BIIB

SEC source: 0001127602-20-005772 · form4.xml · derivative · entry 11

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

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 8,485

Underlying: Common Stock · 1,535 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: 0001127602-20-005772 · form4.xml · derivative · entry 10

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

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 2,697 shares

Expires 2020-02-12

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.

F3 · derivative.exercise_date: The restricted stock units will vest in 2 annual installments. One-third will vest on the first anniversary of the grant date and two-thirds will vest on the second anniversary of the grant date.

SEC source: 0001127602-20-005772 · form4.xml · derivative · entry 9

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

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 3,374

Underlying: Common Stock · 1,633 shares

Expires 2021-02-12

F2 · shares: 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: 0001127602-20-005772 · form4.xml · derivative · entry 8

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

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 5,007

Underlying: Common Stock · 1,735 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.

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: 0001127602-20-005772 · form4.xml · derivative · entry 7

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

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 9,650

Underlying: Common Stock · 9,650 shares

Expires 2023-02-12

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: 0001127602-20-005772 · form4.xml · nonDerivative · entry 6

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

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 35,708

SEC source: 0001127602-20-005772 · form4.xml · nonDerivative · entry 5

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

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 36,389

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: 0001127602-20-005772 · form4.xml · nonDerivative · entry 4

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

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 34,854

SEC source: 0001127602-20-005772 · form4.xml · nonDerivative · entry 3

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

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 35,652

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: 0001127602-20-005772 · form4.xml · nonDerivative · entry 2

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

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 32,955

SEC source: 0001127602-20-005772 · form4.xml · nonDerivative · entry 1

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

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 33,711

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: 0001127602-20-005770 · form4.xml · derivative · entry 12

Sandrock Alfred · CIK 0001577061 · EVP, Research & Development

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 12,060

Underlying: Common Stock · 12,060 shares

Expires 2023-02-12

F3 · 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: 0001127602-20-005770 · form4.xml · derivative · entry 11

Sandrock Alfred · CIK 0001577061 · EVP, Research & Development

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 6,888

Underlying: Common Stock · 1,859 shares

Expires 2022-02-12

F4 · shares: This represents the difference between the maximum possible number of shares that were eligible for vesting and the actual number that vested.

F3 · 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: 0001127602-20-005770 · form4.xml · derivative · entry 10

Sandrock Alfred · CIK 0001577061 · EVP, Research & Development

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 8,747

Underlying: Common Stock · 1,583 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.

F3 · 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: 0001127602-20-005770 · form4.xml · derivative · entry 9

Sandrock Alfred · CIK 0001577061 · EVP, Research & Development

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 2,766

Underlying: Common Stock · 1,340 shares

Expires 2021-02-12

F4 · shares: This represents the difference between the maximum possible number of shares that were eligible for vesting and the actual number that vested.

F3 · 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: 0001127602-20-005770 · form4.xml · derivative · entry 8

Sandrock Alfred · CIK 0001577061 · EVP, Research & Development

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 4,106

Underlying: Common Stock · 1,422 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.

F3 · 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: 0001127602-20-005770 · form4.xml · derivative · entry 7

Sandrock Alfred · CIK 0001577061 · EVP, Research & Development

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 2,211 shares

Expires 2020-02-12

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 restricted stock units will vest in 2 annual installments. One-third will vest on the first anniversary of the grant date and two-thirds will vest on the second anniversary of the grant date.

SEC source: 0001127602-20-005770 · form4.xml · nonDerivative · entry 6

Sandrock Alfred · CIK 0001577061 · EVP, Research & Development

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 13,806.2451

SEC source: 0001127602-20-005770 · form4.xml · nonDerivative · entry 5

Sandrock Alfred · CIK 0001577061 · EVP, Research & Development

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 14,509.2451

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: 0001127602-20-005770 · form4.xml · nonDerivative · entry 4

Sandrock Alfred · CIK 0001577061 · EVP, Research & Development

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 12,926.2451

SEC source: 0001127602-20-005770 · form4.xml · nonDerivative · entry 3

Sandrock Alfred · CIK 0001577061 · EVP, Research & Development

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 13,464.2451

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: 0001127602-20-005770 · form4.xml · nonDerivative · entry 2

Sandrock Alfred · CIK 0001577061 · EVP, Research & Development

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 12,042.2451

SEC source: 0001127602-20-005770 · form4.xml · nonDerivative · entry 1

Sandrock Alfred · CIK 0001577061 · EVP, Research & Development

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 12,702.2451

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 · balance_after: Includes 82.051 shares acquired under the Biogen Inc. employee stock purchase plan on March 29, 2019.

SEC source: 0001127602-20-005782 · form4.xml · derivative · entry 5

Kramer Robin · CIK 0001609222 · VP, Chief Accounting Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 1,510

Underlying: Common Stock · 1,510 shares

Expires 2023-02-12

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: 0001127602-20-005782 · form4.xml · derivative · entry 4

Kramer Robin · CIK 0001609222 · VP, Chief Accounting Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 574

Underlying: Common Stock · 154 shares

Expires 2022-02-12

F2 · shares: 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: 0001127602-20-005782 · form4.xml · derivative · entry 3

Kramer Robin · CIK 0001609222 · VP, Chief Accounting Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 728

Underlying: Common Stock · 132 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: 0001127602-20-005782 · form4.xml · nonDerivative · entry 2

Kramer Robin · CIK 0001609222 · VP, Chief Accounting Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 236.481

SEC source: 0001127602-20-005782 · form4.xml · nonDerivative · entry 1

Kramer Robin · CIK 0001609222 · VP, Chief Accounting Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 282.481

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: 0001127602-20-005781 · form4.xml · derivative · entry 5

Karp Daniel · CIK 0001744046 · EVP, Corporate Development

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 6,030

Underlying: Common Stock · 6,030 shares

Expires 2023-02-12

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: 0001127602-20-005781 · form4.xml · derivative · entry 4

Karp Daniel · CIK 0001744046 · EVP, Corporate Development

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 4,174

Underlying: Common Stock · 1,126 shares

Expires 2022-02-12

F2 · shares: This represents the difference between the maximum possible number of shares that were eligible for vesting and the actual number of shares 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: 0001127602-20-005781 · form4.xml · derivative · entry 3

Karp Daniel · CIK 0001744046 · EVP, Corporate Development

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 5,300

Underlying: Common Stock · 960 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: 0001127602-20-005781 · form4.xml · nonDerivative · entry 2

Karp Daniel · CIK 0001744046 · EVP, Corporate Development

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 930.387

SEC source: 0001127602-20-005781 · form4.xml · nonDerivative · entry 1

Karp Daniel · CIK 0001744046 · EVP, Corporate Development

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 1,224.387

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: 0001127602-20-005780 · 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: 11,450

Underlying: Common Stock · 11,450 shares

Expires 2023-02-12

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: 0001127602-20-005780 · form4.xml · derivative · entry 4

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

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 7,308

Underlying: Common Stock · 1,972 shares

Expires 2022-02-12

F2 · shares: 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: 0001127602-20-005780 · form4.xml · derivative · entry 3

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

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 9,280

Underlying: Common Stock · 1,680 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: 0001127602-20-005780 · 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: 3,871

SEC source: 0001127602-20-005780 · 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: 4,375

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: 0001127602-20-005779 · form4.xml · derivative · entry 12

Gregory Ginger · CIK 0001545716 · EVP, Human Resources

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 7,540

Underlying: Common Stock · 7,540 shares

Expires 2023-02-12

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: 0001127602-20-005779 · form4.xml · derivative · entry 11

Gregory Ginger · CIK 0001545716 · EVP, Human Resources

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 4,594

Underlying: Common Stock · 1,240 shares

Expires 2022-02-12

F3 · shares: 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: 0001127602-20-005779 · form4.xml · derivative · entry 10

Gregory Ginger · CIK 0001545716 · EVP, Human Resources

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 5,834

Underlying: Common Stock · 1,056 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: 0001127602-20-005779 · form4.xml · derivative · entry 9

Gregory Ginger · CIK 0001545716 · EVP, Human Resources

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 1,896

Underlying: Common Stock · 918 shares

Expires 2021-02-12

F3 · shares: 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: 0001127602-20-005779 · form4.xml · derivative · entry 8

Gregory Ginger · CIK 0001545716 · EVP, Human Resources

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 2,814

Underlying: Common Stock · 974 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: 0001127602-20-005779 · form4.xml · derivative · entry 7

Gregory Ginger · CIK 0001545716 · EVP, Human Resources

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 1,517 shares

Expires 2020-02-12

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 restricted stock units will vest in 2 annual installments. One-third will vest on the first anniversary of the grant date and two-thirds will vest on the second anniversary of the grant date.

SEC source: 0001127602-20-005779 · form4.xml · nonDerivative · entry 6

Gregory Ginger · CIK 0001545716 · EVP, Human Resources

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 4,603

SEC source: 0001127602-20-005779 · form4.xml · nonDerivative · entry 5

Gregory Ginger · CIK 0001545716 · EVP, Human Resources

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 5,021

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: 0001127602-20-005779 · form4.xml · nonDerivative · entry 4

Gregory Ginger · CIK 0001545716 · EVP, Human Resources

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 3,965

SEC source: 0001127602-20-005779 · form4.xml · nonDerivative · entry 3

Gregory Ginger · CIK 0001545716 · EVP, Human Resources

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 4,251

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: 0001127602-20-005779 · form4.xml · nonDerivative · entry 2

Gregory Ginger · CIK 0001545716 · EVP, Human Resources

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 3,277

SEC source: 0001127602-20-005779 · form4.xml · nonDerivative · entry 1

Gregory Ginger · CIK 0001545716 · EVP, Human Resources

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 3,732

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.