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G 1/19 - Patentability of computer simulations in Europe

On March 10th, the Enlarged Board of Appeal at the EPO published its long-awaited decision on questions relating to the patentability of computer-implemented simulations.


The questions referred to the Enlarged Board concerned the assessment of inventive step for a simulation that is claimed “as such” – meaning a computer-implemented simulation comprising only numerical input and output, without interaction with external physical reality.


The body of existing case law about such inventions is limited. It has been suggested that this is because many applicants have chosen to avoid the critical issue, by claiming steps that clearly provide a technical effect as an output of the simulation (for example, reciting the use of the results of the simulation to control a real-world technical process).


The referral to the Enlarged Board sought greater clarity as to how the technical character of a computer-implemented simulation (claimed “as such”) should be determined.


Decision and Commentary on the Decision


The Enlarged Board answered the referred questions as follows (our emphasis added):

  1. A computer-implemented simulation of a technical system or process that is claimed as such can, for the purpose of assessing inventive step, solve a technical problem by producing a technical effect going beyond the simulation's implementation on a computer.
  2. For that assessment it is neither a sufficient nor a necessary condition that the simulation is based, in whole or in part, on technical principles underlying the simulated system or process.
  3. The answers to the first and second questions are no different if the computer-implemented simulation is claimed as part of a design process, in particular for verifying a design.


Overall, the Enlarged Board has held that the assessment of the technical character of a computer-implemented simulation should be no different to the assessment of any other computer-implemented method. In particular, the COMVIK approach (set out in T 641/00) – the established way to apply the problem-solution approach to computer-implemented inventions that include non-technical features – is suitable for the assessment of computer-implemented simulations.


Thus, to assess technical character, differences with respect to the closest prior art are to be determined and only those that contribute to the technical character are to be considered for inventive step.


In this regard, the Enlarged Board noted that a computer-implemented simulation without an output having a direct link with an external physical reality may still solve a technical problem, i.e. “contribute to the technical character”. This may be the case, for example, where the simulation adapts the computer or its functioning.


Furthermore, the Enlarged Board identified that a computer-implemented simulation may also “contribute to the technical character” and solve a technical problem if the outcome of the simulation has a further technical use (and the claim is at least implicitly limited to that use). In other words, if the potential for use of data produced by a simulation is limited to one or more technical uses, then (the production of) such data may have technical character. However, if the output data produced by the simulation has both technical and non-technical uses, then this cannot contribute to the solution of a technical problem across the full scope of the claim.


On the other hand, the Enlarged Board has made clear that a simulation being based on technical principles underlying the simulated system or process does not bestow technical character by itself. If this were a sufficient condition, the Enlarged Board says, it would give computer-implemented simulations a privileged positon within the wider group of computer-implemented methods, without any legal basis.


Simultaneously, the Enlarged Board also holds that such a condition is not a necessary condition for a computer-implemented simulation to possess technical character either. In this way, the simulation of non-technical processes may also contribute to the technical character of the invention, just as – more generally – features which are non-technical may still contribute to the technical character of a claimed invention, when combined with technical features.


The above principles were held to apply equivalently to computer-implemented simulations which relate to design processes. Features relating to a design may or may not contribute to the technical character of the invention, much like any other feature. The Enlarged Board is of the opinion that inventions involving a design process should not receive special treatment, since “design” is not a clear criterion and there could be uncertainties as to the applicability of special rules for design steps.


To conclude, while the Enlarged Board’s decision makes it clear that the technical character of a computer-implemented simulation claimed as such is not dependent on the claim including a direct link to physical reality, the circumstances in which the technical character can be proven are very specific.


Impact on Earlier Case Law


During the course of the appeal proceedings, the applicant cited Technical Board of Appeal decision T 1227/05 (Circuit simulation I/Infineon Technologies). T 1227/05 concerned a simulation of an electronic circuit subject to 1/f noise. The Board of Appeal in T 1227/05 considered the simulation to have a technical effect, even though the claimed invention did not incorporate a physical end product.


While the referring Board of Appeal accepted that T 1227/05 was similar to the case in suit, it questioned the reasoning given in T 1227/05.


The Board in T 1227/05 found that the simulation of an electronic circuit constituted an adequately defined technical purpose, provided that the claim was functionally limited to that purpose. The assumption of many, in light of this finding, was that the type of system or process being simulated was the decisive issue, for the assessment of whether a simulation could be considered to solve a technical problem.


In reaching its decision, the Enlarged Board shifts the emphasis away from this frequently-cited part of the reasoning in T 1227/05. The Enlarged Board cautions that this should not be taken as a generally applicable criterion of the COMVIK approach for computer-implemented simulations. Calculated numerical data reflecting the physical behaviour of a system modelled in a computer usually cannot establish the technical character of an invention, the Enlarged Board concludes.


This does not appear to dramatically change how computer-implemented simulations should be prosecuted, but it does clarify how arguments related to T 1227/05 may be interpreted in future.


Practical Considerations


One practical challenge, for drafting attorneys wishing to take advantage of the new decision, may be how to ensure that a simulation, claimed as such, is indeed sufficiently limited so that the output of the claimed simulation can only be used for technical purposes. This may be easy, or even implicit, for some simulations, but more difficult for others. The limitation will have to be achieved while also respecting the requirement for clarity under Article 84 EPC.


Of course, it should not be forgotten that this criterion does not need to be met by simulations that deliver a further technical effect inside the computer (adapting the computer or its functioning, in a manner going beyond the normal physical interactions between the program and the computer). If the simulation derives its technical character in this way, there is no need to consider the use to which the output data will be put.


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Rob O'Callaghan
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Zachary Jelley
Zachary's day-to-day practice focuses on the drafting and prosecution of electronic and computer-implemented inventions.
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Technical Assistant
Conor studied Engineering at Durham University, where he specialised in Electronic Engineering.