select whether defined per issuer / holder or whether in holding or transaction
(note: if in holding or transaction, issuer, holder and instrument are already known)
select if per instrument or per instrument_type
this only applies if not tied to a holding or transaction
check if pertaining to a deal instrument or instrument type
(this is to be selected if the item corresponds to a deal vehicle and within that deal there is also an exclusive link to the deal in relation to the instrument or instrument type)