“[107] Mr Wyand submitted that the court should be slow to arrive at a construction which resulted in a finding of invalidity for obviousness over common general knowledge. He relied on a passage in Terrell on the Law of Patents, 17th Edition at paragraph 9-107: ‘The overall principle is therefore that a construction which leads to a foolish result should, if possible, be rejected as being without the intention of the patentee, for a construction which does not lead to an absurd result is to be preferred. However a finding of invalidity cannot of itself be regarded as an absurd result, unless the relevant piece of prior art is specifically acknowledged in the patent, or unless the invention would to the knowledge of the ordinary reader then be obvious simply in the light of common general knowledge.’ [108] This passage follows a discussion of two cases. The first is a decision of this court in Ocli Coating Laboratory v Pilkington[1995] RPC 145 . In that case the court concluded that a good reason for confining the meaning of the claims to what it described as a literal construction was that, if the wider construction was adopted, the patent would be rendered obvious in the light of the prior art. As the authors of Terrell point out, however, that cannot be a universal proposition. Where there is no reason to assume that the patentee was aware of a particular piece of prior art, his claim may well have been framed in ignorance of it. In such circumstances it would be wrong to impute to the patentee an intention to frame a claim so as to avoid attacks which could be based on it. It is also perhaps relevant to observe that that case was decided at a time when the courts decided construction by making a distinction between the strict, literal or acontextual meaning of the language and its purposive meaning, as opposed to adopting the unitary approach propounded in Kirin Amgen. One aspect of that approach invited speculation as to whether there was a possible reason why the patentee might have wanted to restrict himself to the strict, literal meaning. [109] The second case cited was a decision of Jacob J in Beloit v Valmet (No 2)[1995] RPC 705 . At page 720 Jacob J pointed out: “… there is normally no reason to suppose the patentee when he set the limits of his monopoly knew of a particular piece of prior art … Of course the position is different if the prior art is specifically acknowledged in the patent…” [110] Even if prior art is specifically acknowledged, much may turn, as Lewison J pointed out in Ultraframe v Eurocell[2005] RPC 7 at[73], on the way in which the prior art is referred to in the patent. [111] As with any canon of construction, one must be wary of treating it as a rigid rule. Moreover as soon as one departs from documents specifically acknowledged in the specification, the skilled reader has no basis for assuming that the patentee was aware of the document in question. Still further, where the objection is one of obviousness rather than lack of novelty, a value judgment is involved on which widely differing views are possible. It is true that if the document is said to form part of the common general knowledge, it might be said to be more likely that the patentee is aware of it. But a patentee may have been isolated from the common general knowledge, or may, despite the later finding of obviousness, have genuinely believed that he had made an invention over it. As will be seen below, the argument of invalidity over Kerpez involved, amongst other things, resolving a dispute between experts as to the feasibility of identifying noise sources. I am not persuaded therefore that it would be right to give weight to this factor in the present case.” ‘The overall principle is therefore that a construction which leads to a foolish result should, if possible, be rejected as being without the intention of the patentee, for a construction which does not lead to an absurd result is to be preferred. However a finding of invalidity cannot of itself be regarded as an absurd result, unless the relevant piece of prior art is specifically acknowledged in the patent, or unless the invention would to the knowledge of the ordinary reader then be obvious simply in the light of common general knowledge.’ “… there is normally no reason to suppose the patentee when he set the limits of his monopoly knew of a particular piece of prior art … Of course the position is different if the prior art is specifically acknowledged in the patent…”
“73. The document continues to describe a further aspect where the base unit is provided with detachable modules which carry at least one group of signal outputs. This continues the same idea in that the skilled person would understand that the design and circuitry of the base unit, instead of including the output circuitry, would have an additional receptor for inserting groups of signal outputs each linked (by the circuitry in the base unit) to one of the directional couplers. 74. Again, this is different from the prior art described in the Background to the Invention in that instead of having modular combined directional couplersplitters, in the second ‘aspect’ [of the invention] the directional couplers and splitter units are individually modular and the base unit has two kinds of receptors, one for directional couplers and one for splitter units. It is also different from the method of attaching components to the back board of the cabinet and wiring them together in that it provides a unit which can be plugged into the network and which contains circuitry and convenient receptors into which components can be inserted.”
“…the directional coupler means is separable from and insertable into the base unit independent of the group of signal outputs.”
“As the directional coupler is separable from and insertable into the base unit independent of the group of signal outputs, the signal levels of the outputs can be selected as required by an engineer according to need, and as the directional couplers are relatively small and inexpensive components, this ensures that the value and volume of items that an engineer needs to carry with him to provide the necessary variations in signal output required is substantially reduced.”
“There are clearly benefits to the Patented approach of being able to remove the directional couplers without physically affecting any of the signal outputs.”
“Ever since the power of the Crown to grant monopolies was curbed by parliament and the courts at the beginning of the seventeenth century, it has been a fundamental principle of United Kingdom patent law that the Crown could not grant a patent which would enable the patentee to stop another trader from doing what had been done before.”
“It is impossible for an ordinary member of the public to keep watch on all the numerous patents which are taken out and to ascertain the validity and scope of their claims. But he is entitled to feel secure if he knows that that which he is doing differs from that which has been done of old only in non-patentable variations …”
“[56] It is, we would accept, still not the practice to adopt Lord Moulton's approach to deciding conventional patent actions where both validity and infringement are in issue. The court will resolve those issues individually by reference to the claims of the patent, rather than take the short cut of deciding whether the defendant's product is old or obvious. That is because, as we think Lord Moulton was recognising, the validity of a granted patent involves more 90. than just the private interests of the parties. If the patent is indeed to be impaled on the validity horn of Lord Moulton's dilemma, then it is in the public interest that it be decided and the patent revoked. That same policy is visible in Traction Corporation v Bennett (cited above). That consideration does not, however, detract from the potential usefulness of the principle that Lord Moulton was espousing. In a conventional patent action a determination that there is nothing new or inventive about the defendant's product may operate as a cross-check on the outcome of the action as a whole.”
“[163] Counsel for the defendants submitted that it was no longer the law that a claim lacked novelty if the prior publication disclosed subject-matter which, if performed, would necessarily infringe the claim. Rather, the claim would only lack novelty if the prior publication disclosed subject-matter which fell within the claim on its proper interpretation. It was not sufficient that the subjectmatter would infringe the claim applying the doctrine of equivalents. … [167] The conclusion I have reached is that counsel for the defendants is correct.” [167] The conclusion I have reached is that counsel for the defendants is correct.”
“… [A] determination of infringement based on [the doctrine of equivalents] cannot be made in a vacuum; the prior art must be examined to assure that the range of equivalents asserted by the patent holder does not encroach upon subject-matter in the prior art… This, of course, involves consideration of what the prior art would have anticipated…and what the prior art would have made obvious…when the patentee filed the original application. In this way, the doctrine of equivalents is limited; it may not be used to extend a patent holder’s right to exclude beyond what could lawfully have been obtained in an original application.”
“A doctrine of equivalents theory cannot be asserted if it will encompass or ‘ensnare’ the prior art. [References given]. A ‘[h]ypothetical claim analysis is a practical method to determine whether an equivalent would impermissibly ensnare the prior art.’ We have explained: Hypothetical claim analysis is a two-step process. The first step is ‘to construct a hypothetical claim that literally covers the accused device.’ Next, prior art introduced by the accused infringer is assessed to ‘determine whether the patentee has carried its burden of persuading the court that the hypothetical claim is patentable over the prior art.’ In short [the court] ask[s] if a hypothetical claim can be crafted, which contains both the literal claim scope and the accused device, without ensnaring the prior art.”
“Having a tap with an electrical base unit into which the trunk cable is plugged, the base unit also carrying the signal to receptors into which modular directional couplers can be inserted (and potentially with other receptors for splitter units).”
“During the period23 May 2006 to19 December 2016 the Second Claimant was the sole legal entity with the authority of the proprietor of the Patent to manufacture products falling within the scope of the claims of the Patent in the jurisdiction. In the premises the Claimants contend that the Second Claimant was the exclusive licensee of the Patent under an implied licence.”