On 21 November 2023, Justice Mann handed down his judgement in the English High Court in Emotional Perception AI Ltd v Comptroller-General of Patents, Designs and Trade Marks [2023] EWHC 2948 (Ch). This judgement radically altered the landscape for patenting artificial intelligence (AI) inventions in the UK, tipping the balance decisively in favour of applicants wishing to patent the use of artificial neural networks (ANNs). Following the judgement, the UK Intellectual Property Office (UKIPO) instructed its patent examiners to no longer object to inventions involving ANNs under the "program for a computer" exclusion. However, the UKIPO has now been granted leave to appeal the judgement, opening up the possibility for a further shift in the patent eligibility of AI-related inventions in the UK.

Previously, applicants wishing to patent AI-related inventions in the UK faced an uphill struggle, with such inventions often falling foul of the exclusion from patentability of computer programs "as such". Although this exclusion is not a complete bar on patentability, if a computer program is to overcome this exclusion it must provide a "technical contribution". These hurdles often proved fatal for AI-related inventions, particularly those applied to problems considered to be "non-technical", such as providing improved advertising or music recommendations based on subjective, user-based preferences.

In a radical change of approach, Justice Mann held that ANNs are not "computer programs", and therefore do not fall foul of the exclusion from patentability. Justice Mann reasoned that an ANN is not computer program because "[i]t is not implementing code given to it by a human" and is "...operating at a different level (albeit metaphorically) from the underlying software on the computer, and it is operating in the same way as the hardware ANN".

Justice Mann then went on to consider whether, in case he was wrong about ANNs not being computer programs, the invention in question provided an additional "technical contribution", which would render the ANN patent-eligible even if it were considered to be a computer program. He also found in favour of the applicant on this question, again going against established practice.

The subject of the patent application was the use of an ANN to provide improved media file recommendations to an end user, including sending a file and message in accordance with the recommendation. A typical field of use is music websites, where users may be interested in receiving music similar to another track of which they know or already have. The ANN would offer suggestions of similar music in terms of human perception and emotion irrespective of the genre of music and the apparently similar tastes of other people. The ANN is trained to discern semantic similarity (e.g. whether a piece of music is "happy", "sad", "relaxing", etc.) from the physical properties of the music track.

Justice Mann found that, despite providing media files that a user might subjectively "prefer", the ANN did make a technical contribution. He arrived at this conclusion on the basis that "a file has been identified, and then moved, because it fulfilled certain criteria", and thus "a technical thing is actually produced". He reasoned that although "those criteria are not technical criteria in the sense that they can be described in purely technical terms, they are criteria nonetheless, and the ANN has certainly gone about its analysis and selection in a technical way".

The judgement therefore represented a welcome development for those seeking to protect AI-related inventions in the UK. Where previously the UK was regarded as a difficult jurisdiction for obtaining patent protection for AI-related inventions, this new approach seemed to open the door to a far more AI-friendly approach to assessing patent eligibility. Indeed, on the back of this judgement the UKIPO suspended its guidelines for examining patent applications relating to AI inventions and released new statutory guidance for examining patent applications involving ANNs, which state that "patent examiners should not object to inventions involving ANNs under the 'program for a computer' exclusion".

The Emotional Perception AI judgement was thus seen by many to be a watershed moment for the patentability of ANNs, and AI-related inventions more generally, bringing patent eligibility more in line with wider public policy aims of promoting the UK as a hub for AI development.

However, perhaps unexpectedly given the new statutory guidance, the UKIPO has announced that it has requested and been granted leave to appeal the Emotional Perception AI judgement to the Court of Appeal.

It therefore remains to be seen whether the AI-friendly approach set out by Justice Mann in the High Court survives, or whether the Court of Appeal takes a different approach. In particular, it will be interesting to see whether the Court of Appeal agrees with Justice Mann that a computer program must be programmed by a human rather than merely comprising code, and that the "metaphorical" distinction in the way an ANN operates as compared to other software operating on a computer is also decisive.

In the meantime, the new statutory guidance for examining patent applications involving ANNs is still in force. It may therefore be worth considering parallel filings in the UK when seeking patent protection for AI-related technology in other jurisdictions. The official fees at the UKIPO are low and the current official guidance is AI-friendly, especially compared to the current approach taken by the European Patent Office, for example. Applicants should be aware though that the landscape for patenting AI-related inventions in the UK may well change yet again depending on the outcome of the appeal.

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