Are there cases where where PositionEffect FIX Tag 77 is deemed a regulatory requirement? I tried searching, but have only located corporate FIX specs where it is mandatory.
Yes, the Consolidated Audit Trail (CAT) in the US has a field called openCloseIndicator with the following conditional requirement:
Indicates whether the action taken (buy or sell) will open a new position or will close an existing position in the order originator’s account. Required when the exchange’s rules require an order to be marked as open or close upon entry into the exchange.
Derivative exchanges typically require PositionEffect(77) or similar field (if they are not using FIX semantics).
Thank you.