BR-O-12
An Invoice that contains a VAT breakdown group (BG-23) with a VAT category code (BT-118) "Not subject to VAT" shall not contain an Invoice line (BG-25) where the Invoiced item VAT category code (BT-151) is not "Not subject to VAT".
What the rule checks
As the rule set's publisher wrote it. The rule runs on every element the context matches, and fails where the test is false; the validator reports the line of that element.
/ubl:Invoice | /cn:CreditNote
(exists(cac:TaxTotal/cac:TaxSubtotal/cac:TaxCategory[cac:TaxScheme/normalize-space(upper-case(cbc:ID))='VAT']/cbc:ID[normalize-space(.) = 'O']) and count(//cac:ClassifiedTaxCategory[normalize-space(cbc:ID) != 'O'][cac:TaxScheme/normalize-space(upper-case(cbc:ID))='VAT']) = 0) or not(cac:TaxTotal/cac:TaxSubtotal/cac:TaxCategory[cac:TaxScheme/normalize-space(upper-case(cbc:ID))='VAT']/cbc:ID[normalize-space(.) = 'O'])
Checked with EN 16931 Invoice (UBL), EN 16931 Credit Note (UBL), Croatia eRačun Invoice (UBL), Croatia eRačun Credit Note (UBL)
//rsm:SupplyChainTradeTransaction/ram:ApplicableHeaderTradeSettlement/ram:ApplicableTradeTax[ram:CategoryCode = 'O'][upper-case(ram:TypeCode) = 'VAT']
not(//ram:ApplicableTradeTax[ram:CategoryCode != 'O'])
Checked with EN 16931 Invoice (CII)
//rsm:SupplyChainTradeTransaction/ram:ApplicableHeaderTradeSettlement/ram:ApplicableTradeTax[ram:CategoryCode = 'O']
not(//ram:ApplicableTradeTax[ram:CategoryCode != 'O'])
Checked with France Factur-X EN 16931, Factur-X / ZUGFeRD EN 16931