Ana S. Pirnia | People | Arnold & Porter

Ana Pirnia's practice focuses on international arbitration, public international law, and anti-corruption. She represents sovereign States in investment treaty arbitrations under the ICSID and UNCITRAL arbitration rules, as well as ad hoc arbitrations. She also advises companies and individuals on investigations and enforcement actions involving the Foreign Corrupt Practices Act (FCPA). Ana maintains an active pro bono practice with a focus on civil rights and immigration.

Ana graduated from Columbia Law School, where she served as the online editor of the Columbia Human Rights Law Review and headed the Columbia Human Rights Law Institute's Human Rights Tracker Project. Ana also worked as a legal intern with the Open Society Justice Initiative, where she authored a chapter of a handbook for designing accountability mechanisms for grave crimes.

Focus Areas

Experience

Gasoducto Sur Peruano S.A. En Liquidación v. Republic of Peru (ICSID Case No. ARB/24/29). Counsel for the Republic of Peru in a pending ICSID arbitration concerning a natural gas pipeline project. The case involves complex issues of sovereign risk, infrastructure investment, and treaty protections in the energy sector.
José Alejandro Hernández Contreras v. Republic of Costa Rica (ICSID Case No. ARB(AF)/25/3). Counsel for the Republic of Peru in a third ICSID Additional Facility arbitration initiated by a Venezuelan investor involving a dispute in the telecommunication sector
Counsel for a U.S. company in an ICC arbitration concerning alleged breaches of risk and revenue-sharing agreements within the aerospace industry.

Sacyr S.A. v. Republic of Panama (ICSID Case No. UNCT/18/6). Successfully represented the Republic of Panama in a high-stakes UNCITRAL arbitration brought by Spanish construction firm Sacyr S.A. under the Panama–Spain BIT. The dispute arose from the Panama Canal expansion project, where Sacyr alleged treaty violations related to cost overruns and contract breaches. The tribunal dismissed all claims, finding they were contractual in nature and not attributable to the State, and awarded Panama over $6.3 million in costs.
José Alejandro Hernández Contreras v. Republic of Costa Rica (ICSID Case No. ARB(AF)/22/5). Successfully represented the Republic of Costa Rica in an investment arbitration brought by José Alejandro Hernández Contreras, arising out of the non-renewal by Costa Rica's electricity regulator of a contract with a local telecommunications company, and involving claims of $25 million. In March 2025, the arbitration was terminated at Costa Rica’s request due to deficiencies in the claimant's offer of security for costs. This case is the first reported dismissal under ICSID Arbitration Rule 63(6).
Latam Hydro LLC and CH Mamacocha S.R.L. v. Republic of Peru (ICSID Case No. ARB/19/28). Successfully represented the Republic of Peru in an investment arbitration filed at ICSID by Latam Hydro LLC and Mamacocha S.R.L. under a contract as well as the U.S.-Peru Trade Promotion Agreement, involving a dispute in the hydroelectric power sector. All claims against Peru were dismissed.
Lupaka Gold Corp. v. Republic of Peru (ICSID Case No. ARB/20/46). Represented the Republic of Peru in an investment arbitration filed at ICSID by Lupaka Gold Corp. pursuant to a bilateral investment treaty arbitration, involving a dispute in the mining sector and claims of over $100 million.
Kaloti Metals & Logistics, LLC v. Republic of Peru (ICSID Case No. ARB/21/29). Successfully represented the Republic of Peru in an investment arbitration filed at ICSID by Kaloti Metals & Logistics, LLC pursuant to a bilateral investment treaty arbitration, involving a dispute in the mining trade sector and claims of over $150 million. All claims against Peru were dismissed, and the arbitral tribunal ordered the claimants to reimburse Peru for the totality of its legal fees and expenses and of its arbitral costs.

Successfully represented a Virginia-based non-profit in an arbitration dispute under AAA Rules with a client management service provider.
Successfully represented a company and its subsidiary in an ICC arbitration dispute over alleged breaches of agreements for the supply of Liquified Natural Gas.
Successfully represented a UAE-based owner and developer of luxury hotels in LCIA arbitration dispute with branded management company and services provider.
Represented a minority hedge fund partner in complex dispute with majority partners under several agreements under ICDR Rules of Arbitration.
Counsel for individual in white collar criminal investigation involving OFAC sanctions.