Someone may correct me if i'm wrong,but i wasnt aware(according to Don) that market makers can hold Supersoes orders.They don't know that they have been Soes'ed or Supersoes'ed until after they get a fill.Under Soes,MM's have to fill their displayed size once every 17 seconds.Under Supersoes, this delay has been reduced to zero. I know that if preferencing a MM using Selectnet, the MM has up to 30 seconds to either fill you,partial you,or reject your order,but Selectnet is a useless tool in my opinion. I think the Island or Archipelago/Redi ECN's are the way to go nowadays if trading Nasdaq.

).