BIOGEN INC

Ticker: BIIB CUSIP: 09062X103 Class: COM

Avidity Partners Management LP's Holding History (CIK: 0001791827)

Note: Option positions (PUT/CALL) are excluded.

Q3 2023

Shares 115,400 Value ($000) $29,659 Avg Close $267.47 Range $251.85 - $287.60

Q2 2023

Shares 174,000 Value ($000) $49,564 Avg Close $297.86 Range $273.39 - $319.76

Q1 2023

Shares 128,800 Value ($000) $35,810 Avg Close $276.70 Range $254.80 - $295.90

Q3 2022

Shares 600,000 Value ($000) $160,200 Avg Close $212.38 Range $193.65 - $283.44

Q2 2022

Shares 440,566 Value ($000) $89,849 Avg Close $204.43 Range $187.16 - $225.50

Q1 2022

Shares 365,000 Value ($000) $76,869 Avg Close $217.46 Range $192.67 - $249.00

Q2 2021

Shares 183,900 Value ($000) $63,679 Avg Close $302.94 Range $257.03 - $468.55

Q3 2020

Shares 315,100 Value ($000) $89,388 Avg Close $278.91 Range $261.87 - $312.00

Q1 2020

Shares 62,000 Value ($000) $19,616 Avg Close $303.47 Range $262.25 - $374.99

Period	Shares	Value ($000)	Average Close	Price Range
Q3 2023	115,400	$29,659	$267.47	$251.85 - $287.60
Q2 2023	174,000	$49,564	$297.86	$273.39 - $319.76
Q1 2023	128,800	$35,810	$276.70	$254.80 - $295.90
Q3 2022	600,000	$160,200	$212.38	$193.65 - $283.44
Q2 2022	440,566	$89,849	$204.43	$187.16 - $225.50
Q1 2022	365,000	$76,869	$217.46	$192.67 - $249.00
Q2 2021	183,900	$63,679	$302.94	$257.03 - $468.55
Q3 2020	315,100	$89,388	$278.91	$261.87 - $312.00
Q1 2020	62,000	$19,616	$303.47	$262.25 - $374.99