There is a gap in the theory of acquisition, little investigation have been made on the acquired firm within the acquisition process and in service industries. Because of the lack of research in this area, this research is focusing on acquisition theory and how it positions to the acquired firm rather than the firm making the acquisition. Therefore a need to investigate the acquisition theory on acquired firms on SME: s in the IT-service industry is interesting. To do so, three case studies have been made on three firms that have been acquired. The empirical results from the case studies have shown how the relationship between the parent company and the subsidiary has differences. The company culture and the relationship to the parent firm differs if the parent firm is foreign or not; and if the acquisition process is mutual between two firms rather than a market extension acquisition. By analyzing the data of this research the study show that the previous theories of acquisition are adaptable to implement on firms that have been acquired on SME:s in the IT-service industry.