• Biogen 2024 shares outstanding were 0.146B, a 0.21% increase from 2023.
• Biogen 2023 shares outstanding were 0.146B, a 0.27% decline from 2022.
• Biogen 2022 shares outstanding were 0.146B, a 2.41% decline from 2021.

Shares outstanding can be defined as the number of shares held by shareholders (including insiders) assuming conversion of all convertible debt, securities, warrants and options. This metric excludes the company's treasury shares.