ISO 20022 · External code set

Authority exchange reason codes

Specifies the reason for the exchange with the national competent authority, as published in an external category purpose code list. External code sets can be downloaded from www.iso20022.org.

13 registered codesSource release: August 2026 (v3)

Registered codes in `ExternalAuthorityExchangeReason1Code`. Select a code for its full definition and source details.
Code	Published name and definition
`ADHR`	Ad Hoc Request Ad hoc request.
`CABB`	Competent Authority For Buyer Branch Competent Authority for Buyer Branch.
`CABC`	Competent Authority For Basket Constituant Competent Authority for Basket Constituant.
`CABT`	Competent Authority For Buyer Transmitting Firm Competent Authority for Buyer Transmitting Firm.
`CADB`	Competent Authority For Decision Making Branch Competent Authority for Decision Making Branch.
`CADU`	Competent Authority For Direct Underlying Competent Authority for Direct Underlying.
`CAEB`	Competent Authority For Executing Branch Competent Authority for Executing Branch.
`CAFI`	Competent Authority For Instrument Competent Authority for Instrument.
`CAIX`	Competent Authority For Index Competent Authority for Index.
`CAMB`	Competent Authority For Membership Branch Competent Authority for Membership Branch.
`CASB`	Competent Authority For Seller Branch Competent Authority for Seller Branch.
`CAST`	Competent Authority For Seller Transmitting Firm Competent Authority for Seller Transmitting Firm.
`CATV`	Competent Authority For Trading Venue Competent Authority for Trading Venue.

Message references 2

Versions listed in the source workbook, including older versions. This list does not establish which messages a bank, network or provider supports.

auth.016.001.02Financial Instrument Reporting Transaction Report V02
auth.016.001.03Financial Instrument Reporting Transaction Report V03

Source: UsageInMsgs sheet in 2Q2026_externalcodesets_v3.xlsx.