ALEXION PHARMACEUTICALS INC

CUSIP: 015351109 Class: COM

Chesley Taft & Associates LLC's Holding History (CIK: 0001164632)

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

Q2 2015
Shares 3,560 Value ($000) $644 Avg Close — Range —
Q1 2015
Shares 3,610 Value ($000) $626 Avg Close — Range —
Q4 2014
Shares 5,303 Value ($000) $981 Avg Close — Range —
Q3 2014
Shares 5,268 Value ($000) $874 Avg Close — Range —
Q2 2014
Shares 5,268 Value ($000) $823 Avg Close — Range —
Q1 2014
Shares 5,550 Value ($000) $844 Avg Close — Range —
Q4 2013
Shares 6,495 Value ($000) $863 Avg Close — Range —
Q3 2013
Shares 6,495 Value ($000) $754 Avg Close — Range —
Q2 2013
Shares 6,470 Value ($000) $597 Avg Close — Range —