Time priority with show only order

Discussion in 'Order Execution' started by smoss, Oct 31, 2004.

  1. smoss


    When using a "show only" order with an ECN (i.e. buy 500, show only 100) does the entire 500 shares maintain the time priority the initial order is received, or does just the 1st 100 shares get that time priority, with the remaining blocks being restamped after the 1st 100 are sold? Hence, if you do the above order, and someone else subsequently enters another buy order at the same price on the same ECN, and then a matching sell order comes through for say 200 shares, do all 200 shares go to you, or just 100, then 100 to the other person, with your remaining 400 put in as new order with a new time?
    Can't find this answer anywhere on the ECN websites!
    Anyone know??? And is it the same for all the ECN's that allow show only orders?
  2. mnx


    I'm pretty sure that you loose time priority when you use a 'reserve' order. I've posted bids/offers on inet behind reserve orders and been filled for everything and after I am filled the reserve order is still there...

    hope that helps.

  3. Htrader

    Htrader Guest

    When your reserve quote refreshes, you automatically move to the back of the line. Thats the price you pay for being able to hide size.
  4. If someone using ARCA is hiding 1000 shares and showing 100 to buy,won't another arca order to sell 1000 hit that whole arca order before it hits other ecn's and market makers?I always thought that an ecn would fully trade with its own ecn before moving on to other ecn's and market makers?
  5. smoss


    Thanks all.
  6. smoss


    Any new info on this topic? I have been avoiding show only/reserve orders for some time now due to general belief you lose time priority after first piece is filled, however, in my close watching and trading, it seems that if I join someone else on arca at the bid, and he has only 100 showing with a lot in reserve, my order will NOT be hit until his full amount is exhausted.
  7. alanm


    AFAIK, on ARCA, if there is an existing 10000-share bid showing only 100, and you join the bid with a 1000-share order, showing 100, and a sell order for 1000 hits the bid, the other guy will get 100, then you will get 100, then he will get another 100, etc. If you were showing 200, the other guy gets 100 first, then you get 200, then he gets 100, etc.