How to write claims?
Obtaining a patent in France: the patent application

Claims define the object of the protection sought by indicating the technical features of the invention. Unless absolutely necessary, claims may not be based on mere references to the description or drawings in order to express the technical characteristics of the invention. They must be clear and concise, and based on the description (article L. 612-6 of Code de la propriété intellectuelle (CPI) ).

Unless justified by the nature of the invention, all claims must include (article R. 612-17 of the CPI):

• a preamble mentioning the designation of the object of the invention and the technical features which are necessary to define the claimed elements but which, in combination, form...