I put forward four these concerning phenomenologically clarifying criteria to characterise social entities. The first thesis maintains that social entities have a sui generis ontological status: unlike natural and ideal entities, social entities depend existentially on individuals’ intentionality and are specifically normative entities. The second thesis claims that social entities existentially depend on heterotropic intentionality – i.e. on intentionality that involves at least two individuals –, and not on solitary intentionality. The third thesis identifies at least three different types of heterotropic intentionality: collective, social and intersubjective intentionality. The fourth thesis states that all three types of heterotropic intentionality are effective: they create social entities, even if each of them creates social entities of different kinds.