Introduction
Every year the European Patent Office (EPO) publishes an updated set of Guidelines, with this year’s coming into force on 1 April 2025. One place the wording of the new Guidelines has been expanded upon is around artificial intelligence (AI) and machine learning (ML) inventions.
By way of background, Articles 52-57 of the European Patent Convention (EPC) collectively define what is considered patentable subject matter at the EPO. Of particular interest when discussing AI/ML and other computer-implemented inventions is the wording of Art. 52 (1) which states “European patents shall be granted for any inventions, in all fields of technology …” so long as they are novel (Arts. 54 and 55), involve an inventive step (Art. 56) and are susceptible to industrial application (Art. 57).
The assessment of inventive step is done at the EPO following the “problem-solution” approach This comprises:
1. Determining the “closest prior art”
a. This is supposed to be a single reference disclosing the “most promising starting point” for arriving at the invention. However, an examiner may consider multiple closest prior art starting points and apply the problem-solution approach each time, if each reference can be shown to be an equally valid springboard.
2. Establishing what the EPO calls the “objective technical problem”
a. This requires determining the distinguishing features of the claimed invention from the closest prior art. The objective technical problem is then a hypothetical task of modifying the closest prior art to achieve the technical effects of the invention.
3. Considering whether a skilled person would have found the solution obvious if given the closest prior art and tasked with the objective technical problem.
a. What the skilled person is skilled in is determined by step 1. They are imagined to have been handed the art of step 1 and the task of step 2, rather than what the actual inventor was tasked to do / the problem stated in the application.
Computer-implemented inventions
When it comes to the patentability of computer-implemented inventions at the EPO, the relevant language is “inventions” and “technology” in Article 52 EPC. The case law at the EPO (see for example G 1/19, T 939/92, T 064/00) is very clear that being “technical” is a prerequisite to qualifying as an “invention”. But then what counts as technical? This has been left deliberately ambiguous by the legislator. Art. 52(2) EPC contains a non-exhaustive list of subject matter excluded from patentability at the EPO, amongst them mathematical methods and computer programs, with Art. 52(3) clarifying that these are only considered as non-inventions if claimed ‘as such’. That is, a patent may not explicitly claim a mathematical method, but may be granted if the claimed subject matter has a “technical character” which may be contributed to by a mathematical method.
A technical solution to a technical problem
The logical conclusion of the foregoing is what is referred to in the Guidelines as the “two-hurdle approach” when considering the patentability of computer-implemented inventions. The first, easier to clear, hurdle is that the invention is technical and is not solely related to excluded subject matter. This is to be assessed without reference to the prior art, and requiring the use of a single technical feature such as a computer or specifying that a method is ‘computer-implemented’ in the claim will usually qualify the invention as being technical (this is frequently referred to as the “any hardware” approach). The second, more difficult to overcome, hurdle is evaluation of inventive step following the ‘COMVIK’ approach (as first set out in landmark decision T 064/00). The COMVIK approach involves establishing which features of a claim contribute to the technical character of an invention and then determining if there is an inventive step in the sense of Art. 56 EPC by taking into account only those features that do contribute to the technical character of the invention. The COMVIK approach is thus a specialised variant of the problem-solution approach for dealing with inventions with a mix of technical and non-technical features.
The COMVIK approach was essentially confirmed by the recent decision of the enlarged board of appeal in G 1/19. G 1/19 explains how an invention may have “(i) technical features which contribute, (ii) technical features which do not contribute, (iii) non-technical features which contribute and (iv) non-technical features which do not contribute to the technical solution of a technical problem and thereby potentially to the presence or not of an inventive step.” The COMVIK approach consists of determining inventive step based only on features in classes (i) and (iii). Features under classes (ii) and (iv) are not taken into account.
However, importantly, claimed features of type (iv) (non-technical features not contributing the technical effect of the invention) may impact the problem-solution approach by being provided as ‘constraints’ in the formulation of the objective technical problem. That is to say, the non-technical features which do not contribute to the solution of the technical problem may be given to the skilled person as part of the technical problem they are tasked with solving (this is often referred to as a ‘requirements specification’ for the skilled person).
New EPO Guidelines on patentability of AI/ML inventions
Moving back to the EPO guidelines and Chapter G-II on what counts as an invention, we see that AI/ML inventions have their own subheading 3.3.1 under ‘3.3 Mathematical Methods’. The previous guidance in the EPO Guidelines stated:
“Hence, the guidance provided in G-II, 3.3 generally applies to these computational models and algorithms too. [Old]”
The new Guidelines have been amended to be substantially clearer, stating:
“However, their use does not by itself render inventions related to artificial intelligence or machine learning non-patentable, and the guidance provided in G-II, 3.3 generally applies. This means that, if a claim of an invention related to artificial intelligence or machine learning is directed either to a method involving the use of technical means (e.g. a computer) or to a device, its subject-matter has technical character as a whole and is thus not excluded from patentability under Art. 52(2) or (3). In such cases, the computational models and algorithms themselves contribute to the technical character of the invention if they contribute to a technical solution to a technical problem, for example by being applied in a field of technology and/or by being adapted to a specific technical implementation. [New]”
The EPO has therefore suggested relatively little change to how it examines AI/ML inventions, and there are no changes to the examples the guidelines give compared to the previous version. Instead, it is re-emphasising that AI/ML are a subset of mathematical methods and have technical character as a whole if they are implemented by a computer. Whether the technical features support a finding of inventive step per Art. 56 EPC will then be decided by using the COMVIK approach by looking at which features of the AI/ML invention contribute to the technical solution to a technical problem.
Other changes
There has also been a minor change to the wording in Chapter F-III of the Guidelines regarding (in)sufficiency of disclosure of AI/ML inventions. The new text reads:
“Another example can be found in the field of artificial intelligence if the mathematical methods and training datasets are disclosed in insufficient detail for the skilled person to be able to reproduce the technical effect without undue burden using common general knowledge over the whole scope of the claim. [New]”
This can be compared to the old text, which read:
“Another example can be found in the field of artificial intelligence if the mathematical methods and training datasets are disclosed in insufficient detail to reproduce the technical effect over the whole range claimed. Such a lack of detail may result in a disclosure that is more like an invitation to a research programme. [Old]”
This does not appear to change the substantive meaning of the passage, which is that an Art. 83 objection can be raised for AI/ML inventions if the application does not contain enough information for one skilled in the art to work the invention.
Thoughts
In practice, drafting patent specifications fit for the EPO and prosecuting AI related inventions at the EPO will probably not change too much following the updated Guidelines. Rather, these new Guidelines help stress that the COMVIK approach to evaluating inventive step for inventions comprising a mixture of technical and non-technical features remains the key hurdle to patentability. Applicants and patent attorneys should continue to bear in mind that, at the EPO at least, patentable inventions require a technical character and should contain one or more technical features that solve a technical problem in order to be considered inventive. Ideally those technical characteristics, features and problems should be identifiable in the patent specification as filed, together with a detailed disclosure of the training methods, datasets and algorithms the skilled person would need to put the AI/ML invention into practice.