DDEX makes heavy use of allowed-value sets (aka code lists). This is essential for automated processing of DDEX messages.
There are, however, circumstances where the DDEX-defined list of allowed values does not meet a particular business need. For such cases, DDEX allows to communicate user-defined values:
Namespace attribute needs to carry the DPID of the party controlling
Augmenting an allowed value
Sometimes a user wants to augment a DDEX-defined value with more specific information. The recommended approach is to include two tags with the appropriate values as follows;