fatalEN 16931EN 16931 business ruleCIIUBLBG-24BT-122
Each Additional supporting document (BG-24) shall contain a Supporting document reference (BT-122).
An additional supporting document group (BG-24) has no document reference (BT-122).
Add BT-122 (UBL AdditionalDocumentReference/cbc:ID). If you attach a file, it still needs an identifier as well as the attachment itself.
CII — context $Additional_supporting_documents
normalize-space(ram:IssuerAssignedID) != ''
UBL — context cac:AdditionalDocumentReference
normalize-space(cbc:ID) != ''
Nothing is stored, and the whole invoice is checked, not just this rule. A PDF only works if it is Factur-X / ZUGFeRD — a PDF with the invoice XML inside it.