Not every Bundle.entry requires fullURLs. Specifically, the documentation states, "For transactions and batches, entries MAY not have fullURLs when the entry.request.method = POST, and the resource has no identity."

However, the FHIRPath constraint does not account for this. An empty fullUrl field will cause the constraint to evaluate to an empty collection, which would fail validation.

bdl-8 Rule Bundle.entry fullUrl cannot be a version specific reference fullUrl.contains('/_history/').not()

I'd suggest something along the lines of "fullUrl.exists() implies fullUrl.contains('/_history/').not()" or "fullUrl.all(contains('/_history/').not())