QES (qualified electronic signature)

The highest signature level under eIDAS: an advanced electronic signature created with a qualified signature creation device and based on a qualified certificate issued by an approved trust service provider. A QES has the same legal effect as a handwritten signature throughout the EU and is recognised across member states. It is only required in special cases where the law imposes formal requirements, for ordinary business agreements, an AES or SES is usually sufficient. In return, the burden of proof is effectively reversed: with a QES, the party disputing the signature must prove it is not genuine.