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 | $17M | Sell |
92,700
-69,300
| -43% | -$12.8M | ﹤0.01% | 2527 |
|
|
2025
Q4 | $28.5M | Buy |
162,000
+4,000
| +3% | +$653K | ﹤0.01% | 1957 |
|
|
2025
Q3 | $22.1M | Sell |
158,000
-105,800
| -40% | -$14.3M | ﹤0.01% | 2207 |
|
|
2025
Q2 | $33.1M | Sell |
263,800
-734,600
| -74% | -$91.5M | 0.01% | 1579 |
|
|
2025
Q1 | $137M | Buy |
998,400
+759,700
| +318% | +$109M | 0.03% | 524 |
|
|
2024
Q4 | $36.5M | Buy |
238,700
+87,600
| +58% | +$14.8M | 0.01% | 1554 |
|
|
2024
Q3 | $29.3M | Sell |
151,100
-7,300
| -5% | -$1.53M | 0.01% | 1703 |
|
|
2024
Q2 | $36.7M | Buy |
158,400
+34,400
| +28% | +$7.48M | 0.01% | 1411 |
|
|
2024
Q1 | $26.7M | Sell |
124,000
-59,500
| -32% | -$13.9M | 0.01% | 1781 |
|
|
2023
Q4 | $47.5M | Sell |
183,500
-112,800
| -38% | -$27.7M | 0.01% | 1235 |
|
|
2023
Q3 | $76.2M | Sell |
296,300
-79,300
| -21% | -$21.2M | 0.02% | 781 |
|
|
2023
Q2 | $107M | Sell |
375,600
-159,300
| -30% | -$47.4M | 0.02% | 574 |
|
|
2023
Q1 | $149M | Sell |
534,900
-456,400
| -46% | -$126M | 0.03% | 433 |
|
|
2022
Q4 | $275M | Sell |
991,300
-333,400
| -25% | -$94.2M | 0.06% | 229 |
|
|
2022
Q3 | $354M | Buy |
1,324,700
+740,400
| +127% | +$157M | 0.08% | 151 |
|
|
2022
Q2 | $119M | Buy |
584,300
+109,200
| +23% | +$22.3M | 0.03% | 484 |
|
|
2022
Q1 | $100M | Sell |
475,100
-104,700
| -18% | -$22.8M | 0.02% | 654 |
|
|
2021
Q4 | $139M | Sell |
579,800
-124,700
| -18% | -$32.1M | 0.03% | 498 |
|
|
2021
Q3 | $199M | Sell |
704,500
-172,000
| -20% | -$56.4M | 0.04% | 338 |
|
|
2021
Q2 | $304M | Sell |
876,500
-19,800
| -2% | -$6M | 0.07% | 193 |
|
|
2021
Q1 | $251M | Sell |
896,300
-92,500
| -9% | -$24.9M | 0.06% | 221 |
|
|
2020
Q4 | $242M | Buy |
988,800
+316,200
| +47% | +$81.6M | 0.06% | 197 |
|
|
2020
Q3 | $191M | Buy |
672,600
+66,800
| +11% | +$18.6M | 0.05% | 205 |
|
|
2020
Q2 | $162M | Sell |
605,800
-45,200
| -7% | -$13.6M | 0.06% | 231 |
|
|
2020
Q1 | $206M | Sell |
651,000
-209,600
| -24% | -$63.6M | 0.09% | 132 |
|
|
2019
Q4 | $255M | Buy |
860,600
+168,200
| +24% | +$46.7M | 0.11% | 127 |
|
|
2019
Q3 | $161M | Buy |
692,400
+228,500
| +49% | +$53.2M | 0.08% | 214 |
|
|
2019
Q2 | $108M | Sell |
463,900
-88,700
| -16% | -$20.5M | 0.05% | 368 |
|
|
2019
Q1 | $131M | Buy |
552,600
+203,600
| +58% | +$64.1M | 0.07% | 262 |
|
|
2018
Q4 | $105M | Sell |
349,000
-198,000
| -36% | -$63.2M | 0.06% | 306 |
|
|
2018
Q3 | $193M | Buy |
547,000
+245,500
| +81% | +$84.5M | 0.09% | 181 |
|
|
2018
Q2 | $87.5M | Buy |
301,500
+26,400
| +10% | +$7.42M | 0.04% | 420 |
|
|
2018
Q1 | $75.3M | Sell |
275,100
-102,100
| -27% | -$31.7M | 0.04% | 417 |
|
|
2017
Q4 | $120M | Buy |
377,200
+88,200
| +31% | +$28.3M | 0.07% | 271 |
|
|
2017
Q3 | $90.5M | Buy |
289,000
+3,200
| +1% | +$948K | 0.07% | 294 |
|
|
2017
Q2 | $77.6M | Buy |
285,800
+87,000
| +44% | +$23M | 0.07% | 308 |
|
|
2017
Q1 | $54.4M | Sell |
198,800
-108,900
| -35% | -$30.8M | 0.05% | 416 |
|
|
2016
Q4 | $87.3M | Buy |
307,700
+15,700
| +5% | +$4.65M | 0.09% | 202 |
|
|
2016
Q3 | $91.4M | Sell |
292,000
-3,600
| -1% | -$1.07M | 0.09% | 183 |
|
|
2016
Q2 | $71.5M | Buy |
295,600
+57,400
| +24% | +$15.1M | 0.08% | 221 |
|
|
2016
Q1 | $62M | Sell |
238,200
-163,500
| -41% | -$43.2M | 0.08% | 232 |
|
|
2015
Q4 | $123M | Sell |
401,700
-51,200
| -11% | -$14.7M | 0.13% | 149 |
|
|
2015
Q3 | $132M | Buy |
452,900
+126,000
| +39% | +$41.6M | 0.13% | 146 |
|
|
2015
Q2 | $132M | Buy |
326,900
+11,600
| +4% | +$4.66M | 0.11% | 173 |
|
|
2015
Q1 | $133M | Sell |
315,300
-13,400
| -4% | -$5.28M | 0.13% | 154 |
|
|
2014
Q4 | $112M | Sell |
328,700
-5,900
| -2% | -$1.91M | 0.11% | 170 |
|
|
2014
Q3 | $111M | Buy |
334,600
+50,500
| +18% | +$16.7M | 0.12% | 163 |
|
|
2014
Q2 | $89.6M | Sell |
284,100
-33,200
| -10% | -$9.99M | 0.1% | 190 |
|
|
2014
Q1 | $97.1M | Buy |
317,300
+84,800
| +36% | +$26.9M | 0.11% | 177 |
|
|
2013
Q4 | $65M | Sell |
232,500
-12,000
| -5% | -$3.1M | 0.08% | 262 |
|
|
2013
Q3 | $58.9M | Buy |
244,500
+97,800
| +67% | +$21.9M | 0.09% | 250 |
|
|
2013
Q2 | $31.6M | Buy |
+146,700
| New | +$31.3M | 0.05% | 426 |
|
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.