UOC
MRSN

UBS O'Connor’s Mersana Therapeutics MRSN Stock Holding History

UBS O'Connor’s Portfolio MRSN Stock Details MRSN Fund Activity
Bought
Maintained
Sold
Quarter Market Value Status Shares Change in
Stake 		Trade Value Portfolio Weight Portfolio Position
2023
Q3 		– Sell
-16,600
Closed -$115K – 601
2023
Q2 		$115K Buy
+16,600
New +$2.43M ﹤0.01% 489

Other funds holding MRSN

NI
Nextech Invest Zurich, Switzerland $1.42B AUM 304.47% 1-Year Est. Return
BCLSI
Bain Capital Life Sciences Investors Boston, Massachusetts $1.11B AUM 171.34% 1-Year Est. Return
Vanguard Group
Vanguard Group Malvern, Pennsylvania $6.9T AUM 27.45% 1-Year Est. Return
SSA
Schonfeld Strategic Advisors New York $14.2B AUM 37.17% 1-Year Est. Return
AQR Capital Management
AQR Capital Management Greenwich, Connecticut $218B AUM 29.41% 1-Year Est. Return
RSCM
Rock Springs Capital Management Baltimore, Maryland $1.7B AUM 93.03% 1-Year Est. Return
BlackRock
BlackRock New York $6.73T AUM 46.02% 1-Year Est. Return
SCM
Silverarc Capital Management Boston, Massachusetts $980M AUM 470.8% 1-Year Est. Return
Acadian Asset Management
Acadian Asset Management Boston, Massachusetts $70.5B AUM 36% 1-Year Est. Return
Renaissance Technologies
Renaissance Technologies New York $63.9B AUM 45.56% 1-Year Est. Return

UBS O'Connor's MRSN Position: Q2 2025 in Review

UBS O'Connor sold out of Mersana Therapeutics (MRSN) in Q2 2025, closing a stake of 3,909 shares — an estimated $33.6K sold.

UBS O'Connor first reported a position in MRSN in Q2 2022 and held it in 10 quarters. The position peaked at $2.54M in Q3 2022. 83 funds tracked by Wall St. Rank hold MRSN as of Q2 2025.

  • UBS O'Connor reported no remaining Mersana Therapeutics position as of Q2 2025 after selling out during the quarter.
  • UBS O'Connor sold 3,909 Mersana Therapeutics shares in Q2 2025, an estimated $33.6K.
  • UBS O'Connor first reported a position in Mersana Therapeutics in Q2 2022 and held it in 10 quarters.
  • UBS O'Connor's Mersana Therapeutics position peaked at $2.54M in Q3 2022.
  • 83 funds tracked by Wall St. Rank held Mersana Therapeutics as of Q2 2025.

Based on UBS O'Connor's 13F filing for Q2 2025, filed 14 Aug 2025.