# BR-DE-18 Seller features must be provided

The seller features must be provided on the invoice.

## Problem Description

The seller features must be provided on the invoice.

> **ERROR**: XRechnung 3.0

## Context and Significance

This rule typically indicates that additional seller identification attributes are required by the target profile (for example, legal identifiers or routing identifiers depending on the delivery channel). Ensure the seller party includes all required identifiers for your scenario.

## Solution

Add the seller features to the invoice.

## Valid Examples

- Seller identifiers provided as required by the profile (e.g., VAT ID, registration ID, endpoint ID)

## Invalid Examples

- Seller identifiers missing while required by the receiver/profile

## Code Examples

### Valid XML
```
<cac:Party>
  <cbc:EndpointID>ENDPOINT_ID_FROM_RECEIVER</cbc:EndpointID>
  <cac:PartyTaxScheme><cbc:CompanyID>DE123456789</cbc:CompanyID></cac:PartyTaxScheme>
</cac:Party>
```

### Invalid XML
```
<!-- Missing required seller identifiers -->
```

## Technical Details

### Affected Fields
Seller Identifiers, Seller Electronic Address

## Related Rules

- [BR-DE-6](/resources/kosit-validator-errors/br-de-6-seller-name-must-be-provided)
- [BR-DE-2](/resources/kosit-validator-errors/br-de-2-seller-contact-must-be-provided)

## Validation Tools

- [Official KoSIT Validator](https://erechnungsvalidator.service-bw.de/): Validate your XRechnung files against all BR-DE rules.
- [Convert PDF to XRechnung](/pdf-to-xrechnung): Automatic validation error fixes when converting.

## Related Resources

- [Official Specification](https://xeinkauf.de/xrechnung/)
- [Test Suite](https://github.com/itplr-kosit/xrechnung-testsuite)
- [Complete Error List](/resources/kosit-validator-errors): Overview of all German XRechnung validation rules.