Vault-13

MERSANA THERAPEUTICS INC

COM · CUSIP 59045L106

0 institutional holders -3 vs Q4 2025
—reported value*
0 new 0 added 0 reduced 3 sold out net sold ≈ $2.9k (-99 shares)

* Summed across managers. Shares that two managers' reports both contain – a subsidiary's holdings that its parent's report includes too, or a sub-adviser's in its client's – are counted once. Holder counts are more reliable.

Trends to Q1 2026

Institutional holders

Managers reporting a position, each quarter

0100200Q3 22: 153Q4 22: 153Q1 23: 159Q2 23: 148Q3 23: 129Q4 23: 107Q1 24: 126Q2 24: 123Q3 24: 117Q4 24: 133Q1 25: 112Q2 25: 84Q3 25: 7Q4 25: 3Q1 26: 00Q3 22Q3 23Q3 24Q3 25Q1 26
Numbers
QuarterHolders
Q3 2022153
Q4 2022153
Q1 2023159
Q2 2023148
Q3 2023129
Q4 2023107
Q1 2024126
Q2 2024123
Q3 2024117
Q4 2024133
Q1 2025112
Q2 202584
Q3 20257
Q4 20253
Q1 20260

Buyers vs sellers

Managers adding to or starting a position, vs cutting or selling out

Bought or addedCut or sold out
1000100Q2 24: 62 bought or addedQ2 24: 57 cut or sold outQ3 24: 49 bought or addedQ3 24: 50 cut or sold outQ3 24Q4 24: 53 bought or addedQ4 24: 53 cut or sold outQ1 25: 50 bought or addedQ1 25: 79 cut or sold outQ1 25Q2 25: 34 bought or addedQ2 25: 70 cut or sold outQ3 25: 0 bought or addedQ3 25: 83 cut or sold outQ3 25Q4 25: 0 bought or addedQ4 25: 6 cut or sold outQ1 26: 0 bought or addedQ1 26: 3 cut or sold outQ1 26
Numbers
QuarterBought or addedCut or sold out
Q2 20246257
Q3 20244950
Q4 20245353
Q1 20255079
Q2 20253470
Q3 2025083
Q4 202506
Q1 202603

Calls vs puts

Options held, notional value, last 4 quarters. P/C = puts ÷ calls

CallsPuts
$0$5k$10k$15kQ2 25 calls: $14.1kQ2 25 puts: $4.3kQ2 25P/C 0.31Q3 25 calls: $0Q3 25 puts: $0Q3 25P/C —Q4 25 calls: $0Q4 25 puts: $0Q4 25P/C —Q1 26 calls: $0Q1 26 puts: $0Q1 26P/C —
Numbers
QuarterCallsPutsP/C
Q2 2025$14.1k$4.3k0.31
Q3 2025$0$0—
Q4 2025$0$0—
Q1 2026$0$0—

Biggest buyers

None

Biggest sellers

Essential Partners LLC Sold out -82-82
EverSource Wealth Advisors, LLC Sold out -11-11
North Star Investment Management Corp. Sold out -6-6

Major shareholders (over 5%)

Anyone who owns more than 5% of a class of the company's shares has to say so: on Schedule 13D if they may try to influence or control the company, on 13G if they're a passive investor, and update it as the stake changes. Each holder's latest filing, from 19 Dec 2024 on; percentages are of the share class, as the holder worked them out.

HolderStakeChangeShares Last filed
Nextech Crossover I GP S.a r.l. 13G · passive investor filed 2024-12-26 10.4% 12.1m 2024-12-26
VANGUARD GROUP INC 13G · institution filed 2025-04-30 6.7% 8.4m 2025-04-30

Fell to 5% or below in the last year: Schonfeld Strategic Advisors LLC (0.0%, 2026-02-17)

Holders, Q1 2026

#ManagerLocationShares Value% of their portfolioChangeShares change