576,148$823.9K0.00%−42,157−6.8%Reduced
D. E. Shaw & Co., Inc.544,463$778.6K0.00%−477,992−46.7%Reduced
HealthInvest Partners AB538,621$764.8K0.36%00.0%Unchanged
Gsa Capital Partners LLP508,296$727.0K0.05%+236,522+87.0%Added
Two Sigma Advisers, LP448,000$640.6K0.00%−38,800−8.0%Reduced
Woodline Partners LP435,593$622.9K0.00%+2,041+0.5%Added
Citadel Advisors LLC421,360$602.5K0.00%−3,990,195−90.4%Reduced
UBS Oconnor LLC410,029$586.3K0.01%−160,000−28.1%Reduced
BNP Paribas Arbitrage, SA361,147$516.4K0.00%+123,949+52.3%Added
Qube Research & Technologies Ltd347,415$496.8K0.00%−529,628−60.4%Reduced
Bank of New York Mellon Corp346,189$495.1K0.00%−25,984−7.0%Reduced
Verition Fund Management LLC336,806$481.6K0.00%−966,443−74.2%Reduced
Charles Schwab Investment Management Inc312,623$447.1K0.00%00.0%Unchanged
FMR LLC299,324$428.0K0.00%+21,584+7.8%Added
Panagora Asset Management Inc239,685$342.8K0.00%+6,476+2.8%Added
Nuveen Asset Management, LLC232,223$332.1K0.00%+81,022+53.6%Added
Two Sigma Investments, LP210,876$301.6K0.00%−89,346−29.8%Reduced
ExodusPoint Capital Management, LP194,153$278.0K0.00%+194,153New
Alliancebernstein L.P.186,060$266.1K0.00%00.0%Unchanged
Federated Hermes, Inc.183,723$262.7K0.00%−210.0%Reduced
Barclays PLC182,711$261.3K0.00%−311,805−63.1%Reduced
Exome Asset Management LLC172,924$249.7K0.19%−1,005,646−85.3%Reduced
Rhumbline Advisers171,857$245.7K0.00%+5,011+3.0%Added
UBS Group AG162,264$232.0K0.00%−311,263−65.7%Reduced
Los Angeles Capital Management LLC159,760$228.5K0.00%−29,900−15.8%Reduced
Jane Street Group, LLC151,526$216.7K0.00%−265,925−63.7%Reduced
Macquarie Group Ltd150,000$215.0K0.00%00.0%Unchanged
SG Americas Securities, LLC112,291$161.0K0.00%+25,058+28.7%Added
Citigroup Inc97,831$139.9K0.00%+15,519+18.9%Added
Mackenzie Financial Corp91,956$131.5K0.00%+91,956New
Susquehanna Fundamental Investments, LLC91,852$131.3K0.00%+91,852New
Exchange Traded Concepts, LLC85,006$121.6K0.00%00.0%Unchanged
MetLife Investment Management73,150$104.6K0.00%+39,234+115.7%Added
SEI Investments Co69,527$99.4K0.00%+69,527New
Wells Fargo & Company67,483$96.5K0.00%+19,368+40.3%Added
Mirae Asset Global ETFs Holdings Ltd.65,936$94.3K0.00%+2,812+4.5%Added
Oxford Asset Management LLP65,386$93.5K0.04%+65,386New
XTX Topco Ltd63,530$90.8K0.01%−283,725−81.7%Reduced
QVT Financial LP62,657$89.6K0.01%00.0%Unchanged
Price T Rowe Associates Inc62,093$89.0K0.00%−36,985−37.3%Reduced
Algert Global LLC60,083$85.9K0.00%−3,400−5.4%Reduced
Corebridge Financial, Inc.56,398$80.6K0.00%−4,257−7.0%Reduced
Avanza Fonder AB56,298$80.5K0.00%+56,298New
Invesco Ltd.54,872$78.5K0.00%−611−1.1%Reduced
Ameriprise Financial Inc53,329$76.3K0.00%+7,682+16.8%Added
Group One Trading, L.P.52,283$74.8K0.00%+19,713+60.5%Added
Prelude Capital Management, LLC51,357$73.4K0.01%−313,370−85.9%Reduced
Intech Investment Management LLC51,028$73.0K0.00%+23,686+86.6%Added
Susquehanna International Group, LLP49,853$71.3K0.00%−24,956−33.4%Reduced
Graham Capital Management, L.P.49,724$71.1K0.00%+7,307+17.2%Added
Cubist Systematic Strategies, LLC45,296$64.8K0.00%+45,296New
Manufacturers Life Insurance Company, The43,990$62.9K0.00%−483−1.1%Reduced
ProShare Advisors LLC37,799$54.1K0.00%+16,364+76.3%Added
New York State Common Retirement Fund37,235$53.2K0.00%00.0%Unchanged
Voya Investment Management LLC36,190$51.8K0.00%−2,111−5.5%Reduced
Walleye Trading LLC31,526$45.1K0.00%00.0%Unchanged
State Board of Administration of Florida Retirement System28,800$41.2K0.00%00.0%Unchanged
Atom Investors LP26,563$38.0K0.00%+1,902+7.7%Added
China Universal Asset Management Co., Ltd.26,194$37.5K0.00%+26,194New
Quarry LP24,000$34.3K0.01%−6,000−20.0%Reduced
Jasper Ridge Partners, L.P.23,100$33.0K0.00%00.0%Unchanged
Police & Firemen's Retirement System of New Jersey22,593$32.3K0.00%+22,593New
Public Employees Retirement System of Ohio20,587$29.4K0.00%00.0%Unchanged
Engineers Gate Manager LP17,084$24.4K0.00%+17,084New
US Bancorp16,178$23.1K0.00%00.0%Unchanged
Marshall Wace, LLP15,600$22.3K0.00%+15,600New
Grimes & Company, Inc.14,998$21.4K0.00%00.0%Unchanged
Aquatic Capital Management LLC14,551$20.8K0.00%+14,551New
HSBC Holdings PLC13,301$18.3K0.00%−664−4.8%Reduced
Bayesian Capital Management, LP12,600$18.0K0.00%+12,600New
Squarepoint Ops LLC12,104$17.3K0.00%−69,525−85.2%Reduced
Lazard Asset Management LLC12,104$17.0K0.00%+12,104New