# PEPPOL-EN16931-P0107

Source: https://xmlvalid.com/rules/PEPPOL-EN16931-P0107

> Tax Category AE MUST be used when exemption reason code is VATEX-EU-AE

- Level: error
- Rule sets: Peppol BIS Billing 3.0 rules 3.0.21
- Context: `cac:TaxCategory[upper-case(cbc:TaxExemptionReasonCode)='VATEX-EU-AE']`
- Test: `normalize-space(cbc:ID)='AE'`

Validate a document against these rules: https://xmlvalid.com/validate