What does the "Signed PDF" e-invoicing mode mean?

The "Signed PDF" mode is one of the invoice processing modes in tax e-invoicing recognised under regulations.

E-invoices in "signed mode" are secured with an electronic signature in compliance with the tax regulations in force, affixed by CEGEDIM on the supplier's behalf. E-invoices in "signed mode" are accompanied by the electronic signature and associated certificate and archived for ten years in an electronic safe dedicated to the supplier.

For example, French regulations require an electronic signature based on a qualified electronic certificate issued by a certification service provider or an electronic signature accepted by the tax authority as equivalent to a qualified signature, namely a signature that complies with the general security repository (RGS) at the 2- or 3-star level

For France invoice flows, CEGEDIM uses a 2-star RGS signature based on a qualified CERTINOMIS certificate.