As we have reported previously, the High Court’s remarkable decision to overturn a decision of the UKIPO regarding machine learning was handed down late last year. The High Court found that a trained artificial neural network (ANN) was not a computer program as such, and so could not be excluded from patentability.

Today, the Court of Appeal heard the UKIPO’s appeal from this decision. This appeal has been hotly-anticipated since it was first lodged, mainly due to it having a significant impact on how favourably AI innovators would look to engage in the UK’s ever-growing high-tech market. As reported previously, the UKIPO’s grounds of appeal were published last month.

The most notable aspects of the hearing centred around how the terms computer and technical contribution should be interpreted. The UKIPO sought to broadly interpret the former, while narrowly construing the latter. Naturally, Emotional Perception pushed in the opposing direction.

The UKIPO’s Stance

The UKIPO relied on the Aerotel test to assert that the contribution provided by Emotional Perception’s invention is merely the provision of a “better” (or, more semantically relevant) song recommendation to a user by using an ANN. Accordingly, the UKIPO asserted that its contribution is solely within excluded subject matter due to the selection/recommendations of songs not being technical in character, citing the EPO Technical Board of Appeal’s decision in Yahoo!. Moreover, the UKIPO asserted that the “better” aspect of the recommendation is also not technical due to its consideration of semantics. Further, the UKIPO regarded the invention’s use of an ANN to provide the recommended song could not remedy this lack of technical character. 

The UKIPO asserted that a computer should be seen as a machine which receives input data, performs some form of processing using the input data, and outputs the processed data. In light of this interpretation, a program for a computer describes the processing to be performed by the computer. Given this interpretation, the UKIPO suggested that the weights and biases of the invention’s ANN could be considered a computer program, as they enable the nodes and links of the ANN (which may be implemented as hardware, or emulated in software executed by hardware components) to perform the necessary processing of the input song to then output a recommended song. These weights and biases were argued to be a computer program as such (and thus excluded from patentability), due to the resulting song recommendation not being technical in character.

Emotional Perception’s Stance

In response, Emotional Perception argued that the contribution suggested by the UKIPO was too narrow, as it only considered the features which were new compared to the prior art, rather than taking into account the contribution that the invention makes as a whole. They asserted that it would be inappropriate to separate out the weights and biases of the ANN from its nodes and links, as these features are intertwined as a composite whole. As such, there is no clear delineation of “software” from “hardware”, as the UKIPO alleged, but rather a more complex structure which must be taken as a whole.  Thus, Emotional Perception asserted that the contribution that their invention makes does not solely fall within the exclusions of Section 1(2) of the Patents Act, as technical hardware would be required to implement/emulate the ANN.

Regarding the term “computer”, Emotional Perception asserted that the broad interpretation given by the UKIPO would lead to objects such as variable resistors (and even sextants) being seen as computers, with the mechanical arrangements of their constituent parts effectively being the program for the computer.  Emotional Perception thus sought to limit what was meant by a computer as the digital computers which we all know and use nowadays (Lord Justice Birss noting, however, that analogue computers are a thing!).  In light of their narrower interpretation, a program for a computer should be seen as a set of instructions (typically of an “if-then” structure) that a processor of the digital computer carries out to perform the processing on the input data.

Given this, Emotional Perception asserted that the weights and biases of the ANN are not a computer program, as they are not a set of instructions to be enacted by a processor. Thus, the “computer program as such” exclusion could not apply, as there is no computer program to begin with. Rather, the weights and biases should be considered as part of the ANN’s complex structure, not instructions telling the ANN what to do.


The significance of the circumstances surrounding this appeal cannot be overstated. The outcome of this decision may influence the decisions of many AI innovators wishing to enter the UK markets. 

Despite all this, the appeal also highlights the significance of words and their meaning, especially within patent law, where an unfavourable interpretation may lead to refusal of an application or revocation of a patent. As such, the appeal also highlights the importance of using a patent attorney to protect your inventions.  

We will continue to monitor this fascinating case so that we can provide updates.

Please get in touch with our attorneys at if you would like to discuss how this might affect your portfolio, or any specific cases.