processingInformation. enablerId

This field is the Enabler Verification Value (EVV) that Visa assigns to identify an enabler.

Instead of using acquirers, some merchants use enablers to process payments. Enablers are third parties with their own systems to process transactions for merchants or acquirers. This EVV is an optional five-character hexadecimal value that Visa assigns to identify the enabler that processes requests for authorization and OCT services. If the wrong enabler ID is used in a transaction, the transaction is still accepted. If the enabler ID character string is longer than five characters, the transaction is declined.

The agent unique ID data is still supported in the TC 33 capture file in the first five positions:

The five positions that follow the agent unique ID in CP12 TCR1 are used for the EVV. The final position is reserved for 0. Except for the first digit which is fixed, CP12-TCR1 positions 138-148 () now occupy all of ISO field 126.18.