Disentangling the human aspects of open innovation: the mediation of absorptive capacity and the moderation of knowledge tacitness

Purpose This paper aims to investigate the role individuals play in the relationships between open innovation (OI), knowledge use, absorptive capacity (ACAP) and innovation by considering knowledge tacitness. Design/methodology/approach This study adopts a mixed method: a quantitative part based on 413 knowledge workers' responses using structural equation modeling and an inductive multi-case component based on 36 interviews. Findings First, the human aspects of the relationship between OI and ACAP depend on the type of external partners involved, whether they are research centers/universities, firms or customers. Second, ACAP fully mediates the relationship between knowledge use and innovativeness. Third, knowledge tacitness moderates the relationship between external stakeholders' interactions and ACAP such that it is more pronounced when knowledge is tacit. Practical implications Firms should adopt a differentiated OI strategy by identifying diverse external stakeholders' contributions, balancing external engagement with robust internal routines and balancing tacit knowledge for long-term capability building with explicit knowledge for operational efficiency. When investing in OI programs, it is important to maintain the right level of ACAP, as OI alone cannot drive innovation. Originality/value Drawing on social exchange theory, this study investigates how individuals share knowledge with external stakeholders through inbound OI, considering ACAP and the tacit nature of knowledge.