Ink or pixels? The power of signatures

My father has his old habits. He only signs contracts with his fountain pen, convinced that a real signature should smell of blue ink. My sister, much to his chagrin, has just emailed him a rental contract that she signed... with a simple 'click' on her smartphone. As for my mother, who is interested in technology, she says that only an electronic signature "with a qualified certificate" would have any value. What do I say to them at the dinner table to try and get them to agree?

Mr Geneva

Under Swiss law, the classic handwritten signature, the scanned or clicked signature and the certified electronic signature can all have legal value... but not always the same value.

Under the Code of Obligations, a contract does not in principle need to be signed to be valid, unless the law expressly requires it to be in a particular form. Most contracts, including leases, can therefore be validly concluded verbally, by e-mail or even by convergent behaviour: what counts is the concordant expression of the parties' will.

That said, when a signature is required for the most binding contracts, the law imposes a "written form", i.e. a handwritten signature in the traditional sense of the term. In this respect, your father, with his good old pen, is perfectly right: there is no substitute for a handwritten signature when written form is required by law.

On the other hand, electronic signatures are now expressly recognised by the Federal Law on Electronic Signatures (SCSE). There are three types: simple, advanced and qualified. Only the qualified electronic signature - based on a recognised certificate and created using a secure device - is equivalent to a handwritten signature within the meaning of the law, and can therefore replace the latter when it is required. This is what your mother is talking about.

As for your sister's "clicked" signature, it is legally valid in many cases, particularly for contracts that do not require any special form. It expresses the intention to enter into a commitment - which is often enough - but it does not meet the legal requirements when a formal signature is required.

In short, all these signatures can be valid, but not in the same situations. The qualified signature is the only one that has the same force as a handwritten signature under Swiss law. And your father's pen is still a safe bet... as long as it doesn't run out of ink!