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, Q2 2021

Institutional positions in Mersana Therapeutics, Inc. as of Jun 30, 2021. 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
131
−1 vs. Q1 2021
Shares held
70.6M
+496.4K (+0.7%) vs. Q1 2021
Total value
$957.8M
−$186.5M (−16.3%) vs. Q1 2021
New holders
18
51 more added
Sold out
19
40 more reduced

Compare with Q1 2021: 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 holdersQ2 2021: 131 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 heldQ2 2021: $957.8M
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, Q2 2021

Shares, value and share of portfolio for each institution holding Mersana Therapeutics, Inc.; share changes are against Q1 2021.

Institutions holding MRSN in Q2 2021
InstitutionSharesValue% of portfolioChange in sharesAction
BlackRock Inc.8,822,704$119.8M0.00%+820,618+10.3%Added
Wellington Management Group LLP6,877,336$93.4M0.02%+699,543+11.3%Added
Avoro Capital Advisors LLC6,800,000$92.3M1.61%00.0%Unchanged
Sarissa Capital Management LP4,005,600$54.4M4.33%00.0%Unchanged
Bain Capital Life Sciences Investors, LLC3,695,667$50.2M3.29%00.0%Unchanged
State Street Corp3,246,523$44.1M0.00%−499,477−13.3%Reduced
Vanguard Group Inc3,181,585$43.2M0.00%+64,216+2.1%Added
Bellevue Group AG2,941,000$39.9M0.39%+90,990+3.2%Added
Rock Springs Capital Management LP2,845,618$38.6M0.77%+70,491+2.5%Added
OrbiMed Advisors LLC2,800,247$38.0M0.39%+907,747+48.0%Added
Price T Rowe Associates Inc2,317,747$31.5M0.00%−656,340−22.1%Reduced
Westfield Capital Management Co LP2,108,810$28.6M0.17%+110,172+5.5%Added
Candriam Luxembourg S.C.A.1,972,895$26.8M0.18%+850,722+75.8%Added
Alkeon Capital Management LLC1,806,267$24.5M0.09%−4,238−0.2%Reduced
Pictet Asset Management Ltd1,712,147$23.3M0.03%+8,248+0.5%Added
Artal Group S.A.1,200,000$16.3M0.37%00.0%Unchanged
CIBC Asset Management Inc1,058,506$14.4M0.06%+730,887+223.1%Added
Geode Capital Management, LLC1,051,919$14.3M0.00%+93,868+9.8%Added
Assenagon Asset Management S.A.1,040,942$14.1M0.06%+1,040,942New
Rho Capital Partners Inc796,458$10.8M0.99%00.0%Unchanged
Northern Trust Corp682,687$9.27M0.00%+89,467+15.1%Added
Citadel Advisors LLC589,123$8.00M0.01%+50,716+9.4%Added
Goldman Sachs Group Inc576,955$7.83M0.00%−580,435−50.2%Reduced
Two Sigma Advisers, LP567,600$7.71M0.02%−19,100−3.3%Reduced
Two Sigma Investments, LP564,030$7.66M0.02%+178,460+46.3%Added
Ghost Tree Capital, LLC450,000$6.11M1.91%00.0%Unchanged
Commodore Capital LP429,228$5.83M2.03%00.0%Unchanged
Charles Schwab Investment Management Inc412,473$5.60M0.00%+42,290+11.4%Added
FMR LLC380,029$5.16M0.00%−348,900−47.9%Reduced
Millennium Management LLC326,143$4.43M0.01%+38,472+13.4%Added
Allianz Asset Management GmbH283,450$3.85M0.00%+1,467+0.5%Added
Nuveen Asset Management, LLC259,948$3.53M0.00%+17,519+7.2%Added
Bank of New York Mellon Corp249,001$3.38M0.00%−12,510−4.8%Reduced
Deutsche Bank AG196,326$2.67M0.00%−23,072−10.5%Reduced
Citigroup Inc185,464$2.52M0.00%−44,637−19.4%Reduced
Dimensional Fund Advisors LP176,004$2.39M0.00%−2,839−1.6%Reduced
Sio Capital Management, LLC157,259$2.14M0.58%00.0%Unchanged
STRS Ohio153,742$2.09M0.01%00.0%Unchanged
Macquarie Group Ltd151,498$2.06M0.00%00.0%Unchanged
DAFNA Capital Management LLC128,263$1.74M0.36%+4,000+3.2%Added
Morgan Stanley126,177$1.71M0.00%+112,940+853.2%Added
Silverarc Capital Management, LLC125,123$1.70M0.89%+100,123+400.5%Added
Swiss National Bank120,796$1.64M0.00%−4,500−3.6%Reduced
Comerica Bank147,312$1.61M0.01%+54,066+58.0%Added
Rafferty Asset Management, LLC117,478$1.59M0.01%−67,630−36.5%Reduced
Bailard, Inc.111,000$1.51M0.05%−20,000−15.3%Reduced
Platinum Investment Management Ltd110,906$1.51M0.03%00.0%Unchanged
Susquehanna International Group, LLP110,602$1.50M0.00%−20,777−15.8%Reduced
California State Teachers Retirement System94,917$1.29M0.00%+14,647+18.2%Added
Maven Securities LTD84,469$1.17M0.12%+84,469New
Affinity Asset Advisors, LLC85,000$1.15M0.55%00.0%Unchanged
Rhumbline Advisers80,334$1.09M0.00%+12,462+18.4%Added
State of Wisconsin Investment Board79,700$1.08M0.00%−11,300−12.4%Reduced
Alliancebernstein L.P.72,000$978.0K0.00%00.0%Unchanged
Hudson Bay Capital Management LP70,000$951.0K0.01%+70,000New
QVT Financial LP62,657$851.0K0.06%00.0%Unchanged
Qube Research & Technologies Ltd62,685$851.0K0.01%+62,685New
HighVista Strategies LLC59,906$814.0K0.58%+59,906New
TD Asset Management Inc73,954$813.0K0.00%−13,403−15.3%Reduced
New York State Common Retirement Fund59,445$807.0K0.00%+11,145+23.1%Added
Barclays PLC57,365$778.0K0.00%−68,063−54.3%Reduced
Bank of America Corp55,232$750.0K0.00%+21,841+65.4%Added
Caption Management, LLC54,700$742.0K0.07%−191,447−77.8%Reduced
Credit Suisse AG54,157$736.0K0.00%+715+1.3%Added
Jane Street Group, LLC52,372$712.0K0.00%−10,963−17.3%Reduced
FIL Ltd52,415$712.0K0.00%00.0%Unchanged
AlphaCentric Advisors LLC45,500$618.0K0.17%+15,000+49.2%Added
Engineers Gate Manager LP43,592$592.0K0.04%+31,732+267.6%Added
UBS Asset Management Americas Inc43,419$589.6K0.00%+3,852+9.7%Added
Squarepoint Ops LLC42,507$577.0K0.00%−12,908−23.3%Reduced
D. E. Shaw & Co., Inc.40,085$544.0K0.00%−113,986−74.0%Reduced
Manufacturers Life Insurance Company, The39,806$541.0K0.00%+9,265+30.3%Added
Walleye Capital LLC38,815$527.0K0.02%+38,815New
American International Group, Inc.38,588$524.0K0.00%+7,563+24.4%Added
Teachers Retirement System of the State of Kentucky36,839$500.0K0.00%00.0%Unchanged
Parametric Portfolio Associates LLC35,986$489.0K0.00%−3,815−9.6%Reduced
ProShare Advisors LLC30,366$412.0K0.00%+6,587+27.7%Added
Skandinaviska Enskilda Banken AB (publ)30,304$412.0K0.00%+30,304New
JPMorgan Chase & Co29,860$405.0K0.00%−112,314−79.0%Reduced
Cowen and Company, LLC29,397$399.0K0.02%+8,297+39.3%Added
Invesco Ltd.27,045$368.0K0.00%−385,125−93.4%Reduced
State Board of Administration of Florida Retirement System27,117$368.0K0.00%+4,757+21.3%Added
Point72 Asset Management, L.P.26,900$365.0K0.00%−1,016,200−97.4%Reduced
Voya Investment Management LLC26,438$359.0K0.00%+3,488+15.2%Added
Principal Financial Group Inc26,040$353.0K0.00%−55,116−67.9%Reduced
MetLife Investment Management25,825$350.7K0.00%+4,676+22.1%Added
Prio Wealth Limited Partnership23,529$320.0K0.01%00.0%Unchanged
UBS Group AG23,436$318.0K0.00%−63,645−73.1%Reduced
Jasper Ridge Partners, L.P.23,100$314.0K0.02%00.0%Unchanged
Schonfeld Strategic Advisors LLC22,500$306.0K0.00%−23,402−51.0%Reduced
Twinbeech Capital LP21,570$293.0K0.04%+21,570New
ExodusPoint Capital Management, LP21,147$287.0K0.00%+21,147New
Cubist Systematic Strategies, LLC20,228$275.0K0.00%+14,350+244.1%Added
DekaBank Deutsche Girozentrale21,000$274.0K0.00%00.0%Unchanged
Marshall Wace, LLP19,845$269.0K0.00%−132,265−87.0%Reduced
Dynamic Technology Lab Private Ltd19,821$269.0K0.03%+19,821New
Metropolitan Life Insurance Co19,772$268.5K0.00%+5,167+35.4%Added
Truist Financial Corp16,700$227.0K0.00%+5,000+42.7%Added
Quantbot Technologies LP16,200$219.0K0.02%+16,200New
Boothbay Fund Management, LLC16,071$218.0K0.01%+16,071New