Legality and enforceability of electronic signatures in Switzerland*

Switzerland legalized electronic signatures in 2017 with the Federal Act on Electronic Signatures, ZertES Act. Before that, all documents had to be signed with traditional signatures.

ZertES and the Swiss Code of Obligations provide the legal framework for the use of electronic signatures. While inspired by the EU's eIDAS, ZertES has some unique provisions.

ZertES defines an electronic signature as any data in electronic form that is attached to other electronic data or logically linked to it and serves to authenticate it. Simple electronic signatures, such as scanned signatures or those made on the terminal of a postman, are usually used to verify the integrity of a document. But besides this, ZertES defines several other types of electronic signatures:

• Advanced electronic signature.
• Regulated electronic signature.
• Qualified electronic signature.

ZertES explicitly defines the requirements for advanced electronic signature:

• The signature must be assigned exclusively to the holder.
• It allows one to identify the signer.
• The signature is produced by means that the signer can keep under their sole control.
• The signature is linked to the signed document in such a way that subsequent changes to the document can be detected.

A regulated electronic signature is a type of advanced electronic signature created using a secure signature creation device and cryptographic keys. It is based on a regulated certificate issued to a natural person and valid at the time the electronic signature was created.

The law requires that the cryptographic keys must be:

• Unrepeatable and sufficiently confidential.
• Protected against forgery by necessary technological measures.
• Reliably protected by the legitimate owner against misuse by others.

In Switzerland, a qualified electronic signature is a legal equivalent to a handwritten signature and must be based on a qualified certificate, which can only be issued by licensed service providers. This signature can only be issued to an individual. Its certificate is similar to that of a regulated electronic signature but with three key differences:

1. It must specify that it is solely for electronic signatures.
2. It must include a reference indicating that it is a qualified certificate.
3. It must be issued by an issuing certified organization.

According to Swiss procedural laws, courts have the discretion to evaluate evidence as they see fit, with no legal preference for specific types of evidence. This means any type of electronic signature cannot be rejected as evidence simply because it is in electronic form.

However, if other types of electronic signatures were used, the signer must prove that the document's integrity has been maintained. While simple, advanced, and regular electronic signatures are not excluded as valid evidence, they may not hold the same legal weight as a handwritten signature. In Switzerland, only a qualified electronic signature with an authenticated stamp is considered equivalent to a handwritten signature.

In Switzerland, a person is prohibited to use an electronic signature when executing the following documents:

• Consumer-related documents relating to tenancy and employment law for apprenticeships.
• Entire documents that must be written by hand, such as a contract of surety or holographic wills.
• Documents requiring notarization or public certification, e.g., marriage and inheritance contracts, real estate transactions, establishment of legal entities, etc.

Last updated: September 2024