Claims shall be supported by description (Section 25(5)(c))

Features defined by function

5.104 Claims will often define one or more elements of a claim in terms of what it does rather than what it is. The monopoly includes any elements that will achieve this desired result, e.g. “fastening means”, “braking means”. The following claim was found to acceptable in Lightening Fastener v Colonial Fastener [1934] 51 RPC 349:

“A machine for making fasteners having means for feeding a tape step by step, means for feeding fastener members into position to be compressed on to said tape, and means for compressing the fastener members thereon.”

5.105 Claims may also define a desired result from the combination of one or more features, often indicated by a “whereby” clause, in which, after the claimed elements are set out, the result flowing from the use of these elements is defined, for example “… whereby the fluid passes from the first tank to the second tank.”

5.106 Claims may broadly define features in terms of their function, even where only one example of the particular feature has been given in the description, provided the skilled person would appreciate that other means could be used for the same function. However, if on a reading of the application it appears that the function must be performed in a specific manner, then the claim may lack support (American Home Products Corp v Novartis Pharmaceuticals UK Ltd [2001] RPC 8 at [39] [43]). In this regard, vague references or general statements in the specification may not be sufficient, particularly if it is not reasonably clear what the alternatives might be or how they might be used.

5.107 Since functional claims are generally broader than claims reciting structural elements, the Examiner should be certain that the claims are neither ambiguous nor unduly broad. The judgment should be made as to the technical contribution made by the invention, and whether the claim goes beyond that contribution.