ISO 14223-3:2018 describes the information that is stored in the advanced transponder memory, its format and the procedures for accessing such information.
This document defines two parts of memory:
a) the fixed part (mandatory):

ISO 11785 data field,
Data_Config field,

b) the user part (optional):

field of fixed allocation for defined data,
uses an Object Identifier for data field separation in order to have maximum flexibility for future requirements.