The structure of share ownership is a key variable for the comparative study of capitalism. The canonical distinction is between concentrated shareholder structures dominated by families and non-financial companies, and dispersed structures dominated by institutional capital pools. However, this distinction has been upended by the rise of giant asset managers—an institutional source of shareholder concentration. At the same time, the rise of extreme wealth inequality points to increased shareholder concentration also amongst traditional blockholders, individuals and families. This paper marshals global, firm-level share ownership data to study these global varieties of shareholder concentration. In addition to finding support for the dual concentration hypothesis, we also offer a detailed quantitative overview of who owns what in the global corporate economy.