Entering order price close to open price

Discussion in 'Trading' started by clarodina, Jun 9, 2010.

  1. How does US stock exchanges determine the open price of stocks? The open price in the historical data seems to be differ from realtime buy/sell price at the opening time. Which time (pre open time, opening time?) should be appropriate in entering order so that the filled price matches the open price in the historical data following?