Hi,
Im getting myself confused as to which tag can be used to indicate that the fix message is a reportable transaction under MiFID II… Is it the combination of 29 & 30 or is down to whether or not 20073 is populated?
I downloaded the MiFID Trading Capacity & FIX Tag 29 document from here: https://www.fixtrading.org/fix-and-mifid/mifid-implementation-guidelines/ and it seems to indicate its the combination or 29&30 but I had thought that 20073 was to be used - if it was blank it was not reportable, populated signified a reportable transaciton…
LastCapacity(29) and LastMkt(30) do not answer the question whether a transaction is reportable. The document you refer to primarily deals with the question of how to find the right value for LastCapacity(29).
PartyIDExecutionVenue(20073) is a market convention shortcut for PartyID(448)=, PartyIDSource(447)=G, PartyRole(452)=73 (ExecutionVenue) for users of FIX 4.2 that are unable to support repeating groups. This only identifies the place of execution and does not explicitly indicate whether a transaction is reportable or not.
There are two guidelines on the page you refer to, one for transaction reporting and one for trade reporting.
The former talks about presence of a venue to be taken as an (implicit) indicator: “It is recommended that the presence of transaction reporting venue be used to denote that an execution message represents a ‘client fill’ and hence a transaction reportable event.”.
The latter identifies an (explicit) indicator TradeReportingIndicator(2524) which was introduced for MiFID to be used between parties to convey trade reporting status.