BIOGEN INC

Ticker: BIIB CUSIP: 09062X103 Class: COM

Rock Springs Capital Management LP's Holding History (CIK: 0001595725)

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

Q2 2021

Shares 113,500 Value ($000) $39,302 Avg Close $302.94 Range $257.03 - $468.55

Q1 2021

Shares 113,500 Value ($000) $31,752 Avg Close $269.69 Range $238.40 - $296.38

Q4 2020

Shares 100,000 Value ($000) $24,486 Avg Close $259.08 Range $223.25 - $363.92

Q3 2020

Shares 172,500 Value ($000) $48,935 Avg Close $278.91 Range $261.87 - $312.00

Q2 2020

Shares 180,000 Value ($000) $48,159 Avg Close $300.59 Range $257.60 - $350.24

Q1 2020

Shares 180,000 Value ($000) $56,948 Avg Close $303.47 Range $262.25 - $374.99

Q4 2018

Shares 50,000 Value ($000) $15,046 Avg Close $319.14 Range $278.46 - $358.41

Q3 2018

Shares 50,000 Value ($000) $17,666 Avg Close $344.30 Range $288.13 - $388.67

Q2 2018

Shares 53,000 Value ($000) $15,383 Avg Close $281.15 Range $249.17 - $310.91

Q1 2018

Shares 53,000 Value ($000) $14,512 Avg Close $310.41 Range $259.76 - $370.57

Q4 2017

Shares 53,000 Value ($000) $16,884 Avg Close $320.80 Range $301.81 - $348.84

Q3 2017

Shares 53,000 Value ($000) $16,595 Avg Close $296.11 Range $269.50 - $330.00

Q2 2017

Shares 53,000 Value ($000) $14,382 Avg Close $264.42 Range $244.28 - $291.90

Q1 2017

Shares 48,000 Value ($000) $13,124 Avg Close $282.75 Range $260.50 - $301.42

Q4 2016

Shares 47,000 Value ($000) $13,328 Avg Close $296.43 Range $268.00 - $329.83

Q3 2016

Shares 58,000 Value ($000) $18,156 Avg Close $296.18 Range $240.07 - $333.65

Q2 2016

Shares 57,650 Value ($000) $13,941 Avg Close $263.54 Range $223.02 - $292.69

Q1 2016

Shares 53,150 Value ($000) $13,836 Avg Close $264.15 Range $242.07 - $301.02

Q4 2015

Shares 50,650 Value ($000) $15,517 Avg Close $287.35 Range $254.00 - $311.65

Q3 2015

Shares 38,650 Value ($000) $11,278 Avg Close $330.23 Range $265.00 - $412.24

Q2 2015

Shares 38,650 Value ($000) $15,612 Avg Close $401.33 Range $368.88 - $432.88

Q1 2015

Shares 37,000 Value ($000) $15,623 Avg Close $394.14 Range $334.40 - $480.18

Q4 2014

Shares 45,500 Value ($000) $15,445 Avg Close $323.51 Range $290.85 - $361.93

Q3 2014

Shares 61,350 Value ($000) $20,295 Avg Close $329.72 Range $298.31 - $349.00

Q2 2014

Shares 60,000 Value ($000) $18,919 Avg Close $300.97 Range $272.02 - $322.25

Q1 2014

Shares 55,250 Value ($000) $16,899 Avg Close $317.43 Range $270.62 - $358.89

Q4 2013

Shares 53,000 Value ($000) $14,827 Avg Close $258.65 Range $221.07 - $298.82

Period	Shares	Value ($000)	Average Close	Price Range
Q2 2021	113,500	$39,302	$302.94	$257.03 - $468.55
Q1 2021	113,500	$31,752	$269.69	$238.40 - $296.38
Q4 2020	100,000	$24,486	$259.08	$223.25 - $363.92
Q3 2020	172,500	$48,935	$278.91	$261.87 - $312.00
Q2 2020	180,000	$48,159	$300.59	$257.60 - $350.24
Q1 2020	180,000	$56,948	$303.47	$262.25 - $374.99
Q4 2018	50,000	$15,046	$319.14	$278.46 - $358.41
Q3 2018	50,000	$17,666	$344.30	$288.13 - $388.67
Q2 2018	53,000	$15,383	$281.15	$249.17 - $310.91
Q1 2018	53,000	$14,512	$310.41	$259.76 - $370.57
Q4 2017	53,000	$16,884	$320.80	$301.81 - $348.84
Q3 2017	53,000	$16,595	$296.11	$269.50 - $330.00
Q2 2017	53,000	$14,382	$264.42	$244.28 - $291.90
Q1 2017	48,000	$13,124	$282.75	$260.50 - $301.42
Q4 2016	47,000	$13,328	$296.43	$268.00 - $329.83
Q3 2016	58,000	$18,156	$296.18	$240.07 - $333.65
Q2 2016	57,650	$13,941	$263.54	$223.02 - $292.69
Q1 2016	53,150	$13,836	$264.15	$242.07 - $301.02
Q4 2015	50,650	$15,517	$287.35	$254.00 - $311.65
Q3 2015	38,650	$11,278	$330.23	$265.00 - $412.24
Q2 2015	38,650	$15,612	$401.33	$368.88 - $432.88
Q1 2015	37,000	$15,623	$394.14	$334.40 - $480.18
Q4 2014	45,500	$15,445	$323.51	$290.85 - $361.93
Q3 2014	61,350	$20,295	$329.72	$298.31 - $349.00
Q2 2014	60,000	$18,919	$300.97	$272.02 - $322.25
Q1 2014	55,250	$16,899	$317.43	$270.62 - $358.89
Q4 2013	53,000	$14,827	$258.65	$221.07 - $298.82