Sell limit orders must be placed above the market price in order to be accepted. Does this mean that sell limit orders placed before the market opens must be placed above the previous day's close, or above the current day's open? Eg, current day's opening price is significantly below previous day's close. A sell limit order is placed a few minutes before market open at a limit price that is below the previous day's close, but well above the subsequent opening price. Contracts are pit traded, not electronic. Is this order unacceptable because the limit is below previous close? Thank you.