BIIB

SEC source: 0001127602-21-007000 · form4.xml · derivative · entry 1

Sandrock Alfred · CIK 0001577061 · EVP, Research & Development

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 14,500

Underlying: Common Stock · 14,500 shares

Expires 2024-02-18

F1 · derivative.exercise_date: 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]).

SEC source: 0001127602-21-006995 · form4.xml · derivative · entry 1

MCDONNELL MICHAEL R · CIK 0001121897 · EVP, Chief Financial Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 14,500

Underlying: Common Stock · 14,500 shares

Expires 2024-02-18

F1 · derivative.exercise_date: 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]).

SEC source: 0001127602-21-006982 · form4.xml · derivative · entry 1

Guindo Chirfi · CIK 0001722753 · EVP Glob. Prod Strat and Comm

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 14,500

Underlying: Common Stock · 14,500 shares

Expires 2024-02-18

F1 · derivative.exercise_date: 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]).

SEC source: 0001127602-21-006986 · form4.xml · derivative · entry 1

Kramer Robin · CIK 0001609222 · SVP, Chief Accounting Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 2,900

Underlying: Common Stock · 2,900 shares

Expires 2024-02-18

F1 · derivative.exercise_date: 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]).

SEC source: 0001127602-21-006976 · form4.xml · derivative · entry 1

Gregory Ginger · CIK 0001545716 · EVP, Human Resources

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 10,150

Underlying: Common Stock · 10,150 shares

Expires 2024-02-18

F1 · derivative.exercise_date: 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]).

SEC source: 0001127602-21-006974 · form4.xml · derivative · entry 1

Galdes Alphonse · CIK 0001789471 · EVP Pharmaceutical Oper & Tech

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 10,870

Underlying: Common Stock · 10,870 shares

Expires 2024-02-18

F1 · derivative.exercise_date: 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]).

SEC source: 0001127602-21-006970 · form4.xml · derivative · entry 1

ALEXANDER SUSAN H · CIK 0001263839 · EVP Chief Legal Off & Corp Sec

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 10,870

Underlying: Common Stock · 10,870 shares

Expires 2024-02-18

F1 · derivative.exercise_date: 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]).

SEC source: 0001127602-21-006281 · form4.xml · derivative · entry 13

Vounatsos Michel · CIK 0001672709 · Director · Chief Executive Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 25,122

Underlying: Common Stock · 7,221 shares

Expires 2023-02-12

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

F2 · derivative.exercise_date: 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]).

SEC source: 0001127602-21-006281 · form4.xml · derivative · entry 12

Vounatsos Michel · CIK 0001672709 · Director · Chief Executive Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 32,343

Underlying: Common Stock · 5,337 shares

Expires 2023-02-12

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F2 · derivative.exercise_date: 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]).

SEC source: 0001127602-21-006281 · form4.xml · derivative · entry 11

Vounatsos Michel · CIK 0001672709 · Director · Chief Executive Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 12,526

Underlying: Common Stock · 7,263 shares

Expires 2022-02-12

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

F2 · derivative.exercise_date: 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]).

SEC source: 0001127602-21-006281 · form4.xml · derivative · entry 10

Vounatsos Michel · CIK 0001672709 · Director · Chief Executive Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 19,789

Underlying: Common Stock · 5,259 shares

Expires 2022-02-12

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F2 · derivative.exercise_date: 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]).

SEC source: 0001127602-21-006281 · form4.xml · derivative · entry 9

Vounatsos Michel · CIK 0001672709 · Director · Chief Executive Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 6,419 shares

Expires 2021-02-12

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

F2 · derivative.exercise_date: 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]).

SEC source: 0001127602-21-006281 · form4.xml · derivative · entry 8

Vounatsos Michel · CIK 0001672709 · Director · Chief Executive Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 6,419

Underlying: Common Stock · 5,693 shares

Expires 2021-02-12

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F2 · derivative.exercise_date: 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]).

SEC source: 0001127602-21-006281 · form4.xml · nonDerivative · entry 7

Vounatsos Michel · CIK 0001672709 · Director · Chief Executive Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 52,969.286

SEC source: 0001127602-21-006281 · form4.xml · nonDerivative · entry 6

Vounatsos Michel · CIK 0001672709 · Director · Chief Executive Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 55,336.286

SEC source: 0001127602-21-006281 · form4.xml · nonDerivative · entry 5

Vounatsos Michel · CIK 0001672709 · Director · Chief Executive Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 57,669.286

SEC source: 0001127602-21-006281 · form4.xml · nonDerivative · entry 4

Vounatsos Michel · CIK 0001672709 · Director · Chief Executive Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 60,194.286

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

SEC source: 0001127602-21-006281 · form4.xml · nonDerivative · entry 3

Vounatsos Michel · CIK 0001672709 · Director · Chief Executive Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 54,857.286

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

SEC source: 0001127602-21-006281 · form4.xml · nonDerivative · entry 2

Vounatsos Michel · CIK 0001672709 · Director · Chief Executive Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 49,598.286

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

SEC source: 0001127602-21-006281 · form4.xml · nonDerivative · entry 1

Vounatsos Michel · CIK 0001672709 · Director · Chief Executive Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 43,905.286

F1 · kind: 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.

SEC source: 0001127602-21-006274 · form4.xml · derivative · entry 8

Kramer Robin · CIK 0001609222 · SVP, Chief Accounting Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 1,008

Underlying: Common Stock · 289 shares

Expires 2023-02-12

F2 · kind: This represents the difference between the maximum possible number of shares that were eligible for vesting and the actual number that vested.

F1 · derivative.exercise_date: 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]).

SEC source: 0001127602-21-006274 · form4.xml · derivative · entry 7

Kramer Robin · CIK 0001609222 · SVP, Chief Accounting Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 1,297

Underlying: Common Stock · 213 shares

Expires 2023-02-12

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_date: 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]).

SEC source: 0001127602-21-006274 · form4.xml · derivative · entry 6

Kramer Robin · CIK 0001609222 · SVP, Chief Accounting Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 288

Underlying: Common Stock · 166 shares

Expires 2022-02-12

F2 · kind: This represents the difference between the maximum possible number of shares that were eligible for vesting and the actual number that vested.

F1 · derivative.exercise_date: 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]).

SEC source: 0001127602-21-006274 · form4.xml · derivative · entry 5

Kramer Robin · CIK 0001609222 · SVP, Chief Accounting Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 454

Underlying: Common Stock · 120 shares

Expires 2022-02-12

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_date: 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]).

SEC source: 0001127602-21-006274 · form4.xml · nonDerivative · entry 4

Kramer Robin · CIK 0001609222 · SVP, Chief Accounting Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 591.446

SEC source: 0001127602-21-006274 · form4.xml · nonDerivative · entry 3

Kramer Robin · CIK 0001609222 · SVP, Chief Accounting Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 664.446

SEC source: 0001127602-21-006274 · form4.xml · nonDerivative · entry 2

Kramer Robin · CIK 0001609222 · SVP, Chief Accounting Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 706.446

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

SEC source: 0001127602-21-006274 · form4.xml · nonDerivative · entry 1

Kramer Robin · CIK 0001609222 · SVP, Chief Accounting Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 493.446

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

SEC source: 0001127602-21-006278 · form4.xml · derivative · entry 13

Sandrock Alfred · CIK 0001577061 · EVP, Research & Development

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 8,042

Underlying: Common Stock · 2,310 shares

Expires 2023-02-12

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

F2 · derivative.exercise_date: 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]).

SEC source: 0001127602-21-006278 · form4.xml · derivative · entry 12

Sandrock Alfred · CIK 0001577061 · EVP, Research & Development

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 10,352

Underlying: Common Stock · 1,708 shares

Expires 2023-02-12

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F2 · derivative.exercise_date: 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]).

SEC source: 0001127602-21-006278 · form4.xml · derivative · entry 11

Sandrock Alfred · CIK 0001577061 · EVP, Research & Development

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 3,446

Underlying: Common Stock · 1,996 shares

Expires 2022-02-12

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

F2 · derivative.exercise_date: 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]).

SEC source: 0001127602-21-006278 · form4.xml · derivative · entry 10

Sandrock Alfred · CIK 0001577061 · EVP, Research & Development

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 5,442

Underlying: Common Stock · 1,446 shares

Expires 2022-02-12

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F2 · derivative.exercise_date: 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]).

SEC source: 0001127602-21-006278 · form4.xml · derivative · entry 9

Sandrock Alfred · CIK 0001577061 · EVP, Research & Development

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 1,466 shares

Expires 2021-02-12

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

F2 · derivative.exercise_date: 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]).

SEC source: 0001127602-21-006278 · form4.xml · derivative · entry 8

Sandrock Alfred · CIK 0001577061 · EVP, Research & Development

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 1,466

Underlying: Common Stock · 1,300 shares

Expires 2021-02-12

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F2 · derivative.exercise_date: 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]).

SEC source: 0001127602-21-006278 · form4.xml · nonDerivative · entry 7

Sandrock Alfred · CIK 0001577061 · EVP, Research & Development

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 17,738.2101

SEC source: 0001127602-21-006278 · form4.xml · nonDerivative · entry 6

Sandrock Alfred · CIK 0001577061 · EVP, Research & Development

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 18,496.2101

SEC source: 0001127602-21-006278 · form4.xml · nonDerivative · entry 5

Sandrock Alfred · CIK 0001577061 · EVP, Research & Development

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 19,138.2101

SEC source: 0001127602-21-006278 · form4.xml · nonDerivative · entry 4

Sandrock Alfred · CIK 0001577061 · EVP, Research & Development

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 19,715.2101

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

SEC source: 0001127602-21-006278 · form4.xml · nonDerivative · entry 3

Sandrock Alfred · CIK 0001577061 · EVP, Research & Development

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 18,007.2101

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

SEC source: 0001127602-21-006278 · form4.xml · nonDerivative · entry 2

Sandrock Alfred · CIK 0001577061 · EVP, Research & Development

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 16,561.2101

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

SEC source: 0001127602-21-006278 · form4.xml · nonDerivative · entry 1

Sandrock Alfred · CIK 0001577061 · EVP, Research & Development

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 15,261.2101

F1 · kind: 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.

SEC source: 0001127602-21-006270 · form4.xml · derivative · entry 8

Guindo Chirfi · CIK 0001722753 · EVP Glob. Prod Strat and Comm

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 7,634

Underlying: Common Stock · 2,194 shares

Expires 2023-02-12

F2 · kind: This represents the difference between the maximum possible number of shares that were eligible for vesting and the actual number that vested.

F1 · derivative.exercise_date: 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]).

SEC source: 0001127602-21-006270 · form4.xml · derivative · entry 7

Guindo Chirfi · CIK 0001722753 · EVP Glob. Prod Strat and Comm

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 9,828

Underlying: Common Stock · 1,622 shares

Expires 2023-02-12

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_date: 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]).

SEC source: 0001127602-21-006270 · form4.xml · derivative · entry 6

Guindo Chirfi · CIK 0001722753 · EVP Glob. Prod Strat and Comm

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 3,656

Underlying: Common Stock · 2,118 shares

Expires 2022-02-12

F2 · kind: This represents the difference between the maximum possible number of shares that were eligible for vesting and the actual number that vested.

F1 · derivative.exercise_date: 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]).

SEC source: 0001127602-21-006270 · form4.xml · derivative · entry 5

Guindo Chirfi · CIK 0001722753 · EVP Glob. Prod Strat and Comm

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 5,774

Underlying: Common Stock · 1,534 shares

Expires 2022-02-12

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_date: 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]).

SEC source: 0001127602-21-006270 · form4.xml · nonDerivative · entry 4

Guindo Chirfi · CIK 0001722753 · EVP Glob. Prod Strat and Comm

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 6,006

SEC source: 0001127602-21-006270 · form4.xml · nonDerivative · entry 3

Guindo Chirfi · CIK 0001722753 · EVP Glob. Prod Strat and Comm

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 6,483

SEC source: 0001127602-21-006270 · form4.xml · nonDerivative · entry 2

Guindo Chirfi · CIK 0001722753 · EVP Glob. Prod Strat and Comm

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 6,946

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

SEC source: 0001127602-21-006270 · form4.xml · nonDerivative · entry 1

Guindo Chirfi · CIK 0001722753 · EVP Glob. Prod Strat and Comm

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 5,324

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

SEC source: 0001127602-21-006268 · form4.xml · derivative · entry 13

Gregory Ginger · CIK 0001545716 · EVP, Human Resources

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 5,028

Underlying: Common Stock · 1,444 shares

Expires 2023-02-12

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

F2 · derivative.exercise_date: 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]).