Most previous successful open innovation cases originated from large enterprises that have the ability to invest heavily in research and development (R&D) and to generate many new ventures. Conversely, we find only very few successful case studies of small and medium-sized enterprises (SMEs). The difference in the number of cases makes us doubt the appropriateness of open innovation strategy for SMEs. In order to show the relevance of open innovation for SMEs, the current study analyses the impact of external activities related to open innovation on innovation output by means of a logistic regression and compares the results with those of large enterprises. Further investigation was done to assess the relative impact of the external activities by means of a Bayesian network method. In conclusion, the empirical analysis shows that not all open innovation activities of SMEs have a positive effect on their innovation output.
Keywords: open innovation, external R&D, external knowledge, external idea, small and medium-sized enterprises, SMEs, Bayesian network, Korea