T 0337/95 (Lower alkyl) of 30.01.1996

1. Claims have to be clear for the sake of legal certainty (Nos. 2.2 to 2.4). 2. Since, in the absence of any unambiguous reference point, a relative term such as "lower alkyl" in the field of organic chemistry does not have a generally accepted meaning with respect to its maximum number of carbon atoms, such a term is ambiguous and therefore not suitable for clearly defining the subject-matter for which protection is sought in a claim which is directed to a group of organic compounds per se (No. 2.8).