Save your place

Sign in to WhoBought

Please try again later.

Ken Fisher's Biogen Inc. (BIIB) position

Yes: as of Q1 2026, Ken Fisher holds 313K shares of BIIB worth $57M (0.0% of the disclosed portfolio). Held since at least Q1 2021; that opening coverage snapshot is not counted as a purchase.
View full portfolio →
Current value
$57M
Shares held
313K
% of portfolio
0.0%
Est. average buy price (i)
$169.32
est. since Q3 2022
Quarter-end price
$183.33

Estimated trade prices

Average price in quarters with purchases
$170.11
Average prices in quarters with sales
  • Q3 2025: $135.22 (12K shares sold)
  • Q2 2025: $124.60 (10K shares sold)
  • Q3 2024: $209.21 (2K shares sold)
  • Q1 2024: $234.20 (2K shares sold)
  • Q4 2023: $245.62 (50K shares sold)
  • Q3 2023: $267.47 (17K shares sold)
  • Q2 2023: $297.84 (2K shares sold)

BIIB price vs Fisher's position

1Y 3Y 5Y MAX
Dates
$100$200$40020222023202420252026Added 3K shares (3.2%) · Q3 2021. Average closing price $327.75 · Price range $282.99–$369.053KsharespurchasedAdded 24K shares (21.7%) · Q4 2021. Average closing price $257.12 · Price range $223.92–$287.7724KsharespurchasedAdded 310 shares (0.2%) · Q1 2022. Average closing price $217.46 · Price range $193.77–$244.14310sharespurchasedAdded 504 shares (0.4%) · Q2 2022. Average closing price $204.43 · Price range $187.54–$223.02504sharespurchasedAdded 2K shares (1.6%) · Q4 2022. Average closing price $282.44 · Price range $253.67–$306.722KsharespurchasedAdded 322 shares (0.2%) · Q1 2023. Average closing price $276.70 · Price range $256.56–$292.34322sharespurchasedSold 2K shares (1.9%) · Q2 2023. Average closing price $297.84 · Price range $275.25–$318.062KsharessoldSold 17K shares (12.7%) · Q3 2023. Average closing price $267.47 · Price range $253.30–$285.8917KsharessoldSold 50K shares (44.0%) · Q4 2023. Average closing price $245.62 · Price range $222.59–$267.9450KsharessoldSold 2K shares (3.5%) · Q1 2024. Average closing price $234.20 · Price range $212.02–$267.712KsharessoldAdded 7K shares (11.3%) · Q2 2024. Average closing price $217.32 · Price range $190.52–$236.727KsharespurchasedSold 2K shares (2.5%) · Q3 2024. Average closing price $209.21 · Price range $189.07–$236.802KsharessoldAdded 114K shares (171.0%) · Q4 2024. Average closing price $168.67 · Price range $146.47–$191.56114KsharespurchasedAdded 118K shares (65.3%) · Q1 2025. Average closing price $142.96 · Price range $133.43–$153.27118KsharespurchasedSold 10K shares (3.3%) · Q2 2025. Average closing price $124.60 · Price range $113.38–$135.4910KsharessoldSold 12K shares (4.1%) · Q3 2025. Average closing price $135.22 · Price range $122.68–$148.8412KsharessoldAdded 16K shares (5.8%) · Q4 2025. Average closing price $163.32 · Price range $142.19–$182.0716KsharespurchasedAdded 19K shares (6.6%) · Q1 2026. Average closing price $184.10 · Price range $164.42–$201.1819Ksharespurchased
Average closing price · filing quarter
$184.10
Price range · filing quarter
$164.42 – $201.18
Sign in to see who bought

Every quarterly change

Quarter Action Shares change Est. value change Δ Own Shares held Filing date
Q1 2026 Added +19K +$3.6M +6.6% 313K May 5, 2026
Q4 2025 Added +16K +$2.6M +5.8% 293K Feb 9, 2026
Q3 2025 Reduced −12K −$1.6M −4.1% 277K Nov 12, 2025
Q2 2025 Reduced −10K −$1.2M −3.3% 289K Aug 13, 2025
Q1 2025 Added +118K +$17M +65.3% 299K May 14, 2025
Q4 2024 Added +114K +$19M +171.0% 181K Feb 5, 2025
Q3 2024 Reduced −2K −$360K −2.5% 67K Nov 12, 2024
Q2 2024 Added +7K +$1.5M +11.3% 68K Aug 14, 2024
Q1 2024 Reduced −2K −$523K −3.5% 62K May 9, 2024
Q4 2023 Reduced −50K −$12M −44.0% 64K Mar 5, 2024
Q3 2023 Reduced −17K −$4.4M −12.7% 114K Nov 13, 2023
Q2 2023 Reduced −2K −$745K −1.9% 130K Dec 12, 2023
Q1 2023 Added +322 +$89K +0.2% 133K Dec 12, 2023
Q4 2022 Added +2K +$574K +1.6% 132K Feb 3, 2023
Q3 2022 First covered – – – 130K Nov 8, 2022
Q2 2022 Added +504 +$103K +0.4% 133K Aug 9, 2022
Q1 2022 Added +310 +$67K +0.2% 132K May 5, 2022
Q4 2021 Added +24K +$6.1M +21.7% 132K Feb 2, 2022
Q3 2021 Added +3K +$1.1M +3.2% 108K Oct 26, 2021
Q2 2021 First covered – – – 105K Jul 27, 2021
Q1 2021 First covered – – – 99K Apr 27, 2021
Data through Q1 2026 · filed May 5, 2026
21 grouped rows from 21 quarters

More Fisher positions

NVIDIA Corporation(NVDA)
$15.3B
5.2% of portfolio

Apple Inc.(AAPL)
$14.3B
4.9% of portfolio

Alphabet Inc.(GOOGL)
$11.0B
3.8% of portfolio

Microsoft Corporation(MSFT)
$9.6B
3.3% of portfolio

Amazon.com, Inc.(AMZN)
$7.0B
2.4% of portfolio

Caterpillar Inc.(CAT)
$6.9B
2.3% of portfolio

Common questions

Does Ken Fisher own BIIB?

Yes. As of Q1 2026, Ken Fisher disclosed 313K shares of BIIB, worth $57M. All figures come from SEC 13F filings for Q1 2026, the latest disclosed quarter.

When did Ken Fisher buy BIIB?

Ken Fisher held BIIB since at least Q1 2021, when this filing coverage begins; the opening snapshot is not a disclosed purchase. All figures come from SEC 13F filings for Q1 2026, the latest disclosed quarter.

Did Ken Fisher sell BIIB?

The quarter-by-quarter table above shows each sale and reduction Ken Fisher disclosed in BIIB. All figures come from SEC 13F filings for Q1 2026, the latest disclosed quarter.

How many shares of BIIB does Ken Fisher own?

Ken Fisher disclosed 313K shares of BIIB as of Q1 2026. All figures come from SEC 13F filings for Q1 2026, the latest disclosed quarter.

What price did Ken Fisher pay for BIIB?

Ken Fisher began building the BIIB position before our 13F history starts, so an exact average buy price cannot be estimated without understating it. All figures come from SEC 13F filings for Q1 2026, the latest disclosed quarter.

How are the estimated trade prices calculated?

13F filings disclose quarter-end holdings, not trade dates or execution prices. These estimates use each covered quarter's average market price; the add average excludes the opening position and quarters without price data. All figures come from SEC 13F filings for Q1 2026, the latest disclosed quarter.