I believe that EDGX does, but without meaning to upset you, I'd respectfully suggest that you'd get a more meaningful/applicable clarification...
Just a minor point of clarification, if I may. The gentlemen who posted previously is correct that Penson clears many Lightspeed accounts, and...
The answer could depend, in part, what trading platform you are originating your orders on. Usually the different market centers provide that...
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