More is not always better: Effects of collaboration breadth and depth on radical and incremental innovation performance at the project level

This study investigates the effect of project-level collaboration breadth (i.e., the number of collaboration partner types) and collaboration depth (i.e., the intensity of the interactions with these partners) on the incremental and radical innovation performance of innovation projects. The econometric analyses, based on a Community Innovation Study sample of 218 innovation projects conducted in German manufacturing companies, reveal inverted U-shaped relationships between collaboration breadth and radical innovation performance and between collaboration depth and incremental innovation performance. These curvilinear effects speak to the high sensitivity of innovation projects to the extent of collaborative activity, which implies that practitioners should exert caution in managing collaborative innovation projects. This study contributes to the understanding of project-level open innovation and to the overall understanding of the performance effects of innovation collaboration, which, following recent assertions in the literature, could be flawed by analyses conducted at the organizational level.