Hudson Bay Capital Management
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Hudson Bay Capital Management’s Biogen BIIB Stock Holding History

Hudson Bay Capital Management’s Portfolio BIIB Stock Details BIIB Fund Activity
Bought
Maintained
Sold
Quarter Market Value Status Shares Change in
Stake 		Trade Value Portfolio Weight Portfolio Position
2026
Q1 		$36.9M Sell
201,367
-20,493
-9% -$3.78M 0.13% 137
2025
Q4 		$39M Sell
221,860
-31,291
-12% -$5.11M 0.13% 146
2025
Q3 		$35.5M Sell
253,151
-14,589
-5% -$1.97M 0.12% 146
2025
Q2 		$33.6M Buy
267,740
+67,220
+34% +$8.38M 0.11% 142
2025
Q1 		$27.4M Sell
200,520
-40,488
-17% -$5.79M 0.08% 213
2024
Q4 		$36.9M Sell
241,008
-58,992
-20% -$9.95M 0.13% 165
2024
Q3 		$58.2M Buy
300,000
+105,000
+54% +$22M 0.24% 73
2024
Q2 		$45.2M Sell
195,000
-30,000
-13% -$6.52M 0.21% 75
2024
Q1 		$48.5M Buy
225,000
+90,000
+67% +$21.1M 0.27% 56
2023
Q4 		$34.9M Buy
135,000
+52,500
+64% +$12.9M 0.22% 73
2023
Q3 		$21.2M Buy
82,500
+25,000
+43% +$6.69M 0.17% 92
2023
Q2 		$16.4M Sell
57,500
-51,806
-47% -$15.4M 0.12% 120
2023
Q1 		$30.4M Buy
109,306
+56,806
+108% +$15.7M 0.25% 81
2022
Q4 		$14.5M Buy
52,500
+5,000
+11% +$1.41M 0.15% 120
2022
Q3 		$12.7M Buy
47,500
+22,500
+90% +$4.78M 0.11% 125
2022
Q2 		$5.1M Buy
25,000
+10,000
+67% +$2.04M 0.04% 416
2022
Q1 		$3.16M Sell
15,000
-29,000
-66% -$6.31M 0.04% 554
2021
Q4 		$10.6M Buy
44,000
+24,000
+120% +$6.17M 0.11% 124
2021
Q3 		$5.66M Buy
20,000
+5,000
+33% +$1.64M 0.08% 292
2021
Q2 		$5.19M Buy
+15,000
New +$4.54M 0.06% 324
2021
Q1 		– Sell
-20,000
Closed -$4.9M – 859
2020
Q4 		$4.9M Sell
20,000
-30,000
-60% -$7.74M 0.05% 242
2020
Q3 		$14.2M Buy
50,000
+2,500
+5% +$697K 0.21% 82
2020
Q2 		$12.7M Buy
47,500
+37,500
+375% +$11.3M 0.22% 72
2020
Q1 		$3.16M Buy
+10,000
New +$3.03M 0.08% 207
2019
Q3 		– Sell
-7,500
Closed -$1.75M – 412
2019
Q2 		$1.75M Sell
7,500
-26,300
-78% -$6.07M 0.04% 290
2019
Q1 		$7.99M Buy
33,800
+19,100
+130% +$6.01M 0.1% 190
2018
Q4 		$4.42M Sell
14,700
-15,300
-51% -$4.88M 0.06% 332
2018
Q3 		$10.6M Hold
30,000
– – 0.13% 138
2018
Q2 		$8.71M Sell
30,000
-10,000
-25% -$2.81M 0.12% 162
2018
Q1 		$11M Buy
40,000
+25,000
+167% +$7.76M 0.23% 94
2017
Q4 		$4.78M Hold
15,000
– – 0.1% 172
2017
Q3 		$4.7M Sell
15,000
-20,000
-57% -$5.92M 0.12% 151
2017
Q2 		$9.5M Buy
+35,000
New +$9.25M 0.19% 111
2017
Q1 		– Sell
-71,402
Closed -$20.2M – 792
2016
Q4 		$20.2M Sell
71,402
-36,907
-34% -$10.9M 0.42% 46
2016
Q3 		$33.9M Buy
+108,309
New +$32.1M 0.82% 24

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Geode Capital Management
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Wellington Management Group
Wellington Management Group Boston, Massachusetts $535B AUM 26.23% 1-Year Est. Return
Morgan Stanley
Morgan Stanley New York $1.66T AUM 25.57% 1-Year Est. Return
JP Morgan Chase
JP Morgan Chase New York $1.56T AUM 27.86% 1-Year Est. Return

Hudson Bay Capital Management's BIIB Position: Q1 2026 in Review

Hudson Bay Capital Management reduced its Biogen (BIIB) stake by 9.2% in Q1 2026, selling an estimated $3.78M and leaving 201,367 shares worth $36.9M. The position accounts for 0.13% of the portfolio, ranked #137.

Hudson Bay Capital Management first reported a position in BIIB in Q3 2016 and has held it in 35 quarters since. The position peaked at $58.2M in Q3 2024. 1,003 funds tracked by Wall St. Rank hold BIIB as of Q1 2026.

  • Hudson Bay Capital Management held 201,367 shares of Biogen worth $36.9M as of Q1 2026.
  • Hudson Bay Capital Management sold 20,493 Biogen shares in Q1 2026, an estimated $3.78M.
  • Biogen made up 0.13% of Hudson Bay Capital Management's portfolio in Q1 2026, its #137 holding.
  • Hudson Bay Capital Management first reported a position in Biogen in Q3 2016 and has held it in 35 quarters since.
  • Hudson Bay Capital Management's Biogen position peaked at $58.2M in Q3 2024.
  • 1,003 funds tracked by Wall St. Rank held Biogen as of Q1 2026.

Based on Hudson Bay Capital Management's 13F filing for Q1 2026, filed 13 May 2026.