
International Arbitration: Investor-State Arbitration
UK Guide 2026 : UK-wide
Rankings

Ranked Individual
Ranked Individual
About
Provided by Volterra Fietta
Volterra Fietta has one of the world’s largest investor-State arbitration practices. It represents States and foreign investors in investment treaty arbitrations before ICSID and other arbitral institutions. In addition, the firm regularly represents governments in State-to-State arbitrations under the PCA and UNCLOS Annex VII rules as well as private and public entities in commercial arbitrations before the ICC, the LCIA and other arbitration centres.
In two ICSID arbitrations against Venezuela, Volterra Fietta recently secured a USD 455 million award for OI European Group and a USD 370 million award for Koch Minerals and Koch Nitrogen International. Led by Robert Volterra and Álvaro Nistal, the firm then successfully represented OI European Group in ICSID annulment proceedings initiated by Venezuela. The annulment application was rejected in its entirety and Venezuela was ordered to bear the entirety of the proceedings’ costs.
Equally, led by Robert Volterra and Graham Coop, the firm successfully represented Barbados in an UNCITRAL arbitration brought by a Canadian investor. The firm achieved the complete dismissal of all claims and USD 3 million in costs to Barbados.
The firm is currently representing Croatia in five ICSID arbitrations. Among other clients, the firm also is representing Egypt, Nigeria and subsidiaries of Koch Industries in multiple high-profile arbitrations and annulment proceedings.
Clients (8)
- The Arab Republic of Egypt
- Barbados
- The Republic of Croatia
- The Dominican Republic
- Koch Industries Inc., United States
- The Federal Republic of Nigeria
- The Republic of Lithuania
- Owens-Illinois Inc., United States
Industries (15)
- Hydrocarbon concessions
- Energy and natural resources
- Telecoms
- Power and electricity
- Shipping
- Heavy and light manufacturing
- Petrochemicals
- Banking and financial services
- Tourism
- Lotteries and gaming
- Water and sewerage concessions
- Construction
- Agriculture
- Food production and distribution
- Sovereign debt
Chambers Review
Provided by Chambers
Work Highlights
Provided by Chambers
Volterra Fietta continued to represent the Republic of Croatia in an ICSID arbitration concerning the legislative measures enacted by Croatia to contain the fallout of the financial crises in Croatian housing and consumer credit.
Strengths
Provided by Chambers
Volterra Fietta continuously adapts and provides creative solutions to overcome roadblocks and unforeseen hurdles.
International Arbitration: Investor-State Arbitration respondentUK
Notable Practitioners
Provided by Chambers
Band 1 
Band 1 
Robert Volterra
Robert Volterra is a formidable arbitration specialist with long-standing expertise in investor-state arbitration. He attracts an impressive international client base with a broad caseload of complex investment treaty claims, and is experienced in acting as both counsel and arbitrator. Robert is an exceptional lawyer.
International Arbitration: Investor-State Arbitration respondentUK
Ranked Individuals at Volterra Fietta (2)
Members
Provided by Volterra Fietta

Gunjan Sharma

Peter Flint


Ahmed Abdel Hakam
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