A further special case is where the invention is characterised by parameters. Provided that the conditions for defining the invention in this way are met (see F‑IV, 4.11), the definition of the invention must should appear completely in the claim itself whenever this is reasonably practicable. In principle the method of measurement is necessary for the unambiguous definition of the parameter. The method of and means for measurement of the parameter values need not however be in the claims when:
However, in all other cases the method of and means for measurement should must be included in the claims as the claims define the matter for which protection is sought (Art. 84).