Despite a growing number of Corporate Innovation Hubs (CIHs) in recent years, limited attention has been paid to understanding the key problems that arise among organizations collaborating through CIHs. In particular, organizations often experience Not-Invented-Here (NIH) and Not-Sold-Here (NSH) problems, i.e. negative attitudes towards absorbing external knowledge and towards sharing internal knowledge externally. Consequently, many CIHs fail to deliver and are regarded as “innovation theatres” rather than engines of renewal. By drawing upon an inductive multiple case study of five CIHs, their parent companies and associated startups, located in Silicon Valley (USA) and the Gothenburg region (Sweden), the article sheds light on how CIHs can mitigate NIH and NSH problems in knowledge transfer. Specifically, we investigate the causes, consequences and mitigating mechanisms of NIH and NSH problems among the organizations collaborating through a CIH. These findings are presented in a framework that connects causes and consequences with the corresponding mitigating mechanisms. We also present new theoretical implications for the literatures on NIH and NSH.