Economic geography increasingly conceptualises "innovation as a collective action" (Storper, 1996). However, cluster literature often reduces the collective dimension to the circulation of knowledge between local-regional organisations based on various forms of (market, organisational, social, institutional or cognitive) coordination. This paper departs from this grass-roots perspective by discussing the role of collective actions in clusters, i.e. actions developed by a large number of cluster members acting as a group. Empirical evidence drawing on a study of three digital clusters in the Paris region shows that the cluster as a collective entity holds agency and - thanks to reflexive coordination - can contribute to open innovation - including innovation-seeking partnerships in the early stages of cluster lifecycles.