Citadel Advisors’s Mersana Therapeutics MRSN Stock Holding History

Bought
Maintained
Sold
Quarter Market Value Status Shares Change in
Stake
Trade Value Portfolio Weight Portfolio Position
2025
Q3
Sell
-1,372
Closed -$10.2K 13620
2025
Q2
$10.2K Buy
1,372
+720
+110% +$6.33K ﹤0.01% 12199
2025
Q1
$5.61K Sell
652
-1,184
-64% -$18.3K ﹤0.01% 13806
2024
Q4
$65.6K Buy
1,836
+748
+69% +$38.7K ﹤0.01% 12064
2024
Q3
$51.4K Buy
1,088
+80
+8% +$3.53K ﹤0.01% 11878
2024
Q2
$50.7K Buy
1,008
+180
+22% +$13K ﹤0.01% 11745
2024
Q1
$92.7K Sell
828
-868
-51% -$86.3K ﹤0.01% 11461
2023
Q4
$98.4K Sell
1,696
-2,544
-60% -$102K ﹤0.01% 10954
2023
Q3
$135K Sell
4,240
-2,200
-34% -$105K ﹤0.01% 10518
2023
Q2
$530K Buy
6,440
+6,008
+1,391% +$879K ﹤0.01% 7815
2023
Q1
$44.4K Buy
432
+272
+170% +$38.2K ﹤0.01% 12315
2022
Q4
$23.4K Buy
+160
New +$27K ﹤0.01% 13014
2022
Q2
Sell
-424
Closed -$42K 13655
2022
Q1
$42K Buy
+424
New +$49.5K ﹤0.01% 12907
2021
Q4
Sell
-568
Closed -$134K 14403
2021
Q3
$134K Buy
+568
New +$166K ﹤0.01% 12505
2021
Q2
Sell
-1,096
Closed -$443K 14119
2021
Q1
$443K Buy
+1,096
New +$532K ﹤0.01% 9950
2020
Q4
Sell
-1,140
Closed -$531K 11291
2020
Q3
$531K Buy
1,140
+556
+95% +$281K ﹤0.01% 7188
2020
Q2
$342K Buy
+584
New +$199K ﹤0.01% 7699

Other funds holding MRSN

Citadel Advisors's MRSN Position: Q1 2026 in Review

Citadel Advisors sold out of Mersana Therapeutics (MRSN) in Q1 2026, closing a stake of 22,493 shares — an estimated $651K sold.

Citadel Advisors first reported a position in MRSN in Q2 2017 and held it in 27 quarters. The position peaked at $52M in Q4 2020. 1 fund tracked by Wall St. Rank holds MRSN as of Q1 2026.

  • Citadel Advisors reported no remaining Mersana Therapeutics position as of Q1 2026 after selling out during the quarter.
  • Citadel Advisors sold 22,493 Mersana Therapeutics shares in Q1 2026, an estimated $651K.
  • Citadel Advisors first reported a position in Mersana Therapeutics in Q2 2017 and held it in 27 quarters.
  • Citadel Advisors's Mersana Therapeutics position peaked at $52M in Q4 2020.
  • 1 fund tracked by Wall St. Rank held Mersana Therapeutics as of Q1 2026.

Based on Citadel Advisors's 13F filing for Q1 2026, filed 15 May 2026.