$PTLA is one of biggest losers #stocks today. read more:

Portola Pharmaceuticals, Inc. (symbol: PTLA) was one of the worst losers of
the trading day today (2016-11-08), losing -12.87%. The number of shares
that changed hands was 2,034,576, or about 2 times the average daily volume
in the stock.
The closing price was $16.25, amounting to a market cap of $918,140,000,
about -69.28% off the highest price in the last 12 months. The stock has
been trading at a range between $15.68 and $52.89.
PTLA is in the Major Pharmaceuticals industry, part of the Health Care
sector. It first went public in 2013.