A normal affect of stock price during a major announcement. It even has a name '"buy the rumor, sell the news" http://www.investopedia.com/terms/n/news-trader

A normal affect of stock price during a major announcement. It even has a name '"buy the rumor, sell the news" http://www.investopedia.com/terms/n/news-trader.asp http://www.investopedia.com/terms/n/news-trader.asp The idea behind this, simply put, is that if you are in a trade for whatever reason with a stock that has a major announcement coming; you are pretty much at the potential peak at announcement time so it is a good time to get out.