Identifies currency used for price or quantity fields, depending on the asset class being traded. CurrencyCodeSource(2897) may be used to disambiguate the code source scheme used, and ISO 4217 is the default scheme if absent.
Absence of this field is interpreted as the default currency for the security as defined by the respective reference data. It is recommended that systems provide the currency value whenever possible.

For securities trading and digital assets traded securities-style, identifies the currency used to denote the price. Absence of this field is interpreted as the default for the security. For Foreign Exchange (FX) and digital assets traded FX-style, identifies the dealt currency used to denominate the quantity related field(s).