This article deals with critical shareholding, that is, the action of non-profit organizations that resorts to involvement in corporate ownership as shareholders to promote socially responsible corporate behaviours. Based on the combined use of sociological and anthropological tools, I focus on the attendance of annual general meetings (AGMs) as a gateway to understand the potential and the limits of the transformative power of marginal actors in investment capitalism. My findings suggest that confrontation through share ownership exerts transformative pressures not only on companies but also on activist organizations, which over time are called to redefine their skills, actions and intervention logic to pursue their goals more effectively and report them to their stakeholders. Thus, the analysis of the phenomenon reveals the dialectical nature of the processes that take place in and around the AGM, giving them a place in the complex dynamics of movements and countermovements of finance and their mutual relationship.