Patent Infringement in UK Law

Conversely the English court could not entertain a claim for the infringement of a German patent. English patent law as embodied in the Patents Act 1977 is founded on international convention, not just European Community convention, but, subject to certain special provisions of the Act, its application by the English court is a matter of English law.

If I may summarise the effect of these two well-known statements, the matter relied upon as prior art must disclose subject-matter which, if performed, would necessarily result in an infringement of the patent. That may be because the prior art discloses the same invention. In that case there will be no question that performance of the earlier invention would infringe and usually it will be apparent to someone who is aware of both the prior art and the patent that it will do so.

Secondly, the fact that the language of the claim does not on any sensible reading cover the variant is certainly not enough to justify holding that the patentee does not satisfy the third question. Thirdly, when considering the third question, it is appropriate to ask whether the component at issue is an "essential" part of the invention, but that is not the same thing as asking if it is an "essential" part of the overall product or process of which the inventive concept is part.

A decision of an English court declaring a patent invalid, or (which will normally follow) revoking it, will have effect in the United Kingdom only, whereas a corresponding decision of the EPO, which was the authority by which the patent was granted, will have effect in all the states for which the patent was granted.

Fourthly, the possibility of the duplication of proceedings contesting the validity of a patent granted by the EPO is inherent in the system established by the EPC. In practice national courts exercise exclusive jurisdiction on infringement issues and they have concurrent jurisdiction with the EPO on validity issues.

My Lords, a patent specification is a unilateral statement by the patentee, in words of his own choosing, addressed to those likely to have a practical interest in the subject matter of his invention (i.e. "skilled in the art"), by which he informs them what he claims to be the essential features of the new product or process for which the letters patent grant him a monopoly.

Now it is true that in an inquiry as to damages or account of profits the patentee is allowed to claim relief for types of alleged infringement not ruled on by the trial court. This saves the formal issuance of fresh proceedings in respect of these and is permitted as a matter of convenience, see General Tire v Firestone [1975] RPC 203 at p.207).