errorformatEN16931

UBL-SR-17:Buyer legal registration identifier shall occur maximum once

Fix: Your invoice contains multiple Buyer legal registration identifiers (PartyLegalEntity/CompanyID). EN16931 allows only one legal registration ID per buyer.

Your invoice contains multiple Buyer legal registration identifiers (PartyLegalEntity/CompanyID). EN16931 allows only one legal registration ID per buyer.

Severity
Fatal
Rule set
EN16931
Country
All EU
Fix type
CONFIRM
Confidence
90%
Category
structural

Engine Classification

Requires user confirmation before application

What is UBL-SR-17?

UBL-SR-17 is a fatal validation rule defined in the EN16931 specification. It validates the CompanyID element under Party > PartyLegalEntity in the UBL invoice XML.

When this rule fires, the invoice is rejected by Peppol access points and never reaches the buyer.

Target path: /Invoice/cac:AccountingCustomerParty/cac:Party/cac:PartyLegalEntity/cbc:CompanyID

Why This Error Matters

Invoice will be rejected by EN16931 validators. These structural constraints ensure consistent processing by receiving systems.

UBL-SR-17 is a hard failure — the invoice must be corrected and re-sent before it can reach the recipient.

Validator Behavior

  • ·Causes invoice rejection
  • ·Fails EN 16931 business rule validation
  • ·Error returned: UBL-SR-17
  • ·Specification: EN16931

How to Fix It

1.

Locate the duplicate entries

Search for multiple cbc:CompanyID elements at /Invoice/cac:AccountingCustomerParty/cac:Party/cac:PartyLegalEntity/cbc:CompanyID. Only one instance is allowed per the specification.

2.

Remove the duplicates

Your invoice contains multiple Buyer legal registration identifiers (PartyLegalEntity/CompanyID). EN16931 allows only one legal registration ID per buyer.

3.

Re-validate your invoice

Upload the corrected invoice to confirm UBL-SR-17 is resolved.

XML Example

Generic example based on the rule's target XPath. Your actual XML structure may differ.

Before
<!-- Missing or empty element triggers cbc:CompanyID error -->
<cbc:CompanyID></cbc:CompanyID>
After
<!-- Provide the required value -->
<cbc:CompanyID>VALID_VALUE</cbc:CompanyID>

Technical Reference

XPath/Invoice/cac:AccountingCustomerParty/cac:Party/cac:PartyLegalEntity/cbc:CompanyID
SpecEN16931
Operationremove_duplicates
StrategyRemove duplicate buyer legal registration identifiers, keeping the first occurrence

Common Causes

  • ·ERP system exports multiple references where only one is allowed in EN16931
  • ·Data consolidation merged records that should have been deduplicated
  • ·Template or mapping incorrectly configured to output duplicate elements
  • ·Manual editing introduced extra elements
  • ·Invoice conversion from another format did not merge duplicate entries

Seeing this in production? The API handles UBL-SR-17 automatically. See the fix response →

Frequently Asked Questions

Your invoice contains multiple Buyer legal registration identifiers (PartyLegalEntity/CompanyID). EN16931 allows only one legal registration ID per buyer.

Your invoice contains multiple Buyer legal registration identifiers (PartyLegalEntity/CompanyID). EN16931 allows only one legal registration ID per buyer. You can also use Invoice Navigator's compliance engine to correct this automatically in your pipeline.

Yes, UBL-SR-17 is a critical error that will cause invoice rejection. It must be fixed before submission.

Many instances of UBL-SR-17 can be automatically corrected using Invoice Navigator's compliance engine. The fix is applied in your pipeline with full audit evidence.

Related Content

Last updated: 14 April 2026

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