Sandrock Alfred

SEC source: 0001104659-26-039691 · tm2611148-1_4seq1.xml · nonDerivative · entry 1

Sandrock Alfred · CIK 0001577061 · Director · President and CEO

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 472,549

F1 · kind: Represents shares of common stock of Voyager Therapeutics, Inc. (the "Corporation") sold, pursuant to a durable automatic sale instruction adopted by the reporting person on May 12, 2025, effecting the sell-to-cover election of the reporting person to satisfy tax withholding obligations, in connection with the vesting of restricted stock units on April 1, 2026. The sales do not represent a discretionary trade by the reporting person.

F1 · shares: Represents shares of common stock of Voyager Therapeutics, Inc. (the "Corporation") sold, pursuant to a durable automatic sale instruction adopted by the reporting person on May 12, 2025, effecting the sell-to-cover election of the reporting person to satisfy tax withholding obligations, in connection with the vesting of restricted stock units on April 1, 2026. The sales do not represent a discretionary trade by the reporting person.

F2 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $3.81 to $3.95, inclusive. The reporting person undertakes to provide to the Corporation, any security holder of the Corporation, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in footnote (2) to this Form 4.

SEC source: 0001104659-26-020181 · tm267337-3_4seq1.xml · nonDerivative · entry 1

Sandrock Alfred · CIK 0001577061 · Director · President and CEO

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 484,060

F1 · kind: Represents shares of common stock of Voyager Therapeutics, Inc. (the "Corporation") sold, pursuant to a durable automatic sale instruction adopted by the reporting person on May 12, 2025, effecting the sell-to-cover election of the reporting person to satisfy tax withholding obligations, in connection with the vesting of restricted stock units on February 21, 2026. The sales do not represent a discretionary trade by the reporting person.

F1 · shares: Represents shares of common stock of Voyager Therapeutics, Inc. (the "Corporation") sold, pursuant to a durable automatic sale instruction adopted by the reporting person on May 12, 2025, effecting the sell-to-cover election of the reporting person to satisfy tax withholding obligations, in connection with the vesting of restricted stock units on February 21, 2026. The sales do not represent a discretionary trade by the reporting person.

F2 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $3.61 to $3.86, inclusive. The reporting person undertakes to provide to the Corporation, any security holder of the Corporation, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in footnote (2) to this Form 4.

SEC source: 0001104659-26-018126 · tm266896-1_4seq1.xml · nonDerivative · entry 1

Sandrock Alfred · CIK 0001577061 · Director · President and CEO

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 498,257

F1 · kind: Represents shares of common stock of Voyager Therapeutics, Inc. (the "Corporation") sold, pursuant to a durable automatic sale instruction adopted by the reporting person on May 12, 2025, effecting the sell-to-cover election of the reporting person to satisfy tax withholding obligations, in connection with the vesting of restricted stock units on February 17, 2026. The sales do not represent a discretionary trade by the reporting person.

F1 · shares: Represents shares of common stock of Voyager Therapeutics, Inc. (the "Corporation") sold, pursuant to a durable automatic sale instruction adopted by the reporting person on May 12, 2025, effecting the sell-to-cover election of the reporting person to satisfy tax withholding obligations, in connection with the vesting of restricted stock units on February 17, 2026. The sales do not represent a discretionary trade by the reporting person.

F2 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $3.35 to $3.47, inclusive. The reporting person undertakes to provide to the Corporation, any security holder of the Corporation, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in footnote (2) to this Form 4.

SEC source: 0001104659-26-013414 · tm266069-2_4seq1.xml · nonDerivative · entry 1

Sandrock Alfred · CIK 0001577061 · Director · President and CEO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 509,989

F1 · kind: Represents shares of common stock sold, pursuant to a durable automatic sales instruction letter effecting the sell-to-cover election of the reporting person to satisfy tax withholding obligations, in connection with the vesting of restricted stock units on February 9, 2026. The sales do not represent a discretionary trade by the reporting person.

F1 · shares: Represents shares of common stock sold, pursuant to a durable automatic sales instruction letter effecting the sell-to-cover election of the reporting person to satisfy tax withholding obligations, in connection with the vesting of restricted stock units on February 9, 2026. The sales do not represent a discretionary trade by the reporting person.

F2 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $3.68 to $3.91, inclusive. The reporting person undertakes to provide to Voyager Therapeutics, Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in footnote (2) to this Form 4.

SEC source: 0001104659-26-012672 · tm265871-2_4seq1.xml · derivative · entry 2

Sandrock Alfred · CIK 0001577061 · Director · President and CEO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 402,500

Underlying: Common Stock · 402,500 shares

Expires 2036-02-06

F3 · derivative.exercise_date: This stock option was issued pursuant to the Plan. The vesting commencement date of the option is the grant date, February 6, 2026. The option vests over four years, with 1/48th of the shares of common stock underlying the option vesting upon the one-month anniversary of such vesting commencement date and an additional 1/48th of the shares of common stock underlying the option vesting at the end of each successive one-month period thereafter, subject to the Reporting Person's continued service.

SEC source: 0001104659-26-012672 · tm265871-2_4seq1.xml · nonDerivative · entry 1

Sandrock Alfred · CIK 0001577061 · Director · President and CEO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 522,181

F1 · shares: Consists of shares of common stock issuable under an aggregate of 86,250 restricted stock units ("RSUs") awarded to the Reporting Person pursuant to the Voyager Therapeutics, Inc. 2025 Stock Incentive Plan (the "Plan"). Each RSU represents the right to receive one share of common stock upon vesting. The vesting commencement date of the RSU award is the grant date, February 6, 2026. The RSU award vests over three years, with 1/3rd of the shares of common stock underlying the RSU award vesting on the one-year anniversary of such vesting commencement date and an additional 1/3rd of the shares of common stock underlying the RSU award vesting at the end of each successive one-year period thereafter, subject to the Reporting Person's continued service.

F2 · balance_after: Includes 5,000 shares of common stock acquired under the Voyager Therapeutics, Inc. Amended and Restated 2015 Employee Stock Purchase Plan since the date of the reporting person's last Form 4.

SEC source: 0001104659-25-032202 · tm2511532-1_4seq1.xml · nonDerivative · entry 1

Sandrock Alfred · CIK 0001577061 · Director · President and CEO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 430,931

F1 · shares: Represents shares of common stock sold, pursuant to a durable automatic sales instruction letter effecting the sell-to-cover election of the reporting person to satisfy tax withholding obligations, in connection with the vesting of restricted stock units on April 1, 2025. The sales do not represent a discretionary trade by the reporting person.

F2 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $3.34 to $3.52, inclusive. The reporting person undertakes to provide to Voyager Therapeutics, Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in footnote (2) to this Form 4.

SEC source: 0001104659-25-016520 · tm257355-5_4seq1.xml · derivative · entry 3

Sandrock Alfred · CIK 0001577061 · Director · President and CEO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 290,000

Underlying: Common Stock · 290,000 shares

Expires 2035-02-21

F4 · derivative.exercise_date: This stock option was issued pursuant to the Plan. The vesting commencement date of the option is the grant date, February 21, 2025. The option vests over four years, with 1/48th of the shares of common stock underlying the option vesting upon the one-month anniversary of such vesting commencement date and an additional 1/48th of the shares of common stock underlying the option vesting at the end of each successive one-month period thereafter, subject to the Reporting Person's continued service.

SEC source: 0001104659-25-016520 · tm257355-5_4seq1.xml · nonDerivative · entry 2

Sandrock Alfred · CIK 0001577061 · Director · President and CEO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 441,816

F3 · shares: Consists of shares of common stock issuable under an aggregate of 145,000 restricted stock units ("RSUs") awarded to the Reporting Person pursuant to the Voyager Therapeutics, Inc. 2015 Stock Option and Incentive Plan (the "Plan"). Each RSU represents the right to receive one share of common stock upon vesting. The vesting commencement date of the RSU award is the grant date, February 21, 2025. The RSU award vests over three years, with 1/3rd of the shares of common stock underlying the RSU award vesting on the one-year anniversary of such vesting commencement date and an additional 1/3rd of the shares of common stock underlying the RSU award vesting at the end of each successive one-year period thereafter, subject to the Reporting Person's continued service.

SEC source: 0001104659-25-016520 · tm257355-5_4seq1.xml · nonDerivative · entry 1

Sandrock Alfred · CIK 0001577061 · Director · President and CEO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 296,816

F1 · shares: Represents shares of common stock sold, pursuant to a durable automatic sales instruction letter effecting the sell-to-cover election of the reporting person to satisfy tax withholding obligations, in connection with the vesting of restricted stock units on February 17, 2025. The sales do not represent a discretionary trade by the reporting person.

F2 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $4.21 to $4.32, inclusive. The reporting person undertakes to provide to Voyager Therapeutics, Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in footnote (2) to this Form 4.

SEC source: 0001104659-25-012196 · tm256369-2_4seq1.xml · nonDerivative · entry 1

Sandrock Alfred · CIK 0001577061 · President & CEO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 308,518

F1 · shares: Represents shares of common stock sold, pursuant to a durable automatic sales instruction letter effecting the sell-to-cover election of the reporting person to satisfy tax withholding obligations, in connection with the vesting of restricted stock units on February 9, 2025. The sales do not represent a discretionary trade by the reporting person.

F2 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $4.13 to $5.00, inclusive. The reporting person undertakes to provide to Voyager Therapeutics, Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in footnote (2) to this Form 4.

F3 · balance_after: Includes 2,323 shares of common stock acquired under the Voyager Therapeutics, Inc. 2015 Employee Stock Purchase Plan since the date of the reporting person's last Form 4.

SEC source: 0001104659-24-043104 · tm2410775-1_4seq1.xml · nonDerivative · entry 1

Sandrock Alfred · CIK 0001577061 · Director · President and CEO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 322,839

F1 · kind: Represents shares of common stock sold, pursuant to a durable automatic sales instruction letter effecting the sell-to-cover election of the reporting person to satisfy tax withholding obligations, in connection with the vesting of restricted stock units on April 1, 2024. The sales do not represent a discretionary trade by the reporting person.

F1 · shares: Represents shares of common stock sold, pursuant to a durable automatic sales instruction letter effecting the sell-to-cover election of the reporting person to satisfy tax withholding obligations, in connection with the vesting of restricted stock units on April 1, 2024. The sales do not represent a discretionary trade by the reporting person.

F2 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $9.71 to $10.02, inclusive. The reporting person undertakes to provide to Voyager Therapeutics, Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in footnote (2) to this Form 4.

SEC source: 0001104659-24-026561 · tm246990-3_4seq1.xml · nonDerivative · entry 1

Sandrock Alfred · CIK 0001577061 · Director · President and CEO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 334,954

F1 · kind: Represents shares of common stock sold, pursuant to a durable automatic sales instruction letter effecting the sell-to-cover election of the reporting person to satisfy tax withholding obligations, in connection with the vesting of restricted stock units on February 17, 2024. The sales do not represent a discretionary trade by the reporting person.

F1 · shares: Represents shares of common stock sold, pursuant to a durable automatic sales instruction letter effecting the sell-to-cover election of the reporting person to satisfy tax withholding obligations, in connection with the vesting of restricted stock units on February 17, 2024. The sales do not represent a discretionary trade by the reporting person.

F2 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $7.35 to $7.55, inclusive. The reporting person undertakes to provide to Voyager Therapeutics, Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in footnote (2) to this Form 4.

SEC source: 0001104659-24-024982 · tm246517-2_4seq1.xml · derivative · entry 2

Sandrock Alfred · CIK 0001577061 · Director · President and CEO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 260,000

Underlying: Common Stock · 260,000 shares

Expires 2034-02-09

F3 · derivative.exercise_date: This stock option was issued pursuant to the Plan. The vesting commencement date of the option is the grant date, February 9, 2024. The option vests over four years, with 1/48th of the shares of common stock underlying the option vesting upon the one-month anniversary of such vesting commencement date and an additional 1/48th of the shares of common stock underlying the option vesting at the end of each successive one-month period thereafter, subject to the Reporting Person's continued service.

SEC source: 0001104659-24-024982 · tm246517-2_4seq1.xml · nonDerivative · entry 1

Sandrock Alfred · CIK 0001577061 · Director · President and CEO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 347,987

F1 · shares: Consists of shares of common stock issuable under an aggregate of 130,000 restricted stock units ("RSUs") awarded to the Reporting Person pursuant to the Voyager Therapeutics, Inc. 2015 Stock Option and Incentive Plan (the "Plan"). Each RSU represents the right to receive one share of common stock upon vesting. The vesting commencement date of the RSU award is the grant date, February 9, 2024. The RSU award vests over three years, with 1/3rd of the shares of common stock underlying the RSU award vesting on the one-year anniversary of such vesting commencement date and an additional 1/3rd of the shares of common stock underlying the RSU award vesting at the end of each successive one-year period thereafter, subject to the Reporting Person's continued service.

F2 · balance_after: Includes 3,369 shares of common stock acquired under the Voyager Therapeutics, Inc. 2015 Employee Stock Purchase Plan since the date of the reporting person's last Form 4.

SEC source: 0001104659-23-042230 · tm2311887-1_4seq1.xml · nonDerivative · entry 1

Sandrock Alfred · CIK 0001577061 · Director · President and CEO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 214,618

F1 · kind: Represents shares of common stock sold, pursuant to a durable automatic sales instruction letter effecting the sell-to-cover election of the Reporting Person to satisfy tax withholding obligations, in connection with the vesting of restricted stock units on April 1, 2023. The sales do not represent a discretionary trade by the Reporting Person.

F1 · shares: Represents shares of common stock sold, pursuant to a durable automatic sales instruction letter effecting the sell-to-cover election of the Reporting Person to satisfy tax withholding obligations, in connection with the vesting of restricted stock units on April 1, 2023. The sales do not represent a discretionary trade by the Reporting Person.

F2 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $7.54 to $8.18, inclusive. The Reporting Person undertakes to provide to Voyager Therapeutics, Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in footnote (2) to this Form 4.

SEC source: 0001104659-23-024418 · tm237526-1_4seq1.xml · derivative · entry 2

Sandrock Alfred · CIK 0001577061 · Director · President and CEO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 240,000

Underlying: Common Stock · 240,000 shares

Expires 2033-02-17

F3 · derivative.exercise_date: This stock option was issued pursuant to the Plan. The vesting commencement date of the option is the grant date, February 17, 2023. The option vests over four years, with 1/48th of the shares of common stock underlying the option vesting upon the one-month anniversary of such vesting commencement date and an additional 1/48th of the shares of common stock underlying the option vesting at the end of each successive one-month period thereafter, subject to the Reporting Person's continued service.

SEC source: 0001104659-23-024418 · tm237526-1_4seq1.xml · nonDerivative · entry 1

Sandrock Alfred · CIK 0001577061 · Director · President and CEO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 222,055

F1 · shares: Consists of shares of common stock issuable under an aggregate of 120,000 restricted stock units ("RSUs") awarded to the Reporting Person pursuant to the Voyager Therapeutics, Inc. 2015 Stock Option and Incentive Plan (the "Plan"). Each RSU represents the right to receive one share of common stock upon vesting. The vesting commencement date of the RSU award is the grant date, February 17, 2023. The RSU award vests over three years, with 1/3rd of the shares of common stock underlying the RSU award vesting on the one-year anniversary of such vesting commencement date and an additional 1/3rd of the shares of common stock underlying the RSU award vesting at the end of each successive one-year period thereafter, subject to the Reporting Person's continued service.

F2 · balance_after: Includes 2,055 shares of common stock acquired under the Voyager Therapeutics, Inc. 2015 Employee Stock Purchase Plan on December 31, 2022.

SEC source: 0001104659-22-037149 · tm2210284-1_4seq1.xml · derivative · entry 2

Sandrock Alfred · CIK 0001577061 · Director · President and CEO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 940,600

Underlying: Common Stock · 940,600 shares

Expires 2032-03-22

F2 · derivative.exercise_date: This stock option was issued pursuant to the Plan. The vesting commencement date of the option is the grant date, March 22, 2022. The option vests over four years, with 1/4th of the shares of common stock underlying the option vesting upon the one-year anniversary of such vesting commencement date and an additional 1/48th of the shares of common stock underlying the option vesting at the end of each successive one-month period thereafter, subject to the Reporting Person's continued service as an employee.

SEC source: 0001104659-22-037149 · tm2210284-1_4seq1.xml · nonDerivative · entry 1

Sandrock Alfred · CIK 0001577061 · Director · President and CEO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 100,000

F1 · shares: Consists of shares of common stock issuable under an aggregate of 100,000 restricted stock units ("RSUs") awarded to the Reporting Person pursuant to the Voyager Therapeutics, Inc. 2015 Stock Option and Incentive Plan (the "Plan"). Each RSU represents the right to receive one share of common stock upon vesting. The vesting commencement date of the RSU award is April 1, 2022. The RSU award vests over four years, with 1/4th of the shares of common stock underlying the RSU award vesting on the one-year anniversary of such vesting commencement date and an additional 1/4th of the shares of common stock underlying the RSU award vesting at the end of each successive one-year period thereafter, subject to the Reporting Person's continued service as an employee.

SEC source: 0001104659-22-017123 · tm225933-3_4seq1.xml · derivative · entry 1

Sandrock Alfred · CIK 0001577061 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 44,000

Underlying: Common Stock · 44,000 shares

Expires 2032-02-07

F1 · derivative.exercise_date: This stock option was issued pursuant to the Voyager Therapeutics, Inc. 2015 Stock Option and Incentive Plan. The vesting commencement date of the option is the grant date, February 7, 2022. The option vests over four years, with 1/16th of the shares of common stock underlying the option vesting upon the three-month anniversary of such vesting commencement date and an additional 1/16th of the shares of common stock underlying the option vesting at the end of each successive three-month period thereafter, subject to the Reporting Person's continued service.

SEC source: 0001127602-21-019553 · form4.xml · nonDerivative · entry 1

Sandrock Alfred · CIK 0001577061 · Head of Research & Development

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 10,169.1121

F1 · kind: Sale pursuant to a trading plan intended to comply with Rule 10b5-1 of the Securities Exchange Act of 1934.

F2 · balance_after: Includes 102.902 shares acquired under the Biogen Inc. employee stock purchase plan on 3/31/2021.

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: 0001127602-21-006278 · 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: 0001127602-21-002974 · form4.xml · nonDerivative · entry 1

Sandrock Alfred · CIK 0001577061 · EVP, Research & Development

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 16,794.2101

F1 · shares: Represents shares earned upon satisfaction of certain performance conditions associated with performance stock units granted on February 12, 2018. The shares will vest on February 12, 2021.

SEC source: 0001127602-20-028410 · form4.xml · nonDerivative · entry 1

Sandrock Alfred · CIK 0001577061 · EVP, Research & Development

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 13,066.2101

F1 · kind: Sale pursuant to a trading plan intended to comply with Rule 10b5-1 of the Securities Exchange Act of 1934.

F2 · balance_after: Includes 84.965 shares acquired under the Biogen Inc. employee stock purchase plan on March 31, 2020.

SEC source: 0001127602-20-006549 · form4.xml · derivative · entry 4

Sandrock Alfred · CIK 0001577061 · EVP, Research & Development

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 915 shares

Expires 2020-02-15

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 on the grant date]).

SEC source: 0001127602-20-006549 · form4.xml · derivative · entry 3

Sandrock Alfred · CIK 0001577061 · EVP, Research & Development

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 915

Underlying: Common Stock · 1,213 shares

Expires 2020-02-15

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 on the grant date]).

SEC source: 0001127602-20-006549 · form4.xml · nonDerivative · entry 2

Sandrock Alfred · CIK 0001577061 · EVP, Research & Development

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 14,481.2451

SEC source: 0001127602-20-006549 · form4.xml · nonDerivative · entry 1

Sandrock Alfred · CIK 0001577061 · EVP, Research & Development

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 15,019.2451

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 · 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.