An Invoice that contains a Document level allowance (BG-20) where the Document level allowance VAT category code (BT-95) is "Reverse charge" shall contain the Seller VAT Identifier (BT-31), the Seller tax registration identifier (BT-32) and/or the Seller tax representative VAT identifier (BT-63) and the Buyer VAT identifier (BT-48) and/or the Buyer legal registration identifier (BT-47).
/ubl:Invoice | /cn:CreditNote(exists(//cac:AllowanceCharge[cbc:ChargeIndicator=false()]/cac:TaxCategory[normalize-space(cbc:ID) = 'AE'][cac:TaxScheme/normalize-space(upper-case(cbc:ID))='VAT']) and (exists(//cac:AccountingSupplierParty/cac:Party/cac:PartyTaxScheme/cbc:CompanyID) or exists(//cac:TaxRepresentativeParty/cac:PartyTaxScheme[cac:TaxScheme/(normalize-space(upper-case(cbc:ID)) = 'VAT')]/cbc:CompanyID)) and (exists(//cac:AccountingCustomerParty/cac:Party/cac:PartyTaxScheme[cac:TaxScheme/(normalize-space(upper-case(cbc:ID)) = 'VAT')]/cbc:CompanyID) or exists(//cac:AccountingCustomerParty/cac:Party/cac:PartyLegalEntity/cbc:CompanyID))) or not(exists(//cac:AllowanceCharge[cbc:ChargeIndicator=false()]/cac:TaxCategory[normalize-space(cbc:ID) = 'AE'][cac:TaxScheme/normalize-space(upper-case(cbc:ID))='VAT']))