Nokia sells units to Microsoft
On 09-03-2013 Microsoft MSFT, announced that it is buying the handset units from Nokia, NOK. Nokia stock moved up over 16 standard deviations on the news. The chart below is a daily chart of Nokia, the red bars show the price move in standard deviations. The line on the bottom is the IV/SV ratio, notice how the implied volatility rose dramatically in the days prior to the announcement, a signal that something was happening.