These rules are necessary to comply with the EN 16931 eInvoicing standard.
These rules are Peppol specific in Europe for intra jurisdiction invoices and shall be applied by all senders who are creating invoices that shall comply with requirements of that jurisdiction. They are only applied by receivers who have a receiving capability for the jurisdiction invoice. Overseas receivers who are receiving invoices from the jurisdiction but do not have a specific receiving capability for those will only apply the shared PINT rules and ignore these.
These are rules that are shared by all implementation of PINT compliant invoices. If any of these rules fails when validating an invoice message then that invoice is not a valid PINT invoice.