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Enlarged Board of Appeal Releases G 1/19 Decision on Patenting Computer Simulations

Enlarged Board of Appeal Releases G 1/19 Decision on Patenting Computer Simulations


The EPO’s Enlarged Board of Appeal has been considering questions relating to the patentability of simulations in G1/19 and has recently issued its decision.

Computer-implemented simulations are as patentable as any other computer-implemented method.  Nothing is to be changed in the patentability assessment criteria utilised so far, with the clarification that technicality of the simulated system or model does not necessarily impact on patentability

The EPO Enlarged Board of Appeal (EBA) has sought to give further guidance about the patentability of computer simulations in their long-awaited decision in G1/19.  In the writers’ view it is questionable whether clarification, or at least useful clarification, may be achieved with a statement involving the words “not necessarily”.  Fortunately, the Order from the EBA is expressed with greater definitiveness.

The underlying referral to the EBA arose from an earlier appeal – T489/14 (Pedestrian simulation/ Connor) which considered the patentability of an application relating to a computer-implemented method of simulating pedestrian movements within a real environment or building structure.  In T489/14, the Technical Board of Appeal (TBA) found that the simulation did not confer technical character, but they recognised that earlier decisions taken by other TBAs 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. 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?


Maybe unsurprisingly, the EBA held that computer-implemented simulations must be assessed according to the same criteria as any other computer-implemented invention, including the question of whether a claimed technical or non-technical feature contributes to the invention's technical character (T641/00 “Comvik”).  While the use of a computer in the claimed subject matter makes it eligible for patent protection, any technical effect going beyond the normal electrical interactions within the computer on which the simulation is implemented (i.e. any "further technical effect") must be subject to the same considerations for inventive step.  However, in G1/19 the EBA has gone further and defined the “further technical effect” requirement with specific reference to simulation cases as a “technical effect going beyond the simulation’s straightforward or unspecified implementation on a standard computer system”.  In so doing, the EBA touched on the ideas of a “virtual technical effect”, a “potential technical effect” and a “tangible technical effect”, noting that they “fully support the view that a tangible effect is not a requirement under the EPC” and that potential technical effects may be considered if the data resulting from a claimed process is specifically adapted for the purpose of its intended technical use.  However, the EBA noted also that “either the technical effect that would result from the intended use of the data could be considered “implied” by the claim, or the intended use of the data (i.e., the use in connection with a technical device) could be considered to extend across substantially the whole scope of the claimed data processing method”.  The EBA considered these potential technical effects therefore to necessarily become real technical effects when put to their intended use.


For the assessment of whether a computer implemented simulation comprises technical character , 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.  Unfortunately, the EBA 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 EBA, the required technical character needs to be evaluated on a case-by-case basis.  The EBA did, however, make a series of helpful remarks in relation to the assessment of technical character of a simulation:

(i)    A direct link with an external physical reality is not a requirement.

(ii)   A technical contribution may also be established by features within the computer system used to run the simulation.

(iii)  Simulation models as well as the equations representing the model are mathematical – regardless of whether a “technical” or “non-technical” system or process is modelled.

(iv)  A model underlying a simulation may comprise technical character if its purpose is to adapt 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., the accuracy of the simulation), or if it forms the basis for a further technical use of the outcomes of the simulation.

(v)   An algorithm may comprise 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).

(vi)  When relying on a technical improvement based on implementation details, such implementation details should appear as limiting features in the relevant claims.

(vii) The 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.

(viii) The data output from the simulation which reflects the physical behaviour of a system modelled in a computer usually does not comprise technical character, even if the output data adequately reflects the behaviour of a real system underlying the simulation.

The clear message of decision G1/19 is that computer-implemented simulations are as patentable as any other computer-implemented method.  Nothing is to be changed in the patentability assessment criteria utilised so far when computer-implemented simulations are claimed.

In addition, any assessment of patentability for computer simulated method/simulation must be performed within the framework of the landmark Comvik decision, therefore the current Guidelines for Examination are fully confirmed and, hence, reinforced.  However, one practical challenge going forward is 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 requirement for patentability is mirrored in the assessment of specific technical applications of machine learning (AI) and other mathematical methods at the EPO, where claims that are functionally limited to the specific technical purpose are considered patentable.  In contrast, algorithms if claimed in abstract form – isolated from any technical purpose, are not considered patentable.  Limiting a claimed simulation to use for a technical purpose 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.

© 2021 WP Thompson Limited, Lewis Mulholland and Dr Julian Potter assert their moral rights to be identified as authors.

If you have any questions or require legal advice please contact your usual WP Thompson contact or lmu@wpt.co.uk or jmp@wpt.co.uk