G1/19 referral: Assessing inventive step for simulation inventions

16 April 2019


Referrals to the Enlarged Board of Appeal are not that common, and typically relate to areas of patentability where there is a conflict in existing case law that precludes a uniform application of the European Patent Convention (EPC). Unsurprisingly, the first referral to the Enlarged Board of Appeal of this year (G1/19) relates to computer-implemented inventions, a field which has always been subject to debate. More in particular, this referral concerns the patentability of simulation methods, and raises some questions on how inventive step is to be assessed for simulations.


Multiple hurdles

Typically, the assessment of patentability of computer-implemented inventions under the EPC imposes two specific hurdles that are applied more rigorously than in more traditional fields such as mechanics or chemistry. Firstly, the European Patent Office (EPO) will investigate whether or not the invention is excluded from patentability under Articles 52(2) and 52(3) EPC, which would be the case if a computer program as such were to be claimed. Secondly, when assessing inventive step, the EPO will use a so-called mixed approach taking into account all technical features, and optionally some non-technical features subject to specific conditions. The first hurdle was dealt with in detail in G3/08, while the present referral mainly relates to the second hurdle.


Exclusions to patentability

Decision G3/08 on the first hurdle was slightly unusual: it found the referral by the President of the EPO to be inadmissible, since it considered there to be no conflicting case law. Nevertheless, the decision still clarified the EPO’s stance on what is considered “a computer program as such”, and how to avoid the exclusion in the sense of Articles 52(2) and (3) EPC. In everyday practice, ensuring that a claimed invention is considered to be more than a computer program as such is relatively straightforward: merely reciting the presence of “a computer” or any other technical feature in a claim otherwise purely directed to a judicial exception causes the exclusion to be lifted.


Inventive step

Once the exclusion in the sense of Articles 52(2) and (3) EPC has been avoided, the assessment of the other requirements of the EPC for computer-implemented inventions is mostly the same as for other types of inventions. However, for inventive step an Examiner will consider the technical contribution of each feature within a claim, which is a less prevalent practice in other invention fields. Examples of features considered technical include computers, reactors, buildings, sensors, etc. If a feature is considered technical, it is subsequently taken into account for the assessment of inventive step; however, even if a feature is considered as non-technical, it may nevertheless be deemed to be technical if it contributes to the overall obtained technical effect. One clear example of such a non-technical feature making a technical contribution is a mathematical formula (normally non-technical) being used to steer a process for producing a chemical product; the mathematical formula becomes technical because it results in an improved technical process i.e. better product yield or properties. However, any non-technical features of a claim such as abstract steps or formulae that do not contribute to the technical effect will remain non-technical, and will not be taken into account when assessing inventive step. Therefore, the EPO uses a mixed approach based on all technical features, and selected non-technical features, when assessing the presence of inventive step. This approach has been thoroughly implemented in the EPO Guidelines for Examination in recent years, providing many examples to help Applicants figure out which features should be taken into account or not.

In the above example, the situation would become more complicated if the claimed method had been directed to a simulation of that process. Should the same mathematical formula no longer be elevated to technical status because the overall effect arises purely in silico and hence equates to a non-technical ‘mental act’? Or should technical status be accorded to the formula because process simulations are a critical part of the design of chemical reactors and processes, ultimately having a real-world technical effect?


The present case – contradiction and legal insecurity

Enter case T 0489/14 before the Boards of Appeal. The patent application in question relates to a computer-implemented simulation of the movement of a pedestrian crowd in a building structure. The simulation tool could be used to aid in architecturally designing venues, such as stadiums and railway stations. The application claimed a computer-implemented method, thus had no problems overcoming the first hurdle. However, citing no documents, the Examining Division refused the application based on a lack of inventive step.

Before the Boards of Appeal, the Applicant cited a previous decision (T 1227/05), whereby a numerical simulation of a noise-affected circuit was found to be a functional technical feature. The Board agreed that the present case was similar to T 1227/05, which should have supported the Applicant’s case. However, the Board was not convinced by the reasoning provided in the previous decision, and felt that even though a simulation may assist in the design of a physical environment, the cognitive process of theoretically verifying a design was fundamentally non-technical. In the present case, the Board felt that the sequence of steps of simulating pedestrian movement could theoretically be carried out as mental acts (albeit with pencil and paper for more complex calculations). The Board felt that a technical effect requires, at a minimum, a direct link with physical reality. Therefore, the Board felt that the invention was not inventive starting from a known general-purpose computer as the closest prior art.

Since T 1227/05 had been implemented in the Guidelines for Examination, and was explicitly cited in the Case Law Book, the Board felt that the present decision could create conflicting case law and legal insecurity. Therefore, the Board decided to refer several specific questions regarding the patentability of simulation methods to the Enlarged Board of Appeal (referral G1/19).


The referral as such

In particular, the following questions are referred to the Enlarged Board of Appeal:

1.            In the assessment of inventive step, can the computer-implemented simulation of a technical system or process solve a technical problem by producing a technical effect which goes beyond the simulation's implementation on a computer, if the computer-implemented simulation is claimed as such?

2.            If the answer to the first question is yes, what are the relevant criteria for assessing whether a computer-implemented simulation claimed as such solves a technical problem? In particular, is it a sufficient condition that the simulation is based, at least in part, on technical principles underlying the simulated system or process?

3.            What are the answers to the first and second questions if the computer-implemented simulation is claimed as part of a design process, in particular for verifying a design?



Any decision taken by the Enlarged Board of Appeal will have obvious ramifications for companies, universities, and research institutes that are actively engaged in process or device simulations. In addition, the referral might give an indication as to how the patentability of other types of computer-implemented inventions will be assessed in the future. De Clercq & Partners will be following this referral closely, and will keep its clients updated once the decision is out.