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

Imperva, Inc. Common Stock (symbol: IMPV) was one of the worst losers of
the trading day today (2016-02-04), losing -15.41%. The number of shares
that changed hands was 3,271,202, or about 8 times the average daily volume
in the stock.
The closing price was $41.95, amounting to a market cap of $1,320,000,000,
about -46.21% off the highest price in the last 12 months. The stock has
been trading at a range between $38.2 and $77.99.
IMPV is in the Computer Software: Prepackaged Software industry, part of
the Technology sector. It first went public in 2011.