BR-CO-09 — E-Invoice Validation Rule & Fix

Fixture ID: unprefixedVat · XPath: /ubl:Invoice/cac:AccountingSupplierParty/cac:Party/cac:PartyTaxScheme/cbc:CompanyID

1. Why This Rule Triggers (Diagnostic Message)

The seller VAT identifier (BT-31) must start with a country prefix in accordance with ISO 3166-1 alpha-2, but "123456789" does not. Greece is the one exception: it uses the prefix "EL" rather than "GR".

2. How to Fix BR-CO-09

Prefix the number with the issuing country's two-letter code — a German number 123456789 becomes "DE123456789". Store it prefixed; do not add the prefix only at render time.

3. Valid Code / Payload Example

"vatId": "DE123456789"