1. When an essential ingredient comprised in a chemical composition is open to be labelled arbitrarily "active ingredient" or not depending exclusively on the mental label the user wishes to apply, thereby rendering the meaning of that feature protean, then the public is left in doubts as to the distinction which compositions are covered by the claim and which are not, which is at variance with the principle of legal certainty. Because of that lack of legal certainty, the claim fails to meet the requirement of clarity imposed by Article 84 EPC. (reasons point 4.1.2.2)

2. The absence from the independent claim of any upper limit on the amount of a particular component in the chemical composition claimed, is at variance with the aim of the invention as set out in the description; hence that claim is so broad that it goes beyond the scope of the invention as disclosed in the description. Therefore, the requirement of Article 84, second sentence, EPC, that the claims must be supported by the description is not meet. (reasons point 4.2)