Field SecuritySubType (762) - FIX Protocol FIX.5.0SP2
Sub-type qualification/identification of the SecurityType. As an example for SecurityType (167)="REPO", the SecuritySubType="General Collateral" can be used to further specify the type of REPO. If SecuritySubType is used then SecurityType is required. For SecurityType="MLEG" a name of the option or futures strategy name can be specified, such as "Calendar", "Vertical", "Butterfly".
Added in protocol FIX.4.4