# UBL-SR-43

> Scheme identifier shall only be used for invoiced object (document type code with value 130 or 50)

Checked against Peppol BIS Billing 3.0 2026.5

Canonical: https://einvoicecheck.eu/rules/ubl-sr-43

## Official rule text

Scheme identifier shall only be used for invoiced object (document type code with value 130 or 50)

## Why did my invoice fail UBL-SR-43?

The scheme identifier attribute (schemeID) on an object identifier is only meaningful for the Invoiced object identifier (BT-18), which is carried in cac:AdditionalDocumentReference where the DocumentTypeCode is 130 (invoicing data sheet) or 50 (referenced object). This rule ensures a schemeID is only supplied in that context, not on ordinary additional document references, so its coded value list is applied correctly.

## Common causes

- A schemeID attribute added to a cac:AdditionalDocumentReference/cbc:ID whose cbc:DocumentTypeCode is not 130 or 50.
- The invoiced object reference omits or mis-sets cbc:DocumentTypeCode while still carrying schemeID.
- A generic attachment reference wrongly given a schemeID.

## How do I fix it?

```
Only use schemeID on the invoiced object reference: <cac:AdditionalDocumentReference><cbc:ID schemeID="AAB">OBJ-123</cbc:ID><cbc:DocumentTypeCode>130</cbc:DocumentTypeCode></cac:AdditionalDocumentReference>; drop schemeID from other document references.
```