Validation rules

BR-16 — EN 16931 rule

The invoice has no invoice lines (BG-25) — at least one is required.

Rule: BR-16 — official EN 16931 / XRechnung rule
Severity: error
Detected by: tier 3 — KoSIT validator (authoritative)
Reachability: Only reachable when validating your own XML — normbill-generated documents cannot trigger it

invoice.lines requires at least one entry in the request schema; the UBL schema also mandates one, so the XSD tier reports line-less XML first.

How to fix it

Add at least one cac:InvoiceLine.

BR-16 auf Deutsch — was bedeutet der Fehler?

Die Rechnung enthält keine Rechnungspositionen (BG-25) — mindestens eine ist Pflicht.

So beheben Sie den Fehler

Ergänzen Sie mindestens eine cac:InvoiceLine.

Related rules

BR-15 — The amount due for payment (BT-115) is missing from the document totals.
BR-17 — A payee (BG-10) that differs from the seller must state the payee name (BT-59).
BR-14 — The invoice total with VAT (BT-112) is missing from the document totals.
BR-18 — A seller tax representative (BG-11) must state the representative's name (BT-62).
BR-13 — The invoice total without VAT (BT-109) is missing from the document totals.
BR-19 — A seller tax representative (BG-11) must carry a postal address (BG-12).

Official sources

Every 422 from the API lists the rule id, the path in your request JSON, a plain-language message and a suggested fix — see the docs overview for the report format.

Or try it live: drop any XRechnung XML on the free validator — same KoSIT-backed report, no account.