Anne-Sophie Tonin

Biography

Anne-Sophie Tonin is a partner at Lead up and a recognised practitioner in international commercial litigation, international arbitration and alternative dispute resolution. She advises and represents French and international clients, ranging from start-ups to listed companies and multinationals, across a practice that spans contentious proceedings and pre-contentious advisory work in equal measure.

Her litigation practice covers major French commercial disputes and arbitration-related court proceedings, including the recognition, the enforcement, and the challenge of arbitral awards before the international commercial chamber of the Paris Court of Appeal. She advises clients on litigation strategy across French and foreign forums and handles related proceedings in parallel where they arise. Her sectors include agribusiness, construction, defence, energy, telecommunications, transport and logistics, and media.

Her litigation practice flows naturally into international arbitration, where she acts as counsel in both commercial disputes and investor-State proceedings. She appears before the International Chamber of Commerce (ICC), the International Centre for Settlement of Investment Disputes (ICSID), the London Court of International Arbitration (LCIA), the American Arbitration Association (AAA) and the Chambre Arbitrale Internationale de Paris (CAIP), as well as in ad hoc proceedings. She is listed on the roster of arbitrators of the Chambre Arbitrale Internationale de Paris and is recognised in the Legal 500 Private Practice Arbitration Powerlist 2023 for Arbitration France.

Beyond arbitration and commercial litigation, Anne-Sophie has developed a particular expertise in industrial risks, including significant judicial expertise proceedings on infrastructure, energy installations and industrial equipment.

Anne-Sophie has a strong Latin American dimension to her practice. She began her career in Buenos Aires, Argentina, is fluent in Spanish, and remains actively engaged in the Latin American arbitration community through her publications and speaking engagements.

After practising at an international business law firm in Buenos Aires, she spent several years at a leading Paris-based boutique specialising in domestic and international dispute resolution. She subsequently served as Head of Litigation in the Office of the General Counsel of a Big Four audit firm, where she handled investigations initiated by he French Financial Markets Authority (Autorité des Marchés Financiers, AMF), the French Regulator of Statutory Auditors (Haut Conseil du Commissariat aux Comptes, H3C now H2C) and the French judicial authorities,, as well as compliance matters relating to anti-money laundering and counter-terrorist financing.

Anne-Sophie is admitted to the Paris Bar and works in English, French 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.