Biogen Inc.
BIIB- Exchange
- Nasdaq
- Industry
- Biological Products, (No Diagnostic Substances)
- SEC CIK
- 0000875045
No open-market purchases or sales by Biogen Inc. insiders were filed in the last 90 days; 1,049 institutions reported holding it in 13F filings for Q2 2026, worth $30.7B in total; no superinvestor holds it.
Key figures
- Market capClose on Nov 11, 2026
- $37.5B
- Insider buysOpen market, last 90 days
- 0
- Insider sellsOpen market, last 90 days
- 0
- 13F holdersQ2 2026, +40 vs. previous quarter
- 1,049
- 13F valueReported value at the end of Q2 2026
- $30.7B
- Superinvestors holdingAt the end of Q2 2026
- 0
Price chart
Financials
See financial statementsFrom SEC filings, in USD.
- Revenue, FY2025
- $9.89B
- +2.2% year over year
- Net income, FY2025
- $1.29B
- −20.8% year over year
- Free cash flow, FY2025
- $2.05B
- −24.7% year over year
- Revenue, Q3 FY2026
- $2.80B
- +10.6% year over year
Revenue flow, FY2025
Green is profit; orange is costs, expenses and taxes. Percentages are shares of revenue.
Short interest
See short dataFrom FINRA, settlement date Oct 30, 2026.
- Short interest
- 5.45M
- Shares sold short
- Change
- −47.3K
- −0.9% vs. previous
- Days to cover
- 3.96
- At average daily volume
Superinvestors holding BIIB, Q2 2026
Go to the superinvestors tabNo superinvestor reported holding BIIB at the end of Q2 2026.
Latest insider trades
See all insider tradesOpen-market purchases and sales by Biogen Inc. insiders from Form 4, newest first.
| Filed (ET) | Trade date | Filing delay | Insider | Transaction | Shares | Avg price | Value | Holding change | Flags |
|---|---|---|---|---|---|---|---|---|---|
| Aug 5, 2026 (view filing)4:03 PM ET | Aug 3-4 | 2 days | Minor LloydDirector | SSale | −1.19K | $202.15 | −$239.7K | −30.6%2.69K after | 2 lots10b5-1 |
| Feb 17, 2026 (view filing) | Feb 12 | 5 days | Murphy NicoleHead of Pharm Ops and Tech | PPurchase | +3 | $195.04 | +$585.12 | 0.0%19.6K after | |
| Feb 10, 2026 (view filing) | Feb 9 | 1 day | Singhal PriyaHead of Development | SSale | −2.66K | $199.83 | −$531.5K | −24.9%8.04K after | 10b5-1 |
| Feb 3, 2026 (view filing) | Feb 2 | 1 day | Singhal PriyaHead of Development | SSale | −748 | $179.30 | −$134.1K | −10.7%6.27K after | 10b5-1 |
| Sep 2, 2025 (view filing) | Sep 2 | Same day | Singhal PriyaHead of Development | SSale | −517 | $133.55 | −$69.0K | −8.2%5.77K after | 10b5-1 |
| Jul 16, 2025 (view filing) | Jul 8 | 8 daysLate | Izzar RachidHead of Global Product Strat. | SSale | −2.22K | $135.00 | −$300.1K | −26.0%6.33K after | 10b5-1 |
| May 20, 2025 (view filing) | May 19 | 1 day | Singhal PriyaHead of Development | SSale | −3.81K | $126.25 | −$480.5K | −41.2%5.43K after | 10b5-1 |
| May 5, 2025 (view filing) | May 2 | 3 days | Dorsa CarolineDirector | PPurchase | +1.24K | $122.72 | +$151.6K | +4.6%27.8K after | |
| Mar 10, 2025 (view filing) | Mar 7 | 3 days | Sherwin Stephen ADirector | SSale | −8.76K | $150.02 | −$1.31M | −43.6%11.3K after | 10b5-1 |
| Dec 9, 2024 (view filing) | Dec 9 | Same day | Singhal PriyaHead of Development | SSale | −110 | $157.21 | −$17.3K | −2.0%5.43K after | 10b5-1 |
Top 10 13F holders, Q2 2026
See all 1,049 holdersThe largest institutional positions in Biogen Inc. at the end of Q2 2026; share changes are against Q1 2026.
| Institution | Shares | Value | % of portfolio | Change in shares | Action |
|---|---|---|---|---|---|
| FMR LLC | 18,217,239 | $3.94B | 0.17% | +5,409,698+42.2% | Added |
| BlackRock, Inc. | 15,985,736 | $3.45B | 0.05% | +11,135+0.1% | Added |
| Primecap Management Co | 15,154,606 | $3.27B | 1.94% | +396,999+2.7% | Added |
| Vanguard Capital Management LLC | 9,651,117 | $2.09B | 0.04% | +113,700+1.2% | Added |
| State Street Corp | 7,344,327 | $1.59B | 0.05% | +176,405+2.5% | Added |
| Vanguard Portfolio Management LLC | 6,604,936 | $1.43B | 0.06% | +73,209+1.1% | Added |
| Geode Capital Management, LLC | 4,449,295 | $957.9M | 0.05% | +106,693+2.5% | Added |
| Wellington Management Group LLP | 3,117,469 | $673.6M | 0.12% | +155,828+5.3% | Added |
| Norges Bank | 2,580,033 | $557.4M | 0.06% | +2,580,033 | New |
| Morgan Stanley | 2,411,271 | $521.0M | 0.03% | +240,331+11.1% | Added |
Holders of 5% or more of BIIB
See all 5 holders and filingsHolders whose latest Schedule 13D or 13G filing reports 5% or more of Biogen Inc..
| Holder | Latest form | Stake | Change | First filed | Latest filing | Filing |
|---|---|---|---|---|---|---|
| FMR LLC | 13G/A | 12.40%18.3M shares | +1.10 ppfrom 11.30% | Feb 5, 20264 filings | Aug 6, 2026 | SEC |
| Primecap Management Co | 13G/A | 10.20%15.0M shares | – | Feb 12, 20215 filings | Nov 13, 2025 | SEC |
| BlackRock, Inc. | 13G/A | 8.50%12.5M shares | – | Apr 17, 20251 filing | Apr 17, 2025 | SEC |
| Vanguard Capital Management LLC | 13G | 7.48%11.0M shares | New | Apr 29, 20261 filing | Apr 29, 2026 | SEC |
| State Street Corp | 13G | 5.10%7.57M shares | +0.10 ppfrom 5.00% | Oct 16, 20243 filings | Nov 10, 2026 | SEC |
Politician trades
All politician trades in BIIB12 members of Congress reported 32 trades in Biogen Inc. since 2020. Newest filings:
| Filed | Politician | Type | Amount |
|---|---|---|---|
| Oct 7, 2026 |  Maria Elvira Salazar House · FL | Sell (partial) | $1K-$15K |
| Sep 1, 2026 |  Kevin Hern House · OK | Sell | $1K-$15K |
| Jul 21, 2026 |  Alan Armstrong Senate · OK | Buy | $1K-$15K |
| Jul 7, 2026 | Maria Elvira Salazar House · FL | Sell | $15K-$50K |
| Jul 2, 2026 |  Gilbert Ray Cisneros, Jr. House · CA | Buy | $1K-$15K |
House · FL · Oct 7, 2026
Sell (partial)$1K-$15K
House · OK · Sep 1, 2026
Sell$1K-$15K
Senate · OK · Jul 21, 2026
Buy$1K-$15K
House · FL · Jul 7, 2026
Sell$15K-$50K
House · CA · Jul 2, 2026
Buy$1K-$15K