Investor-State Arbitration

We handle complex and high-volume Investor-State disputes with a 90% historic win/loss ratio

Our team is highly experienced in representing sovereign States and their instrumentalities in Investor-State disputes in all of the world’s principal arbitral fora. Our multilingual and multijurisdictional Investor-State arbitration lawyers have successfully represented States in the International Centre for the Settlement of Investment Disputes (ICSID), the ICSID Additional Facility, UNCITRAL rules proceedings, the International Chamber of Commerce, the Stockholm Chamber of Commerce, the London Court of International Arbitration, the American Arbitration Association, among others.

Publications such as Chambers and Partners, Global Arbitration Review, Who’s Who Legal, Legal 500 and Latinvex, among others, have recognized our practice and our attorneys among the best in the world. Among recent accolades, Foley Hoag’s ILAP was recognized as “Practice of the Year” by Law360 and named “Arbitration Team of the Year” by Jus Mundi, not only for being one of the best international arbitration practices in the world but also for nominating more women arbitrators in its cases. Jus Mundi highlighted the practice for being “on top of their game with an outstanding track-record in handling complex state-to-state disputes and all types of arbitrations.”
We are known for exclusively representing sovereign States and their entities, and have successfully represented its sovereign clients in multi-million and multi-billion dollar disputes in various sectors, including mining, oil and gas, telecommunications, transportation, and construction.

Areas of Focus

Our attorneys have wide-ranging knowledge and expertise in these areas:
  • Investment arbitration 
  • Contract bases investor-State disputes
  • Bilateral and multilateral investment treaties
  • International Investment Law
  • Civil and Common Law


  • Raiffeisen Bank International AG and Raiffeisen Bank Austria d.d. v. Republic of Croatia. We successfully represented Croatia in an UNCITRAL arbitration under the Croatia-Austria BIT, as well as in parallel proceedings before German courts. We secured a historical decision of the Oberlandesgericht accepting our request that the Claimants’ request for arbitration be inadmissible under EU law in accordance with the European Court of Justice’s Judgment in Achmea that the arbitration provisions in intra-EU investment treaties are void. This was the first time a court in the European Union concluded that the principles of EU law enunciated by the CJEU in Achmea apply beyond the Achmea litigation.
  • Ritika Mehta, Vinita Agarwal, and Prenay Agarwal v. the Oriental Republic of Uruguay. We successfully represented Uruguay in an UNCITRAL arbitration before the PCA under the Uruguay-UK BIT, involving a large-scale iron ore mining project, which Claimants alleged to be worth $3.47 billion. The tribunal unanimously denied jurisdiction and ordered Claimants to pay Uruguay’s legal fees


  • Thomas Gosling and others v. Republic of Mauritius. We successfully helped Mauritius defeat a challenge to its protection of the first UNESCO World heritage site commemorating resistance against slavery. The claim brought by UK investors who sought to turn it into a luxury resort complex was fully dismissed by an ICSID tribunal.


  • Philip Morris Brands Sàrl, Philip Morris Products S.A. and Abal Hermanos S.A. v. Oriental Republic of Uruguay. We successfully represented Uruguay in a case involving claims of breaches to fair and equitable treatment, alleged indirect expropriation and denial of justice arising out of the implementation of tobacco regulations.


Ping An Life Insurance Company of China, Limited and Ping An Insurance (Group) Company of China, Limited v. Kingdom of Belgium. We successfully represented the Kingdom of Belgium in this ICSID arbitration filed by Chinese financial services company Ping An under the Belgium-China BIT. The tribunal held that it lacked jurisdiction ratione temporis because the dispute settlement provisions of the new treaty did not cover disputes that arose before its entry into force.


Explore All

Get to know the attorneys in our Investor-State Arbitration practice.

Baldomero Casado

International Associate

Washington, DC


Diem Huong Ho

International Associate

Washington, DC


Juan Pablo Hugues

International Associate

Washington, DC


Pablo Nilo Donoso

International Associate

Washington, DC


Sudhanshu Roy

International Associate

Washington, DC