Hi, if two different brokers (say, MB Trading and Lightspeed) clear their options trades through the same clearing firm (say, Penson) should there be any difference in the execution results? Or since they use the same clearing firm all of the orders should be routed the same way and there should not be any difference in execution? I refer specifically to options spread orders and not single orders. Another question -- if the same option spread limit order is sent by different brokers (that do not use the same clearing firm) to the same exchange (say, ISE), should there be any difference in execution (i.e., better price at one broker than the another)? Or since the order just sits on the exchange's servers at this stage then the execution results depend on the exchange and the market makers and not on the brokers anymore?