buying at the open strange scenario

Discussion in 'Order Execution' started by dumbgai, Oct 24, 2007.

  1. dumbgai


    Say you are trading a low limit stock.
    You set a limit order to sell at 99 dollars. Another person has a limit order to buy for 101 dollars. There are no other order sout there. At what price is this going to get executed?
  2. cszulc


    I'm pretty sure it gets filled at $99, because that is the best available price, unless you cancel your order before the open, and then hit his order to sell at $101.
  3. Since both orders are marketable, you have multiple scenarios here:
    1. If there is no imbalance, the specialist will pair-off orders using the previous closing price (not sure about this price 100% though, anyone confirm?)
    2. If there is any imbalance, the specialist will stop remaining size at the opposite side, and the newly established price would be the opening price.
    3. If there is any imbalance, and there is no liquidity, the specialists have to be on the other side of the imbalance supplying liquidity, or the specialist will just halt/delay the opening.
  4. I am surprised if the broker accepts these orders.

    A limit order to sell has to be placed above the market price. So a limit order to sell at 99 means the current market price, or at least the ask if the exchange is not open for trading, must be less than 99.

    A limit order to buy at 101 means the market price is greater than 101.

    The market price can not be both less than 99 and greater than 101 at the same time.
  5. It's perfectly fine to shoot a buy limit order above the offer price or a sell limit order below the bid price - all market centers would treat them as marketable limit orders. This is very nice alternative to market orders since it allows you control the exposure without sacrificing any execution speed, and you can specify FOK if you don't want your orders to be placed on the book if market moves a lot while your broker accepts your order.