Enterprises are usually classified according to two criteria: ownership (public or private) and objectives (for-profit or not-for-profit). Social enterprises, such as nonprofit organizations, cooperatives, and mutual societies, are categorized under the private, not-for-profit sector (the third sector), in contrast with the public sector (the first sector) and the private, for-profit sector (the second sector). In this study, we reconsider this traditional trichotomy and modify it to develop an alternative characterization of social enterprises, along with for-profit and public enterprises, on the basis of a single criterion, i.e., ownership of enterprise. As a tentative conclusion, we argue that the characteristics of social enterprises are not uniform, and that the differences of social enterprises from for-profit and public enterprises are not necessarily qualitative but more often a matter of degree.