Patenting computer-implemented simulation at the EPO

Patentability of software related inventions recently became one of the most discussed topics for patents in Europe. The latest landmark decision G1/19 of the highest legal instance at the European Patent Office (EPO), the Enlarged Board of Appeal, was expected to bring light into the darkness if computer-implemented simulations can be patented. Read our summary of the key takeaways of G1/19 to find out about the latest standpoint of software (computer-simulation) patents in Europe.

The decision G1/19 once again confirmed the current approach, (Comvik approach), applied by the European Patent Office (EPO) for assessing inventive step of computer-implemented inventions. The Comvik approach is now confirmed to be applicable also to computer-implemented simulations.

It is widely acknowledged that, in order to be patentable, computer-implemented inventions (CII) must overcome two hurdles as required by the EPO. The invention has to pass the first hurdle, i.e., the eligibility test under Art. 52 EPC, meaning that the subject-matter of the application must not fall under the “non-inventions” mentioned in Article 52(2) EPC. Secondly, the invention must also pass the second hurdle defined in Article 52(1) EPC, especially with respect to inventive step. As can be seen from Fig. 1 as shown below, the bar for passing the first hurdle is rather low. This hurdle can be simply overcome by making a reference to a computer, e.g., claiming the method as “computer implemented method”, and thus the exclusion under Article 52(2) EPC no longer applies. However, passing the second hurdle with respect to inventive step is usually more difficult. Principles for assessing inventive step of CII, i.e., the second hurdle shown in Fig. 1, were established in decision T 641/00 which is often referred to as the “Comvik approach”.

As illustrated in Fig. 1, according to the Comvik approach, when assessing the inventive step of a mixed-type invention which includes both technical and non-technical features, all features contributing to the technical character of the invention are taken into account. These also include the features which, when taken in isolation, are non-technical, but do, in the context of the invention, contribute to producing a technical effect serving a technical purpose, and thereby contributing to the technical character of the invention. However, features which do not contribute to the technical character of the invention cannot support the presence of an inventive step. Such a situation may arise, for instance, if a feature contributes only to the solution of a non-technical problem, e.g. a problem in a field excluded from patentability.

Fig. 2 shows a simplified form of how and when a “technical effect” or “technical interactions” may occur in the context of a computer-implemented process. In practice, technical input may consist of a measurement and technical output may exist as a control signal used for controlling a machine. Both technical input and output are typically achieved through direct links with physical reality. Adaptions to the computer or its operation can also lead to technical effects and therefore contribute to inventive step. However, things become harsh when it comes to a computer implemented simulation since the intention of a simulation is to get rid of physical reality. In most cases, there isn’t any physical reality that exists in a simulation process at all, except for the computer. Therefore, the room left for applicants to make arguments is very limited.

The first way is to argue that the simulation is particularly adapted to the computer or its functioning (e.g. by specific adaptations of the computer or data transfer or storage mechanisms). Technical improvements to simulations as such could also be achieved by particular details of the implementing software. Merely finding a suitable simulation algorithm is not enough, the design of the algorithm must be motived by technical considerations of the internal functioning of the computer. However, if the applicant wishes to rely on any technical improvement based on implementation details, such implementation details would have to be disclosed in the patent application and should appear as limiting features in the pertinent patent claims. Since computer simulations are often designed so that they can be executed on a plurality of different computer systems, this first way is often a difficult way to argue, since it can not be shown, that the software takes into consideration the special internal functioning of the computer.

The second way is to argue that the output of the computer-implemented simulation has a potential technical effect. As clarified by the Enlarged Board of Appeal, a direct link with physical reality is not a necessary condition to establish technicality. It is sufficient for a computer-implemented invention to have the potential to produce a technical effect. However, in practice, what will be considered as “an adequately defined technical purpose” as required by T 1227/05 might not be evident. The aforementioned T decision which is commonly cited by the patent practitioners will not be as strong as before, since the Enlarged Board indicated that this decision was based on specific circumstances and shall not apply in general. It must be clear from the claim wording that the output of the simulation is solely adapted for its intended technical use. Taken aforementioned it might be very challenging to exclude any potential non-technical use. An example might be an index file as an output. The resulted index file is considered to be technical means, since it determines the way the computer searches information, which search is a technical task.

As clarified by the Enlarged Board in G1/19, the technicality of the computer-implemented simulation is not relevant to whether the simulated system or process is technical. Even if the simulated system or process is technical, it first has to be translated into models and algorithms (i.e. non-technical information) prior to the simulation. Depending on whether they contribute to any technical effect achieved by the claimed simulation invention, they may or may not be taken into account in the inventive step assessment. To put it briefly, the applicants should still essentially focus on the aforementioned two ways for making arguments and drafting the patent specification. Merely improving the model (i.e. calculation of the behavior of a technical system as it exists on the computer) will be considered as non-technical. Therefore, there must be something more than that.

The Enlarged Board in G1/19 unfortunately did not provide an exhaustive list of criteria for assessing whether a computer-implemented process solves a technical problem by producing a technical effect that goes beyond the implementation of the process on a computer. Therefore, still, theoretically, nothing is impossible. However, further technical effect is still heavily dependent on the “technical context” of the invention. Therefore, this aspect will remain the main problem in European patent praxis, namely to convince the Examiner that the problem solved by the invention is technical.

The same considerations also apply to a computer-implemented simulation claimed as part of a design process. The Board found that a design process is normally a cognitive exercise. However, it cannot be ruled out that in future cases there may be steps within a design process involving simulations which contribute to the technical character of the invention. Therefore, merely additionally claiming a cognitive design step will not make the simulation contribute to technicality.


In general, the EPO keeps the door open for all computer-implemented simulations in light of G1/19. However, the EPO is likely to continue applying its relatively strict approach with respect to assessment of inventive step, as confirmed by the practice of other computer-implemented inventions. When drafting the patent application, the applicants and the patent practitioners still need to spend additional effort to either describe in detail how the simulation algorithm impacts the internal functioning of the computer or ensure that the actual output of the simulation has a potential technical effect, or to do both.

Key takeaways:

  • A computer-implemented simulation will be treated similarly to other computer-implemented methods, the Comvik approach (T641/00) has been once again confirmed.
  • Technicality of the simulated system or model does not necessarily impact the patentability of the simulation method.
  • A direct link with (external) physical reality as demanded by T 0489/14 is not a requirement or necessary condition to establish technicality.
  • Citation of the decision T 1227/05 in the current version of Guidelines might not be a strong argumentation anymore.
  • A computer-implemented simulation claimed as part of a design process shall be assessed in the same way as normal computer-implemented inventions.

Should you wish to read the whole decision, click here.