ALEXANDER SUSAN H 4

What Happened

• Susan H. Alexander, EVP & Chief Legal Officer of Biogen (BIIB), had restricted stock units convert/exercise into 9,046 shares on Feb 6, 2026 (reported 2026-02-10). The acquisitions are reported as derivative exercises/conversions (code M) at $0.00 per share.
• To satisfy tax withholding obligations (code F), 3,504 of those shares were withheld/sold at $201.18 per share, producing total proceeds of $704,936 (breakdown: 1,059 shares for $213,050; 931 shares for $187,299; 1,514 shares for $304,587). After withholding, she received a net 5,542 shares.

Key Details

• Transaction date: February 6, 2026. Filing date: February 10, 2026 (check official form for timeliness code).
• Acquisition entries: 2,190; 1,940; and 4,916 shares converted/exercised (each reported at $0.00).
• Tax-withholding dispositions: 1,059; 931; and 1,514 shares sold/withheld at $201.18 each, totaling $704,936.
• Shares owned after transaction: not specified in the provided filing excerpt.
• Relevant footnotes: F1 (RSUs vest in 3 equal annual installments starting 2/8/2023), F2 (3 equal annual installments starting 2/7/2024), F3 (3 equal annual installments starting 2/6/2025). These entries reflect scheduled vesting/settlement of RSUs and associated tax withholding.

Context

• This appears to be a routine vesting/settlement of restricted stock units with shares withheld to cover tax liabilities (a net-share settlement), not an open-market sale for investment reasons. Code M indicates conversion/exercise of a derivative and code F indicates payment of tax liability via share withholding.
• Such withholding transactions are common and are primarily administrative (to cover taxes) rather than a direct signal of the insider’s market view.