Let's say I'm watching T&S for ES, and I see a single transaction for 100 contracts at the bid. Now, in all likelihood there was not one person selling 100 and one person buying 100. Rather there was probably one person on one side of the transaction and several people on the other. Is there a convention in the way that transactions are reported in T&S that makes it possible to determine on which side of the trade the one person was acting (e.g., the volume reported always reflects the seller's size, or vice versa)? Thank you. Regards,