Anne-Sophie Tonin

Biography

Anne-Sophie Tonin is a partner at Lead up and a member of the Paris Bar. A lawyer with more than seventeen years of experience, she has significant expertise in commercial litigation, both domestic and cross-border, in international arbitration, and in alternative dispute resolution.

She advises and represents a French and international client base, ranging from start-ups to large listed companies, at both the pre-litigation and litigation stages. Her matters span a wide range of sectors: agri-food, construction, defence, distribution, energy, telecommunications, transport and logistics, and audiovisual media. Anne-Sophie has also developed a recognised practice in industrial losses and industrial risks, including major judicial expert proceedings concerning infrastructure, energy facilities, and industrial equipment.

Anne-Sophie acts in domestic and international arbitration proceedings, both commercial and investment-related. She handles institutional arbitrations, notably before the International Chamber of Commerce (ICC), the International Centre for Settlement of Investment Disputes (ICSID), the London Court of International Arbitration (LCIA), the Paris International Arbitration Chamber (CAIP), and the French Arbitration Association (AFA), as well as ad hoc arbitrations. She is included on the list of arbitrators of the CAIP. Anne-Sophie also appears before the French courts in disputes relating to the recognition, enforcement, and annulment of arbitral awards.

Having begun her career at an international business law firm in Buenos Aires (Argentina), Anne-Sophie practised for several years at a leading Paris boutique dedicated to the resolution of domestic and international disputes. She then served as Head of Litigation within the legal department of a Big Four audit firm, where she handled investigations opened by the French Financial Markets Authority (Autorité des Marchés Financiers, AMF), the High Council of Statutory Auditors (Haut Conseil du Commissariat aux Comptes, H3C, now the High Authority for Audit, H2A), and the French judicial authorities, as well as compliance matters, in particular in the area of anti-money laundering and counter-terrorist financing.

Anne-Sophie is listed in the Legal 500 Private Practice Arbitration Powerlist: Arbitration France 2023. She is also recognised by Lexology Index 2026 (formerly Who’s Who Legal) in construction, published in partnership with Global Arbitration Review (GAR). She is further ranked in the Leaders League 2026 ranking of the best French arbitrators, as well as in the Best Lawyers 2027 ranking of leading lawyers in international arbitration.

Anne-Sophie works in French, English, and Spanish.

Experience

Below is a selection of representative matters across international arbitration and arbitration-related litigation, commercial litigation, and industrial risks. The list is illustrative and does not exhaust Anne-Sophie’s practice.

Selected experience in international arbitration and arbitration-related litigation

• Counsel for a joint venture composed of a French multinational and an Algerian company in an ICC arbitration relating to a contract for the safety of oil and gas infrastructures in Algeria.
• Counsel for a Middle Eastern company in an ICC arbitration concerning a complex infrastructure project in Africa.
• Counsel for an Asian company against an African company in an ICC arbitration relating to the performance of a commercial contract for the operation of a mine.
• Counsel for a French telecommunications company in the enforcement of an arbitral award against an African State, which involved the seizure of aircraft and buildings in France and Switzerland and an ICC emergency arbitrator procedure.
• Counsel for an international oil company in an ICC arbitration against a South American subcontractor in relation to the non-performance of a maritime services contract relating to oil extraction operations.
• Counsel for a European State in an ad hoc investor-State arbitration brought by a foreign investor in relation to customs measures, under a bilateral investment treaty (BIT).
• Counsel for a South American audit firm in an ICC arbitration relating to the termination of a contract for membership in a professional network.
• Counsel for the energy department of a US industrial multinational group in litigation, ICC mediation and then ICC arbitration relating to the construction, shipment and installation of electrical parts to be integrated into electronics systems, in the context of the construction of a liquefied natural gas (LNG) plant in Texas.
• Counsel for a French food industry company in two annulment proceedings against an LCIA partial award and final award rendered in Paris.

Selected experience in commercial litigation

• Counsel for a global steel and mining company in litigation over the termination of a contract for the transformation of steelmaking gas into electricity.
• Counsel for an international food and beverage group in judicial expertise proceedings and French and Belgian court litigation relating to defects affecting an industrial site.
• Counsel for an industrial group with global expertise in water management in litigation relating to the termination of established commercial relationships with its transport and chemical products subcontractors.
• Counsel for a Jordanian investor in litigation relating to the enforcement of a settlement agreement over the reimbursement of a shareholder loan in a Hong Kong company, and to the calling of a bank guarantee.
• Counsel for a real estate and hotel company in litigation against individual managers of an international hotel group and their statutory auditors for management wrongdoings.
• Counsel for an international vinyl manufacturer in the management of several bankrupt suppliers and in the design and presentation of sale proposals for a company under judicial administration.

Selected experience in industrial risks

• Counsel for a US group specialised in measurement tools and meters in judicial expertise proceedings relating to malfunctions affecting measurement tools used in the energy sector.
• Counsel for an international steel-making group in judicial expertise proceedings relating to defects affecting breakwater facilities at the Port of La Rochelle, France.
• Counsel for an industrial group specialised in water and waste treatment in judicial expertise proceedings relating to a claim arising out of corrosion on the urban heating system of the city of Grenoble, France.
• Counsel for a Finnish industrial group, specialised in industrial equipment for the mining, construction and other process industries, in judicial expertise proceedings relating to malfunctions of portable grinding and sifting systems.
• Counsel for the energy branch of an international industrial group in judicial expertise proceedings relating to defects affecting the lighting system of the Lille subway.

Education

• Certificat d’Aptitude à la Profession d’Avocat (CAPA), Paris Bar.
• Master 2, Litigation, Arbitration and Alternative Dispute Resolution, Université Paris II Panthéon-Assas, France.
• DEA, Private International Law and International Trade, Université Paris II Panthéon-Assas, France.
• Double degree: Maîtrise in Private International Law, Université Paris XI, Faculté Jean Monnet, Sceaux, France, and Translation Certificate in Legal English and Spanish, ISIT (Institut Supérieur d’Interprétation et de Traduction), Paris, France.
• Licence (Erasmus programme), University of Edinburgh, Faculty of Law, Scotland.

Thought leadership

Publications

• “Q&A: Conducting Litigation in France”, Lexology, 23 June 2025 (with Julien Maire du Poset, Baptiste Rigaudeau and Ramy Bassily).
• “In Brief: Arbitration Formalities in France”, Lexology, 23 June 2025 (with Julien Maire du Poset, Baptiste Rigaudeau and Ramy Bassily).
• “Panoramic Dispute Resolution — France”, Lexology, 27 October 2025 (with Julien Maire du Poset, Baptiste Rigaudeau and Ramy Bassily).
• “Arbitration and Tax Law”, PBA Podcasts, Paris Baby Arbitration, January 2025 (with Baptiste Rigaudeau).
• “Conflictos de interés de los árbitros. Deber de revelación y deber de declaración de los árbitros. El punto de vista del derecho francés”, Anuario Latinoamericano de Arbitraje, no. 3, p. 541, April 2014.

Speaking engagements

• “Arbitral Liability: Convergences and Divergences Between French, Spanish and Latin American Systems”, Club Español e Iberoamericano del Arbitraje (CEIA), French Section, CEIA-40 and CFA40, Paris, 21 January 2026.
• “Career Advancement in International Arbitration: Paris Bruncheon”, Club Español e Iberoamericano del Arbitraje (CEIA), French Section, CEIA Mujeres, Paris, 17 January 2025.
• “Référé et mesures conservatoires”, Etats généraux de l’arbitrage: Savoir gérer le contentieux par l’arbitrage, CNBF, Paris, 25 October 2019.
• “Conflicto de leyes aplicables al arbitraje”, 5th International Forum on ICC Arbitration, ICC Committee of Santo Domingo, Dominican Republic, 24 and 25 June 2019.

Academic involvement

• Seminar on international arbitration law, Master 2 in Business Litigation, Université Paris X Paris-Nanterre, 2018 to 2019.
• Seminar on the comparison between common law and civil law systems, Master 2 in Economic and Legal Translation, Université de Cergy-Pontoise, 2016 to 2017.
• Seminar on the comparison between common law and civil law systems, programme “Communication juridique interculturelle”, HEDAC and ISIT, Versailles, 2012 to 2014.

Contact

A.A.R.P.I. Lead up, 12, rue Tronchet, 75008 Paris, France. Telephone: +33 1 45 75 43 44. Email: tonin@leadup-avocats.com. To get a fuller sense of the firm, please visit our Expertise page and our Team page.

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