Do relationships matter?—Director networks and corporate open innovation

This paper examines the impact of a firm's important social relationship, director network, on its open innovation. By matching the director network data of Chinese A-share listed companies from 2008 to 2018 with manually collected data on joint patent applications, we conduct an empirical study and explore the possible influence mechanisms. The results show that the director network has a significant positive impact on corporate open innovation. The conclusion still holds after endogeneity treatment, propensity score matching estimation, and other robustness tests. Heterogeneity analysis reveals that director networks promote more R&D cooperation among firms than firm-university and firm-research institution R&D cooperation; director networks have a more positive impact on the R&D cooperation activities of non-state-owned firms compared to state-owned firms; moreover, in terms of the type of director networks, independent director networks have a significantly higher positive impact on firms' open innovation than non-independent director networks. It is further found that director networks can facilitate firms' participation in R&D collaborative activities by alleviating firms' financing constraints and reducing transaction costs. This paper enriches the research related to social relations expanding firm boundaries. The findings provide some references for firms to further develop open innovation activities and the construction of innovation systems.