Rule at a Glance
| ID | Severity | Context (XPath) |
|---|---|---|
| Series ref. BR-50 | Fatal (error) | cac:AccountingCustomerParty/cac:Party/cbc:EndpointID |
Schematron ID: ibr-063 | Field: @schemeID on the Buyer electronic address (IBT-049) |
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Classification
Master Data — the failing data sits in the customer master, one record per buyer. Unlike the seller-side twin, a defect here surfaces selectively: invoices to well-maintained customers pass while invoices to customers onboarded before the e-invoicing project fail.
What the Rule Is Checking
The assert text is the mirror of ibr-062: "The Buyer electronic address (ibt-049) MUST have a Scheme identifier." Any cbc:EndpointID under cac:AccountingCustomerParty must carry a schemeID attribute naming the registry the value belongs to. For UAE buyers that scheme is 0235, the UAE TIN.
Why This Rule Exists
The buyer's electronic address is the routing destination of the whole exchange. In the 5-Corner model your Accredited Service Provider queries the Peppol SMP with the buyer's scheme-plus-value pair to discover which Corner 3 provider receives the document. A missing scheme makes that lookup impossible, so the invoice cannot be delivered at all — the validation failure is the network telling you, before transmission, that the address on the envelope is incomplete.
Standard / Code List
The scheme list is the same Peppol EAS registry used for the seller endpoint, covered in Peppol EAS and ICD Participant Identifiers. What differs is where the data lives: one supplier configuration on your side, thousands of customer records on this one.
UAE Data Example
PASSES ✓: <cbc:EndpointID schemeID="0235">9XXXXXXX5</cbc:EndpointID> — the customer's TIN with the scheme declared.
FAILS ✗: A customer record created years ago holds the buyer's TIN in a free-text "tax number" field. The migration script copies the value into the endpoint element but has no scheme column to read, so the attribute is emitted empty or not at all. Every invoice to that customer fails while the rest of the ledger passes, which is what makes the defect slow to surface in testing.
What Your ERP / IT Team Must Ensure
Treat the buyer endpoint as two mandatory columns in the customer master — scheme and value — and reject records at onboarding that populate one without the other. Backfill the scheme for existing UAE customers as a data-cleansing exercise before go-live rather than waiting for rejections to identify the gaps. Sample-based UAT will miss this rule; run the full customer master through the extract once and count how many records emit a schemeID.
Related Rules
The seller-side counterpart is BR-49 (ibr-062). Where a buyer is identified by a GLN under scheme 0088, the format check in BR-53 (ibr-068) applies on top of this one.