16 Februray 2026
The UK Supreme Court handed down the decision in Emotional Perception AI Limited this week. This decision completely changes how all computer-implemented inventions are to be assessed in the UK for both excluded matter and inventive step. Now the UK courts will apply the EPO’s test as set out in Comvik in relation to excluded matter – but will then continue to apply the UK’s Pozzoli test for inventive step.
In this article, we predict how these two very disparate tests based on different legal principles will be combined together by the UK courts and by the UKIPO.
At the time of writing this article, no guidance has been issued by the UKIPO. The Supreme Court decision provided no guidance as to how the two steps should be combined. This is therefore conjecture based on our experience of both UK and EPO practice. This is how we will begin formatting our arguments to the UKIPO until such guidance is issued.
We believe that the Pozzoli test will be modified to add a sub-stage after the step of “Identify what, if any, differences exist between the matter cited as forming part of the “state of the art” and the inventive concept of the claim or the claim as construed”.
This next step may be formulated as “Identify and discount any of said differences identified in step (3)(a) that are considered to not contribute to the technical character of the claims”.
We believe that this additional step at 3(b) would only be used in relation to excluded matter, and would allow the Comvik approach to relatively seamlessly be used in conjunction with the Pozzoli test.
Please read on for the analysis behind this conclusion.
This has been used at the EPO since 2002 to assess the patentability of computer-implemented inventions. It is noted that the EPO uses the problem-solution approach to assess inventive step. The problem solution approach has not been adopted by the UK courts.
Comvik is a conventional application of the problem-solution approach where the differences from the closest prior art are determined, and only those that contribute to technical character are considered for inventive step.
Where a claim relates to a mixture of technical and non-technical features, the Comvik test is applied. This assesses whether each feature of the claim contributes to the technical character of the claims (and in essence, whether each feature is technical or non-technical).
The non-technical features (or at least those that do not interact with the technical features to contribute to the technical character) are then considered to be a constraint to be met and so are supplied to the person skilled in the art in the technical problem. Therefore, these non-technical features cannot contribute to the technical solution and so cannot support inventive step.
This means that for mixed inventions only technical features can support inventive step.
The Pozzoli test (and beforehand the Windsurfer test as it was) has been used for 40 years to assess inventive step in the courts of England and Wales. This is as follows:
(1)(a) Identify the notional “person skilled in the art”;
(1)(b) Identify the relevant common general knowledge of that person;
(2) Identify the inventive concept of the claim in question or if that cannot readily be done, construe it;
(3) Identify what, if any, differences exist between the matter cited as forming part of the “state of the art” and the inventive concept of the claim or the claim as construed;
(4) Viewed without any knowledge of the alleged invention as claimed, do those differences constitute steps which would have been obvious to the person skilled in the art or do they require any degree of invention?
Previously, under the Aerotel decision (now not followed due to the Emotional Perception decision), excluded subject matter was assessed first under a different test. The Pozzoli test was then used in the normal way for computer-implemented inventions that passed this initial test.
Now the Comvik approach is to be used in the UK for the preliminary test – and the vast majority of all claims will pass this preliminary test as at least one feature will be considered technical (such as use on a computer). However, the findings of this preliminary test now have to directly feed into and be considered by the Pozzoli test. Therefore, the Pozzoli test will have to be modified in some way for use with computer-implemented inventions.
At the EPO non-technical features (see G1/19) are split into two camps i) Non-technical features which do not interact with the technical subject matter of the claim, and ii) Non-technical features which do interact with the technical subject matter of the claim. Only the second type of feature can contribute to technical character and so to inventive step.
The Pozzoli test therefore must take these findings into account, as well as allowing non-technical features which interact with the technical features to contribute to inventive step.
As the Pozzoli test filters the novel features of the claim, and as the Comvik approach filters the features that contribute to the technical character of the claim – it makes logical sense to combine these together to form a new step 3 of the Pozzoli test that incorporates both such filters.
This could be in one step – but we prefer two for simplicity. We would leave the first part of step 3 unchanged. We would then add a second part to stage 3 that would discount those novel features that do not contribute to the technical character of the claim. We therefore propose the following amended step 3:
(3)(a) Identify what, if any, differences exist between the matter cited as forming part of the “state of the art” and the inventive concept of the claim or the claim as construed”.
(3)(b) Identify and discount any of said differences identified in step (3)(a) that are considered to not contribute to the technical character of the claims.
Step 4 may also need to be altered slightly to add “Viewed without any knowledge of the alleged invention as claimed, do those remaining differences constitute steps which would have been obvious to the person skilled in the art or do they require any degree of invention?"
This seems to us to be the simplest solution that maintains the Pozzoli test in more or less its current form whilst allowing the Comvik approach to be fed into the assessment of inventive step. This should allow the large body of case law on inventive step to continue to be used without any adverse effect.
This subset of features will doubtless be the most contentious. This will be the class of features that will launch a thousand UKIPO hearings. We feel this is a key and necessary result of the Emotional Perception decision. The Supreme Court has expressly not weighed in on this matter because it is beneficial for a body of lower court (and UKIPO) jurisprudence to build up in order to assess the correct approach.
This is doubly challenging because this interaction will become very case specific concerning the exact technical features and the commercial context associated with a claim – and so will not naturally lend itself to particular tests. This may well be the area where a new list of signposts are developed as general guidance in much the way the AT&T signposts were used for a number of years.
Indications that non-technical features contribute to the technical character could for example include if they are adapted to a specific narrow technical field and so have a technical effect, or if they control or influence a technical feature of the claim. However, there will likely be countless examples argued by attorneys over the coming months and years and we look forward to seeing a rich body of case law develop.
