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

Mallinckrodt plc Ordinary Share (symbol: MNK) was one of the worst losers
of the trading day today (2015-10-05), losing -6.77%. The number of shares
that changed hands was 3,842,572, or about 2 times the average daily volume
in the stock.
The closing price was $61.41, amounting to a market cap of $7,210,000,000,
about -54.26% off the highest price in the last 12 months. The stock has
been trading at a range between $56.57 and $134.26.
MNK is in the Major Pharmaceuticals industry, part of the Health Care
sector. It first went public in 2013.