Abstract
We report on our implementation of a tableau prover for the description logic ALC, which is based on the EXPTIME tableau algorithm using global caching for ALC that was developed jointly by us and Goré [9]. The prover, called TGC for "Tableaux with Global Caching", checks satisfiability of a set of concepts w.r.t. a set of global assumptions by constructing an and-or graph, using tableau rules for expanding nodes. We have implemented for TGC a special set of optimizations which co-operates very well with global caching and various search strategies. The test results on the test set T98-sat of DL'98 Systems Comparison indicate that TGC is an efficient prover for ALC. This suggests that global caching together with the set of optimizations used for TGC is worth implementing and experimenting also for other modal/description logics.