BIOGEN INC

Ticker: BIIB CUSIP: 09062X103 Class: COM

TEACHERS RETIREMENT SYSTEM OF THE STATE OF KENTUCKY's Holding History (CIK: 0000714142)

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

Q4 2025

Shares 11,437 Value ($000) $2 Avg Close $163.37 Range $138.00 - $185.17

Q3 2025

Shares 11,437 Value ($000) $2 Avg Close $135.17 Range $121.05 - $150.28

Q2 2025

Shares 11,437 Value ($000) $1 Avg Close $124.60 Range $110.04 - $137.32

Q1 2025

Shares 11,213 Value ($000) $2 Avg Close $142.96 Range $128.51 - $157.09

Q4 2024

Shares 10,912 Value ($000) $2 Avg Close $168.67 Range $145.07 - $195.00

Q3 2024

Shares 10,912 Value ($000) $2 Avg Close $209.21 Range $188.78 - $238.00

Q2 2024

Shares 11,532 Value ($000) $3 Avg Close $217.32 Range $189.44 - $237.54

Q1 2024

Shares 11,849 Value ($000) $3 Avg Close $234.20 Range $211.02 - $268.30

Q4 2023

Shares 12,487 Value ($000) $3 Avg Close $245.62 Range $220.86 - $269.43

Q3 2023

Shares 13,008 Value ($000) $3 Avg Close $267.47 Range $251.85 - $287.60

Q2 2023

Shares 13,008 Value ($000) $4 Avg Close $297.86 Range $273.39 - $319.76

Q1 2023

Shares 13,536 Value ($000) $4 Avg Close $276.70 Range $254.80 - $295.90

Q4 2022

Shares 13,536 Value ($000) $4 Avg Close $282.44 Range $250.31 - $311.88

Q3 2022

Shares 13,536 Value ($000) $3,614 Avg Close $212.38 Range $193.65 - $283.44

Q1 2022

Shares 10,525 Value ($000) $2,217 Avg Close $217.46 Range $192.67 - $249.00

Q4 2021

Shares 10,983 Value ($000) $2,635 Avg Close $257.12 Range $221.72 - $290.76

Q3 2021

Shares 11,740 Value ($000) $3,322 Avg Close $327.75 Range $282.64 - $372.12

Q2 2021

Shares 11,740 Value ($000) $4,065 Avg Close $302.94 Range $257.03 - $468.55

Q1 2021

Shares 81,230 Value ($000) $22,724 Avg Close $269.69 Range $238.40 - $296.38

Q4 2020

Shares 12,990 Value ($000) $3,181 Avg Close $259.08 Range $223.25 - $363.92

Q3 2020

Shares 14,490 Value ($000) $4,111 Avg Close $278.91 Range $261.87 - $312.00

Q2 2020

Shares 17,090 Value ($000) $4,572 Avg Close $300.59 Range $257.60 - $350.24

Q1 2020

Shares 52,860 Value ($000) $16,724 Avg Close $303.47 Range $262.25 - $374.99

Q4 2019

Shares 123,740 Value ($000) $36,717 Avg Close $277.46 Range $219.70 - $318.00

Q3 2019

Shares 57,110 Value ($000) $13,296 Avg Close $232.85 Range $215.78 - $246.99

Q2 2019

Shares 56,510 Value ($000) $13,216 Avg Close $230.90 Range $219.20 - $245.35

Q1 2019

Shares 89,260 Value ($000) $21,099 Avg Close $314.89 Range $216.12 - $344.00

Q4 2018

Shares 106,279 Value ($000) $31,981 Avg Close $319.14 Range $278.46 - $358.41

Q3 2018

Shares 103,409 Value ($000) $36,535 Avg Close $344.30 Range $288.13 - $388.67

Q2 2018

Shares 87,609 Value ($000) $25,427 Avg Close $281.15 Range $249.17 - $310.91

Q1 2018

Shares 87,609 Value ($000) $23,989 Avg Close $310.41 Range $259.76 - $370.57

Q4 2017

Shares 55,759 Value ($000) $17,763 Avg Close $320.80 Range $301.81 - $348.84

Q3 2017

Shares 59,340 Value ($000) $18,580 Avg Close $296.11 Range $269.50 - $330.00

Q2 2017

Shares 24,040 Value ($000) $6,523 Avg Close $264.42 Range $244.28 - $291.90

Q1 2017

Shares 57,777 Value ($000) $15,798 Avg Close $282.75 Range $260.50 - $301.42

Q4 2016

Shares 60,177 Value ($000) $17,065 Avg Close $296.43 Range $268.00 - $329.83

Q3 2016

Shares 74,861 Value ($000) $23,433 Avg Close $296.18 Range $240.07 - $333.65

Q2 2016

Shares 37,314 Value ($000) $9,023 Avg Close $263.54 Range $223.02 - $292.69

Q1 2016

Shares 38,914 Value ($000) $10,130 Avg Close $264.15 Range $242.07 - $301.02

Q4 2015

Shares 40,834 Value ($000) $12,509 Avg Close $287.35 Range $254.00 - $311.65

Q3 2015

Shares 42,294 Value ($000) $12,342 Avg Close $330.23 Range $265.00 - $412.24

Q2 2015

Shares 46,534 Value ($000) $18,797 Avg Close $401.33 Range $368.88 - $432.88

Q1 2015

Shares 49,034 Value ($000) $20,704 Avg Close $394.14 Range $334.40 - $480.18

Q4 2014

Shares 35,940 Value ($000) $12,200 Avg Close $323.51 Range $290.85 - $361.93

Q3 2014

Shares 35,740 Value ($000) $11,823 Avg Close $329.72 Range $298.31 - $349.00

Q2 2014

Shares 57,848 Value ($000) $18,240 Avg Close $300.97 Range $272.02 - $322.25

Q1 2014

Shares 60,448 Value ($000) $18,489 Avg Close $317.43 Range $270.62 - $358.89

Q4 2013

Shares 61,348 Value ($000) $17,151 Avg Close $258.65 Range $221.07 - $298.82

Q3 2013

Shares 64,878 Value ($000) $15,620 Avg Close $223.81 Range $203.55 - $248.95

Q2 2013

Shares 67,678 Value ($000) $14,565 Avg Close $213.68 Range $191.80 - $242.64

Period	Shares	Value ($000)	Average Close	Price Range
Q4 2025	11,437	$2	$163.37	$138.00 - $185.17
Q3 2025	11,437	$2	$135.17	$121.05 - $150.28
Q2 2025	11,437	$1	$124.60	$110.04 - $137.32
Q1 2025	11,213	$2	$142.96	$128.51 - $157.09
Q4 2024	10,912	$2	$168.67	$145.07 - $195.00
Q3 2024	10,912	$2	$209.21	$188.78 - $238.00
Q2 2024	11,532	$3	$217.32	$189.44 - $237.54
Q1 2024	11,849	$3	$234.20	$211.02 - $268.30
Q4 2023	12,487	$3	$245.62	$220.86 - $269.43
Q3 2023	13,008	$3	$267.47	$251.85 - $287.60
Q2 2023	13,008	$4	$297.86	$273.39 - $319.76
Q1 2023	13,536	$4	$276.70	$254.80 - $295.90
Q4 2022	13,536	$4	$282.44	$250.31 - $311.88
Q3 2022	13,536	$3,614	$212.38	$193.65 - $283.44
Q1 2022	10,525	$2,217	$217.46	$192.67 - $249.00
Q4 2021	10,983	$2,635	$257.12	$221.72 - $290.76
Q3 2021	11,740	$3,322	$327.75	$282.64 - $372.12
Q2 2021	11,740	$4,065	$302.94	$257.03 - $468.55
Q1 2021	81,230	$22,724	$269.69	$238.40 - $296.38
Q4 2020	12,990	$3,181	$259.08	$223.25 - $363.92
Q3 2020	14,490	$4,111	$278.91	$261.87 - $312.00
Q2 2020	17,090	$4,572	$300.59	$257.60 - $350.24
Q1 2020	52,860	$16,724	$303.47	$262.25 - $374.99
Q4 2019	123,740	$36,717	$277.46	$219.70 - $318.00
Q3 2019	57,110	$13,296	$232.85	$215.78 - $246.99
Q2 2019	56,510	$13,216	$230.90	$219.20 - $245.35
Q1 2019	89,260	$21,099	$314.89	$216.12 - $344.00
Q4 2018	106,279	$31,981	$319.14	$278.46 - $358.41
Q3 2018	103,409	$36,535	$344.30	$288.13 - $388.67
Q2 2018	87,609	$25,427	$281.15	$249.17 - $310.91
Q1 2018	87,609	$23,989	$310.41	$259.76 - $370.57
Q4 2017	55,759	$17,763	$320.80	$301.81 - $348.84
Q3 2017	59,340	$18,580	$296.11	$269.50 - $330.00
Q2 2017	24,040	$6,523	$264.42	$244.28 - $291.90
Q1 2017	57,777	$15,798	$282.75	$260.50 - $301.42
Q4 2016	60,177	$17,065	$296.43	$268.00 - $329.83
Q3 2016	74,861	$23,433	$296.18	$240.07 - $333.65
Q2 2016	37,314	$9,023	$263.54	$223.02 - $292.69
Q1 2016	38,914	$10,130	$264.15	$242.07 - $301.02
Q4 2015	40,834	$12,509	$287.35	$254.00 - $311.65
Q3 2015	42,294	$12,342	$330.23	$265.00 - $412.24
Q2 2015	46,534	$18,797	$401.33	$368.88 - $432.88
Q1 2015	49,034	$20,704	$394.14	$334.40 - $480.18
Q4 2014	35,940	$12,200	$323.51	$290.85 - $361.93
Q3 2014	35,740	$11,823	$329.72	$298.31 - $349.00
Q2 2014	57,848	$18,240	$300.97	$272.02 - $322.25
Q1 2014	60,448	$18,489	$317.43	$270.62 - $358.89
Q4 2013	61,348	$17,151	$258.65	$221.07 - $298.82
Q3 2013	64,878	$15,620	$223.81	$203.55 - $248.95
Q2 2013	67,678	$14,565	$213.68	$191.80 - $242.64