Despite dramatic growth in multidisciplinary research on platforms over the past two decades, epistemological differences have hindered progress toward a coherent theory of what are digital platform organizations and how they quickly disrupt and dominate traditional organizations, threatening their cognitive legitimacy as new organizing forms. This paper examines how organizational rules, norms, routines and practices embedded in social and structural properties give different types of platforms their distinct organizational identities. We present a theory that proposes a typology of digital platforms and lays the foundation for predicting the next generation of digital platform organizations and their potential as disruptive competitive forces in the digital economy. We discuss several emerging questions to stimulate new research streams on digital platforms