{
  "id": "BR-21",
  "country": "EU",
  "syntax": "ubl",
  "group": "document",
  "severity": "fatal",
  "severity_note": "fatal, from the Flag column of the Peppol BIS Billing 3.0 UBL rules index retrieved 2026-10-18.",
  "spec": "Peppol BIS Billing 3.0, May 2026 release, EN 16931 model bound to UBL",
  "statement": "Each Invoice line (BG-25) shall have an Invoice line identifier (BT-126).",
  "statement_lang": "en",
  "context": "cac:InvoiceLine | cac:CreditNoteLine",
  "test": "normalize-space(cbc:ID) != ''",
  "meaning": "Each invoice line (BG-25) must have an invoice line identifier (BT-126). The message says \"shall have\" and starts with \"Each\". It ends with a period. The context is the invoice line or the credit note line. The published test checks that the line identifier is not blank. The comparison is != '' with a space.",
  "fix": "Put a non-blank identifier (BT-126) on each invoice line or credit note line.",
  "example_fail": "An invoice line or a credit note line has no identifier, or that identifier is blank.",
  "example_pass": "The invoice line or the credit note line has a non-blank identifier.",
  "example_note": "Illustration of the condition in the official statement. Not an example published by the source.",
  "source_url": "https://docs.peppol.eu/poacc/billing/3.0/rules/ubl-tc434/BR-21/",
  "source_retrieved": "2026-10-18",
  "last_verified": "2026-10-18"
}