Claudia ANNACKER

Dr. Claudia Annacker is an independent arbitrator and counsel, specializing in international arbitration and public international law, in particular investor-State disputes, inter-State disputes, disputes involving international organizations, and human rights cases. Dr. Annacker has 25 years of experience in international dispute settlement. Prior to January 2024, she was a partner at Dechert and prior thereto Cleary Gottlieb, where she represented sovereign and private parties in more than 35 investment arbitrations, in inter-State arbitrations and before the European Court of Human Rights. She has routinely advised on a wide range of public international law issues, including the law of treaties, State responsibility, international privileges and immunities, international trade law, and State succession. She has also served as an arbitrator in investment treaty and commercial arbitrations.

Dr. Claudia Annacker is a member of several arbitrator panels, including the ICSID Panel of Arbitrators and the SIAC Panel of Arbitrators. She serves on the Court of Arbitration of the Singapore International Arbitration Centre and the Board of the Vienna International Arbitral Centre (President of the Investment Arbitration Committee).
Dr. Claudia Annacker is recognized as a leading expert in international arbitration by Chambers and The Legal 500, described as “a go to person for sovereign states and global companies for investor-State disputes,” “a brilliant arbitration lawyer who has profound knowledge and expertise in handling complex international arbitration cases,” “an investment treaty specialist with phenomenal reputation … profound practical experience and high academic knowledge of international treaty disputes,” “strategy maestro with a unique and impressive presence in the court room” and “highly respected by tribunals and opposing counsel.” She is also noted for her “second-to-none knowledge of theory of international law and arbitration practice.” The Legal 500 EMEA lists her in the “Hall of Fame.” Benchmark Litigation selected her as a “Litigation Star” and named her “Lawyer of the Year France” (2019).

Dr. Claudia Annacker holds a PhD and venia docendi (habilitation) in public international law. She is an adjunct professor at the University of Vienna, where she teaches advanced research seminars in public international law and supervises PhD theses. She has also been a visiting professor at the Paris Ouest Nanterre La Défense University and regularly teaches at other leading universities.