According to Article 123(2) EPC, a European patent application or a European patent may not be amended in such a way that it contains subject-matter which extends beyond the content of the application as filed. A claim, the wording of which is essentially identical to a claim as originally filed, can nevertheless contravene the requirements of Article 123(2) EPC, if it contains a feature whose definition has been amended in the description in a non-allowable way. The specific definition of a feature, which according to the description is an overriding requirement of the claimed invention, is applied by a skilled reader to interpret this feature whenever it is mentioned in the patent (see points (11) to (15) of the Reasons for the Decision).