This is the accepted version of the paper.This version of the publication may differ from the final published version. In the current political climate marked by deep economic transformation, social upheaval is fast becoming a preferred avenue for voicing anger and opposition to austerity and the retrenchment of the welfare state (Castells, 2012). Recent instalments of street protests that have swept the European Union from Greece to France and Spain, Bulgaria to the UK have signalled a deep preoccupation of the European citizenry with social justice whilst also underscoring the centrality of horizontal digital media in sparking and fanning protest. Not least, protest has been directed at preserving the existing scope of digital media for unencumbered information and communication, as witnessed in the cross-national mobilisation against the Anti-Counterfeiting Trade Agreement (henceforth ACTA). With this article, we seek to investigate an ostensible process of participatory coordination with
Permanent repository linkFacebook and Twitter, which were both used in the pan-European protests against ACTA.The aim of this study is to conceptualize and evaluate the scope for two modes of coordination it identifies -motivational and resource coordination -by way of a mixedmethod study of data retrieved in the run-up to the last Europe-wide anti-ACTA demonstrations of 9 June 2012.Coordination with social media tools has been principally considered in relation to the accomplishment of collective activities (Bennett and Segerberg, 2012: 749;Bennett et al., 2014). Second, it has been discussed in reference to the formation of participant commitment to collective action (see Garrett, 2006;Juris, 2012; Valenzula, 2013). This article speaks to both interests by assaying the scope for the cooperative rather than organizationally orchestrated development of requisite motivations and resources for collective action through networked communication. Consequently, we set out to delineate and empirically verify the notion of participatory coordination. Below, we begin this work with a brief overview of the Stop ACTA movement followed by a review of the sources informing the research aim and hyponym objectives outlined at the end of the same section. (Bruns and Burgess, 2012;. Both platforms may be viewed as social infrastructures enabling, inter alia, the public display of highly individualized and personalized exchanges (Langlois et al., 2009;Poell, 2014 (2009: 417-19). At the same time, the two services leave distinct imprints on the public communication to which they are applied (Poell, 2014: 719). Twitter hashtags -key words or abbreviations preceded by the hash sign (#) -provide one pertinent illustration of these assertions. Hashtags have been noted for their instrumental role in the raising and publicizing of an issue for discussion (Bruns and Burgess, 2012:804). In that way, a hashtagged topic of public concern such as that of the repercussions of the ACTA agreement may attract myriadTwitter users who in their turn add to di...