Defines how an NFC-enabled device in Reader/Writer Mode detects, reads and writes a NDEF Message on a NFC Forum Type 4 Tag. The communication with this Forum Tag type is based on the ISO Data Exchange Protocol (ISO-DEP) which is fully compatible with the ISO/IEC 14443 standard series. This protocol is either based on NFC-A or NFC-B Technology.

Version 1.1 of the Type 4 Tag Specification includes updates to support time-optimized implementations to improve the performance for reading NFC Forum tags in support of the new TNEP protocol.