ADV-EMPTY: data quality hint
Empty element
A data quality hint, not part of the official rules. EN 16931, Peppol BIS, XRechnung and Factur-X have no such rule, so an invoice with this hint can be valid. The validator lists hints in a separate section of the result (and in advisories in the API); they never make an invoice invalid.
What this rule checks
An element has no value and no child elements (attributes do not count). EN 16931 has no rule against empty elements, so a plain EN 16931 CII invoice or a Factur-X MINIMUM or BASIC WL invoice with one passes the official rules. Peppol BIS, XRechnung and the Factur-X BASIC, EN 16931 and EXTENDED rules report them (PEPPOL-EN16931-R008), so this hint runs only where that rule does not. Many receivers read an empty element as an error or as a missing value. ram:ApplicableHeaderTradeDelivery is not flagged: the CII schema requires it even without delivery information.
How to fix it
Leave out elements you have no value for, such as an empty ram:SpecifiedLegalOrganization, instead of writing them empty.
Related rules
Check your invoice
Upload your invoice to check it against the official EN 16931, Peppol BIS, XRechnung or Factur-X rules. The result lists data quality hints such as ADV-EMPTY in a separate section; they never make an invoice invalid. Free, instant, no signup.