Abstract: In the last two decades, scholars, practitioners and governments have underlined the relevance of reporting intellectual capital (IC). Analysing the evolution of IC research (Guthrie et al., 2012, Petty and Guthrie, 2000) and considering the fact that some ‘IC pioneer’ companies, like Skandia, have abandoned IC reporting, a recent stream has pointed out the need to investigate the use of IC reports ‘in practice’ (Dumay, 2013, Guthrie et al., 2012, Mouritsen, 2006) in order to understand whether IC reporting is something relevant or just a managerial “fashion” (Dumay, 2012, Mouritsen and Roslender, 2009, Fincham and Roslender, 2003). Moving from these considerations, the aim of our study is to explore if, how, and why IC reports are used by companies and if, how, and why IC measurement and reporting practices do (or do not) stabilise. In order to achieve this aim, a field study approach was adopted (Lillis and Mundy, 2005, Roslender and Hart, 2003). More specifically, the paper highlights the fact that the IC report is frequently a ‘personal business’ and discusses the determining role of some ‘key’ actors (i.e. project sponsors and project leaders) in affecting if, how, and what kind of evolution IC reports and measurements may undergo. Further, the paper sheds light on how the IC ‘lock‑in’ phenomenon may occur not only in the accounting domain but also in others. Finally, it contributes to confirming the fragility of IC indicators. Differently from the majority of extant studies, this one focuses not only on the production of IC measurements and reports or on their peculiarities, but also on their use. Moreover, it adopts a longitudinal perspective as opposed to focusing on a specific moment in time. Lastly, in order to gain a broader view of IC in practice, this paper offers insights collected from several organizations, rather than from a single case study.