Comptroller - General of Patents, Designs and Trade Marks v Emotional Perception AI Limited

For Patents Act 1977, s 1(2), an artificial neural network is a computer and its weights and biases constitute a computer program, whether implemented in hardware or software. The way the weights were generated, their logical form, and their permanence are irrelevant. Applying the four-stage approach in Aerotel, the training process was subsidiary to the creation of the program. The relevant contribution was improved semantic file recommendations. Sending a file, using measurable properties, and employing technically implemented analysis did not create a technical contribution. The value of the recommendation lay in its semantic, aesthetic and subjective qualities. The application was therefore excluded from patentability.

Emotional Perception AI Ltd applied for patents concerning artificial neural networks trained to provide semantically relevant media-file recommendations. The UK Intellectual Property Office rejected the application under s 1(2) of the Patents Act 1977. Sir Anthony Mann, sitting in the High Court, allowed the appeal, holding that the exclusion did not apply or, alternatively, that the invention made a technical contribution: [2023] EWHC 2948 (Ch).

The Comptroller appealed on the meaning of computer program, the treatment of hardware and software neural networks, the mathematical-method exclusion, and the existence of a technical contribution. The central issues were whether the neural network weights constituted a computer program and whether the claimed recommendation system escaped the statutory exclusions.

Lord Justice Birss gave the leading judgment. Lord Justice Arnold and Lady Justice Nicola Davies agreed. The appeal was allowed and the Hearing Officer’s decision that the patent application was excluded from patentability was upheld.

1. Meaning of computer program. A computer is a machine which processes information. A computer program is a set of instructions causing the machine to process information in a particular way. The definition is not limited by the involvement of a human programmer, the tractability of the problem, the way the instructions were generated, their expression as logical if-then statements, or their permanence. The reasoning in Gale’s Application [1991] RPC 305 was consistent with that conclusion.
2. Artificial neural networks. An artificial neural network is a computer. Its weights and biases are instructions for that computer, irrespective of whether the network is implemented in hardware or software. The computer-program exclusion is therefore engaged. This does not itself determine patentability, since an ANN invention is in no better or worse position than any other computer-implemented invention.
3. Application of the exclusion. The four-stage Aerotel approach applied. The training process, including the pairwise comparison technique, formed part of creating the program and was subsidiary for the patentability analysis. The remaining contribution was improved file recommendations. The transmission of a file was not enough to provide a technical effect. The recommendation’s value derived from semantic similarity and its aesthetic, subjective and cognitive qualities, rather than from a technical property. The technical manner in which the ANN analysed measurable data did not alter that characterisation. The signposts did not assist.
4. Mathematical method. The court did not decide the mathematical-method exclusion. It observed obiter that the same analysis would probably have produced the same result if the ANN weights had not been treated as a computer program.

• Court of Appeal (Civil Division) allowed the Comptroller’s appeal and upheld the exclusion of the application: [2024] EWCA Civ 825.
• High Court, Chancery Division allowed Emotional Perception AI Ltd’s appeal from the UK Intellectual Property Office: [2023] EWHC 2948 (Ch).
• UK Intellectual Property Office rejected the application under s 1(2) in decision BL O/542/22.