Selection Specification Must Describe Advantage

Date Published

The specification must describe the advantage possessed by the selected members and upon which the selection is based.

"A mere selection among possible alternatives is not subject matter. A selection to be patentable must be a selection in order to secure some advantage or avoid some disadvantage. It must be an adaptation of means to ends impossible without exercise of the inventive faculty. It follows that in describing and ascertaining the nature of an invention consisting in the selection between possible alternatives, the advantages to be gained, or the disadvantages to be avoided, ought to be referred to.”

Clyde Nail Company Ltd v Russell (1916) 33 RPC 291 at page 306.  

Similar views were expressed in the case of I.G. Farbenindustrie A.G.'s Patents (1930) 47 RPC 289 at page 323:

"I must add a word on the subject of the drafting of the specification of such a patent. It should be obvious, after what I have said as to the essence of the inventive step, that it is necessary for the patentee to define in clear terms the nature of the characteristic which he alleges to be possessed by the selection for which he claims a monopoly. He has in truth disclosed no invention whatever if he merely says that the selected group possesses advantages. Apart altogether from the questions of what is called sufficiency, he must disclose an invention; he fails to do this in the case of a selection for special characteristics, if he does not adequately define them."

Although specifications which are drafted in the first instance as a selection will usually have a clear statement of the advantages of the selection, this may not be the case where the draftsperson drafted the specification without knowledge of the parent class. This is particularly likely where a "whole of contents" objection is being considered. In certain circumstances, an amendment of the specification to describe the advantages may not be allowable under sec 102 (see The Section 102(1) Provisions Explained, Meaning of “claim or disclose matter that extends beyond"). See also Ethyl Corporation (Cook's) Patent [1970] RPC 227.