The context of this work is the reconstruction of Petri net models for biological systems from experimental data. Such methods aim at generating all network alternatives tting the given data. For a successful reconstruction, the data need to satisfy two properties: re-producibility and monotonicity. In this paper, we focus on a necessary preprocessing step for a recent reconstruction approach. We test the data for reproducibility, provide a feasibility test to detect cases where the reconstruction from the given data may fail, and provide a strategy to cope with the infeasible cases. After having performed the preprocessing step, it is guaranteed that the (given or modied) data are appropriate as input for the main reconstruction algorithm.