In Brief
The UK Supreme Court has delivered its long-awaited ruling in Emotional Perception AI Limited v Comptroller General of Patents, Designs and Trade Marks, a decision that significantly alters how patent applications involving artificial intelligence, artificial neural networks (ANNs), and computer-implemented inventions are assessed in the United Kingdom.
A major outcome of the ruling is the removal of the long-standing Aerotel test, which had been used to evaluate patent eligibility. It has now been replaced by the “any hardware” approach, a standard long applied by the European Patent Office (EPO).
One immediate benefit of this shift is that UK patent applications involving AI technologies are now more likely to undergo full search and substantive examination by the UK Intellectual Property Office (UKIPO). Previously, many such applications were rejected at an early stage under the Aerotel framework. This change is particularly advantageous for applicants who file first in the UK and rely on the UKIPO’s search and examination reports to guide broader international patent strategies.
However, whether the ruling will substantially increase the number of AI-related patents granted in the UK remains uncertain. The Supreme Court left several key questions unresolved, referring them back to the UKIPO for further evaluation.
Background
The patent application at the centre of the case (published as GB2583455) involves a system that uses an artificial neural network (ANN) to replicate the way humans perceive similarities and differences between information files. The system relies entirely on measurable physical characteristics of the files rather than subjective interpretation.
Its intended commercial application is to recommend media content. For example, if a user enjoys a particular music track, the system can identify and suggest other files likely to produce a similar emotional response.
Initially, the UKIPO Hearing Officer rejected the patent application. The rejection was based on the exclusion of “programs for computers… as such” under Section 1(2) of the Patents Act 1977, which mirrors Article 52(2) of the European Patent Convention (EPC).
The applicant successfully appealed to the Patents Court, which ruled that an ANN is not simply a computer program. However, the Court of Appeal overturned that decision, restoring the UKIPO’s rejection. The dispute ultimately reached the Supreme Court, which delivered its judgment on 11 February 2026.
Legal Framework
The dispute centred on Section 1 of the Patents Act 1977 and Article 52 of the EPC. These provisions establish that patents may be granted for inventions that are:
- New
- Involve an inventive step
- Capable of industrial application
However, certain categories are excluded from being considered inventions. These include:
- Discoveries, scientific theories, and mathematical methods
- Aesthetic creations
- Business or game rules and mental processes
- Computer programs
- Presentations of information
Importantly, these exclusions apply only when the subject matter falls within those categories “as such.”
Three central issues were considered by the Supreme Court:
- Whether the Aerotel test remained valid law.
- Whether an artificial neural network qualifies as a computer program.
- Whether the claimed invention as a whole was excluded from patent protection.
Decision
Issue 1: The End of Aerotel
The first issue carries the most significant implications. It determines how courts and patent examiners interpret the exclusions listed in the patent legislation.
Under the Aerotel four-step test, examiners were required to:
- Properly construe the patent claim.
- Identify the invention’s actual contribution.
- Determine whether that contribution fell solely within excluded subject matter.
- Assess whether the contribution was technical in nature.
The Supreme Court ruled that this framework is no longer valid law. The court agreed with earlier decisions from the EPO Boards of Appeal, particularly G1/19, which criticised Aerotel for mixing two distinct issues: patent eligibility and inventive step.
The Aerotel method focused on identifying the inventor’s contribution to human knowledge, a concept that inherently involves assessing novelty and inventive step. However, these are separate legal requirements and should not be evaluated at the eligibility stage.
Instead, the court adopted the EPO’s “any hardware” approach. Under this model, a claim involving computer-implemented technology can avoid exclusion simply by including technical means, such as a computer, storage medium, or other hardware components.
Although this threshold is relatively low, the court explained that it reflects the wording of Article 52(3), which limits the exclusions to subject matter falling within those categories “as such.”
The Intermediate Step
While adopting the “any hardware” approach, the Supreme Court introduced an additional intermediate step before evaluating inventive step.
This step requires examiners to:
- Break down the invention into individual features.
- Identify which features contribute to the technical character of the invention.
Features that do not contribute technically are excluded from the inventive step analysis.
This filtering process ensures that non-technical aspects—such as abstract ideas or business methods—cannot support a finding of inventiveness.
Importantly, the court confirmed that the existing Pozzoli/Windsurfing test for inventive step will remain in place, rather than fully adopting the EPO’s problem-solution approach.
Issue 2: Is an ANN a Computer Program?
The Supreme Court concluded that an artificial neural network qualifies as a computer program.
The court reasoned that an ANN ultimately consists of instructions that process data in a particular way to generate a result. The applicant attempted to distinguish between hardware-based neural networks and software-based implementations, but the court rejected this distinction.
According to the judgment, both implementations share the same architecture, weight structures, and operational logic. An ANN is therefore an abstract computational structure rather than a physical object. Regardless of the hardware used, it operates as a computer program.
Issue 3: Is the Invention Excluded as a Whole?
Although the invention involved a computer program, the court determined that it also relied on technical components, including:
- Computer hardware
- Databases for storing files
- Communication networks
- User devices
Because these elements provide technical means, the invention cannot be considered a computer program “as such.” As a result, it was not excluded from patentability at the eligibility stage.
Outcome
Based on its findings, the Supreme Court allowed the appeal and overturned the earlier rejection of the patent application. The case has now been returned to the UK Intellectual Property Office for full examination.
The UKIPO Hearing Officer must now determine:
- How does the new intermediate step apply to this specific invention?
- Whether the invention’s technical features involve a genuine inventive step.
Following the decision, the UKIPO has announced several immediate actions:
- Suspension of its previous guidance on AI-related patent examinations
- Updates to the Manual of Patent Practice
- Alignment of UK examination procedures with those used by the European Patent Office
The UKIPO has also stated that each AI patent application will continue to be assessed individually on its merits, and transitional arrangements will be introduced as the new approach is implemented.
Comment
The Supreme Court’s ruling represents an important development for patent law, particularly for inventions involving artificial intelligence. However, its impact extends beyond AI and affects any invention that touches on traditionally excluded subject matter, such as mathematical methods, business processes, mental acts, or presentations of information.
One of the most practical benefits of the decision is the elimination of the Aerotel test, which often prevented applications in fields like AI from receiving full examination. Under the previous system, the UKIPO frequently declined to conduct searches or substantive reviews if it believed the invention fell within excluded subject matter.
With Aerotel removed, applicants should now receive prior art searches and examination reports, providing valuable insights for shaping international patent strategies.
That said, the overall likelihood of patent grants may not increase dramatically. Instead, the legal debate is likely to shift from eligibility to inventive step, where the new intermediate step will filter out non-technical features.
It is also important to clarify that the ruling does not mean that AI has suddenly become patentable. AI-related inventions have long been eligible for patents in the UK and at the European Patent Office when they demonstrate a clear technical effect.
Read A[so:
What the Supreme Court has done is refine the method of evaluating such inventions, not introduce a new category of patentable subject matter.
Some uncertainty remains, particularly regarding how the new intermediate step will operate alongside the Pozzoli test for inventive step. The intermediate step encourages a detailed analysis of individual features, whereas the Pozzoli approach focuses more broadly on the inventive concept of the claim as a whole.
Resolving these tensions may require further legal clarification in future cases.
Overall, the decision is widely viewed as positive. The removal of Aerotel brings UK patent practice closer to the European framework and ensures that applicants engaging with complex technologies, such as AI, will receive the full examination process that supports informed innovation and global patent strategy.
Senior Reporter/Editor
Bio: Ugochukwu is a freelance journalist and Editor at AIbase.ng, with a strong professional focus on investigative reporting. He holds a degree in Mass Communication and brings extensive experience in news gathering, reporting, and editorial writing. With over a decade of active engagement across diverse news outlets, he contributes in-depth analytical, practical, and expository articles exploring artificial intelligence and its real-world impact. His seasoned newsroom experience and well-established information networks provide AIbase.ng with credible, timely, and high-quality coverage of emerging AI developments.