{
  "id": "BR-CO-26",
  "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": "In order for the buyer to automatically identify a supplier, the Seller identifier (BT-29), the Seller legal registration identifier (BT-30) and/or the Seller VAT identifier (BT-31) shall be present.",
  "statement_lang": "en",
  "context": "cac:AccountingSupplierParty",
  "test": "exists(cac:Party/cac:PartyTaxScheme[cac:TaxScheme/normalize-space(upper-case(cbc:ID))='VAT']/cbc:CompanyID) or exists(cac:Party/cac:PartyIdentification/cbc:ID[not(@schemeID = 'SEPA')]) or exists(cac:Party/cac:PartyLegalEntity/cbc:CompanyID)",
  "meaning": "The seller identifier (BT-29), the seller legal registration identifier (BT-30), or the seller VAT identifier (BT-31) must be present so the buyer can identify the supplier. The statement says \"and/or\" and \"shall be present\", and it ends with a period. The rule page has a trailing U+00A0 after that period. Collapse drops it. The context is the accounting supplier party. The published test calls exists three times. The VAT scheme comparison is cbc:ID))='VAT' with no space before =. The party-identification branch excludes schemeID SEPA, with spaces around =.",
  "fix": "Send a Seller identifier (BT-29), a Seller legal registration identifier (BT-30), or a Seller VAT identifier (BT-31). A party identification with scheme SEPA does not satisfy the identifier branch.",
  "example_fail": "The seller has no identifier, no legal registration identifier, and no VAT identifier.",
  "example_pass": "The seller has a VAT identifier and no other seller 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-CO-26/",
  "source_retrieved": "2026-10-18",
  "last_verified": "2026-10-18"
}