Interpretation of Citations - Inherency

Date Published

For further information regarding Novelty see Ch 12 of the PCT GL, for Inventive Step see Ch 13 of the PCT GL and in particular for inherency see 12.04 of the PCT GL.

For a citation to anticipate the claims it must disclose every element or step of the invention, explicitly or inherently to the person skilled in the art. Where a feature is not explicitly disclosed, the citation must be interpreted to ascertain if the feature is implicitly or inherently disclosed.

An inherent or implicit disclosure can occur because the missing feature is something that is readily apparent to the person skilled in the art and they would read that information as being implicit. In this case, no documentary evidence would be required to support the feature being inherent because there is no question as to it being otherwise. Alternatively, the missing feature can also be implicit in the sense that when the teaching of the prior art is carried out, the inevitable result of that teaching falls within the scope of the claims. This can occur when the missing feature is a property of a particular substance, the property existing due to the nature or structure of the substance and cannot be removed from the substance (see example 2 below).

In establishing a lack of novelty involving inherency, the inherent or implicit feature may not be established by probabilities or possibilities. The feature must inevitably result from the teaching of the document. Where the result is uncertain, or requires justification, the citation should be considered for inventive step rather than novelty. Similarly, well-known equivalents not disclosed in the prior art are not implicit or inherent but should be considered in relation to inventive step.

Example 1:

Where the elastic properties of rubber are relied upon in a document that does not explicitly state that rubber is an “elastic material,” a claim to an “elastic material” is anticipated because the rubber taught in the prior art inherently is an “elastic material”.  

Example 2:

The claim is to “An anti-cancer aspirin.”, while the citation discloses aspirin that may be used for pain relief but does not disclose aspirin’s anti-cancer activity.  

The claim is interpreted as being to the compound aspirin per se, wherein the compound has a particular property (anti-cancer). The new property does not change the chemical compound, rather, the new property is inherent in the compound because of the compound’s physiochemical attributes. The compound, with this property, existed prior to the discovery of the property and therefore the property is inherent to the compound. Claims to the compound per se would not be novel because any person in preparing aspirin from the citation would inevitably produce the compound with the new (but unknown) property. However, claims to a method for treating cancer using aspirin would be novel.