Reviewing the List resource: List.entry values are only allowed to communicated item deletion when List.mode is "changes". An ordinary snapshot-mode list can't be used to communicate entry deletions, according to LST-2 ( http://build.fhir.org/list.html#invs). Depending on your use case, you might want to use Group instead of List (if applicable). Group.members can track a period (start + end) of membership. Otherwise, FHIR's List.entry.deleted can only be used in "changes"-mode lists; if you want to track deletion dates for a FHIR List in "snapshot" or "working" mode, we recommend: Do note populate List.entry.deleted (because it's not allowed) Create a value for List.entry.flag to communicate the deletion status Create your own extension to indicate that (and when) an entry has been deleted. (Or if you prefer not to create a List.entry.flag value, then create a modiferExtension to indicate deletion status and date.) If you're using a "changes"-mode List, then List.date should be used to communicate the date of deletion of the List.entries.