There is growing evidence that firms increasingly adopt open innovation practices. In this paper we investigate the impact of two such external knowledge acquisition strategies, "buy" and "cooperate", on firm's product innovation performance. Taking a direct (productivity) approach, we test for...

Innovations are rarely generated in complete isolation. Due to inherent uncertainty, high knowledge requirements, and high financial investments, many firms search for external partners to develop new products and processes. However, there is an ongoing debate as to whether firms who cooperate...