Can Artificial Neural Networks Be Patented? The UK Supreme Court Redraws the Boundaries of Software Patents

• Date: February 20, 2026
• Prepared by: Esenyel Partners
• Decision: Emotional Perception AI Ltd v Comptroller General of Patents 2026 UKSC 3

Summary of the Decision

The UK Supreme Court has issued a landmark decision regarding whether artificial neural networks (ANNs) can benefit from patent protection. The case concerns the patentability of an ANN system developed by a company named Emotional Perception AI Ltd (EPAI), which suggests music files based on human emotional perception.

EPAI’s system compares music tracks in two separate spaces: first, a semantic space based on human-generated meaningful descriptions (expressions such as “happy” or “melancholy”); and second, a feature space based on measurable physical properties like tempo, rhythm, and tone. The core innovation of the system is the establishment of a consistent correspondence between physical similarities and subjective emotional evaluations through a network trained via backpropagation. Once the training is complete, the network can recommend emotionally similar tracks based solely on physical characteristics.

The Legal Issue

Section 1(2)(c) of the Patents Act 1977, the primary regulation of UK patent law, reflects Article 52 of the European Patent Convention (EPC) and excludes “computer programs” from patent protection. However, this exclusion only covers computer programs “as such.” At the heart of the dispute lies the question of whether an artificial neural network is merely a computer program or an invention of a technical nature.

The End of the Aerotel Era

The Supreme Court has abandoned the four-step test adopted in the Aerotel Ltd v Telco Holdings Ltd [2006] decision, which had dominated UK patent practice for approximately twenty years. The Aerotel approach required determining the “actual contribution” of the invention to the state of the art and assessing whether this contribution fell within the scope of the exclusions. This method intertwined the assessment of patentability under Article 52 with the inventive step analysis.

In contrast, the jurisprudence of the European Patent Office (EPO) has evolved in a different direction. According to the “any hardware” principle adopted by the Enlarged Board of Appeal in the Bentley Systems/Pedestrian Simulation (G1/19) [2021] decision, if a claim involves technical means, it qualifies as an invention within the meaning of EPC Article 52(1). The actual filtering process then takes place at the inventive step stage.

Emphasizing the obligation of UK courts to interpret the law as consistently as possible with the EPC under Section 130(7) of the Patents Act, the Supreme Court adopted the G1/19 approach and ruled that the Aerotel test should no longer be applied.

Is an Artificial Neural Network a “Computer Program”?

The Court has accepted that a software-based artificial neural network (ANN) falls within the scope of a computer program in the ordinary sense, even if it is a system defined by trained weights and biases. Artificial intelligence is not a privileged field that exists beyond current legal categories.

However, this finding was not determinative. This is because the statutory exclusion applies only to programs “as such.” In the assessment made within the framework of G1/19, it was concluded that since EPAI’s claims involve technical means such as computer hardware, databases, and network-connected devices, they possess a technical character and cannot be excluded as a program “as such.”

Nevertheless, the Supreme Court refrained from conducting the inventive step assessment itself and remitted the file to the UK Intellectual Property Office (UKIPO) for the purpose of individually identifying the elements of the claims that possess a technical character.

Importance and Implications of the Decision

This decision is of a landmark nature in several key respects:

• First, it officially ends the Aerotel era. From now on, the assessment of patentability under EPC Article 52 is structurally decoupled from the inventive step analysis. This doctrinal clarification will reshape both the examination and litigation processes for software and AI patents.
• Second, the decision confirms the UK’s will to maintain alignment with the EPC in the post-Brexit period. This carries both practical and symbolic significance for patent practitioners operating across multiple jurisdictions.
• Third, the Court has “demystified” artificial intelligence. Artificial neural networks are, in principle, computer programs; however, the real question is whether the claimed features interact with technical means to solve a technical problem.
• Finally, the “any hardware” threshold lowers the hurdle at the eligibility stage but increases the subsequent analytical intensity. Many AI-related claims will now clear the Article 52 hurdle; the decisive battleground will be the inventive step assessment, filtered through the precise identification of features that provide a technical contribution. Claims relying predominantly on abstract data processing or semantic correlations will face difficulties at this stage unless they can demonstrate a concrete technical interaction.

Conclusion

The Emotional Perception AI decision is, beyond being about the patentability of AI, a judgment regarding the restoration of conceptual consistency in computer-implemented inventions. UK patent law now follows a clearer sequence: eligibility under EPC Article 52, filtering of technical features, and subsequently, the inventive step analysis. This restructuring applies not only to AI but also to data-driven systems, fintech applications, simulation software, and hybrid technical-commercial innovations.

As Esenyel Partners, we continue to provide strategic consultancy on how your software and data-driven innovations should be protected within this new legal framework. This realignment in UK patent law necessitates a review of all processes, from the drafting of patent applications to the definition of technical features.