I've just started using IB and am generally very pleased. However today I put in an order for 100 shares and got 20 before the stock ran away from me. Is it possible to require that orders be filled totally or not at all? I can't find any reference to "all or none" in the manual.
IB does not offer all or none. Just one cancels all. A few of the ECN's will not do partial fills and thus you could direct your orders explicitly to those ECN's.