Archived clinical documents reference immutable bytes through an opaque archive handle and revision. The revision is independent of the FHIR resource version. Exactly one PDF, PNG or JPEG attachment describes the content; retrieving bytes and authorizing access remain the responsibility of the archive service.
The patient subject is optional. Its absence represents an unmatched inbox document. When supplied, it uses a relative Patient reference. Custodian and checksum metadata remain optional. Repeated archive extensions are permitted; consumers select the first handle and revision. Each checksum supplies an algorithm and value without imposing a particular algorithm or digest format.
The profile and its four archive extensions preserve their existing canonical identities for compatibility. These exact canonical identifiers are permitted only as structured definitions or references. This does not permit product names in narrative, unrelated identifiers or deployment-specific content.