The interpretation of a patent is a question of law for the judge to decide, and evidence of what the patent might mean is not admissible, and nor is evidence of what the patentee had intended should be meant.
The court should look to the relevant circumstances at the time of publication.
The court may admit evidence of the meaning of technical terms.
The whole document should be read together, but if the claim is in clear language, the monopoly sought cannot be extended or cut down by reference to the rest of the specification.
The court should adopt a purposive construction.
Subsequent conduct is not available as an aid to interpretation.
A claim must not be construed with an eye on prior material in order to avoid its effect.
The patent here was not limited in the way contended by the plaintiff since there was material in the specification suggesting that particles could burn before they reached the surface.
Judges:
Staughton LJ
Citations:
[1995] RPC 255
Jurisdiction:
England and Wales
Intellectual Property
Updated: 11 May 2022; Ref: scu.656429
