SIGN ES - How does invoicing by recipient work?

Invoicing by recipient is supported in Spain through the SIGN ES API, but only for transactions that fall under the VERI*FACTU system. 

This functionality is not available in regions covered by the TicketBAI system, which includes the Basque provinces of Álava, Bizkaia, and Gipuzkoa.

When creating an invoice of type COMPLETE, or when submitting any related corrections, you must include the issued_by block.

This block consists of two pieces of information:

• type (required): This must be set to RECIPIENT. When selected, the Verifactu XML is generated according to the legal and technical requirements for recipient-issued invoices.
• invoicing_agreement(optional): If there is a formal agreement between the supplier and the recipient, you may include its registration number in this field.

Important: In this scenario, the recipient indicated in the invoice is the taxpayer who is legally required to issue the invoice. This means the customer is responsible for the invoice—not the supplier.