4.2.1Disclosing your invention 

4.2.001The European patent application must disclose the invention in a manner sufficiently clear and complete for it to be carried out by a person skilled in the art. 

The description and any accompanying drawings form the basis for the claims, which determine the extent of the protection conferred by the European patent. The description and the drawings are also used to interpret the claims. 

4.2.002Once a European patent application has been filed, no amendments extending beyond its content as filed may be made to the description, the claims or the drawings. Hence you are not allowed to add examples or features to the application documents at a later date to remedy deficiencies in the disclosure. Nor are you allowed to extend the subject-matter of the claims, e.g. by omitting certain features, unless there is clear support for such amendment in the application as filed. You must therefore make sure that the claims as filed clearly and accurately identify the invention that you want to protect (see also point 5.4.021).