The size of a test-suite has a direct impact on the costs and the effort of software testing. Especially during regression testing, when software is re-tested after some modifications, the size of the testsuite is important. Common test-suite reduction techniques select subsets of test-suites that achieve given test requirements. Unfortunately, not only the test-suite size but also the fault detection ability is reduced as a consequence. This paper proposes a novel approach where testcases created with model-checker based techniques are transformed such that redundancy within the test-suite is avoided, and the overall size is reduced. As test-cases are not simply discarded, the impact on the fault sensitivity is minimal.