This study investigates the mechanisms of intellectual capital (IC) in knowledge‐intensive research centres and universities in the Minalogic cluster of Grenoble, France. We use structural equation modelling to analyse responses from 248 PhD holders. Our results show a positive relationship among human, relational, structural, and intellectual capital outcomes. We first contribute to the early understanding of IC mechanisms in research centres and universities by conducting a quantitative empirical study, which is novel to IC. We support the relation between knowledge‐based human capital and relational alliances capital and highlight the importance of employing PhD. holders. Second, unlike past studies, we offer empirical support that (a) relational alliances capital relates to structural innovation capital and (b) knowledge‐based human capital relates to structural innovation capital. We suggest that research centres and universities should develop an alliance portfolio for innovations. Third, we uncover that structural innovation capital relates to IC outcomes, contributing to the assessment of the economic and social role of public research centres and universities. This study presents managerial implications for policymakers and practitioners engaged in research centres and universities by highlighting the importance of key components of IC.