Emotions run high in UK Supreme Court as Aerotel approach rejected

On Wednesday, the UK Supreme Court handed down its highly anticipated decision in Emotional Perception v Comptroller General of Patents, finding that an artificial neural network (ANN) is a computer program, but that Emotional Perception’s claimed ANN invention was not excluded from patentability as a computer program “as such”. In reaching this conclusion, the Supreme Court rejected the traditional “Aerotel” approach to applying the computer program exclusion –  which has been followed and applied by the English courts for nearly 20 years – adopting instead the “any hardware” approach of the European Patent Office (EPO). 

Background

The question at the heart of this long-running dispute is, in essence, whether it is possible to patent an ANN-implemented invention in the UK – here, an ANN which has been trained to recommend files (such as music tracks) to end users based on human perception and emotion (e.g. how the music makes them feel). 

UK patent law excludes computer programs “as such” from patentability and so, naturally, the question arose as to whether ANNs are computer programs and, if so, whether Emotional Perception’s ANN-implemented invention falls within that exclusion. 

Since 2006, the English courts have applied the following four-stage approach (known as the Aerotel approach) to determine whether the computer program exclusion applies: 

(1) properly construe the claim;

(2) identify the actual contribution;

(3) ask whether it falls solely within the excluded subject matter; and

(4) check whether the actual or alleged contribution is actually technical in nature.

Applying this approach, at first instance the UK Intellectual Property Office (UKIPO) found that the computer program exclusion applied and that Emotional Perception’s invention was not therefore patentable. That finding was overturned by the High Court; and the High Court’s decision itself was later overturned by the Court of Appeal, which reinstated the UKIPO’s decision. All of which highlights the complexities surrounding the patentability of inventions of this kind.

On further appeal to the Supreme Court, three core issues were raised: 

1. Should the English courts reject the Aerotel approach?
2. Is an ANN a computer program?
3. Are Emotional Perception’s claims excluded from patentability?

Should the court reject the Aerotel approach?

Perhaps slightly unexpectedly, given its long-standing nature and the lack of debate on this point in the lower courts, the Supreme Court agreed unanimously to reject the Aerotel approach, finding that the Court of Appeal in Aerotel had misinterpreted the relevant provisions of the European Patent Convention (EPC). 

In its place, the Supreme Court adopted the “any hardware” approach, which was endorsed by the Enlarged Board of Appeal of the EPO in 2021 in a case commonly referred to as “G1/19”. Under that approach, an application will not be rejected under the computer program exclusion if the subject matter of the claim involves the use of any hardware, such as a computer. If that (low) hurdle is overcome, the courts will then apply an “intermediate step” to determine which features of the invention contribute to its technical character, before considering whether the invention is novel and involves an inventive step.

In reaching this decision, the Supreme Court gave a helpful reminder of the weight to be given to decisions of the EPO on the meaning of the EPC. Whilst not strictly bound by such decisions, the English courts should “respect and follow the Enlarged Board’s decisions and any uniform jurisprudence of the Boards of Appeal unless convinced that they are wrong or beyond the ambit of reasonable difference of opinion”. 

The Aerotel approach was adopted at a time when there were no decisions of the Enlarged Board on this point and no clear approach at the EPO Board of Appeal level. However, in Aerotel itself, Jacob LJ had alluded to the fact that the English courts might need to reconsider their approach if/when the Enlarged Board ruled on this issue. The Enlarged Board eventually gave such a ruling 15 years later, in March 2021 (G1/19), which not only confirmed a different approach to the English courts but also approved earlier comments from the EPO Board of Appeal that criticised the Aerotel approach as incompatible with the EPC. In those circumstances, and whilst acknowledging the potential disruption changing an embedded approach like the Aerotel approach might entail, the Supreme Court concluded it was right to reject the Aerotel approach and adopt the EPO’s any hardware approach.

Is an ANN a computer program?

With the approach to exclusions settled, the Supreme Court went on to consider whether an ANN is a computer program and therefore whether the computer program exclusion was engaged at all by Emotional Perception’s application. It found that it is and that the exclusion was therefore engaged.

In coming to this conclusion, the Supreme Court dismissed as overly broad the Court of Appeal’s characterisation of a computer as “a machine which processes information”. At the same time, however, it found that “computer” does not need to be confined to the conventional digital computers that we’re all familiar with. Instead, it must be a flexible term that can accommodate technological change, including quantum computers. 

In turn, the definition of “computer program” must be equally broad and capture any “set of instructions capable of being followed by a computer (of any kind)…to produce desired manipulations of data”.

Applying this to an ANN, the Supreme Court found that an ANN is a computer program, and not a computer. 

Is the entire subject matter of Emotional Perception’s claims excluded?

That left the Supreme Court to determine whether Emotional Perception’s application fell foul of the computer program exclusion. Applying the “any hardware” approach, the Supreme Court found that it was “beyond dispute” that the claims were to an invention and not excluded. The claims in question clearly involved the use of hardware, including a computer and a user device.

Given the case before it had only been argued on the basis of the Aerotel approach, the Supreme Court decided not to take things further and remitted the case back to the UKIPO to apply the “intermediate step” and then determine whether Emotional Perception’s invention is patentable. 

Comment

The Supreme Court’s decision in this case has brought about a significant change to the way the English courts will assess exclusions from patentability going forwards, significantly lowering the hurdle that needs to be overcome and paving the way for increased patentability of ANNs and other computer-implemented inventions. In doing so, the decision brings the UK more into line with the EPO’s approach, creating a further measure of harmonisation within Europe.

However, it remains to be seen how the English courts will apply aspects of this decision (such as the intermediate step) in practice, whether this decision will lead to any adjustments in the English courts' approach to assessing novelty and inventive step (the Supreme Court indicated it did not expect any immediate impact but did acknowledge that it “may require some modification”), and whether the changes made will ultimately lead to different outcomes on patentability.