SPS-parallelism+SETHEO=SPTHEO. This paper describes the parallel automated theorem prover SPTHEO, a parallelization of the sequential first-order theorem prover SETHEO. The parallelization is based on the SPS-model (Static Partitioning with Slackness) for parallel search, an approach that minimizes the processor-to-processor communication. This model allows efficient computations on hardware with weak communication performance, such as workstation networks. SPTHEO offers the utilization of both OR- and independent-AND parallelism. In this paper, a detailed description and evaluation of the OR-parallel part are given.