The open innovation (OI) paradigm emphasizes the importance of integrating inbound and outbound flows of technology to increase a firm's innovation performance. While the synergies between technology inflows and outflows have been discussed in conceptual OI articles, the majority of empirical studies have typically focused on either the inward or the outward dimension of OI. According to recent reviews of OI literature, there is a need for further research that takes an integrated perspective on this topic and studies the combination of the inbound and outbound dimensions of OI. This paper follows these calls by focusing on technology licensing as the main contractual form for OI, and by investigating the relationship between technology in‐licensing and out‐licensing activities at the firm level of analysis. In particular, this paper argues that technology in‐licensing positively influences the volume of technology out‐licensing through two mechanisms. The first—resource‐based—occurs because in‐licensing investments expand and enrich the firm's technology base, thus increasing its value and, as a result, creating more opportunities for out‐licensing. The second—capabilities‐based—occurs because, due to commonalities between technology in‐licensing and out‐licensing in terms of performed tasks and required skills, repeated execution of in‐licensing transactions contributes to the development of higher out‐licensing capabilities and, as a result, increase out‐licensing volume. These arguments are tested using a panel dataset of 837 Spanish manufacturing firms over the period 1998–2007. Consistent with the predictions, the empirical analysis shows that higher investments in in‐licensing and more extensive in‐licensing experience lead to superior volumes of technology out‐licensing. These results contribute to research on OI and licensing, by empirically showing the existence of positive interactions between technology inflows and outflows and of synergies in the development of absorptive and desorptive capacities.