Inbound open innovation (IOI) refers to the systematic integration of external technologies, knowledge, or know-how into a firm's internal development processes to drive innovation and maintain competitiveness. Despite the recognized potential of IOI in this regard, there is a limited empirical understanding of specific intra-organizational enablers that facilitate its successful implementation. This study addresses this gap by empirically testing and validating intra-organizational enablers for IOI within a theoretically grounded framework. Using multivariate regression analysis on a dataset of 73 German manufacturing companies, we find that IOI project success is strongly contingent on adaptive governance structures that balance strategic oversight with operational flexibility. Our findings therefore reveal that IOI often resembles radical innovation, necessitating flexible and adaptable governance models rather than rigid, formal leadership structures. Specifically, decentralized decision-making at the project level, combined with senior management steering, enhances responsiveness to uncertainty, while standardized knowledge-sharing mechanisms mitigate the challenges of non-repetitive innovation processes. Hence, this study not only provides new insights into the intra-organizational enablers that support IOI but also offers practical recommendations for effectively managing IOI initiatives.