T 0482/89 (Power supply unit) of 11.12.1990

I. Under Article 117(1)(c) EPC, in any proceedings before, inter alia, an Opposition Division or a Board of Appeal, the means of giving or of taking evidence may include the production of documents. As the EPC neither defines the term "documents" nor gives any indication of the probative value of such documents, the principle of free evaluation of evidence applies. Any kind of document therefore, regardless of its nature, is admissible during proceedings, including appeal proceedings, before the European Patent Office. The probative value of any such document, however, depends on the peculiar circumstances of the particular case.

II. The principle of free evaluation of evidence also applies to the hearing of witnesses under Article 117(1)(d) EPC. In particular, the EPC does not rule out hearing an employee of one of the parties to the proceedings as a witness.

III. It is a principle well-established in the case law of the majority of Contracting States that a single sale is sufficient to render the article sold available to the public within the meaning of Article 54(2) EPC, provided the buyer is not bound by an obligation to maintain secrecy. It is not necessary to prove that others also had knowledge of the relevant article.