The delegation of authority to private companies in the security domain has certain advantages for states. It optimizes security, lowers costs and eschews accountability. The aim of this article is to examine the implications of the increasing role of private security companies within, at and beyond the borders of state sovereignty. This article argues that the growing power of private security companies in the prevention and the regulation of unauthorized flows of people and goods produces contradictory tendencies for state sovereignty. As private security companies fulfil roles that were previously under the exclusive authority of state actors, states have lost their exclusivity with respect to their coercive and performative roles. Yet, the privatization of security is the result of the calculated decisions of state actors to increase their coercive power against unauthorized border crossers. Even though states' sovereign exclusivity is being weakened with the privatization of the security domain, both state and private actors work towards strengthening states' sovereign authority by excluding and deterring unauthorized movements of people and goods.