Round-up of English Patent Litigation 2023

The year 2023 saw a further slight easing off in the level of patent trial activity in the English courts, at least in terms of determinations as to patent validity and infringement, and a reversion to the levels of 2019 and 2020. In contrast, the number of proceedings that were commenced in the Patents Court in 2023 showed an increase over 2022—45 as opposed to 35—so there is no overall sign of any slowdown.

The year 2023 saw, at first instance in inter partes proceedings in which patent infringement and/or validity was in issue, 14 final decisions in the Patents Court and one in the Intellectual Property Enterprise Court, concerning in total 22 patents. The validity of all but these patents was challenged, successfully so in respect of nine of them, with infringement being in issue in respect of all but three of the patents (including one where the patentee conceded non-infringement before trial), and as to which eight were held not to be infringed. Of the nine patents held to be invalid, six were held to be obvious, with two each anticipated by prior use, for added matter and insufficiency through lack of plausibility (some patents were invalid on multiple grounds). The patentee prevailed, in whole or in part, in relation to six patents, all of which survived challenges to validity, and all of which were held to be infringed, at a least in relation to some of the products or processes in issue, apart from one where infringement was admitted.

As shown by the following table, obviousness remained by far the most successful ground of attack on validity.

The year 2023 saw six Court of Appeal decisions in inter partes proceedings, in three of which the trial judge was reversed on validity—in two cases in favour of the patentee.¹ Although there were no decisions from the UK Supreme Court in inter partes matters in 2022, the court did give judgment on an appeal as to a decision of the UK Intellectual Property Office in relation to Artificial Intelligence (AI) inventorship as discussed below.

A summary of all the inter partes decisions on patent infringement and/or validity at first instance and on appeal in 2023 is set out in the Appendix at the end of this article.² But in addition to these final decisions on patent infringement and/or validity, there have been important decisions on substantive law and as to procedural issues as discussed below.

The highest profile, although hardly the most significant, patent decision of the year was that of the Supreme Court in Thaler.³ This was an appeal against the majority decision by the Court of Appeal, upholding the determinations by the UKIPO Hearing Officer and by the Patents Court, that an AI system could not be designated as an inventor, as the applicant in this case, Dr Thaler, had sought to do. As the court emphasized, it was only considering the narrow question as to the interpretation of sections 7 and 13 of the Patents Act 1977 and not the much wider policy questions raised by AI inventions. The court held that ‘the structure and content of [the two sections], on their own and in the context of the Act as a whole, permit only one interpretation: an inventor within the meaning of the 1977 Act must be a natural person and [the AI system in question] is not a person at all, let alone a natural person’. Although the court did not say so, one might think this to be a somewhat artificial controversy in that it would appear to have been open to the applicant, who created, owned and operated the AI system in question, to have taken a narrower view of its inventive contribution than in fact he did and to have identified himself as inventor.

Possibly one of the more significant decisions of 2023, even if only because it has provided the Court of Appeal with an opportunity to revisit the issue of excluded subject matter for the first time in many years, was an appeal from a decision of the UKIPO Hearing Officer in Emotional Perception AI Ltd’s Application.⁴ This concerned a patent application for a method that permits a type of AI system, a trained Artificial Neural Network (ANN), to align its output more closely to how a human semantically perceives content, in order to provide an improved system for recommending media files to end users. The UKIPO Hearing Officer rejected the application on the basis of the statutory exclusion from patentability for computer programs as such. On appeal to the Patents Court, Sir Anthony Mann (who has considerable experience as a Patent Court judge) reversed this decision, holding that as a matter of construction, the claim was not to a computer program and therefore the exclusion did not apply. This was because although a computer program was used at the training stage of the ANN, it was subsidiary to the claimed principle of using pairs of files for training and setting the training objective and parameters, which was one that could be implemented in either hardware (ie a physical electronic circuit) or software (ie a computer program). The ANN operated at a different level from the underlying computer software.

In the event that such conclusion was wrong, the judge went on to consider whether the claim avoided the computer program exclusion by virtue of producing a technical effect, pointing out (at [60]) that:

Drawing analogies with earlier Patents Court decisions, the judge held that an external technical effect was present because data are moved outside the computer system in the form of the file that is transferred to the user device, here disagreeing with the UKIPO Hearing Officer’s assessment that ‘[a]n effect on the end user by way of receiving a semantically similar file, such as a song they might enjoy, is not a relevant technical effect’. But the judge finally went on to conclude that in any event, ‘the trained hardware ANN is capable of being an external technical effect which prevents the exclusion applying to any prior computer program. There ought to be no difference between a hardware ANN and an emulated ANN for these purposes’.

The UKIPO has appealed the decision, but pending the outcome of this appeal, it has announced that its patent examiners should no longer object to inventions involving an ANN under the ‘program for a computer’ exclusion in the Patents Act.⁵ But even if the appeal succeeds it will be important as providing the Court of Appeal with the first opportunity for well over a decade to review the law as to the ‘computer program as such’ exclusion from patentability, where the current Court of Appeal approach, established by an earlier generation of judges, differs from that of the EPO Boards of Appeal, even if the outcomes do not necessarily differ.

Although it is rare for the Court of Appeal to reverse the trial judge in Patents Court in their assessment of obviousness, because it involves a multifactorial evaluation with which they will only interfere where there is an error of law or principle on the part of the trial judge,⁶ 2023 saw two occasions of such reversal.

In Vernacare,⁷ in which the trial judge had found the two claims in issue not to be obvious, his judgment as to one of the claims was reversed because he had, in formulating the inventive concept for the application of the established step-wise Pozzoli approach to assessing obviousness, impermissibly introduced an element which was not found in the claim. The court observed that it had been unfortunate that the judge was not referred to Hallen v Brabantia [(1991) RPC 195] because ‘[t]hat case brings home the proposition that an invention may be rendered old or obvious by a disclosure which does not articulate all the benefits of the claimed invention’. As to the other claim in issue the trial judge had failed to address the only expert evidence in the case as to such claim, which supported its obviousness, allowing the Court of Appeal to substitute its own assessment and to reverse him.

In Optis v Apple (Trial C Appeal),⁸ the majority judgment, by Arnold LJ, found that the trial judge, in finding the patents in suit to be obvious, had made an error of principle in the reliance that he had placed on the interpretation by an expert of a prior art reference, observing, at [133] (citations omitted):

However, the dissenting judgment, by Birss LJ, took a different view, in a passage which starts at [180]: