JB
MRSN

Julian Baker’s Mersana Therapeutics MRSN Stock Holding History

Julian Baker’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
2025
Q1 		– Sell
-43,445
Closed -$1.55M – 95
2024
Q4 		$1.55M Hold
43,445
– – 0.02% 86
2024
Q3 		$2.05M Hold
43,445
– – 0.02% 80
2024
Q2 		$2.18M Hold
43,445
– – 0.03% 79
2024
Q1 		$4.87M Hold
43,445
– – 0.06% 62
2023
Q4 		$2.52M Hold
43,445
– – 0.03% 70
2023
Q3 		$1.38M Hold
43,445
– – 0.01% 93
2023
Q2 		$3.57M Sell
43,445
-32,000
-42% -$4.68M 0.02% 83
2023
Q1 		$7.75M Buy
+75,445
New +$10.6M 0.04% 59

Other funds holding MRSN

NI
Nextech Invest Zurich, Switzerland $2.11B AUM 413.84% 1-Year Est. Return
BCLSI
Bain Capital Life Sciences Investors Boston, Massachusetts $1.68B AUM 126.09% 1-Year Est. Return
Vanguard Group
Vanguard Group Malvern, Pennsylvania $6.9T AUM 27.45% 1-Year Est. Return
BlackRock
BlackRock New York $6.73T AUM 46.02% 1-Year Est. Return
SSA
Schonfeld Strategic Advisors New York $27.9B AUM 51.18% 1-Year Est. Return
AQR Capital Management
AQR Capital Management Greenwich, Connecticut $287B AUM 42.33% 1-Year Est. Return
RSCM
Rock Springs Capital Management Baltimore, Maryland $2.05B AUM 161.37% 1-Year Est. Return
VA
VR Adviser New York $3.3B AUM 525.74% 1-Year Est. Return
SCM
Silverarc Capital Management Boston, Massachusetts $962M AUM 524.64% 1-Year Est. Return
Acadian Asset Management
Acadian Asset Management Boston, Massachusetts $84.2B AUM 55.88% 1-Year Est. Return

Julian Baker's MRSN Position: Q1 2025 in Review

Julian Baker sold out of Mersana Therapeutics (MRSN) in Q1 2025, closing a stake of 43,445 shares — an estimated $1.55M sold.

Julian Baker first reported a position in MRSN in Q1 2023 and held it in 8 quarters. The position peaked at $7.75M in Q1 2023. 108 funds tracked by Wall St. Rank hold MRSN as of Q1 2025.

  • Julian Baker reported no remaining Mersana Therapeutics position as of Q1 2025 after selling out during the quarter.
  • Julian Baker sold 43,445 Mersana Therapeutics shares in Q1 2025, an estimated $1.55M.
  • Julian Baker first reported a position in Mersana Therapeutics in Q1 2023 and held it in 8 quarters.
  • Julian Baker's Mersana Therapeutics position peaked at $7.75M in Q1 2023.
  • 108 funds tracked by Wall St. Rank held Mersana Therapeutics as of Q1 2025.

Based on Baker Bros. Advisors's 13F filing for Q1 2025, filed 15 May 2025.