# PEPPOL-EN16931-R100

> Only one invoiced object is allowed pr line

Checked against Peppol BIS Billing 3.0 2026.5

Canonical: https://einvoicecheck.eu/rules/peppol-en16931-r100

## Official rule text

Only one invoiced object is allowed pr line

## Why did my invoice fail PEPPOL-EN16931-R100?

Each invoice line may reference at most one invoiced object identifier (BT-128), carried in cac:DocumentReference on the line. This keeps the line-level object reference unambiguous, as only a single invoiced object per line is supported by the model.

## Common causes

- An invoice line contains more than one cac:DocumentReference used as an invoiced object reference.
- Multiple object identifiers (e.g. meter ID and contract ID) were both emitted on the same line as DocumentReference.
- Line-level references were duplicated during document merging or aggregation.

## How do I fix it?

```
Limit the line to one object reference: <cac:DocumentReference><cbc:ID schemeID="AAJ">METER-998</cbc:ID></cac:DocumentReference> and remove the extra DocumentReference.
```