# VF-1155

Source: https://xmlvalid.com/rules/VF-1155

> Se está informando el bloque Tercero sin estar informado el campo EmitidaPorTerceroODestinatario.

- Level: error
- Rule sets: VERI*FACTU checks of the AEAT Validaciones 1.2.2 (8 April 2026)
- Context: `/*:RegFactuSistemaFacturacion/*:RegistroFactura/*:RegistroAlta`
- Test: `not(*:Tercero) or $by != ''`

In English: The Tercero block is given but EmitidaPorTerceroODestinatario is not.

Validate a document against these rules: https://xmlvalid.com/validate