PTC THERAPEUTICS INC

Ticker: PTCT CUSIP: 69366J200 Class: Common Stock

ESSEX INVESTMENT MANAGEMENT CO LLC's Holding History (CIK: 0000201772)

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

Q3 2015

Shares 17,157 Value ($000) $458 Avg Close $42.77 Range $24.63 - $62.15

Period	Shares	Value ($000)	Average Close	Price Range
Q3 2015	17,157	$458	$42.77	$24.63 - $62.15