To improve the linkage between the value sset resource that is the result of the $expand operation and the base resource that was used to create the expansion, we suggest the following be added either as an Invariant or whatever is needed.

When executing a $expand, the Valueset.version included in the resulting resource SHALL be the Valueset.version if that element exists in the value set resource used to create the expansion.

Discussed 2019-08-13 VSE call https://confluence.hl7.org/pages/resumedraft.action?draftId=58657375&draftShareId=44bfc2de-018d-46d1-88d2-a16cebc62717&