State and private competition restrictions can be closely connected. Hybrid cases, involving agreements and decisions of undertakings that would be caught by antitrust rules and a corresponding state action give rise to various challenging legal issues. States, as part of their toolkit to shape economic policy, encourage, support or approve market conduct that would normally be condemned as a price or market sharing cartel. The State may also decide to authorise a chamber or other association to regulate market entry, quality of services or prices. In this paper I focus on how state involvement may impact on corporate or individual antitrust liability. The aim is to give an overview of those defenses which companies invoke to defend their cartel-like activities or abusive behaviour whenever they acted under state influence, often manifesting in the form of a legislative or regulatory act.
 By `hybrid cases` I refer to cases where there are two connected actions, one on the side of a state entity, another by an undertaking. In theory, both the state and the companies could be held liable.