Mon 15th Mar 2021

Key implications for patent practitioners in connection with computer simulations arising from G1/19

Olaf Ungerer, a partner and European patent attorney in Munich, highlights key lessons for patent attorneys concerning the patentability of computer-implemented simulations, following the long-awaited decision from the European Patent Office (EPO) on the referred questions in G1/19.

See our earlier article ‘Can computer-implemented simulations be protected with a patent in light of the G1/19 decision?


In a nutshell:

  • It is not sufficient to model something (no matter how accurate or complex). A technical problem needs to be solved through the simulation to make it eligible for patent protection.
  • However, the mere fact that a simulation is based on technical principles is not enough on its own to give a claimed simulation technical character. Simply modelling is not itself technical. What is important is the benefit that the model brings about. There must be a technical purpose.
  • Simulations can be protected on their own. A direct link to physical reality is not a requirement. There is no need to protect the simulation within the context of a design or verification process.


History and referred questions:

The EPO Enlarged Board of Appeal (EBoA – highest instance at the European Patent Office) has given further guidance about the patentability of computer simulations in their long-awaited decision in case G1/19.


The underlying referral to the EBoA arose from an appeal considering the patentability of an application relating to a computer-implemented method of simulating pedestrian movements within a virtual environment or building structure. In that appeal, the Board of Appeal (BoA) found that the simulation did not confer technical character, but they recognised that earlier decisions taken by other BoAs (notably Circuit simulation I/Infineon Technologies T 1227/05) had found that a simulation could be technical in itself, i.e. without requiring an additional step of manufacturing a physical object based on an outcome of the simulation. Because of this divergence, they referred the following three questions to the EBA on patenting computer simulations:


  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. [2A] 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? [2B] 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?


Content of the decision:

Not surprisingly, the EBoA held that computer-implemented simulations must be assessed according to the same criteria as any other computer-implemented invention, including the question whether a claimed technical or non-technical feature contributes to the invention's technical character (co-called “COMVIK approach” of T641/00). The use of a computer in the claimed subject matter makes it eligible for patent protection under Art. 52 EPC (first hurdle) (cf. Reasons, point 78). Any technical effect going beyond the normal electrical interactions within the computer on which the simulation is implemented (i.e. any "further technical effect") may be considered for inventive step considerations at the second hurdle. However, for simulation cases, the EPoA has defined the “further technical effect” as follows (cf. Reasons, point 51):


“Technical effect going beyond the simulation’s straightforward or unspecified implementation on a standard computer system”.


For the assessment whether a simulation contributes to the technical character of the claimed invention, it is however not decisive whether a technical or a non-technical system or process is simulated. These principles apply equally if the claimed computer-implemented simulation is part of a design process.


However, the EBoA declined to set out specific criteria that would assist in assessing technical character, on the grounds that it is never possible to give 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. According to the EBoA, the required technical character needs to be evaluated on a case-by-case basis. Nevertheless, the EBoA has indicated that the term “technical system or process” and “technical principles underlying the simulated system or process” should be interpreted broadly (cf. Reasons, point 48). E.g., the appellant’s argument that pedestrians’ movements could be described similarly to the movement of electrons was accepted by the EBoA.


The EBoA has not ruled out patenting simulations such as those in T1227/05, where the claims begin with the text “Computer-implemented method for the numerical simulation of a circuit“. The EBoA stated that computer simulations are not inherently non-technical. But the EBoA also noted that T 1227/05 was based on specific circumstances which do not apply in general.


Answers to the referred questions:

To summarize, the EBoA’s answers to the referred questions included the following statements (cf. Reasons, points 139-144):


Question 1:

“No group of computer-implemented inventions can be a priori excluded from patent protection. […] Like any other computer-implemented method, a simulation without an output having a direct link with physical reality may still solve a technical problem.[…]”


Question 2:

“[…]A simulation is necessarily based on the principles underlying the simulated system or process. Even if these principles can be described as technical, the simulation does not necessarily have a technical character. […] For numerical simulations too it must be examined on a case-by-case basis whether the standard “technicality” criteria for computer-implemented inventions are met. […] In view of this, the Enlarged Board of Appeal is of the opinion that it is neither a sufficient nor a necessary condition that that a numerical simulation is based, at least in part, on technical principles that underlie the simulated system or process.”


Question 3:

“[…] A design process is normally a cognitive activity. However, following the COMVIK approach and depending on the technical context, features relating to a design may or may not contribute to the technical character of a claimed invention. […]”


Implications for patent practitioners

The implications on claim drafting and assessment of further technical effect may be summarised as:


  • a direct link with (external) physical reality is not required in any case (cf. Reasons, point 88);
  • technical contributions may also be established by features within the computer system used (cf. Reasons, point 88);
  • a model and the equations representing the model are mathematical – regardless of whether a “technical” or “non-technical” system or process is modelled (cf. Reasons, point 106);
  • a model underlying a simulation may contribute to technicality if it is a reason for adapting the computer or the way in which the computer operates, or if it contributes to technical effects relating to the results of the simulation (e.g. accuracy of simulation), or if it forms the basis for a further technical use of the outcomes of the simulation ((cf. Reasons, points 110, 111 and 137);
  • an algorithm contributes to the technical character if it serves a technical purpose (e.g. its design was motivated by technical considerations relating to the internal functioning of the computer) (cf. Reasons, point 112);
  • to rely on a technical improvement based on implementation details, such implementation details should appear as limiting features in the pertinent patent claims (cf. Reasons, point 116);
  • the mere calculation of the behaviour of a (technical) system as it exists on the computer and the numerical output of such calculation, should not be confused with any technical effect of the simulation process (cf. Reasons, point 120);
  • calculated numerical data reflecting the physical behaviour of a system modelled in a computer usually cannot establish the technical character, even if the calculated behaviour adequately reflects the behaviour of a real system underlying the simulation (cf. Reasons, point 128).


For more information on patent protection for artificial intelligence, software and computer-implemented simulations, please contact our expert attorneys on 020 7831 7929 or email



This briefing is for general information purposes only and should not be used as a substitute for legal advice relating to your particular circumstances. We can discuss specific issues and facts on an individual basis. Please note that the law may have changed since the day this was first published in March 2021.


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