Insider at

04

Insider transactions

05
0 buys (P) 0 sells (S) Net: $0 + 19 non-open-market transactions below last 12 months, based on the transactions shown below

Price change vs current quote, split-adjusted for corporate actions since the filing — not benchmarked, not annualized, not size-weighted

No open-market trades on record; showing all filings.

DateTickerCodeSharesPriceValue Owned afterΔ ownA/Dvs now
Feb. 13, 2026 BIIB A 8,450 · · 8,450 Direct · Acquired (price as of 2026-10-02)
Feb. 6, 2026 BIIB M 1,873 · · 3,747 Direct -33.33% Disposed (price as of 2026-10-02)
Feb. 6, 2026 BIIB M 1,385 · · 1,385 Direct -50.00% Disposed (price as of 2026-10-02)
Feb. 6, 2026 BIIB F 584 $201.18 $117,489 4,058 Direct -12.58% Disposed 9.3% (price as of 2026-10-02)
Feb. 6, 2026 BIIB M 1,873 · · 4,642 Direct +67.64% Acquired (price as of 2026-10-02)
Feb. 6, 2026 BIIB F 407 $201.18 $81,880 2,769 Direct -12.81% Disposed 9.3% (price as of 2026-10-02)
Feb. 6, 2026 BIIB M 1,385 · · 3,176 Direct +77.33% Acquired (price as of 2026-10-02)
Oct. 31, 2025 BIIB M 695 · · 695 Direct -50.00% Disposed (price as of 2026-10-02)
Oct. 31, 2025 BIIB F 337 $154.27 $51,989 1,791 Direct -15.84% Disposed 42.5% (price as of 2026-10-02)
Oct. 31, 2025 BIIB M 695 · · 2,128 Direct +48.50% Acquired (price as of 2026-10-02)
Feb. 7, 2025 BIIB M 1,385 · · 2,770 Direct -33.33% Disposed (price as of 2026-10-02)
Feb. 7, 2025 BIIB F 443 $141.35 $62,618 1,433 Direct -23.61% Disposed 55.6% (price as of 2026-10-02)
Feb. 7, 2025 BIIB M 1,385 · · 1,876 Direct +282.08% Acquired (price as of 2026-10-02)
Feb. 6, 2025 BIIB A 5,620 · · 5,620 Direct · Acquired (price as of 2026-10-02)
Nov. 1, 2024 BIIB M 695 · · 1,390 Direct -33.33% Disposed (price as of 2026-10-02)
Nov. 1, 2024 BIIB F 204 $173.79 $35,453 491 Direct -29.35% Disposed 26.5% (price as of 2026-10-02)
Nov. 1, 2024 BIIB M 695 · · 695 Direct · Acquired (price as of 2026-10-02)
Feb. 7, 2024 BIIB A 4,155 · · 4,155 Direct · Acquired (price as of 2026-10-02)
Nov. 1, 2023 BIIB A 2,085 · · 2,085 Direct · Acquired (price as of 2026-10-02)

P = Open-market purchase · S = Sale · A = Grant/award · M = Option exercise · G = Gift · F = Tax withholding

Insider transactions are not a recommendation; sales are often driven by liquidity or tax reasons.

Derivative holdings (Form 4 Table II) Options, RSUs and convertible securities reported on Form 4 Table II.

06
DateTickerSecurityUnderlying Exercise priceExpirationSharesA/D
Feb. 13, 2026 BIIB Restricted Stock Unit Common Stock (8,450) $0.00 Feb. 13, 2029 8,450 Acquired
Feb. 6, 2026 BIIB Restricted Stock Unit Common Stock (1,873) $0.00 Feb. 6, 2028 1,873 Disposed
Feb. 6, 2026 BIIB Restricted Stock Unit Common Stock (1,385) $0.00 Feb. 7, 2027 1,385 Disposed
Oct. 31, 2025 BIIB Restricted Stock Unit Common Stock (695) $0.00 Nov. 1, 2026 695 Disposed
Feb. 7, 2025 BIIB Restricted Stock Unit Common Stock (1,385) $0.00 Feb. 7, 2027 1,385 Disposed
Feb. 6, 2025 BIIB Restricted Stock Unit Common Stock (5,620) $0.00 Feb. 6, 2028 5,620 Acquired
Nov. 1, 2024 BIIB Restricted Stock Unit Common Stock (695) $0.00 Nov. 1, 2026 695 Disposed
Feb. 7, 2024 BIIB Restricted Stock Unit Common Stock (4,155) $0.00 Feb. 7, 2027 4,155 Acquired
Nov. 1, 2023 BIIB Restricted Stock Unit Common Stock (2,085) $0.00 Nov. 1, 2026 2,085 Acquired

Exercise/conversion price is blank when not applicable (e.g. RSUs).

Initial ownership (Form 3) 1 holding

07

Securities held when first becoming an insider, per SEC Form 3.

DateTickerSecuritySharesOwnership
Oct. 12, 2023 BIIB Common Stock 0 Direct