Der Staat als Investor. Staatsfonds und die süße Frucht der Staatenimmunität

International law firms offer to advise sovereign wealth funds (SWF) on legal, tax and regulatory matters, especially by helping them to structure investments in a way that maintains sovereign immunity and tax benefits available to SWFs. To conceive of state immunity as a negotiable prerogative of investing states in private spheres (vis-à-vis private investors or concurring recipient states) is disconcerting and questions the raison d'être of this legal principle as it disconnects immunity from the exercise of sovereign functions of states. Although a restrictive approach to foreign state immunity – excluding commercial state activities from immunity – is widely acknowledged in international conventions, national statutes and jurisprudence constituting the customary international law on state immunity, the legal framework is still highly disparate. It opens the door for states to structure their SWFs and to define the public purpose of the investment at hand in a manner that increases the likelihood of profiting from immunity in the jurisdiction of the recipient state. The article shows how states can profit from the vagueness of the law on state immunity, contrasts this understanding with the doctrinal foundation of state immunity and examines potential legitimatory conflicts. Whilst neither competing private investment vehicles nor other recipient states are particularly vulnerable, the opposite is true for private contract partners of SWFs or investors engaged in the same investment object. The article offers procedural solutions to reduce the risk of SWFs abusing immunity in private law relationships.