SDI WS - B2B invoices

Hello,

Sorry I don’t speak Italian.
We want to act as an intermediary doing B2B e invoicing for our customers in Italy.
We ask for some help, a lot of documentation is in Italian.

For SDI fatturapa, e-invoices and notifications xml must be signed (or at least our customer require that we sign them) with a qualified signature with a certificate. The regulation seems to be that this certificate must be owned by the issuer of the invoice. In our case it is our customer the issuer of the invoice, we will only pass it to SDI.
1 . Is it possible to nevertheless sign the certificate with a certificate issued to us? Because we are an intermediary and it would make sense if we could sign our customers invoices with our own certificate.
2 . If not, it means that in the future if we provide our intermediary service to 10 customers, we must sign e-invoices of each customer with a separate certificates (the one of the customer)?

For the e-invoices/notification conservation at Italy is necessary to respect a legal procedure.
We also want to provide this service to our customer beside sending invoices to SDI.
But we don’t understand the details of the procedure and how to do it.
3 . Can someone explain this procedure , what is required ? what is “the document of conservation” ?
4 . Is this link https://www.agid.gov.it/en/platforms/storage the good link to know how to archive file invoices ?
It says

Citazione Public and private entities that carry out activities for the storage of electronic documents and which intend to become accredited must submit the accreditation application to the Agency for Digital Italy.

5 . Is it the case and we need to submit the accreditation application to the Agency for Digital Italy ?

Thanks for your help.
Best regards
Aymeric

You can sign invoices with the intermediary certificate. If you need to sign programmatically, you may use the certificate issued by Agenzia delle Entrate for Entratel or SDIFTP services.

To archive invoices and notifications for your private customers, you don’t need to submit any accreditation application.