Citadel Advisors’s Biogen BIIB Stock Holding History
Bought
Maintained
Sold
| Quarter | Market Value | Status | Shares |
Change in Stake | Trade Value | Portfolio Weight | Portfolio Position | |
|---|---|---|---|---|---|---|---|---|
|
2026
Q1 | $55M | Sell |
299,900
-107,100
| -26% | -$19.7M | 0.01% | 1275 |
|
|
2025
Q4 | $71.6M | Buy |
407,000
+165,800
| +69% | +$27.1M | 0.01% | 1107 |
|
|
2025
Q3 | $33.8M | Sell |
241,200
-231,900
| -49% | -$31.3M | 0.01% | 1752 |
|
|
2025
Q2 | $59.4M | Buy |
473,100
+267,000
| +130% | +$33.3M | 0.01% | 1107 |
|
|
2025
Q1 | $28.2M | Buy |
206,100
+33,700
| +20% | +$4.82M | 0.01% | 1663 |
|
|
2024
Q4 | $26.4M | Buy |
172,400
+64,600
| +60% | +$10.9M | ﹤0.01% | 1875 |
|
|
2024
Q3 | $20.9M | Sell |
107,800
-8,600
| -7% | -$1.8M | ﹤0.01% | 2008 |
|
|
2024
Q2 | $27M | Sell |
116,400
-15,100
| -11% | -$3.28M | 0.01% | 1700 |
|
|
2024
Q1 | $28.4M | Sell |
131,500
-111,100
| -46% | -$26M | 0.01% | 1719 |
|
|
2023
Q4 | $62.8M | Sell |
242,600
-4,600
| -2% | -$1.13M | 0.01% | 1007 |
|
|
2023
Q3 | $63.5M | Sell |
247,200
-124,600
| -34% | -$33.3M | 0.01% | 902 |
|
|
2023
Q2 | $106M | Sell |
371,800
-152,700
| -29% | -$45.5M | 0.02% | 582 |
|
|
2023
Q1 | $146M | Sell |
524,500
-351,100
| -40% | -$97.1M | 0.03% | 440 |
|
|
2022
Q4 | $242M | Sell |
875,600
-522,700
| -37% | -$148M | 0.06% | 272 |
|
|
2022
Q3 | $373M | Buy |
1,398,300
+843,600
| +152% | +$179M | 0.09% | 142 |
|
|
2022
Q2 | $113M | Sell |
554,700
-72,400
| -12% | -$14.8M | 0.03% | 514 |
|
|
2022
Q1 | $132M | Buy |
627,100
+22,000
| +4% | +$4.78M | 0.03% | 525 |
|
|
2021
Q4 | $145M | Sell |
605,100
-29,000
| -5% | -$7.46M | 0.03% | 472 |
|
|
2021
Q3 | $179M | Sell |
634,100
-255,400
| -29% | -$83.7M | 0.04% | 389 |
|
|
2021
Q2 | $308M | Buy |
889,500
+315,700
| +55% | +$95.6M | 0.07% | 187 |
|
|
2021
Q1 | $161M | Sell |
573,800
-351,500
| -38% | -$94.8M | 0.04% | 378 |
|
|
2020
Q4 | $227M | Buy |
925,300
+304,400
| +49% | +$78.5M | 0.06% | 223 |
|
|
2020
Q3 | $176M | Buy |
620,900
+70,500
| +13% | +$19.7M | 0.05% | 236 |
|
|
2020
Q2 | $147M | Sell |
550,400
-7,900
| -1% | -$2.37M | 0.05% | 265 |
|
|
2020
Q1 | $177M | Sell |
558,300
-308,200
| -36% | -$93.5M | 0.08% | 164 |
|
|
2019
Q4 | $257M | Buy |
866,500
+228,900
| +36% | +$63.5M | 0.11% | 126 |
|
|
2019
Q3 | $148M | Buy |
637,600
+93,500
| +17% | +$21.8M | 0.07% | 239 |
|
|
2019
Q2 | $127M | Buy |
544,100
+5,800
| +1% | +$1.34M | 0.06% | 296 |
|
|
2019
Q1 | $127M | Buy |
538,300
+286,200
| +114% | +$90.1M | 0.06% | 269 |
|
|
2018
Q4 | $75.9M | Sell |
252,100
-62,800
| -20% | -$20M | 0.04% | 432 |
|
|
2018
Q3 | $111M | Buy |
314,900
+102,300
| +48% | +$35.2M | 0.05% | 376 |
|
|
2018
Q2 | $61.7M | Buy |
212,600
+38,800
| +22% | +$10.9M | 0.03% | 591 |
|
|
2018
Q1 | $47.6M | Buy |
173,800
+10,900
| +7% | +$3.38M | 0.03% | 627 |
|
|
2017
Q4 | $51.9M | Sell |
162,900
-95,900
| -37% | -$30.8M | 0.03% | 593 |
|
|
2017
Q3 | $81M | Buy |
258,800
+21,800
| +9% | +$6.46M | 0.06% | 328 |
|
|
2017
Q2 | $64.3M | Buy |
237,000
+123,900
| +110% | +$32.8M | 0.05% | 387 |
|
|
2017
Q1 | $30.9M | Sell |
113,100
-148,000
| -57% | -$41.8M | 0.03% | 691 |
|
|
2016
Q4 | $74M | Buy |
261,100
+32,200
| +14% | +$9.54M | 0.07% | 245 |
|
|
2016
Q3 | $71.7M | Sell |
228,900
-30,700
| -12% | -$9.09M | 0.07% | 249 |
|
|
2016
Q2 | $62.8M | Buy |
259,600
+21,900
| +9% | +$5.77M | 0.07% | 256 |
|
|
2016
Q1 | $61.9M | Sell |
237,700
-114,300
| -32% | -$30.2M | 0.08% | 234 |
|
|
2015
Q4 | $108M | Sell |
352,000
-26,200
| -7% | -$7.53M | 0.12% | 177 |
|
|
2015
Q3 | $110M | Buy |
378,200
+33,800
| +10% | +$11.2M | 0.1% | 183 |
|
|
2015
Q2 | $139M | Buy |
344,400
+29,000
| +9% | +$11.6M | 0.12% | 163 |
|
|
2015
Q1 | $133M | Buy |
315,400
+53,100
| +20% | +$20.9M | 0.13% | 153 |
|
|
2014
Q4 | $89M | Buy |
262,300
+44,200
| +20% | +$14.3M | 0.09% | 233 |
|
|
2014
Q3 | $72.2M | Buy |
218,100
+34,200
| +19% | +$11.3M | 0.08% | 273 |
|
|
2014
Q2 | $58M | Sell |
183,900
-73,500
| -29% | -$22.1M | 0.07% | 318 |
|
|
2014
Q1 | $78.7M | Sell |
257,400
-94,300
| -27% | -$29.9M | 0.09% | 224 |
|
|
2013
Q4 | $98.4M | Buy |
351,700
+190,400
| +118% | +$49.2M | 0.13% | 155 |
|
|
2013
Q3 | $38.8M | Buy |
161,300
+1,100
| +0.7% | +$246K | 0.06% | 399 |
|
|
2013
Q2 | $34.5M | Buy |
+160,200
| New | +$34.2M | 0.06% | 380 |
|
Other funds holding BIIB
VCM
VPM
Citadel Advisors's BIIB Position: Q1 2026 in Review
Citadel Advisors increased its Biogen (BIIB) stake by 242% in Q1 2026, buying an estimated $18M and bringing the position to 138,093 shares worth $25.3M. The position accounts for ﹤0.01% of the portfolio, ranked #2046.
Citadel Advisors first reported a position in BIIB in Q2 2013 and has held it in 50 quarters since. The position peaked at $328M in Q2 2016. 1,004 funds tracked by Wall St. Rank hold BIIB as of Q1 2026.
- Citadel Advisors held 138,093 shares of Biogen worth $25.3M as of Q1 2026.
- Citadel Advisors bought 97,669 Biogen shares in Q1 2026, an estimated $18M.
- Biogen made up ﹤0.01% of Citadel Advisors's portfolio in Q1 2026, its #2046 holding.
- Citadel Advisors first reported a position in Biogen in Q2 2013 and has held it in 50 quarters since.
- Citadel Advisors's Biogen position peaked at $328M in Q2 2016.
- 1,004 funds tracked by Wall St. Rank held Biogen as of Q1 2026.
Based on Citadel Advisors's 13F filing for Q1 2026, filed 15 May 2026.