70

Tag 70 is the constructed BER-TLV template that wraps the actual contents of one record the terminal retrieves via READ RECORD - in practice, it's the single most common container on the card: nearly every application data element covered elsewhere in this dictionary (the PAN in 5A, Track 2 Equivalent Data in 57, the AFL-referenced records themselves in 94) arrives nested inside one or more of these templates rather than as loose top-level tags. It's closely related to template 77, the modern GENERATE AC response format, which nests its own primitive tags directly rather than going through 70 - the two represent EMV's two different constructed-template conventions for the same underlying idea, one for reading stored records, one for the cryptogram response. Because 70 is a container rather than a primitive value, a parser bug here doesn't look like a wrong value in any one field; it looks like several unrelated fields simultaneously going missing or misreading, which is usually the tell that the bug is in the outer TLV nesting logic, not in any of the individual data elements it happened to contain. See EMV 4.4 Book 3.