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

Factual and Procedural Background

This appeal concerned whether a patent could be granted for a file-recommendation system/method using an artificial neural network (“ANN”). The claimed approach trained an ANN on pairs of media files by aligning (i) “semantic” separation distances derived from natural-language processing of human descriptions with (ii) separation distances derived from objectively measurable physical properties of the files. After training, the ANN generated vectors from physical properties alone, enabling recommendations intended to elicit similar human emotional responses.

Company A (the Appellant) applied for a patent but was refused by a Hearing Officer at the UK Intellectual Property Office (“UKIPO”) on the basis that the claims were excluded as “programs for computers … as such” under the Patents Act 1977, reflecting article 52(2)(c) and (3) of the European Patent Convention (“EPC”). The High Court allowed Company A’s appeal and held that an ANN was not a computer program and that the exclusion did not apply: [2023] EWHC 2948. The Court of Appeal allowed the Respondent’s appeal and restored the refusal: [2024] EWCA Civ 825. Company A appealed to the Supreme Court.

Legal Issues Presented

1. Whether the four-step approach in Aerotel for applying article 52 EPC (and the Patents Act 1977) should no longer be followed in light of the EPO Enlarged Board decision in G1/19.
2. Whether an ANN is (or contains) a “program for a computer” within article 52(2)(c) EPC.
3. If the computer-program exclusion is engaged, whether the claims are nevertheless not excluded because they are not for a “program for a computer … as such” (article 52(3) EPC), including the role of the “any hardware” threshold and the EPO’s “intermediate step” filter before assessing novelty and inventive step.

Arguments of the Parties

Appellant's Arguments

• ANNs are not “programs for computers” because (as framed by Company A) a “hardware ANN” lacks a CPU executing a sequence of logical instructions, and therefore does not have a “program”; the same should apply to “emulated” (software-implemented) ANNs because they are functionally equivalent.
• The relevant exclusion should not apply to the claims on a proper understanding of what counts as a computer and a computer program.

Respondent's Arguments

• Aerotel should continue to be applied in the UK notwithstanding G1/19, including on the basis that changing methodology would be disruptive and might not change outcomes.
• An ANN (however implemented) is a programmable computer and has a “program,” constituted by the weights and biases (adjustable parameters) that determine how information is processed.

Interveners' Arguments

• The Court of Appeal’s definition of a computer as “a machine which processes information” was said to be overbroad.
• An ANN was characterised as an abstract computational model/function mapping inputs to outputs, not itself a computer; and its weights and biases were argued to be data used by the model rather than a computer program.

Table of Precedents Cited

Court's Reasoning and Analysis

• Interpretation of EPC article 52 / replacing Aerotel (Issue 1): The Court held that, given section 130(7) of the Patents Act 1977 and the strong policy of uniform EPC interpretation, UK law should adopt the Enlarged Board’s interpretation in G1/19. The Court considered that Aerotel was rejected by the Enlarged Board on the basis that it misinterpreted “invention” by focusing on “contribution” and thereby mixing eligibility under article 52 with novelty and inventive step. The Court retained step 1 of Aerotel (proper claim construction) but rejected steps 2–4, and endorsed using the Duns principles (excluding principle (G)) together with G1/19’s “intermediate step” filter for mixed technical/non-technical features.
• Inventive step methodology: Aligning with G1/19 did not, in the Court’s view, require the UK to adopt the EPO’s problem-and-solution method as a matter of law. The EPC (article 56) was treated as not prescribing a single methodology, and Pozzoli (as approved in Actavis v ICOS) remained legitimate.
• Whether an ANN is a “program for a computer” (Issue 2): The Court rejected an unduly narrow definition tying “computer” and “program” to conventional CPU-based digital computers, reasoning that the EPC must accommodate technological change. It characterised an ANN as an abstract model capable of being implemented on various hardware (including conventional computers and dedicated hardware), and held that the machine implementing it functions as a computer by performing computations on data. The ANN—considered as topology, activation functions, and weights/biases—amounts to a set of instructions that causes data to be processed in a particular way, and therefore is a “program for a computer.” The fact that parameters are learned, may be parallelised, or may be fixed in hardware after training did not alter that conclusion.
• “As such” and technical character (Issue 3): Applying G1/19’s “any hardware” eligibility threshold, the Court held it was beyond dispute that the claims had technical character and were not excluded as a computer program “as such.” The method necessarily involved computer hardware to implement the ANN and also referred to hardware elements (database, communications network, user device). Therefore, the UKIPO’s refusal under article 52 was wrong. The Court explained the EPO “intermediate step” as a necessary filter before assessing novelty/inventive step, but declined to apply it to the present claims due to the way the case had been argued below (through the Aerotel lens) and the absence of detailed submissions on how to conduct that filtering exercise for these claims.
• Disposition and remit: Because novelty and inventive step had not yet been assessed by the UKIPO, and because the intermediate-step analysis was not properly developed on the appeal, the Court confined itself to resolving the article 52 issues and remitted the remaining assessment to the Hearing Officer.

Holding and Implications

ALLOWED: The appeal was allowed and the Hearing Officer’s refusal was set aside.

The Court held that the UK should no longer follow the Aerotel methodology (save for claim construction) and should align with the EPO Enlarged Board’s interpretation in G1/19. Although an ANN was held to be a “program for a computer,” the claims were not excluded as a computer program “as such” because they had technical character under the “any hardware” approach. The application was therefore returned to the UKIPO for consideration of novelty and inventive step; the Supreme Court did not determine those questions and did not apply the full “intermediate step” filtering exercise to the specific claims on the record before it.