2.4.5.2.3 Use of Common General Knowledge

Date Published

It is legitimate to read a citation in the light of common general knowledge.  Thus:

"a given specification is not to be read in a vacuum. The reader must be regarded as having at least the common knowledge of the art."

Acme Bedstead v Newlands (1937) 58 CLR 689 at page 704.

Following from 2.4.5.2.2 Date for Construing Citation, the relevant common general knowledge is that known at the date of publication of the citation. (In contrast, for an objection of lack of inventive step, the relevant common general knowledge is that known at the priority date of the claim in question).

Common general knowledge is that knowledge which every worker in the art may be expected to have as part of his or her technical equipment (Automatic Coil Winder Co Ld v Taylor Electrical Instruments Ld (1944) 61 RPC 41 at page 43). It is compounded of training, experience, observation and reading. While in a court situation the common general knowledge may be established by the direct evidence of a person skilled in the art, such advice is usually unavailable during examination.

Consequently, while in general examiners are not persons skilled in the art, during examination their knowledge of common general knowledge, can, in the first instance, be relied upon, when determining novelty or inventive step (see also 2.5.2.6 Evidentiary Requirements).

Note, however, that when responding at further report stage, depending on the evidence and argument supplied by the applicant, it may be appropriate to support further arguments on the nature of the common general knowledge, by reference to written material.

Reading "in the light of common general knowledge" is a process whereby the words and phrases used in a document are given the meaning that they would have had to a person skilled in the art at the relevant date. For example, "adhesive means" would be read in the light of the common general knowledge to be a reference to any adhesive that the person skilled in the art would have understood as appropriate.

This is not a process of using the common general knowledge to read mechanical, chemical, or other technical features into the citation which are not implicitly present. That process is one of adding common general knowledge.  Examiners must not add common general knowledge to a citation to establish lack of novelty.

"It is contended, however, that there is no justification for, to put it shortly, adding common general knowledge to an alleged paper anticipation and thus depriving a patent of subject matter."

Acme Bedstead v Newlands supra.

Further information on common general knowledge is provided in 2.5.2.1 Common General Knowledge.