Mersana Therapeutics
MRSN
MRSN was delisted on the 5th of January, 2026.
46 hedge funds and large institutions have $198M invested in Mersana Therapeutics in 2018 Q3 according to their latest regulatory filings, with 3 funds opening new positions, 21 increasing their positions, 8 reducing their positions, and 10 closing their positions.
163% more repeat investments, than reductions
Existing positions increased: 21 | Existing positions reduced: 8
0.08% more ownership
Funds ownership: 3.34% → 3.42% (+0.08%)
13% less funds holding
Funds holding: 53 → 46 (-7)
25% less funds holding in top 10
Funds holding in top 10: 4 → 3 (-1)
42% less capital invested
Capital invested by funds: $342M → $198M (-$144M)
70% less first-time investments, than exits
New positions opened: 3 | Existing positions closed: 10
Top Buyers
| Rank | Fund | Capital Flow |
|---|---|---|
| 1 |
ACH
ArrowMark Colorado Holdings
Denver,
Colorado
|
+$7.9M |
| 2 |
EC
EcoR1 Capital
San Francisco,
California
|
+$6.64M |
| 3 |
Millennium Management
New York
|
+$3.31M |
| 4 |
Vanguard Group
Malvern,
Pennsylvania
|
+$2.06M |
| 5 |
Geode Capital Management
Boston,
Massachusetts
|
+$423K |
Top Sellers
| Rank | Fund | Capital Flow |
|---|---|---|
| 1 |
GTC
Ghost Tree Capital
New York
|
-$10.7M |
| 2 |
Point72 Asset Management
Stamford,
Connecticut
|
-$2.53M |
| 3 |
AllianceBernstein
Nashville,
Tennessee
|
-$1.03M |
| 4 |
Russell Investments Group
London,
United Kingdom
|
-$766K |
| 5 |
Balyasny Asset Management
Chicago,
Illinois
|
-$623K |
MRSN Hedge Fund Activity: Q3 2018 in Review
46 of the 4,391 institutional investors tracked by Wall St. Rank reported a position in Mersana Therapeutics (MRSN) for Q3 2018, worth a combined $198M — down 42% from $342M a quarter earlier.
Sellers outnumbered buyers: 10 funds closed out of MRSN and 3 opened new positions — a net loss of 7 holders — while 8 trimmed existing stakes and 21 added.
The largest buyer was ArrowMark Colorado Holdings, adding an estimated $7.9M. The largest seller was Ghost Tree Capital, exiting entirely with an estimated $10.7M sold.
- 46 institutional investors held Mersana Therapeutics (MRSN) as of Q3 2018, down from 53 in Q2 2018.
- Funds reported $198M of Mersana Therapeutics stock for Q3 2018, down 42% quarter-over-quarter.
- 3 funds opened new Mersana Therapeutics positions in Q3 2018 and 10 closed out, a net change of -7 holders.
- The largest Mersana Therapeutics buyer in Q3 2018 was ArrowMark Colorado Holdings, an estimated $7.9M added.
- The largest Mersana Therapeutics seller in Q3 2018 was Ghost Tree Capital, an estimated $10.7M sold.
Based on aggregated 13F filings for Q3 2018.