BIOGEN INC

Ticker: BIIB CUSIP: 09062X103 Class: COM

WELCH & FORBES LLC's Holding History (CIK: 0000105495)

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

Q3 2021

Shares 776 Value ($000) $220 Avg Close $327.75 Range $282.64 - $372.12

Q2 2021

Shares 926 Value ($000) $321 Avg Close $302.94 Range $257.03 - $468.55

Q1 2021

Shares 1,591 Value ($000) $446 Avg Close $269.69 Range $238.40 - $296.38

Q4 2020

Shares 1,651 Value ($000) $404 Avg Close $259.08 Range $223.25 - $363.92

Q3 2020

Shares 1,651 Value ($000) $468 Avg Close $278.91 Range $261.87 - $312.00

Q2 2020

Shares 1,651 Value ($000) $442 Avg Close $300.59 Range $257.60 - $350.24

Q1 2020

Shares 2,051 Value ($000) $649 Avg Close $303.47 Range $262.25 - $374.99

Q4 2019

Shares 2,046 Value ($000) $607 Avg Close $277.46 Range $219.70 - $318.00

Q3 2019

Shares 2,321 Value ($000) $540 Avg Close $232.85 Range $215.78 - $246.99

Q2 2019

Shares 2,581 Value ($000) $603 Avg Close $230.90 Range $219.20 - $245.35

Q1 2019

Shares 3,546 Value ($000) $838 Avg Close $314.89 Range $216.12 - $344.00

Q4 2018

Shares 6,743 Value ($000) $2,029 Avg Close $319.14 Range $278.46 - $358.41

Q3 2018

Shares 6,983 Value ($000) $2,468 Avg Close $344.30 Range $288.13 - $388.67

Q2 2018

Shares 7,940 Value ($000) $2,305 Avg Close $281.15 Range $249.17 - $310.91

Q1 2018

Shares 7,884 Value ($000) $2,159 Avg Close $310.41 Range $259.76 - $370.57

Q4 2017

Shares 7,243 Value ($000) $2,308 Avg Close $320.80 Range $301.81 - $348.84

Q3 2017

Shares 7,666 Value ($000) $2,400 Avg Close $296.11 Range $269.50 - $330.00

Q2 2017

Shares 7,899 Value ($000) $2,143 Avg Close $264.42 Range $244.28 - $291.90

Q1 2017

Shares 12,972 Value ($000) $3,547 Avg Close $282.75 Range $260.50 - $301.42

Q4 2016

Shares 14,348 Value ($000) $4,068 Avg Close $296.43 Range $268.00 - $329.83

Q3 2016

Shares 14,973 Value ($000) $4,687 Avg Close $296.18 Range $240.07 - $333.65

Q2 2016

Shares 15,243 Value ($000) $3,686 Avg Close $263.54 Range $223.02 - $292.69

Q1 2016

Shares 12,880 Value ($000) $3,354 Avg Close $264.15 Range $242.07 - $301.02

Q4 2015

Shares 11,086 Value ($000) $3,396 Avg Close $287.35 Range $254.00 - $311.65

Q3 2015

Shares 13,498 Value ($000) $3,939 Avg Close $330.23 Range $265.00 - $412.24

Q2 2015

Shares 14,218 Value ($000) $5,743 Avg Close $401.33 Range $368.88 - $432.88

Q1 2015

Shares 13,235 Value ($000) $5,588 Avg Close $394.14 Range $334.40 - $480.18

Q4 2014

Shares 5,114 Value ($000) $1,736 Avg Close $323.51 Range $290.85 - $361.93

Q3 2014

Shares 5,143 Value ($000) $1,701 Avg Close $329.72 Range $298.31 - $349.00

Q2 2014

Shares 4,996 Value ($000) $1,576 Avg Close $300.97 Range $272.02 - $322.25

Q1 2014

Shares 4,918 Value ($000) $1,505 Avg Close $317.43 Range $270.62 - $358.89

Q4 2013

Shares 4,918 Value ($000) $1,375 Avg Close $258.65 Range $221.07 - $298.82

Q3 2013

Shares 5,215 Value ($000) $1,255 Avg Close $223.81 Range $203.55 - $248.95

Q2 2013

Shares 3,900 Value ($000) $840 Avg Close $213.68 Range $191.80 - $242.64

Period	Shares	Value ($000)	Average Close	Price Range
Q3 2021	776	$220	$327.75	$282.64 - $372.12
Q2 2021	926	$321	$302.94	$257.03 - $468.55
Q1 2021	1,591	$446	$269.69	$238.40 - $296.38
Q4 2020	1,651	$404	$259.08	$223.25 - $363.92
Q3 2020	1,651	$468	$278.91	$261.87 - $312.00
Q2 2020	1,651	$442	$300.59	$257.60 - $350.24
Q1 2020	2,051	$649	$303.47	$262.25 - $374.99
Q4 2019	2,046	$607	$277.46	$219.70 - $318.00
Q3 2019	2,321	$540	$232.85	$215.78 - $246.99
Q2 2019	2,581	$603	$230.90	$219.20 - $245.35
Q1 2019	3,546	$838	$314.89	$216.12 - $344.00
Q4 2018	6,743	$2,029	$319.14	$278.46 - $358.41
Q3 2018	6,983	$2,468	$344.30	$288.13 - $388.67
Q2 2018	7,940	$2,305	$281.15	$249.17 - $310.91
Q1 2018	7,884	$2,159	$310.41	$259.76 - $370.57
Q4 2017	7,243	$2,308	$320.80	$301.81 - $348.84
Q3 2017	7,666	$2,400	$296.11	$269.50 - $330.00
Q2 2017	7,899	$2,143	$264.42	$244.28 - $291.90
Q1 2017	12,972	$3,547	$282.75	$260.50 - $301.42
Q4 2016	14,348	$4,068	$296.43	$268.00 - $329.83
Q3 2016	14,973	$4,687	$296.18	$240.07 - $333.65
Q2 2016	15,243	$3,686	$263.54	$223.02 - $292.69
Q1 2016	12,880	$3,354	$264.15	$242.07 - $301.02
Q4 2015	11,086	$3,396	$287.35	$254.00 - $311.65
Q3 2015	13,498	$3,939	$330.23	$265.00 - $412.24
Q2 2015	14,218	$5,743	$401.33	$368.88 - $432.88
Q1 2015	13,235	$5,588	$394.14	$334.40 - $480.18
Q4 2014	5,114	$1,736	$323.51	$290.85 - $361.93
Q3 2014	5,143	$1,701	$329.72	$298.31 - $349.00
Q2 2014	4,996	$1,576	$300.97	$272.02 - $322.25
Q1 2014	4,918	$1,505	$317.43	$270.62 - $358.89
Q4 2013	4,918	$1,375	$258.65	$221.07 - $298.82
Q3 2013	5,215	$1,255	$223.81	$203.55 - $248.95
Q2 2013	3,900	$840	$213.68	$191.80 - $242.64