An Invoice that contains an Invoice line (ibg-25), a Document level allowance (ibg-20) or a Document level charge (ibg-21) where the Tax category code (ibt-151, ibt-095, ibt-102) is “O (Outside of scope of tax)” shall contain exactly one Tax breakdown (ibg-23) with Tax category code(ibt-118) equal to “O”.
/*/cac:TaxTotal/cac:TaxSubtotal/cac:TaxCategory[normalize-space(cbc:ID) = 'O'][cac:TaxScheme/normalize-space(upper-case(cbc:ID))='VAT']((exists(//cac:TaxCategory[cac:TaxScheme/normalize-space(upper-case(cbc:ID))='VAT']/cbc:ID[normalize-space(.) = 'O']) or exists(//cac:ClassifiedTaxCategory[cac:TaxScheme/normalize-space(upper-case(cbc:ID))='VAT']/cbc:ID[normalize-space(.) = 'O'])) and (count(cac:TaxTotal/cac:TaxSubtotal/cac:TaxCategory[cac:TaxScheme/normalize-space(upper-case(cbc:ID))='VAT']/cbc:ID[normalize-space(.) = 'O']) = 1)) or (not(//cac:TaxCategory[cac:TaxScheme/normalize-space(upper-case(cbc:ID))='VAT']/cbc:ID[normalize-space(.) = 'O']) and not(//cac:ClassifiedTaxCategory[cac:TaxScheme/normalize-space(upper-case(cbc:ID))='VAT']/cbc:ID[normalize-space(.) = 'O']))