LAWYER PROFILE
Marie Stoyanov

Marie Stoyanov

Global 2026

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Ranked in 2 practice areas

About

Provided by A&O Shearman

Global

Practice Areas

Marie is Global Co-Head of International Arbitration and specialises in commercial and investment treaty arbitration.

She has advised and represented clients in arbitrations throughout the world, both ad hoc and under all the major institutional rules, including the ICC, LCIA and ICSID Rules in which she has particular expertise.

Marie has substantial experience across all market sectors but her practice focuses particularly on infrastructure, energy, and natural resource disputes, with expertise in disputes arising across the African continent.

With clients that include both international investors and sovereign States, Marie regularly appears as advocate before renowned international tribunals arguing extremely complex cases, often with hundreds of millions of dollars at stake. Marie also sits as an arbitrator herself and has written and spoken regularly about international investment and arbitration.

In addition, Marie has also advised various clients on how best to structure their investment in Africa, Eastern Europe and Asia, in order to take advantage of protections offered by investment treaties and foreign investment laws.

After graduating from ESSEC, Marie studied law and was admitted to the Paris bar in 2003. As a French qualified lawyer, she is naturally used to working in all civil-law environments, in particular those whose law is directly derived from French law (e.g. Algerian law, Egyptian law, Moroccan law, UAE law).

A member of the Executive Board of the European Federation for Investment Law and Arbitration (EFILA), Marie is also an Advisory Board member of the publication Investment Claims, which is published by Oxford University Press.

Chambers Review

Provided by Chambers

Chambers Global Guide

International Arbitration - France

Band 3
Band 3

Individual Editorial

Marie Stoyanov specialises in assisting investors with claims under the Energy Charter Treaty. She also handles investment arbitration on behalf of states.

Arbitration (International) - Europe-wide

Band 4
Band 4

Individual Editorial

Paris-based Marie Stoyanov is regularly mandated by sovereign states for her expertise in ICSID proceedings as well as ECT and BIT claims. She also represents prominent corporates in ICC arbitrations.

Strengths

Provided by Chambers

  • Marie Stoyanov is very articulate, focused and impressive. She is a certainly a lawyer I would recommend. She is also well organised, clear and convincing in the way she structures her arguments.

    International ArbitrationChambers Global Guide
  • Marie Stoyanov is a first-rate advocate who is very good and conducts her cases very well.

    International ArbitrationChambers Global Guide
  • Marie Stoyanov has truly had a stellar career. She is skilled, insightful and someone I expect clients are very happy to have in their corner.

    International ArbitrationChambers Global Guide
  • Marie Stoyanov is very articulate, focused and impressive. She is a certainly a lawyer I would recommend. She is also well organised, clear and convincing in the way she structures her arguments.

    Arbitration (International)Chambers Global Guide

Ranked Individuals at A&O Shearman (416)

Africa-wide

Asia-Pacific Region

Australia

Belgium

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