T 0923/92 (human t-PA) du 08.11.1995

I. The skilled person considers a reference to a particular amino acid sequence in a claim as a true technical feature characterizing the invention. Such a claim is not under Article 87 entitled to priority from an earlier application in which that amino acid sequence was not disclosed (cf. points 8 and 16 of the Reasons).

II. A claim to a process which comprises the preparation of a protein which has human tissue plasminogen activator (t- PA) function, without further indication which of the many functions of human t-PA are meant, is not allowable under Articles 83 and 84 EPC. This is firstly because the skilled addressee would be left guessing whether or not a derivative which fulfils only one of the functions typical of this molecule falls under the scope of the claim. Moreover, the requirement of Article 83 EPC is not fulfilled if the claim, on the basis of the broadest possible meaning of the functional definition contained in it, relates to an invention which, having regard to the examples and the information given in the patent specification, cannot be performed in the whole area claimed by a person skilled in the art, using common general knowledge, without undue burden (cf. point 27 of the Reasons).

III. Given a description that contains adequate information how to produce human t-PA, and a claim directed to derivatives of human t-PA with an indication of the functions to test for, the skilled person can be expected to be able to prepare without application of inventive skill or undue burden, derivatives of human t-PA by way of amino acid deletion, substitution, insertion, addition or replacement and test which of the derivatives satisfy the functional requirements, so that the claimed invention is adequately described for the purpose of Article 83 EPC [cf. points 44 and 45 of the Reasons].