Ken Fisher's BIIB Position Overview
Ken Fisher (via Fisher Asset Management, LLC) currently holds 293,269 shares of Biogen Inc. (BIIB) worth $51.61 M, representing 0.02% of the portfolio. First purchased in 2013-Q2, this long-term strategic position has been held for 51 quarters.
Based on 13F filings since 2013, Ken Fisher has maintained a long-term strategic position in BIIB, representing a significant commitment to this investment thesis. Largest addition occurred in Q1 2025, adding 118,106 shares. Largest reduction occurred in Q4 2023, reducing 50,021 shares.
Analysis based on 13F filings available since 2013 Q2
Ken Fisher's Biogen (BIIB) Holding Value Over Time
Track share changes against reported price movement
Quarterly Biogen (BIIB) Trades by Ken Fisher
| Report Date | Bought/Sold (Sh.) | % Change | Qtr. End Shares | Reported Price |
|---|---|---|---|---|
| Q4 2025 | +15,984 | Add 5.76% | 293,269 | $175.99 |
| Q3 2025 | -11,852 | Reduce 4.10% | 277,285 | $140.08 |
| Q2 2025 | -9,893 | Reduce 3.31% | 289,137 | $125.59 |
| Q1 2025 | +118,106 | Add 65.28% | 299,030 | $136.84 |
| Q4 2024 | +114,156 | Add 170.97% | 180,924 | $152.92 |
| Q3 2024 | -1,719 | Reduce 2.51% | 66,768 | $193.84 |
| Q2 2024 | +6,943 | Add 11.28% | 68,487 | $231.82 |
| Q1 2024 | -2,234 | Reduce 3.50% | 61,544 | $215.63 |
| Q4 2023 | -50,021 | Reduce 43.96% | 63,778 | $258.77 |
| Q3 2023 | -16,518 | Reduce 12.68% | 113,799 | $257.01 |
| Q2 2023 | -2,500 | Reduce 1.88% | 130,317 | $284.85 |
| Q1 2023 | +322 | Add 0.24% | 132,817 | $278.03 |
| Q4 2022 | +2,034 | Add 1.56% | 132,495 | $276.92 |
| Q3 2022 | -2,387 | Reduce 1.80% | 130,461 | $267.00 |
| Q2 2022 | +504 | Add 0.38% | 132,848 | $203.94 |
| Q1 2022 | +310 | Add 0.23% | 132,344 | $210.60 |
| Q4 2021 | +23,545 | Add 21.70% | 132,034 | $239.92 |
| Q3 2021 | +3,414 | Add 3.25% | 108,489 | $282.99 |
| Q2 2021 | +6,497 | Add 6.59% | 105,075 | $346.27 |
| Q1 2021 | -6 | Reduce 0.01% | 98,578 | $279.75 |
| Q4 2020 | +4,648 | Add 4.95% | 98,584 | $244.86 |
| Q3 2020 | +1,031 | Add 1.11% | 93,936 | $283.68 |
| Q2 2020 | -720 | Reduce 0.77% | 92,905 | $267.55 |
| Q1 2020 | +2,848 | Add 3.14% | 93,625 | $316.38 |
| Q4 2019 | -33,205 | Reduce 26.78% | 90,777 | $296.73 |
| Q3 2019 | +4,012 | Add 3.34% | 123,982 | $232.82 |
| Q2 2019 | -15,901 | Reduce 11.70% | 119,970 | $233.87 |
| Q1 2019 | -2,081 | Reduce 1.51% | 135,871 | $236.38 |
| Q4 2018 | +7,771 | Add 5.97% | 137,952 | $300.92 |
| Q3 2018 | +2,068 | Add 1.61% | 130,181 | $353.31 |
| Q2 2018 | +4,704 | Add 3.81% | 128,113 | $290.24 |
| Q1 2018 | +24,129 | Add 24.30% | 123,409 | $273.82 |
| Q4 2017 | -8,584 | Reduce 7.96% | 99,280 | $318.57 |
| Q3 2017 | -1,265 | Reduce 1.16% | 107,864 | $313.12 |
| Q2 2017 | -285 | Reduce 0.26% | 109,129 | $271.36 |
| Q1 2017 | +7,527 | Add 7.39% | 109,414 | $273.42 |
| Q4 2016 | +1,169 | Add 1.16% | 101,887 | $283.58 |
| Q3 2016 | -1,201 | Reduce 1.18% | 100,718 | $313.03 |
| Q2 2016 | +11,514 | Add 12.74% | 101,919 | $252.54 |
| Q1 2016 | -20,070 | Reduce 18.17% | 90,405 | $268.50 |
| Q4 2015 | -1,973 | Reduce 1.75% | 110,475 | $306.35 |
| Q3 2015 | +31,516 | Add 38.94% | 112,448 | $291.81 |
| Q2 2015 | -126 | Reduce 0.16% | 80,932 | $403.94 |
| Q1 2015 | +1,804 | Add 2.28% | 81,058 | $422.24 |
| Q4 2014 | +797 | Add 1.02% | 79,254 | $339.45 |
| Q3 2014 | -10,428 | Reduce 11.73% | 78,457 | $330.81 |
| Q2 2014 | +70,619 | Add 386.61% | 88,885 | $315.31 |
| Q1 2014 | +16,228 | Add 796.27% | 18,266 | $305.87 |
| Q4 2013 | +264 | Add 14.88% | 2,038 | $279.69 |
| Q3 2013 | +7 | Add 0.40% | 1,774 | $240.70 |
| Q2 2013 | +1,767 | Add 0.00% | 1,767 | $215.05 |
Ken Fisher's Biogen Investment FAQs
Ken Fisher first purchased Biogen Inc. (BIIB) in Q2 2013, acquiring 1,767 shares, as reported in their 13F filing for that period. Note: Analysis reflects filings available since Q2 2013; earlier records may be incomplete.
Ken Fisher has held Biogen Inc. (BIIB) for 51 quarters since Q2 2013.
Ken Fisher's largest addition to Biogen Inc. (BIIB) was in Q1 2025, adding 299,030 shares worth $40.92 M.
According to the latest 13F filing for Q4 2025, Ken Fisher's firm, Fisher Asset Management, LLC, owns 293,269 shares of Biogen Inc. (BIIB), valued at approximately $51.61 M.
As of the Q4 2025 filing, Biogen Inc. (BIIB) represents approximately 0.02% of Ken Fisher's publicly disclosed stock portfolio, making it one of their key holdings.
Ken Fisher's peak holding in Biogen Inc. (BIIB) was 299,030 shares, as reported at the end of Q1 2025.