Abstract
Abstract
This entry explores the key concepts of the customary rules on State immunity in investment arbitration. State immunity is primarily a post-arbitral phenomenon that emerges when successful investors try to enforce an arbitral award and seek assets exempt from enforcement immunity. The entry looks into how investment tribunals use and rely upon concepts derived from the law of State immunity. This has been most prominent when tribunals had to determine whether certain acts allegedly in violation of investment treaty standards could be attributed to host States. It concludes that, due to immunity mostly becoming relevant only in the post-award phase, there is no indication that the limited invocation of State immunity concepts by investment tribunals has influenced general international law and dispute settlement practice.