Good explanation RBT. My understanding was they didn't have to post any amount if there was already a quantity holding the price. If there is none, they must post it. There might be 15 specialists and MM's sitting on different servers waiting for the quotron hub server to route orders by them searching each server for a buy or sell to fill an existing request. If it's being held electronically by the MM, the volume is not added to the quotron volume numbers when it sweeps by their servers in sequence. If a buy matches their sell, it transacts automatically adding to the volume total. Where the specialist's server sits on the router's hub, #1 or #15, determines the transaction pecking order.
Does that jive with your understanding?
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