Format: bLength: 8Bitmap
DE 65
Tertiary Bitmap
What it is
Bitmap for data elements 129–192. Defined by the standard but essentially unused in production networks.
Specification reference
Defined in ISO 8583:1987 (base). Card networks publish their own dialect tables (Visa BASE I / V.I.P., Mastercard CIS) that refine formats, lengths, and — for private-use elements — the entire layout. Always confirm against the interface specification you implement.