Most research on organizational identity tends to adopt an essentialist perspective, usually differentiating between an organization’s identity, which is constructed internally by the organization’s members, and image, which is constructed by external actors. However, an essentialist view on identity does not capture adequately more fluid organizational arrangements, where it is difficult to establish a clear distinction between members and non-members. Therefore, building upon processual views, in this paper we propose to adopt a communication-centered perspective that allows us to examine the formation of organizational identity in more fluid organizational settings. Drawing on an empirical study of the hacker collective Anonymous, we show that organizational identity is formed through public communicative events that are subject to meaning negotiation whether or not actions can be attributed to Anonymous as a collective actor.