What we know about open innovation, unresolved issues, and a checklist for future research

We synthesize and provide a critical overview of the set of quantitative papers on open innovation which have had an influence on analyses of open innovation in a corporate strategy context. We categorize the literature into (a) firms' external search and knowledge sourcing activities, (b) absorptive capacity, and (c) appropriability. We discuss the firm and individual level contributions to each of these literature streams, identifying those contributions specific to knowledge about open innovation and unresolved issues which represent future research opportunities. In addition, we try to draw some lessons in terms of future challenges for open innovation research in relation to the growth and influence of this domain. Specifically, we discuss some specific problems related to the robustness, validity, reliability, and causal identification of open innovation research, and how these might be overcome through a new research approach. We conclude by proposing a checklist for future quantitative empirical studies of open innovation.