Lets say that the earnings are positve. It would not be wise to jump in with a market order as you will have plenty of chumps willing to sell for puny profits. If earnings are good you may have an initial spike upward, but the chumps will start to bail after about 30 minutes. That will inturn drive the stock price down presenting you with a much better buy point. Remember, chump sellers are the way to huge wealth. Good luck.