Biogen annual shares outstanding
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
Biogen Shares Outstanding History (BIIB)
Biogen reported 146.8M shares outstanding at the end of fiscal 2025.
View full Biogen company overviewBiogen annual shares outstanding history
| Fiscal year | Period ended | Shares outstanding | Change | Growth |
|---|---|---|---|---|
| 2025 | 2025-12-31 | 146.8M | 1.0M | +0.69% |
| 2024 | 2024-12-31 | 145.8M | 900,000 | +0.62% |
| 2023 | 2023-12-31 | 144.9M | 900,000 | +0.63% |
| 2022 | 2022-12-31 | 144.0M | −3.0M | −2.04% |
| 2021 | 2021-12-31 | 147.0M | −5.4M | −3.54% |
| 2020 | 2020-12-31 | 152.4M | −21.8M | −12.51% |
| 2019 | 2019-12-31 | 174.2M | −23.0M | −11.66% |
| 2018 | 2018-12-31 | 197.2M | −14.3M | −6.76% |
| 2017 | 2017-12-31 | 211.5M | −4.4M | −2.04% |
| 2016 | 2016-12-31 | 215.9M | −2.7M | −1.24% |
| 2015 | 2015-12-31 | 218.6M | −16.0M | −6.82% |
| 2014 | 2014-12-31 | 234.6M | −1.7M | −0.73% |
| 2013 | 2013-12-31 | 236.3M | −250,000 | −0.11% |
| 2012 | 2012-12-31 | 236.6M | −5.5M | −2.29% |
| 2011 | 2011-12-31 | 242.1M | 1.6M | +0.66% |
| 2010 | 2010-12-31 | 240.5M | 240.3M | +87414.51% |
| 2009 | 2009-12-31 | 274,855 | −287.8M | −99.90% |
| 2008 | 2008-12-31 | 288.0M | — | — |
Biogen quarterly shares outstanding
Q4.08
Q4.09
Q4.10
Q4.11
Q4.12
Q4.13
Q4.14
Q4.15
Q4.16
Q4.17
Q4.18
Q4.19
Q4.20
Q4.21
Q4.22
Q4.23
Q4.24
Q4.25
| Fiscal quarter | Period ended | Shares outstanding | Change | YoY change |
|---|---|---|---|---|
| Q4 2025 | 2025-12-31 | 146.8M | −200,000 | −0.14% |
| Q4 2024 | 2024-12-31 | 145.8M | −6.6M | −4.33% |
| Q4 2023 | 2023-12-31 | 144.9M | −29.3M | −16.82% |
| Q4 2022 | 2022-12-31 | 144.0M | −53.2M | −26.98% |
| Q4 2021 | 2021-12-31 | 147.0M | −64.5M | −30.50% |
| Q4 2020 | 2020-12-31 | 152.4M | −63.5M | −29.41% |
| Q4 2019 | 2019-12-31 | 174.2M | −44.4M | −20.31% |
| Q4 2018 | 2018-12-31 | 197.2M | −37.4M | −15.94% |
| Q4 2017 | 2017-12-31 | 211.5M | −24.8M | −10.51% |
| Q4 2016 | 2016-12-31 | 215.9M | −20.7M | −8.74% |
| Q4 2015 | 2015-12-31 | 218.6M | −23.5M | −9.71% |
| Q4 2014 | 2014-12-31 | 234.6M | −5.9M | −2.47% |
| Q4 2013 | 2013-12-31 | 236.3M | 236.1M | +85884.25% |
| Q4 2012 | 2012-12-31 | 236.6M | −51.5M | −17.87% |
| Q4 2011 | 2011-12-31 | 242.1M | — | — |
| Q4 2010 | 2010-12-31 | 240.5M | — | — |
| Q4 2009 | 2009-12-31 | 274,855 | — | — |
| Q4 2008 | 2008-12-31 | 288.0M | — | — |
Biogen shares outstanding trends
Over the last five reported fiscal years, Biogen's shares outstanding moved from 152.4M to 146.8M, a change of −5.6M. The latest reported quarter, Q4 2025, shows 146.8M.
About the metric
What shares outstanding means
Shares outstanding is the number of common shares held by investors at a reporting-period end. The count can change because of stock issuance, repurchases, conversions, acquisitions, or stock splits.
Calculation and source
SEC-reported period-end shares
TickerStat displays period-end common shares from SEC filings and adjusts older values to the current share basis when SEC-reported stock-split conversion ratios are available. Values remain as reported when no split ratio is available. Fiscal periods can differ from calendar years, so exact period-end dates are included.
Review Biogen filings at SEC.gov ↗