The purpose of storing IDL data on machine-readable media on the IDL is to: increase productivity (of data and IDL use), facilitate electronic data exchange, and assist in authenticity and integrity validation. This document thus specifies the following: mandatory and optional machine-readable data; the logical data structure; encoding rules for the machine-readable technologies currently supported. To prevent unauthorised access to the data contained on a contactless IC (e.g. by eavesdropping), the privacy of the licence holder is protected via basic access protection requiring a human-readable and/or machine-readable key/password on the IDL to access the data on the PIC (via protected-channel communication). The implementation details of this function are defined in ISO/IEC 18013-3.