Intellectual Capital (IC) can be viewed as knowledge about knowledge, knowledge creation and how such processes might be leveraged into value. Developing a critical understanding of IC requires a historical and contextual understanding of how IC has emerged and how IC is used. This paper, drawing mainly on insights from Foucault and Wittgenstein, conceptualises IC in very generalist terms as both language game and power in order to initiate such a critical understanding. IC is perceived as a social construction and the genealogical focus is on how actors, positions and interests influence this process of social construction. The paper concludes by proposing some methodological guidelines for conducting critical genealogical research on intellectual capital.