T 0081/87 (Preprorennin) of 24.01.1989

In accordance with Article 87(1) EPC a European patent application is only entitled to priority in respect of the same invention as was disclosed in the previous application. This means that the subject-matter of the claims of the European application must be clearly identifiable in the previous application as a whole. Identical wording is not required. In order to give rise to priority the disclosure of all the essential elements, i.e. features of the invention in the priority document must either be express, or be directly and unambiguously implied by the text as filed. Missing elements which are to be recognised as essential only later on, are thus not part of the disclosure.