PEPPOL-EN16931-R121 — E-Invoice Validation Rule & Fix

Fixture ID: peppolBaseQuantityZero · XPath: /ubl:Invoice/cac:InvoiceLine[1]/cac:Price/cbc:BaseQuantity

1. Why This Rule Triggers (Diagnostic Message)

Line 1 has an item price base quantity (BT-149) of 0, and Peppol requires it to be a positive number above zero. BT-149 is the denominator of the price: it says "the unit price is for this many units", which is how you quote 12.50 per 100 sheets instead of 0.125 per sheet. Zero would make the line net amount a division by zero, and a negative base would silently invert the sign of the line. Core EN 16931 has no rule on this at all, which is precisely why documents with a zero base reach validators that then fail on the arithmetic instead, reporting BR-CO-10 and sending the reader to the wrong place. This is a Peppol BIS Billing 3.0 profile rule: it applies because profile is "peppol-bis-3". It does not apply to the en16931, xrechnung-ubl or xrechnung-cii profiles, whose validators will accept the same document.

2. How to Fix PEPPOL-EN16931-R121

Set lines[0].baseQuantity to the number of units the unit price covers — 1 in the ordinary case, in which case you can simply omit it. If you meant the invoiced quantity, that is lines[0].quantity, a different term.

3. Valid Code / Payload Example

"unitPrice": 12.5, "baseQuantity": 100, "quantity": 250