BIOGEN INC

Ticker: BIIB CUSIP: 09062X103 Class: COM

Arizona State Retirement System's Holding History (CIK: 0001558481)

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

Q4 2025

Shares 40,220 Value ($000) $7,078 Avg Close $163.37 Range $138.00 - $185.17

Q3 2025

Shares 43,419 Value ($000) $6,082 Avg Close $135.17 Range $121.05 - $150.28

Q2 2025

Shares 42,753 Value ($000) $5,369 Avg Close $124.60 Range $110.04 - $137.32

Q1 2025

Shares 42,114 Value ($000) $5,763 Avg Close $142.96 Range $128.51 - $157.09

Q4 2024

Shares 40,770 Value ($000) $6,235 Avg Close $168.67 Range $145.07 - $195.00

Q3 2024

Shares 41,721 Value ($000) $8,087 Avg Close $209.21 Range $188.78 - $238.00

Q2 2024

Shares 42,140 Value ($000) $9,769 Avg Close $217.32 Range $189.44 - $237.54

Q1 2024

Shares 41,581 Value ($000) $8,966 Avg Close $234.20 Range $211.02 - $268.30

Q4 2023

Shares 40,745 Value ($000) $10,544 Avg Close $245.62 Range $220.86 - $269.43

Q3 2023

Shares 40,970 Value ($000) $10,530 Avg Close $267.47 Range $251.85 - $287.60

Q2 2023

Shares 41,301 Value ($000) $11,765 Avg Close $297.86 Range $273.39 - $319.76

Q1 2023

Shares 39,319 Value ($000) $10,932 Avg Close $276.70 Range $254.80 - $295.90

Q4 2022

Shares 39,540 Value ($000) $10,949 Avg Close $282.44 Range $250.31 - $311.88

Q3 2022

Shares 39,809 Value ($000) $10,629 Avg Close $212.38 Range $193.65 - $283.44

Q2 2022

Shares 40,319 Value ($000) $8,223 Avg Close $204.43 Range $187.16 - $225.50

Q1 2022

Shares 40,307 Value ($000) $8,489 Avg Close $217.46 Range $192.67 - $249.00

Q4 2021

Shares 40,818 Value ($000) $9,793 Avg Close $257.12 Range $221.72 - $290.76

Q3 2021

Shares 41,984 Value ($000) $11,881 Avg Close $327.75 Range $282.64 - $372.12

Q2 2021

Shares 42,681 Value ($000) $14,779 Avg Close $302.94 Range $257.03 - $468.55

Q1 2021

Shares 43,364 Value ($000) $12,131 Avg Close $269.69 Range $238.40 - $296.38

Q4 2020

Shares 45,678 Value ($000) $11,185 Avg Close $259.08 Range $223.25 - $363.92

Q3 2020

Shares 49,629 Value ($000) $14,079 Avg Close $278.91 Range $261.87 - $312.00

Q2 2020

Shares 40,888 Value ($000) $10,940 Avg Close $300.59 Range $257.60 - $350.24

Q1 2020

Shares 32,444 Value ($000) $10,265 Avg Close $303.47 Range $262.25 - $374.99

Q4 2019

Shares 33,882 Value ($000) $10,054 Avg Close $277.46 Range $219.70 - $318.00

Q3 2019

Shares 34,442 Value ($000) $8,019 Avg Close $232.85 Range $215.78 - $246.99

Q2 2019

Shares 36,877 Value ($000) $8,624 Avg Close $230.90 Range $219.20 - $245.35

Q1 2019

Shares 37,772 Value ($000) $8,929 Avg Close $314.89 Range $216.12 - $344.00

Q4 2018

Shares 41,398 Value ($000) $12,457 Avg Close $319.14 Range $278.46 - $358.41

Q3 2018

Shares 49,929 Value ($000) $17,640 Avg Close $344.30 Range $288.13 - $388.67

Q2 2018

Shares 51,857 Value ($000) $15,051 Avg Close $281.15 Range $249.17 - $310.91

Q1 2018

Shares 52,469 Value ($000) $14,367 Avg Close $310.41 Range $259.76 - $370.57

Q4 2017

Shares 53,569 Value ($000) $17,065 Avg Close $320.80 Range $301.81 - $348.84

Q3 2017

Shares 52,398 Value ($000) $16,407 Avg Close $296.11 Range $269.50 - $330.00

Q2 2017

Shares 52,998 Value ($000) $14,382 Avg Close $264.42 Range $244.28 - $291.90

Q1 2017

Shares 53,498 Value ($000) $14,627 Avg Close $282.75 Range $260.50 - $301.42

Q4 2016

Shares 53,798 Value ($000) $15,256 Avg Close $296.43 Range $268.00 - $329.83

Q3 2016

Shares 53,998 Value ($000) $16,903 Avg Close $296.18 Range $240.07 - $333.65

Q2 2016

Shares 53,698 Value ($000) $12,985 Avg Close $263.54 Range $223.02 - $292.69

Q1 2016

Shares 59,298 Value ($000) $15,436 Avg Close $264.15 Range $242.07 - $301.02

Q4 2015

Shares 59,398 Value ($000) $18,197 Avg Close $287.35 Range $254.00 - $311.65

Q3 2015

Shares 64,298 Value ($000) $18,763 Avg Close $330.23 Range $265.00 - $412.24

Q4 2014

Shares 66,098 Value ($000) $22,436 Avg Close $323.51 Range $290.85 - $361.93

Q3 2014

Shares 65,698 Value ($000) $21,733 Avg Close $329.72 Range $298.31 - $349.00

Q2 2014

Shares 67,698 Value ($000) $21,345 Avg Close $300.97 Range $272.02 - $322.25

Q1 2014

Shares 64,798 Value ($000) $19,819 Avg Close $317.43 Range $270.62 - $358.89

Q4 2013

Shares 67,498 Value ($000) $18,882 Avg Close $258.65 Range $221.07 - $298.82

Q3 2013

Shares 69,798 Value ($000) $16,804 Avg Close $223.81 Range $203.55 - $248.95

Q2 2013

Shares 71,098 Value ($000) $15,300 Avg Close $213.68 Range $191.80 - $242.64

Q1 2013

Shares 73,251 Value ($000) $14,130 Avg Close $161.63 Range $139.72 - $192.92

Period	Shares	Value ($000)	Average Close	Price Range
Q4 2025	40,220	$7,078	$163.37	$138.00 - $185.17
Q3 2025	43,419	$6,082	$135.17	$121.05 - $150.28
Q2 2025	42,753	$5,369	$124.60	$110.04 - $137.32
Q1 2025	42,114	$5,763	$142.96	$128.51 - $157.09
Q4 2024	40,770	$6,235	$168.67	$145.07 - $195.00
Q3 2024	41,721	$8,087	$209.21	$188.78 - $238.00
Q2 2024	42,140	$9,769	$217.32	$189.44 - $237.54
Q1 2024	41,581	$8,966	$234.20	$211.02 - $268.30
Q4 2023	40,745	$10,544	$245.62	$220.86 - $269.43
Q3 2023	40,970	$10,530	$267.47	$251.85 - $287.60
Q2 2023	41,301	$11,765	$297.86	$273.39 - $319.76
Q1 2023	39,319	$10,932	$276.70	$254.80 - $295.90
Q4 2022	39,540	$10,949	$282.44	$250.31 - $311.88
Q3 2022	39,809	$10,629	$212.38	$193.65 - $283.44
Q2 2022	40,319	$8,223	$204.43	$187.16 - $225.50
Q1 2022	40,307	$8,489	$217.46	$192.67 - $249.00
Q4 2021	40,818	$9,793	$257.12	$221.72 - $290.76
Q3 2021	41,984	$11,881	$327.75	$282.64 - $372.12
Q2 2021	42,681	$14,779	$302.94	$257.03 - $468.55
Q1 2021	43,364	$12,131	$269.69	$238.40 - $296.38
Q4 2020	45,678	$11,185	$259.08	$223.25 - $363.92
Q3 2020	49,629	$14,079	$278.91	$261.87 - $312.00
Q2 2020	40,888	$10,940	$300.59	$257.60 - $350.24
Q1 2020	32,444	$10,265	$303.47	$262.25 - $374.99
Q4 2019	33,882	$10,054	$277.46	$219.70 - $318.00
Q3 2019	34,442	$8,019	$232.85	$215.78 - $246.99
Q2 2019	36,877	$8,624	$230.90	$219.20 - $245.35
Q1 2019	37,772	$8,929	$314.89	$216.12 - $344.00
Q4 2018	41,398	$12,457	$319.14	$278.46 - $358.41
Q3 2018	49,929	$17,640	$344.30	$288.13 - $388.67
Q2 2018	51,857	$15,051	$281.15	$249.17 - $310.91
Q1 2018	52,469	$14,367	$310.41	$259.76 - $370.57
Q4 2017	53,569	$17,065	$320.80	$301.81 - $348.84
Q3 2017	52,398	$16,407	$296.11	$269.50 - $330.00
Q2 2017	52,998	$14,382	$264.42	$244.28 - $291.90
Q1 2017	53,498	$14,627	$282.75	$260.50 - $301.42
Q4 2016	53,798	$15,256	$296.43	$268.00 - $329.83
Q3 2016	53,998	$16,903	$296.18	$240.07 - $333.65
Q2 2016	53,698	$12,985	$263.54	$223.02 - $292.69
Q1 2016	59,298	$15,436	$264.15	$242.07 - $301.02
Q4 2015	59,398	$18,197	$287.35	$254.00 - $311.65
Q3 2015	64,298	$18,763	$330.23	$265.00 - $412.24
Q4 2014	66,098	$22,436	$323.51	$290.85 - $361.93
Q3 2014	65,698	$21,733	$329.72	$298.31 - $349.00
Q2 2014	67,698	$21,345	$300.97	$272.02 - $322.25
Q1 2014	64,798	$19,819	$317.43	$270.62 - $358.89
Q4 2013	67,498	$18,882	$258.65	$221.07 - $298.82
Q3 2013	69,798	$16,804	$223.81	$203.55 - $248.95
Q2 2013	71,098	$15,300	$213.68	$191.80 - $242.64
Q1 2013	73,251	$14,130	$161.63	$139.72 - $192.92