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

Iridium Communications Inc (symbol: IRDM) was one of the worst losers of
the trading day today (2016-09-06), losing -5.78%. The number of shares
that changed hands was 3,176,330, or about 5 times the average daily volume
in the stock.
The closing price was $7.17, amounting to a market cap of $685,650,000,
about -23.48% off the highest price in the last 12 months. The stock has
been trading at a range between $5.85 and $9.37.
IRDM is in the Telecommunications Equipment industry, part of the Consumer
Durables sector.