BlackRock’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 | $2.93B | Buy |
15,974,601
+1,163,231
| +8% | +$214M | 0.05% | 310 |
|
|
2025
Q4 | $2.61B | Buy |
14,811,370
+47,418
| +0.3% | +$7.75M | 0.04% | 329 |
|
|
2025
Q3 | $2.07B | Buy |
14,763,952
+1,208,486
| +9% | +$163M | 0.04% | 397 |
|
|
2025
Q2 | $1.7B | Sell |
13,555,466
-1,655,570
| -11% | -$206M | 0.03% | 441 |
|
|
2025
Q1 | $2.08B | Sell |
15,211,036
-262,674
| -2% | -$37.6M | 0.04% | 360 |
|
|
2024
Q4 | $2.37B | Buy |
15,473,710
+126,669
| +0.8% | +$21.4M | 0.05% | 337 |
|
|
2024
Q3 | $2.97B | Buy |
15,347,041
+808,544
| +6% | +$169M | 0.06% | 274 |
|
|
2024
Q2 | $3.37B | Buy |
14,538,497
+393,509
| +3% | +$85.5M | 0.08% | 221 |
|
|
2024
Q1 | $3.05B | Sell |
14,144,988
-101,670
| -0.7% | -$23.8M | 0.07% | 254 |
|
|
2023
Q4 | $3.69B | Buy |
14,246,658
+272,071
| +2% | +$66.8M | 0.09% | 190 |
|
|
2023
Q3 | $3.59B | Sell |
13,974,587
-91,407
| -0.6% | -$24.4M | 0.1% | 170 |
|
|
2023
Q2 | $4.01B | Buy |
14,065,994
+79,773
| +0.6% | +$23.7M | 0.11% | 157 |
|
|
2023
Q1 | $3.89B | Sell |
13,986,221
-274,392
| -2% | -$75.9M | 0.11% | 149 |
|
|
2022
Q4 | $3.95B | Buy |
14,260,613
+413,887
| +3% | +$117M | 0.12% | 158 |
|
|
2022
Q3 | $3.7B | Sell |
13,846,726
-616,733
| -4% | -$131M | 0.13% | 146 |
|
|
2022
Q2 | $2.95B | Buy |
14,463,459
+342,362
| +2% | +$70M | 0.09% | 201 |
|
|
2022
Q1 | $2.97B | Buy |
14,121,097
+399,143
| +3% | +$86.8M | 0.08% | 236 |
|
|
2021
Q4 | $3.29B | Sell |
13,721,954
-174,299
| -1% | -$44.8M | 0.08% | 222 |
|
|
2021
Q3 | $3.93B | Buy |
13,896,253
+689,662
| +5% | +$226M | 0.11% | 152 |
|
|
2021
Q2 | $4.57B | Sell |
13,206,591
-296,037
| -2% | -$89.7M | 0.13% | 135 |
|
|
2021
Q1 | $3.78B | Buy |
13,502,628
+83,027
| +0.6% | +$22.4M | 0.11% | 163 |
|
|
2020
Q4 | $3.29B | Sell |
13,419,601
-1,043,678
| -7% | -$269M | 0.1% | 166 |
|
|
2020
Q3 | $4.1B | Sell |
14,463,279
-136,177
| -0.9% | -$38M | 0.15% | 122 |
|
|
2020
Q2 | $3.91B | Sell |
14,599,456
-1,443,581
| -9% | -$434M | 0.16% | 118 |
|
|
2020
Q1 | $5.08B | Buy |
16,043,037
+384,396
| +2% | +$117M | 0.25% | 74 |
|
|
2019
Q4 | $4.65B | Buy |
15,658,641
+219,594
| +1% | +$60.9M | 0.18% | 103 |
|
|
2019
Q3 | $3.59B | Sell |
15,439,047
-573,590
| -4% | -$134M | 0.15% | 124 |
|
|
2019
Q2 | $3.74B | Sell |
16,012,637
-280,115
| -2% | -$64.7M | 0.16% | 113 |
|
|
2019
Q1 | $3.85B | Sell |
16,292,752
-276,211
| -2% | -$87M | 0.17% | 103 |
|
|
2018
Q4 | $4.99B | Buy |
16,568,963
+70,603
| +0.4% | +$22.5M | 0.25% | 72 |
|
|
2018
Q3 | $5.83B | Sell |
16,498,360
-584,223
| -3% | -$201M | 0.25% | 72 |
|
|
2018
Q2 | $4.96B | Sell |
17,082,583
-185,756
| -1% | -$52.2M | 0.23% | 76 |
|
|
2018
Q1 | $4.73B | Buy |
17,268,339
+463,656
| +3% | +$144M | 0.23% | 79 |
|
|
2017
Q4 | $5.35B | Sell |
16,804,683
-139,606
| -0.8% | -$44.8M | 0.25% | 69 |
|
|
2017
Q3 | $5.31B | Sell |
16,944,289
-1,163,069
| -6% | -$344M | 0.27% | 66 |
|
|
2017
Q2 | $4.91B | Buy |
18,107,358
+415,099
| +2% | +$110M | 0.26% | 68 |
|
|
2017
Q1 | $4.84B | Buy |
17,692,259
+17,074,075
| +2,762% | +$4.83B | 0.27% | 68 |
|
|
2016
Q4 | $175M | Buy |
618,184
+32,119
| +5% | +$9.52M | 0.25% | 73 |
|
|
2016
Q3 | $183M | Sell |
586,065
-63,123
| -10% | -$18.7M | 0.26% | 74 |
|
|
2016
Q2 | $157M | Buy |
649,188
+86,484
| +15% | +$22.8M | 0.24% | 87 |
|
|
2016
Q1 | $146M | Sell |
562,704
-157,354
| -22% | -$41.6M | 0.24% | 85 |
|
|
2015
Q4 | $221M | Buy |
720,058
+2,480
| +0.3% | +$713K | 0.32% | 62 |
|
|
2015
Q3 | $209M | Buy |
717,578
+70,057
| +11% | +$23.1M | 0.33% | 63 |
|
|
2015
Q2 | $262M | Sell |
647,521
-65,817
| -9% | -$26.4M | 0.39% | 54 |
|
|
2015
Q1 | $301M | Sell |
713,338
-5,410
| -0.8% | -$2.13M | 0.42% | 56 |
|
|
2014
Q4 | $244M | Buy |
718,748
+14,708
| +2% | +$4.76M | 0.35% | 59 |
|
|
2014
Q3 | $233M | Sell |
704,040
-53,947
| -7% | -$17.8M | 0.34% | 65 |
|
|
2014
Q2 | $239M | Buy |
757,987
+49,426
| +7% | +$14.9M | 0.36% | 58 |
|
|
2014
Q1 | $217M | Buy |
708,561
+40,418
| +6% | +$12.8M | 0.35% | 60 |
|
|
2013
Q4 | $187M | Buy |
668,143
+118,058
| +21% | +$30.5M | 0.3% | 68 |
|
|
2013
Q3 | $132M | Sell |
550,085
-5,297
| -1% | -$1.19M | 0.25% | 83 |
|
|
2013
Q2 | $120M | Buy |
+555,382
| New | +$119M | 0.24% | 88 |
|
Other funds holding BIIB
VCM
VPM
BlackRock's BIIB Position: Q1 2026 in Review
BlackRock increased its Biogen (BIIB) stake by 7.9% in Q1 2026, buying an estimated $214M and bringing the position to 15,974,601 shares worth $2.93B. The position accounts for 0.05% of the portfolio, ranked #310.
BlackRock first reported a position in BIIB in Q2 2013 and has held it in 52 quarters since. The position peaked at $5.83B in Q3 2018. 1,002 funds tracked by Wall St. Rank hold BIIB as of Q1 2026.
- BlackRock held 15,974,601 shares of Biogen worth $2.93B as of Q1 2026.
- BlackRock bought 1,163,231 Biogen shares in Q1 2026, an estimated $214M.
- Biogen made up 0.05% of BlackRock's portfolio in Q1 2026, its #310 holding.
- BlackRock first reported a position in Biogen in Q2 2013 and has held it in 52 quarters since.
- BlackRock's Biogen position peaked at $5.83B in Q3 2018.
- 1,002 funds tracked by Wall St. Rank held Biogen as of Q1 2026.
Based on BlackRock's 13F filing for Q1 2026, filed 13 May 2026.