BIOGEN INC. — Director's Dealing 2019

May 2, 2019

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: BIOGEN INC. (BIIB)
CIK: 0000875045
Period of Report: 2019-04-30

Reporting Person: DENNER ALEXANDER J (Director)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2019-04-30	Common Stock	P	50342	$229.25	Acquired	575000	Indirect
2019-05-01	Common Stock	P	30000	$229.46	Acquired	605000	Indirect
2019-05-02	Common Stock	P	38000	$231.24	Acquired	643000	Indirect

Holdings (Non-Derivative)

Security	Shares	Ownership
Common Stock	10909	Direct

Footnotes

F1: Dr. Denner disclaims beneficial ownership of the shares being reported on this Form 4 except to the extent of his pecuniary interest therein.

F2: Sarissa Capital Management LP ("Sarissa Capital") is the investment advisor to certain investment funds, including the funds that directly beneficially own the securities reported herein (the "Sarissa Funds"). Alexander Denner is the Chief Investment Officer of Sarissa Capital and controls the ultimate general partner of the Sarissa Funds. By virtue of the foregoing, Dr. Denner may be deemed to indirectly beneficially own (as that term is defined in Rule 13d-3 of the Securities Exchange Act of 1934, as amended) the shares that the Sarissa Funds directly beneficially own.