Concept Definition
What is a digital signature?
A digital signature is a cryptographic mechanism that uses asymmetric key cryptography to authenticate the identity of the signer and verify that a signed document has not been altered since signing. In e-invoicing, digital signatures provide non-repudiation and integrity for invoice documents.
What types of digital signatures exist for invoicing?
The eIDAS Regulation defines three levels of electronic signatures relevant to invoicing:
- Simple Electronic Signature (SES): Any electronic data associated with a signer. Not legally recognized for invoicing.
- Advanced Electronic Signature (AES): Uses a certificate linked to the signer. Changes are detectable. Widely used in e-invoicing.
- Qualified Electronic Signature (QES): AES created with a Qualified Electronic Signature Creation Device (QESCD). Legally equivalent to a handwritten signature across the EU.
Frequently Asked Questions
- Is a digital signature required on EU invoices?
- No. EU VAT rules (Article 233 of the VAT Directive) permit businesses to use any business control method that establishes a reliable audit trail between an invoice and a supply. Digital signatures are one acceptable method alongside EDI, qualified audit trails, and other integrity controls.
- What is an electronic seal?
- An electronic seal is similar to a digital signature but is associated with a legal entity rather than an individual. Under eIDAS, a Qualified Electronic Seal provides the same legal recognition as a Qualified Electronic Signature for organizational documents.