BIOGEN INC. — Director's Dealing 2021

Feb 17, 2021

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: BIOGEN INC. (BIIB)
CIK: 0000875045
Period of Report: 2021-02-12

Reporting Person: Galdes Alphonse (EVP Pharmaceutical Oper & Tech)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2021-02-12	Common Stock	F	253	$278.03	Disposed	3192.229	Direct
2021-02-12	Common Stock	M	286	—	Acquired	3478.229	Direct
2021-02-12	Common Stock	M	327	—	Acquired	3805.229	Direct
2021-02-12	Common Stock	M	960	—	Acquired	4765.229	Direct
2021-02-12	Common Stock	F	84	$278.03	Disposed	4681.229	Direct
2021-02-12	Common Stock	F	96	$278.03	Disposed	4585.229	Direct
2021-02-12	Common Stock	F	282	$278.03	Disposed	4303.229	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2021-02-12	Restricted Stock Unit	$0	M	286	Disposed	2021-02-12	Common Stock (286)	Direct
2021-02-12	Restricted Stock Unit	$0	J	322	Disposed	2021-02-12	Common Stock (322)	Direct
2021-02-12	Restricted Stock Unit	$0	M	327	Disposed	2022-02-12	Common Stock (327)	Direct
2021-02-12	Restricted Stock Unit	$0	J	451	Disposed	2022-02-12	Common Stock (451)	Direct
2021-02-12	Restricted Stock Unit	$0	M	960	Disposed	2023-02-12	Common Stock (960)	Direct
2021-02-12	Restricted Stock Unit	$0	J	1298	Disposed	2023-02-12	Common Stock (1298)	Direct

Holdings (Non-Derivative)

Security	Shares	Ownership
Common Stock	969.366	Indirect

Footnotes

F1: Represents shares withheld to satisfy the withholding tax liability due upon the vesting of shares, as previously disclosed by reporting person on January 29, 2021.

F2: The number of RSUs reported represents the maximum possible number of shares that are eligible for vesting, which is 200% of the number of shares at target payout. One-third of these RSUs are eligible to vest on each of the first three anniversaries of the grant date. The actual number of shares that will vest on each vesting date will be determined by comparing the price of Biogen common stock on such vesting date to the price on the grant date (i.e., number of vested shares = number of shares at target payout times [the 30-day average closing stock price ending on the vesting date divided by the 30-day average closing stock price following and including the grant date]).

F3: This represents the difference between the maximum possible number of shares that were eligible for vesting and the actual number that vested.