Bought
Maintained
Sold
Quarter Market Value Status Shares Change in
Stake
Trade Value Portfolio Weight Portfolio Position
2026
Q1
$3.89M Sell
21,200
-57,900
-73% -$10.7M ﹤0.01% 2156
2025
Q4
$13.9M Hold
79,100
0.01% 1318
2025
Q3
$11.1M Hold
79,100
﹤0.01% 1408
2025
Q2
$9.93M Sell
79,100
-14,900
-16% -$1.86M ﹤0.01% 1372
2025
Q1
$12.9M Sell
94,000
-70,300
-43% -$10M 0.01% 1210
2024
Q4
$25.1M Buy
164,300
+161,100
+5,034% +$27.2M 0.01% 832
2024
Q3
$620K Sell
3,200
-15,000
-82% -$3.14M ﹤0.01% 3592
2024
Q2
$4.22M Buy
18,200
+15,000
+469% +$3.26M ﹤0.01% 1755
2024
Q1
$690K Sell
3,200
-44,900
-93% -$10.5M ﹤0.01% 3324
2023
Q4
$12.4M Sell
48,100
-32,100
-40% -$7.88M 0.01% 1105
2023
Q3
$20.6M Buy
80,200
+40,000
+100% +$10.7M 0.02% 771
2023
Q2
$11.5M Sell
40,200
-24,800
-38% -$7.38M 0.01% 1087
2023
Q1
$18.1M Buy
+65,000
New +$18M 0.01% 870
2022
Q4
Sell
-40,000
Closed -$10.7M 5780
2022
Q3
$10.7M Buy
40,000
+15,000
+60% +$3.19M 0.01% 1105
2022
Q2
$5.1M Buy
+25,000
New +$5.11M ﹤0.01% 1530
2022
Q1
Sell
-61,000
Closed -$14.6M 6306
2021
Q4
$14.6M Hold
61,000
0.01% 1184
2021
Q3
$17.3M Buy
61,000
+25,100
+70% +$8.23M 0.01% 1089
2021
Q2
$12.4M Buy
35,900
+18,400
+105% +$5.57M 0.01% 1279
2021
Q1
$4.9M Sell
17,500
-184,800
-91% -$49.8M ﹤0.01% 1802
2020
Q4
$49.5M Buy
202,300
+54,900
+37% +$14.2M 0.03% 546
2020
Q3
$41.8M Buy
147,400
+33,000
+29% +$9.2M 0.03% 525
2020
Q2
$30.6M Sell
114,400
-40,100
-26% -$12.1M 0.02% 594
2020
Q1
$48.9M Sell
154,500
-8,200
-5% -$2.49M 0.04% 367
2019
Q4
$48.3M Buy
162,700
+42,600
+35% +$11.8M 0.04% 525
2019
Q3
$28M Buy
120,100
+16,500
+16% +$3.84M 0.02% 740
2019
Q2
$24.2M Buy
103,600
+15,300
+17% +$3.53M 0.02% 826
2019
Q1
$20.9M Sell
88,300
-111,100
-56% -$35M 0.02% 806
2018
Q4
$60M Buy
199,400
+59,000
+42% +$18.8M 0.06% 333
2018
Q3
$49.6M Sell
140,400
-9,100
-6% -$3.13M 0.04% 395
2018
Q2
$43.4M Buy
149,500
+11,200
+8% +$3.15M 0.04% 414
2018
Q1
$37.9M Sell
138,300
-38,500
-22% -$12M 0.03% 491
2017
Q4
$56.3M Buy
176,800
+15,300
+9% +$4.91M 0.05% 391
2017
Q3
$50.6M Buy
161,500
+49,100
+44% +$14.5M 0.04% 396
2017
Q2
$30.5M Buy
112,400
+4,800
+4% +$1.27M 0.03% 562
2017
Q1
$29.4M Sell
107,600
-211,400
-66% -$59.8M 0.03% 578
2016
Q4
$90.5M Buy
319,000
+159,900
+101% +$47.4M 0.08% 231
2016
Q3
$49.8M Buy
159,100
+48,400
+44% +$14.3M 0.05% 341
2016
Q2
$26.8M Buy
110,700
+50,700
+85% +$13.4M 0.03% 528
2016
Q1
$15.6M Sell
60,000
-50,000
-45% -$13.2M 0.02% 739
2015
Q4
$33.7M Sell
110,000
-94,500
-46% -$27.2M 0.03% 499
2015
Q3
$59.7M Buy
204,500
+52,000
+34% +$17.2M 0.06% 295
2015
Q2
$61.6M Buy
152,500
+80,500
+112% +$32.3M 0.05% 326
2015
Q1
$30.4M Sell
72,000
-13,200
-15% -$5.2M 0.03% 569
2014
Q4
$28.9M Buy
85,200
+7,600
+10% +$2.46M 0.03% 622
2014
Q3
$25.7M Sell
77,600
-15,500
-17% -$5.11M 0.02% 670
2014
Q2
$29.4M Sell
93,100
-50,000
-35% -$15M 0.03% 570
2014
Q1
$43.8M Sell
143,100
-65,500
-31% -$20.8M 0.04% 376
2013
Q4
$58.4M Sell
208,600
-77,300
-27% -$20M 0.05% 325
2013
Q3
$68.8M Buy
285,900
+98,300
+52% +$22M 0.06% 268
2013
Q2
$40.4M Buy
+187,600
New +$40.1M 0.04% 395

Other funds holding BIIB

Citigroup's BIIB Position: Q1 2026 in Review

Citigroup reduced its Biogen (BIIB) stake by 13% in Q1 2026, selling an estimated $13.5M and leaving 500,507 shares worth $91.8M. The position accounts for 0.04% of the portfolio, ranked #433.

Citigroup first reported a position in BIIB in Q2 2013 and has held it in 52 quarters since. The position peaked at $101M in Q4 2025. 1,002 funds tracked by Wall St. Rank hold BIIB as of Q1 2026.

  • Citigroup held 500,507 shares of Biogen worth $91.8M as of Q1 2026.
  • Citigroup sold 73,337 Biogen shares in Q1 2026, an estimated $13.5M.
  • Biogen made up 0.04% of Citigroup's portfolio in Q1 2026, its #433 holding.
  • Citigroup first reported a position in Biogen in Q2 2013 and has held it in 52 quarters since.
  • Citigroup's Biogen position peaked at $101M in Q4 2025.
  • 1,002 funds tracked by Wall St. Rank held Biogen as of Q1 2026.

Based on Citigroup's 13F filing for Q1 2026, filed 11 May 2026.