Major shake-up in assessment of AI inventions in the UK

The Supreme Court’s judgment in Emotional Perception AI Limited (Appellant) v Comptroller General of Patents, Designs and Trade Marks (Respondent) was released on 11 February 2026.

The headline from this judgement is that the Aerotel approach has been abandoned in the UK and is replaced by the Enlarged Board of Appeal (EBoA)of the European Patent Office (EPO)’s approach in the G1/19 decision issued in 2021.

Despite the UK Intellectual Property Office (UKIPO) and the European Patent Office (EPO) using the same criteria to assess whether or not an invention is excluded from patentability, there has historically been divergence between how the criterion that excludes “a program for a computer as such” is interpreted. A general perception is that the EPO has been rather more permissive and this judgment, which will now bring the UKIPO more closely into line with the EPO, seems on its face to be a boost for applicants in the UK. 

Background to the case

UK patent law contains some statutory exclusions in relation to subject-matter that is eligible to be patented. Section 1(2)(c) of the Patents Act 1977, for example, declares that “a program for a computer ... as such” is not an invention for which a patent can be granted. This is mirrored in the European Patent Convention (EPC)

The invention at issue in the present case uses an artificial neural network (ANN) to replicate the similarities and differences which a human user might subjectively perceive between different files of information by reference in entirety to objectively measurable physical properties of those files. The commercial purpose of this is to enable a user to obtain recommendations of a file calculated to elicit a similar emotional response to a file that the user already likes. Such recommendations already exist but the claimed invention is allegedly quicker, more accurate, and provides better recommendations.

The UK Intellectual Property Office (UKIPO) rejected the claimed invention on the basis that it fell within the statutory definition of a “program for a computer…as such”. This decision was overturned on appeal to the High Court but, on counter-appeal by the UKIPO to the Court of Appeal, the original UKIPO decision was restored. A final appeal to the Supreme Court was then made by Emotional Perception AI Ltd.

Supreme Court judgement

The Supreme Court began the delivery of their judgement by acknowledging that the UK Patents Act aims to bring UK patent law as close as possible into conformity with the EPC.

The question in this appeal is whether the claimed invention is a program for a computer as such and how that question is to be addressed.

In this regard, it is the Aerotel approach which has been followed to date. However, it was noted when the Aerotel approach was devised that there was no relevant decision of EBoA to guide the UK courts and the decisions of the lower, technical boards of appeal appeared to be in conflict with each other. It was remarked upon at the time that the Aerotel approach might need to be reconsidered if the EBoA was ever to issue a decision concerning this matter.

G1/19 is the EBoA decision that has been awaited in this regard. G1/19 described the Aerotel approach as being incompatible with the true meaning of the EPC and as being based upon a misunderstanding of the word “invention” in Article 52 EPC.

In the present case Aerotel has continued to be applied by the UKIPO, High Court, and Court of Appeal with no suggestion from any party that it should not be, but the point has now been raised before the Supreme Court as to whether Aerotel should be continued to be applied or whether it should be replaced by the G1/19 approach. This became the main and decisive issue in the appeal and it was unanimously decided that the Aerotel approach should now be abandoned and replaced by those parts of the G1/19 approach which implement the EboA’s interpretation of Article 52 EPC.

The reasons for this are as follows:

1. G1/19 described Aerotel as incompatible with the EPC and Aerotel itself rejects the main plank of G1/19 (i.e. the “any hardware” test). These are not to be considered different methodologies within an acceptable range.
2. G1/19 cannot be described as obviously wrong beyond the bounds of reasonable opinion, which is the standard by which UK courts may not respect decisions of the EBoA.
3. The central criticism of Aerotel by the EBoA (that it misunderstood the word “invention” as used in the EPC) has real force.
4. The comptroller’s argument that the two approaches will always produce the same outcome is not capable of proof and is in any case not a good reason to continue using the Aerotel approach.
5. Adopting G1/19’s interpretation of Article 52 EPC will not involve overturning the Supreme Court’s approach to assessing novelty and inventive step from Pozzoli. 

The Supreme Court applied G1/19 to the facts of this case.

The Supreme Court was in broad agreement with the UKIPO and Court of Appeal in regards to finding that the ANN which lies at the heart of the claimed invention is or includes a program for a computer. The ANN may be implemented hardware or software form but in either case is in essence a program for a computer, the computer being either the single purpose box of nodes and wires of a hardware ANN or the conventional multipurpose computer on which a software ANN is run. 

But the Supreme Court concluded that the claimed invention is not to be considered a program for a computer as such in light of G1/19 because it includes hardware. The UKIPO was therefore wrong to reject the claimed invention on the grounds of it being a program for a computer as such, but the implication here seems to be that the application would have failed under Aerotel, which does not include the “any hardware” test. 

A new “intermediate step”

Of important note is that the approach under G1/19 does not move directly from patent eligibility under the “any hardware” test straight into an assessment of novelty and inventive step. An “intermediate step” is instead included. This intermediate step is for assessing the eligibility of features of the claimed invention to contribute to inventive step.

The intermediate step in question can be summarised as identifying features, whether technical or non-technical, which contribute to the technical character of the invention as a whole. Only those features can be taken into account for inventive step. Accordingly, just because the claimed invention as a whole is not considered to be a program for a computer as such, does not mean that any feature of that claimed invention may now be taken into account when deciding if the invention is novel and inventive (e.g., non-obvious).

The Supreme Court declined to decide on which features of the claimed invention pass this intermediate step but gave guidance as to what that intermediate step involves in a UK context and refers the case back to the UKIPO for the application of that guidance to this claimed invention.

The Supreme Court’s guidance includes the follow points:

The intermediate step is not just a part of EPO practice, like its problem and solution approach to inventiveness. It is a necessary part of the process of applying at least Articles 52 to 56 EPC, because the invention threshold provided by the Board’s “any hardware” interpretation of Article 52 is too low to enable the invention reliably to be tested for novelty and inventive step.

It is open to the UKIPO and to the UK courts to adopt any appropriate method of identifying the technical character of the invention, viewed as a whole, as the necessary first part of carrying out the intermediate step. An example of an appropriate method might in a particular case be to identity the alleged “inventive concept” of the claim, as explained in Pozzoli.

The G1/19 approach of dissecting the subject-matter of the invention into its component features for a review of the contributory role of each feature to, or interaction with, the technical character of invention viewed as a whole stands in sharp contrast to step 4 of the Aerotel approach, which requires a holistic check to see whether the contribution of the claimed invention, viewed as a whole, is technical in nature.

The intermediate step only arises if the invention as a whole is considered to be technical in character, by reason of having passed the “any hardware” hurdle. Again, this is a significant difference from step 4 of the Aerotel approach, which is the concluding stage of deciding whether the subject matter of the claim amounts to an invention at all.

It is not relevant, at the stage of the intermediate step, whether the technical character of the invention appears to be novel or inventive. The jumbling up of invention with novelty and inventive step by Aerotel’s focus on “contribution” (defined as that which, as a matter of substance rather than form, the inventor has really added to human knowledge) is one of the principal criticisms of Aerotel by the EBoA.