Biogen (BIIB) Shares Outstanding (Diluted) (2009 - 2026)
Biogen's Weighted Average Shares Outstanding (Diluted) came in at 147.8 million for Q3 2026, up 0.5% from 147.1 million a year earlier but down 0.6% from the prior quarter.
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Analysis
Biogen (BIIB) Shares Outstanding (Diluted) (2009 - 2026) Analysis & Trends
For FY2025, Biogen's Weighted Average Shares Outstanding (Diluted) was 147.1 million, up 0.8% from FY2024.
- Weighted Average Shares Outstanding (Diluted) carries a five-year compound annual growth rate of -1.8% (FY2020 to FY2025).
- Going back by year, Weighted Average Shares Outstanding (Diluted) was 145.9 million in FY2024 (+0.2%), 145.6 million in FY2023 (-0.3%), 146 million in FY2022 (-2.4%) and 149.6 million in FY2021 (-7.3%).
- The five-year range for quarterly Weighted Average Shares Outstanding (Diluted) is 144.8 million (Q3 2022) to 149.6 million (Q4 2021).
- Year-over-year, Weighted Average Shares Outstanding (Diluted) has increased for 11 consecutive quarters, with growth averaging 0.7% over the last eight quarters.
- The fastest year-over-year change in Weighted Average Shares Outstanding (Diluted) over five years came in Q2 2026 (growth of 1.4%), and the weakest in Q4 2021 (a decline of 7.3%).
- Business Quant data shows BIIB's Weighted Average Shares Outstanding (Diluted) at 148.7 million (Q2 2026), 148.4 million (Q1 2026) and 147.1 million (Q4 2025) in the three quarters before Q3 2026.
Peer Set
Peer Comparison
| # | Company | Market Cap | Enterprise Value | Gross Profit (Qtr) | Shares Outstanding (Dil.) (Qtr) |
|---|---|---|---|---|---|
| 1 | Eli Lilly | 1,359.75 Bn | 1,333.37 Bn | 20.46 Bn | 893.40 Mn |
| 2 | Johnson & Johnson | 688.76 Bn | 608.62 Bn | 17.30 Bn | 2.45 Bn |
| 3 | AbbVie | 521.69 Bn | 489.75 Bn | 13.12 Bn | 1.77 Bn |
| 4 | Merck | 364.31 Bn | 327.31 Bn | 13.19 Bn | 2.48 Bn |
| 5 | Novartis Ag | 306.35 Bn | 279.93 Bn | - | 1.96 Bn |
| 6 | Astrazeneca | 285.96 Bn | 259.56 Bn | 13.26 Bn | 1.56 Bn |
| 7 | Amgen | 251.88 Bn | 203.53 Bn | 7.58 Bn | 546.00 Mn |
| 8 | Gilead Sciences | 208.59 Bn | 183.61 Bn | 6.73 Bn | 1.25 Bn |
| 9 | Pfizer | 164.73 Bn | 112.38 Bn | 12.56 Bn | 5.75 Bn |
| 10 | Biogen | 37.46 Bn | 26.77 Bn | 2.06 Bn | 147.80 Mn |
Historic Data
Download Data
Historic Data
| Date | Value |
|---|---|
| Sep 30, 2026 | 147.80 Mn |
| Jun 30, 2026 | 148.70 Mn |
| Mar 31, 2026 | 148.40 Mn |
| Dec 31, 2025 | 147.10 Mn |
| Sep 30, 2025 | 147.10 Mn |
| Jun 30, 2025 | 146.70 Mn |
| Mar 31, 2025 | 146.60 Mn |
| Dec 31, 2024 | 145.90 Mn |
| Sep 30, 2024 | 146.10 Mn |
| Jun 30, 2024 | 145.90 Mn |
| Mar 31, 2024 | 145.90 Mn |
| Dec 31, 2023 | 145.60 Mn |
| Sep 30, 2023 | 144.80 Mn |
| Jun 30, 2023 | 145.50 Mn |
| Mar 31, 2023 | 145.20 Mn |
| Dec 31, 2022 | 146.00 Mn |
| Sep 30, 2022 | 144.80 Mn |
| Jun 30, 2022 | 146.20 Mn |
| Mar 31, 2022 | 147.60 Mn |
| Dec 31, 2021 | 149.60 Mn |
API Access
Biogen Shares Outstanding (Diluted) API
Pull this series into your own models, spreadsheets and apps with the Business Quant
Historical Metrics API. The request below matches the chart above — change the
frequency, period or values and it follows. Swap YOUR_API_KEY for your own key.
https://data.businessquant.com/historic?slug=shares-outstanding-diluted&ticker=BIIB&period=max&api_key=YOUR_API_KEYimport requests
url = "https://data.businessquant.com/historic"
params = {"slug": "shares-outstanding-diluted", "ticker": "BIIB", "period": "max", "api_key": "YOUR_API_KEY"}
data = requests.get(url, params=params).json()const res = await fetch("https://data.businessquant.com/historic?slug=shares-outstanding-diluted&ticker=BIIB&period=max&api_key=YOUR_API_KEY");
const data = await res.json();