LEARN. PRACTICE. GROW.Concept and mechanism
A definition identifier distinguishes business area, definition number, variant, and version. The version published in the catalogue is not necessarily the one used by a scheme or community. The 2025 EPC guidelines, for example, reference 2019 message versions. A project should retain the combination of definition, profile, external lists, extension, and effective date for each interface. The e-Repository can include candidate definitions still under evaluation. Being on an official site does not turn a draft into a production contract. Updating only the namespace does not implement structural, constraint, or interpretation changes required by a new version.
Guided application
A registered variant restricts a global definition and has its own maintenance lifecycle; it is not synonymous with any locally reduced XSD. SupplementaryData requires a registered extension, qualification for the applicable version, and party agreement on usage. A base-message upgrade should review that dependency. For API integration, distinguish resource model from complete API behavior: JSON Schema alone defines neither authentication, retries, nor idempotency. A compatibility matrix supports community-specific migration planning and transformation testing between contracts. Avoid transferring another initiative’s deadline to all ISO 20022 usage. Every decision needs applicable scope and source alongside its date.
Example: two communities use different versions. A common internal model can help if adapters and tests preserve each external contract’s rules and meaning.
Common pitfalls
Newest treated as mandatory everywhere; draft treated as approved version; extension treated as arbitrary content; JSON resource treated as complete API.
Related topics: Semantics and contract documentation · Messages, headers, and states · Layered validation
Version the whole contract and agree migration with its users.
Reference: Catalogue of messages · DR ISO20022 fundamentals professional assessment2026.10