A Technical Board of Appeal of the European Patent Office has referred legal questions to the Enlarged Board of Appeal concerning the patentability of simulations of technical systems or processes. The case is pending under the designation G 1/19. These questions ask in particular whether a computer-implemented simulation of a technical system or process can solve a technical problem which, under European patent law, is a prerequisite for establishing inventive step. This encompasses the question whether such simulations can produce a technical effect that goes beyond the implementation of the simulation on the computer. Depending on the answer from the Enlarged Board of Appeal, a significant impact on the patentability of such simu­lations might have to be expected. This article explains why there are good reasons computer-implemented simulations of technical systems or processes should be treated in the same way as any other computer-implemented invention with regard to ­the assessment of inventive step. Finally, applicants are given a recommendation for drafting European patent applications in consideration of referral G 1/19.