William Blair Investment Management’s Biogen BIIB Stock Holding History

Bought

Maintained

Sold

Quarter	Market Value	Status	Shares	Change in Stake	Trade Value	Portfolio Weight	Portfolio Position
2019 Q1	–	Sell	-28,149	Closed	-$8.47M	–	409
2018 Q4	$8.47M	Sell	28,149 -39,469	-58%	-$12.6M	0.04%	319
2018 Q3	$23.9M	Sell	67,618 -47,078	-41%	-$16.2M	0.08%	211
2018 Q2	$33.3M	Sell	114,696 -3,502	-3%	-$985K	0.12%	177
2018 Q1	$32.4M	Sell	118,198 -28,427	-19%	-$8.82M	0.12%	174
2017 Q4	$46.7M	Sell	146,625 -4,711	-3%	-$1.51M	0.18%	148
2017 Q3	$47.4M	Sell	151,336 -53,771	-26%	-$15.9M	0.17%	151
2017 Q2	$55.7M	Sell	205,107 -87,940	-30%	-$23.3M	0.2%	129
2017 Q1	$80.1M	Sell	293,047 -142,802	-33%	-$40.4M	0.3%	105
2016 Q4	$124M	Buy	435,849 +4,118	+1%	+$1.22M	0.49%	69
2016 Q3	$135M	Buy	431,731 +67,344	+18%	+$19.9M	0.52%	65
2016 Q2	$88.1M	Sell	364,387 -7,059	-2%	-$1.86M	0.35%	96
2016 Q1	$96.7M	Buy	371,446 +55,652	+18%	+$14.7M	0.38%	90
2015 Q4	$96.7M	Buy	315,794 +73,617	+30%	+$21.2M	0.39%	90
2015 Q3	$70.7M	Buy	+242,177	New	+$80M	0.14%	215