BlackRock Advisors’s Biogen BIIB Stock Holding History

Quarter	Market Value	Status	Shares	Shares Change %	Trade Value	Portfolio Weight	Portfolio Position
2016 Q4	$411M	Buy	1,448,464 +257,964	+22%	+$73.2M	0.42%	48
2016 Q3	$373M	Buy	1,190,500 +128,533	+12%	+$40.2M	0.38%	58
2016 Q2	$257M	Sell	1,061,967 -8,080	-0.8%	-$1.95M	0.26%	90
2016 Q1	$279M	Sell	1,070,047 -286,524	-21%	-$74.6M	0.29%	80
2015 Q4	$416M	Sell	1,356,571 -202,049	-13%	-$61.9M	0.44%	54
2015 Q3	$455M	Buy	1,558,620 +755,770	+94%	+$221M	0.49%	40
2015 Q2	$324M	Buy	802,850 +77,722	+11%	+$31.4M	0.34%	79
2015 Q1	$306M	Sell	725,128 -55,059	-7%	-$23.2M	0.31%	82
2014 Q4	$265M	Sell	780,187 -745,660	-49%	-$253M	0.27%	95
2014 Q3	$505M	Sell	1,525,847 -274,019	-15%	-$90.6M	0.5%	43
2014 Q2	$568M	Buy	1,799,866 +339,384	+23%	+$107M	0.54%	37
2014 Q1	$447M	Buy	1,460,482 +468,965	+47%	+$143M	0.44%	51
2013 Q4	$277M	Buy	991,517 +11,411	+1%	+$3.19M	0.27%	91
2013 Q3	$236M	Buy	980,106 +155,331	+19%	+$37.4M	0.24%	106
2013 Q2	$177M	Buy	+824,775	New	+$177M	0.19%	128