# UBL-SR-10

> Seller trader name shall occur maximum once

Checked against Peppol BIS Billing 3.0 2026.5

Canonical: https://einvoicecheck.eu/rules/ubl-sr-10

## Official rule text

Seller trader name shall occur maximum once

## Why did my invoice fail UBL-SR-10?

The Seller trading name (BT-28), the name the seller commonly trades under if different from the legal name, may occur at most once. In UBL this maps to cac:AccountingSupplierParty/cac:Party/cac:PartyName/cbc:Name, which must not repeat.

## Common causes

- Several cac:PartyName elements are emitted (e.g. one per brand or division).
- Trading name is duplicated from both a DBA field and a marketing name.
- Template outputs the trading name inside a loop over party aliases.

## How do I fix it?

```
Provide a single trading name: <cac:PartyName><cbc:Name>ACME</cbc:Name></cac:PartyName> and delete any additional cac:PartyName elements under the supplier party.
```