X0609 4 2026-06-09 0000875045 BIOGEN INC. BIIB 0002038687 Minor Lloyd false 225 BINNEY STREET CAMBRIDGE MA 02142 1 0 Common Stock 2026-06-09 4 A 0 1505 0 A 3875 D The restricted stock units vest on the earlier of (i) the next annual meeting or (ii) the anniversary of the date of grant of June 9, 2026. /s/ Wendell Taylor, attorney-in-fact for Dr. Minor 2026-06-11