Versioning of FHIR Data A payer SHOULD provide the most recent version of the Patient, Practitioner, Organization and Location resources. A payer MAY choose to support FHIR resource data versioning in their API including Patient, Practitioner, Organization and Location resources. In such cases resources should follow the [vread] ( https://www.hl7.org/fhir/http.html#vread ) guidance in the HTTP section of the FHIR specification. If a payer chooses to support FHIR resource data versioning of related resource references in the referring resource SHALL use the vread format of reference: [type] / [id] /_history/ [vid] Supporting versioning of FHIR data implies supporting the [vread] ( https://www.hl7.org/fhir/http.html#vread ) and [history] ( [vread] ( https://www.hl7.org/fhir/http.html#history ) interactions in the FHIR specification.