ErrorEN 16931Input required

CII-SR-455

DefinedTradeContact of SellerTradeParty shall exist maximum once

What does this rule mean?

DefinedTradeContact of SellerTradeParty shall exist maximum once

A syntax rule binding the EN 16931 requirements to the concrete XML syntax (UBL or CII).

Official rule message (standard)

DefinedTradeContact of SellerTradeParty shall exist maximum once

Where the rule applies

Syntax: CII

Affected element (XPath):

  • /rsm:CrossIndustryInvoice/rsm:SupplyChainTradeTransaction/ram:ApplicableHeaderTradeAgreement

Technical test

The rule passes when this Schematron expression holds true:

( count(ram:SellerTradeParty/ram:DefinedTradeContact)  <= 1)

How to fix it

A missing or incorrect business entry only you can supply. Add or correct it, then re-check.

Adjust the named element/attribute to the syntax requirement.

Correct the affected entry in your XML, then re-check the invoice. Validation runs locally in your browser — your file never leaves your machine.

Check an e-invoice here

Drop an XML or ZUGFeRD PDF file here. Validation runs locally in your browser against EN 16931 — your file never leaves your machine.

100% local — no upload, no account.

Related rules

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