Julien Maire du Poset

Biography

Julien Maire du Poset is the founding partner of Lead up and a litigator with equal command of commercial litigation and commercial arbitration, before French and foreign courts and arbitral tribunals. He is a member of the Paris Bar and a Solicitor of England and Wales, with more than seventeen years of experience in business law.

He represents companies, shareholders, creditors and public bodies in domestic and cross-border disputes. He accompanies clients at every stage, from the initial urgent application to the enforcement of the judgment or award, and he integrates the enforcement strategy from the design of the proceedings. He handles matters of every size with the same rigour, from claims of a few tens of thousands of euros to disputes exceeding two billion euros, and he is recognised in particular for his work on enforcement in France.

He acts in contractual, shareholder, distribution, transport and logistics, and post-acquisition disputes, as well as in technical judicial expert proceedings, before the commercial courts, the economic activities courts and the courts of appeal across France. He represents French and international companies in institutional and ad hoc proceedings, in France and abroad, including under the rules of the International Chamber of Commerce (ICC), the London Court of International Arbitration (LCIA) and the Association Française d’Arbitrage (AFA), and he sits as arbitrator. He also handles the related court proceedings, including applications in support of arbitration, annulment actions and the enforcement of awards.

Alongside contentious work, Julien advises clients on the negotiation and drafting of international commercial contracts under French and English law, and in mediation and settlement negotiations. He has particular expertise in international sale and distribution contracts, and contributed to the drafting of model contracts published by the International Chamber of Commerce (ICC), including the ICC Model International Sale Contract and the ICC Model Turnkey Contract for Major Projects. He acts across sectors including transport and logistics, telecommunications, pharmaceuticals, SaaS software, online gaming, construction and engineering, distribution, automotive and industry.

Julien practised at leading Parisian law firms dedicated to litigation and international law before founding Lead up in 2017. He is a member of the LCIA European Users’ Council and sits on the organising committee of Tel Aviv Arbitration Week. He is recognised in the Lexology Index 2026 (formerly Who’s Who Legal) for arbitration, published in partnership with Global Arbitration Review (GAR), by Best Lawyers in France for Arbitration and Mediation (2026 and 2027), and by Leaders League among the Recommended arbitrators in France (Arbitrators, France, 2026). He works in French, English, Hebrew and Italian.

Experience

Below is a selection of representative matters across commercial litigation, interim measures, enforcement, arbitration and pre-litigation. The list is illustrative and does not exhaust his practice.

Selected experience in commercial litigation

• Representation of a listed French CAC 40 group in post-acquisition litigation.
• Defence of a client in complex proceedings now in their seventh year, in a case where the opposing party intended to obtain a decision in under twelve months.
• Counsel for an English shareholder in a shareholder dispute governed by English law.
• Counsel for a Monegasque client against a Middle East-based main contractor in a construction dispute in France, also involving parties in the United Kingdom and the United Arab Emirates.
• Counsel for a French company against an English company before the International Chamber of the Paris Commercial Court, concerning a group of contracts for the sale of medical devices.
• Counsel for a French agent against a Turkish company before the International Chamber of the Paris Commercial Court, in an international commercial agency dispute.
• Counsel for a Spanish company against a French entity in a dispute relating to an international contract for cooling equipment.
• Counsel for a Greek company in a dispute concerning the sale of a production line to a French entity.

Selected experience in interim measures and urgent proceedings

• Urgent référé proceedings before the Aix-en-Provence Commercial Court, resulting in the continuation of a contract that had been unilaterally terminated by the counterparty.
• Urgent (short notice claim) proceedings before the President of the Paris Economic Activities Court, resulting in an injunction to cease anti-competitive practices.
• Interim measures in France against a foreign State entity, in enforcement of an international arbitral award.
• Urgent proceedings in support of arbitration to obtain the appointment of a judicial expert in France, on behalf of a French subcontractor.

Selected experience in enforcement and debt recovery

• Ongoing enforcement of an international arbitral award in a Northern European country and in France, under the New York Convention.
• Enforcement in France of a European Enforcement Order (Italian judgment) against a French public entity.
• Obtaining a payment order on behalf of a US creditor against a French debtor company, followed by attachments in the hands of a notary.
• Enforcement measures in execution of a settlement agreement against recalcitrant debtors.
• Recurring debt recovery proceedings for a transport-sector client: payment orders, urgent proceedings and enforcement measures.
• Challenge to the enforcement of an investment arbitration award, on behalf of an asset holder based in Eastern Europe.

Selected experience in arbitration

• Defence of a franchisee in an AFA arbitration involving claims in excess of three million euros, resulting in a settlement of sixty-five thousand euros.
• Counsel for a European company in an ICC arbitration seated in Singapore against an Asian manufacturer, concerning a contract for the design and manufacture of an electronic device.
• Counsel for a Moroccan subcontractor in an ICC arbitration against an international aerospace group, concerning the termination of its contract following a compliance investigation.
• Counsel for a French company in a pre-arbitration settlement relating to the termination of a distribution contract for spirits and liqueurs, governed by English law, following EU sanctions.
• Sole arbitrator in an intellectual property dispute between two European companies, concerning the development of an online platform.

Selected experience in pre-litigation and amicable resolution

• Counsel for an agent subject to a compliance investigation by a major European group, and negotiation of the termination of the contractual relationship, governed by English law.
• Counsel for the shareholders of a group active in the management of healthcare establishments in a shareholder dispute, leading to a settlement agreement reached through mediation.
• Counsel for a Chinese company in a dispute with a French buyer concerning the purchase of medical equipment, leading to a settlement reached after the initiation of court proceedings.

Education

• Qualifying Law Examination, admission as a Solicitor of England and Wales.
• School of Criminal Defence (École de la défense pénale).
• Certificat d’Aptitude à la Profession d’Avocat (CAPA), Paris Bar.
• Master 2, Arbitration and International Trade, Université de Versailles Saint-Quentin-en-Yvelines, France.
• Master, International Relations, University of East Anglia, United Kingdom.
• Master, Business Law, Université de Nice, France.
• Licence en Droit, Université de Nice, France.

Thought leadership

Recent publications

• “Q&A: Conducting Litigation in France”, Lexology, 23 June 2025 (with Ramy Bassily, Anne-Sophie Tonin and Baptiste Rigaudeau).
• “In Brief: Arbitration Formalities in France”, Lexology, 23 June 2025 (with Ramy Bassily, Anne-Sophie Tonin and Baptiste Rigaudeau).
• “Panoramic Dispute Resolution, France”, Lexology, 27 October 2025 (with Ramy Bassily, Anne-Sophie Tonin and Baptiste Rigaudeau).
• “Convention de Singapour sur la Médiation : un outil qui facilite la résolution amiable des litiges internationaux”, Échanges Internationaux, no. 113, p. 21, January 2019.
• Co-author of the MEDEF Practical Guide to the anti-corruption provisions of the Sapin II Act, including turnkey tools to help companies comply with the Act’s anti-corruption provisions and map their risks, 2016 to 2017.
• Co-author of the ICC Model International Sale Contract, 2013 edition, ICC Publication no. 738E.
• Co-author of “Getting the Deal Through: Construction – France”, Lexology / Law Business Research, 2009 to 2014.
• “Obligation pour le demandeur à l’arbitrage de concentrer ses demandes et ses moyens”, commentary on Cass. Civ. 1ʳᵉ, 1 May 2008, Petites Affiches, no. 199, p. 8, 3 October 2008.
• “Le nouveau contrat modèle de vente internationale de l’ICC”, Échanges Internationaux, no. 95, p. 12, third quarter 2012.
• “L’attribution de dommages et intérêts pour non-respect d’une clause attributive de juridiction”, Versailles International Arbitration and Business Law Review, no. 3, 2012.
• “Méconnaissance de la règle de l’estoppel par les arbitres et ordre public international”, commentary on Cass. 1ʳᵉ civ., 19 December 2012, Botas Petroleum, Petites Affiches, no. 86, p. 7, 30 April 2013.
• “Il y a urgence à mieux rédiger et à revoir les clauses de règlement amiable des litiges dans les contrats”, Versailles International Arbitration and Business Law Review, no. 5, 2014.

Recent speaking engagements

• “Resolving disputes involving start-ups”, Paris Arbitration Week – ACE, Paris, 23 March 2026.
• “Too Much Love Will Kill You: Striking the Right Balance in National Courts’ Role in the Arbitration Process”, Vilnius Arbitration Day, Vilnius, 12 September 2025.
• “Where Sanctions and Arbitration Collide: Key Strategic Considerations”, Arbitration Summit, TL4 Disputes, London, 13 May 2025.
• “Midnight Clauses, from the Shadow to the Light: Drafting an Effective Dispute Resolution Clause, Best Practices and Pitfalls to Avoid”, Paris Arbitration Week – ACE, Paris, 9 April 2025.
• “Engaging in the Arbitral Arts: Investment Treaty and International Commercial Arbitration”, English Law Days, Yerevan, Armenia, 8 June 2023.
• “Why Do Business under French Law? What’s Different?”, Tel Aviv Arbitration Week, Tel Aviv, Israel, 28 February 2023.
• “Le temps de la diversité en arbitrage”, MACI Lecture, Paris, 17 October 2019.
• Lectures and training on the ICC Model International Sale Contract, ICC France, Paris, 2013 to 2014.

Academic involvement

• International Business Law, INSEEC Business School, Paris, 2014 to 2017.
• Arbitration and Civil Procedure, École de Formation professionnelle des Barreaux de la Cour d’appel de Paris (EFB), since 2015.

Contact

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

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