Art. 117(1) EPC does not contain an exhaustive list of admissible evidence, only mere examples. Parties to the proceedings are thus free in their choice of evidence. Any kind of evidence is admissible during proceedings before the EPO.

Before an administrative authority or a court takes a decision, it is required to establish the existence of the material facts, i.e. the facts from which, under the relevant legal provision, the legal effect ensues. The facts are established by taking evidence. The purpose of all evidence, whatever its nature, is to confirm a party's assertions.