Thomas Voisin

• Represented a U.S. oil major and a Malaysian oil company in an ICC arbitration against an African State regarding a breach of a stabilisation clause, in a claim reported to be among the largest ICC arbitration claims to date, with more than USD 77 billion in dispute. The clients secured a favourable award on jurisdiction, and the parties then settled their dispute.
• Represents an international energy company and its subsidiaries in three parallel ICC arbitrations against an African State and its state-owned entities regarding the nationalisation of its upstream and midstream assets, the consequences under the E&P contract and JOA, and the impact on the joint venture operating the pipeline in a neighbouring country. The dispute also involves ancillary civil and criminal proceedings in several jurisdictions. The total amount in dispute is over USD 2 billion.
• Represented a European gas buyer in a dispute exceeding €1 billion arising from the price review provisions of a 35-year natural gas supply agreement in the Italian gas market. The client secured an award valued at over USD 1 billion.
• Industrial, Manufacturing & Commercial Disputes: Represented a major French supermarket cooperative in an arbitration initiated by a former commercial partner. The dispute concerned the end of an alliance which had two components: (1) a cooperation for the purchase of goods and (2) an international cooperation for the provision of services. The amount in dispute was EUR 289 million. The parties settled their dispute.
• Represented a Middle Eastern individual in a family dispute over the division of family assets, and ancillary civil and criminal proceedings in several jurisdictions in relation to various frauds committed. The amount in dispute was over USD 3 billion.
• Represented a major French agri-food group in an ICC arbitration against a global management consulting firm. The arbitration was initiated by the consulting firm after a dispute arose between the parties regarding the fees to be paid under a consulting agreement.
• Represented a family and their UAE-registered holding company in two parallel ICC arbitrations over the control of the holding company and the division of assets.
• Represented a major U.S. automotive manufacturer in an ICC arbitration initiated by a European automotive group in relation to the sale of the U.S. automotive manufacturer’s European automotive subsidiaries. The amount in dispute was in excess of USD 180 million. The parties settled their dispute.
• Represented a leading global shipbuilding firm in two parallel arbitrations seated in Switzerland in connection with three government contracts with an African sovereign state for the supply of a package of assets and services, including military vessels and equipment, and fishing vessels.
• Represented a European chemical company in a London-seated arbitration arising from a long-term supply agreement involving complex EU competition law issues.
• Represented clients in disputes involving long-term supply agreements, contract performance, contractual termination, pricing mechanisms, hardship provisions and joint venture arrangements.
• Energy & Power: Oil & Gas: Represented a major European energy trading company in an ICC arbitration against an energy company regarding an oil block located in an African State. The arbitration was seated in Paris and subject to English law. The procedural language was French.
• Represented a major international oil company's German subsidiary in several ICC arbitrations initiated by a European pipeline operator regarding the use of the pipeline.
• Represented a major international oil company in an arbitration against a European State in relation to the closing of a major gas field.
• Gas price reviews: Represented a European energy company subsidiary in arbitration and expert determination proceedings concerning price review mechanisms under a long-term gas supply agreement, with €400 million at stake.
• Represented a West African energy company in a UNCITRAL arbitration concerning the revision of a price formula under long-term LNG sale agreements.
• Represented a French energy company in a gas price review arbitration arising from a long-term supply agreement in the French gas market.
• Represented a European energy company in a dispute arising from oil-indexed gas pricing and changes in market conditions under a long-term purchase agreement, resulting in a favourable settlement.
• Represented a European energy company in a dispute concerning the validity of the termination of a gas supply agreement under a hardship provision.
• Electricity: Represented a French energy company in a dispute concerning the impact of changes in the European electricity market on a long-term cooperation agreement.
• Nuclear: Represented a major French nuclear energy company in an IP arbitration against a U.S.-listed company regarding the failure of their joint venture for the development of a new-generation nuclear fuel product. The dispute was governed by Swiss law. The parties settled their dispute.
• Renewables: Advised and represented investors in one of the largest wind farms in Europe in an SCC arbitration against the designer and the suppliers of the wind farm's turbines, regarding the performance of the wind farm and its consequences on the PPA for the sale of the electricity produced by the wind farm.
• Infrastructure, Construction & Major Projects: Represented a major cross-border rail operator in a mediation and an ICC arbitration against a rolling stock manufacturer with respect to the termination of the contract for the renovation and modernisation of the client’s shuttles. The proceeding was a Paris-seated ICC commercial arbitration governed by French law.
• Represented the developer of an offshore LNG facility in a dispute with a contractor arising out of an EPC contract for the construction of an offshore LNG terminal in Europe.
• Represented a major national oil company in an ICC construction arbitration initiated by a Spanish engineering company and its local subsidiary concerning an EPC contract for the construction of natural gas cooler systems at multiple compressor stations on an existing pipeline.
• Represented a major European engineering and construction company in an arbitration against the employer, a joint venture between major industrial companies in the energy and chemicals sectors, following the termination by the employer of the EPC contract for the construction of a combined heat and power plant in Europe.
• Represented a major European engineering and construction company in an arbitration filed against it by a Saudi subcontractor with respect to a construction project in the Kingdom of Saudi Arabia.
• Represented an African national oil company in a dispute exceeding USD 300 million arising from the construction and operation of a USD 1.7 billion oil and gas facility, involving claims relating to project execution and additional project costs.
• Represented a European construction company in proceedings before French courts seeking the annulment of an ICC award on arbitrator conflict grounds, including proceedings before the Paris Court of Appeal and the Cour de cassation.
• Transportation & Aviation: Represented a European transportation company in parallel arbitration and court proceedings involving railway operators and significant business interruption claims.
• Represented the subsidiary of a European industrial group in an arbitration arising from the supply of aircraft components.
• Investor-State Arbitration: Represented the majority shareholders in the former Yukos Oil Company as claimants in a series of three PCA arbitrations against the Russian Federation concerning the expropriation of their investment in the company. The claims were brought under the Energy Charter Treaty, a multilateral convention governing trade and investment in the energy sector. These cases attracted significant attention in the arbitration community due to the size of the claim, the identity of the parties and the political context surrounding the Yukos matter. The arbitral tribunal ordered the Russian Federation to pay damages in excess of USD 50 billion to the Yukos majority shareholders.
• Represented the ultimate owners of a bank in arbitration against the Republic of Cyprus arising from actions taken by the Central Bank of Cyprus affecting the bank's operations and assets. The claim was brought under the Cyprus-Lebanon Bilateral Investment Treaty. The amount in dispute was in excess of USD 500 million.
• Represented a European power producer in arbitration against an Eastern European state under the Energy Charter Treaty concerning the termination of power purchase agreements put in place during the privatisation of the electricity sector, resulting in an award exceeding €100 million in favour of the client.

Thomas Voisin represents clients in high-stakes international arbitration disputes involving complex commercial, infrastructure, construction, energy and investment issues. Drawing on more than 20 years of experience across common law and civil law systems, he guides clients through substantial claims, parallel disputes and cross-border enforcement risks.

A French and British national, Thomas studied law in France and the UK and is fully bilingual in English and French. He represents clients in arbitrations conducted in English or French under the rules of leading arbitral institutions, including the ICC, ICSID, LCIA and SCC, as well as in ad hoc arbitrations under the UNCITRAL Rules. He also advises on arbitration-related court proceedings, including the recognition, enforcement and challenge of arbitral awards.

Thomas has represented clients in approximately 100 arbitrations, many involving substantial claims, parallel proceedings, multiple jurisdictions and complex technical, commercial and regulatory issues. His sector experience is particularly deep in oil and gas, nuclear, electricity, renewables, automotive and rolling stock, with a strong focus on disputes involving long-term supply agreements, infrastructure assets, energy projects and gas price reviews.

Clients value Thomas’s ability to distil complex legal and factual issues into clear, actionable advice and to robustly defend their interests in disputes at the intersection of commercial, technical and regulatory considerations. Thomas is currently Vice-Chair of the Arbitration Committee of the International Bar Association.