Curtis Recognized as Leading Firm in Legal 500 UK 2026

Once again, Curtis has been recognized as a Leading Firm in multiple practice areas by Legal 500 in its 2026 edition. The International Arbitration, Commercial Litigation, Public International Law, and Oil & Gas groups were ranked, with numerous individual recognitions also received, as attested by glowing client testimonials.

Public International Law

Consistently recognized for representing sovereign nations in investor-state arbitrations, the team's experience spans maritime delimitation, state immunity, and international human rights law issues, as well as providing representation before international courts. Leading the 'absolutely exceptional' PIL team, Charles Buderi and Luciana Ricart, also described by clients as ’a powerhouse’, both advise on PIL issues as well as investment arbitrations, primarily acting for sovereign states and state entities.

As well as partners Charles Buderi, Luciana Ricart and William Hampson, Lise Johnson is also recognized as a Recommended Lawyer by Legal 500, whose practice encompasses human rights and business, climate change, and international investment law.

Key client testimonials:

• ‘The Curtis team I work with is absolutely exceptional. They are people with excellent legal knowledge and are always available to clients. They work quickly, efficiently, and deliver high-quality results.’
• ‘Luciana Ricart is a wonderful lawyer. She has extensive legal knowledge, great intuition, and is meticulous and very smart.’
• ‘The Curtis PIL team has reams of experience, and is a pleasure to work with - the dream combination.’
• ‘Luciana Ricart is a powerhouse and someone who can be trusted with any matter. Her work ethic and substantive knowledge make her a special commodity. William Hampson and Claudia King are going to be brilliant stars in the future, too.’
• ‘The firm is dynamic, on the cutting edge of legal developments, and great to work with.’
• ‘Luciana Ricart is at the top of her game and streets ahead in terms of expertise in the area of public international law.’
• 'Curtis' public international law team is highly experienced, discreet, and strategic in handling complex state matters.'
• 'The individuals at Curtis stand out for their expertise, professionalism, and clear communication.'

Projects, Energy & Natural Resources - Oil & Gas

The Oil & Gas group are known for their long-standing representation of governments, national oil companies, and regulators in the sector. Marc Hammerson, ranked as Leading Partner, focuses on M&A, project development, and restructuring in the oil and gas industry. Odysseas Stergianopoulos, recognized as a Recommended Lawyer, specializes in international arbitration and litigation, frequently representing sovereign states and state-owned entities in energy-related disputes.

Key client testimonials:

• ‘The team led by Marc Hammerson is highly regarded for its expertise in oil and gas M&A. They combine strong technical capabilities with a deep understanding of the commercial and strategic drivers behind complex energy transactions, particularly in the upstream space.'
• 'The team is known for its pragmatic advice, responsiveness, and ability to manage cross-border matters efficiently – making them a trusted advisor on high-value and strategically important deals.’
• ‘Marc Hammerson is a standout practitioner in oil and gas M&A – commercially astute, technically excellent, and highly experienced in navigating complex cross-border transactions in the energy sector.’
• ‘The energy practice is distinguished by its deep expertise in the oil and gas sector. Their team possesses a profound understanding of the industry's regulatory landscape, commercial dynamics, and technical complexities.'
• 'With extensive experience handling high-stakes transactions, negotiations, and disputes, they consistently deliver strategic, forward-thinking solutions tailored to the evolving challenges of the global energy market. Their ability to navigate complex legal frameworks and craft innovative strategies has proven invaluable.’
• ‘Marc Hammerson has a real-world understanding of oil and gas projects work, and a depth of experience which I feel fortunate to be able to access.'
• 'The firm and its team are very experienced in their field. They are very efficient in their delivery and their billing rates are reasonable compared to other firms offering similar services. Their team's resilience to the needs of the client and the project is very effective in ensuring a timely delivery of their scope of work.'

International Arbitration

Known for representing sovereigns in investor-state and inter-state disputes, the London team also acts for multinational corporations in international commercial arbitrations. Charles Buderi, recommended also in this practice area, is experienced in ICSID, ICC, DIAC and DIFC-LCIA arbitrations. Partners also recommended are Luciana Ricart, Lise Johnson, William Hampson and Justin Jacinto.

Key client testimonials:

Other Legal 500 Recommended Lawyers in the group include: Alessandro Rollo, Salah Malas, Odysseas Stergianopoulos, Belén María Ibañez and Arthad Kurlekar.

• ‘A wonderful arbitration team that is able to manage highly-complex and sensitive litigation.’
• ‘It is a dream working with them as they have a deep understanding of the underlying legal issues, which they are able to combine with an extraordinary strategic insight and feeling.’
• ‘The Curtis arbitration team is highly responsive and understanding of clients’ precise needs.’
• 'The Curtis team works seamlessly with in-house legal departments and achieves remarkable results.'
• ‘William Hampson masterfully summarises complex issues, digs into all of the facts, and is always available to answer (and clarify) questions in a clear way. He runs his team in an excellent and efficient manner, and is very easy to work with.’
• 'Highly experienced in representing sovereigns. They are efficient and stand out for their services.'

Commercial Litigation: Mid-Market

The London commercial disputes team represents a range of international and domestic clients, including sovereign states and governments. The team has a focus on work involving UK and EU financial sanctions. William Hampson heads the team and focuses on investor-state and commercial arbitration matters, with expertise in the oil and gas sectors.

Luciana Ricart and Thomas Francis are also Recommended Lawyers in this category.

Key client testimonials:

• 'The individuals in the Curtis team demonstrate a high level of professionalism and a strong willingness to work.'
• ‘The team has great commercial and litigation acumen, and can get great results for clients.’
• ‘William Hampson is a partner with great litigation instincts and very sound judgment. He is an asset in every dispute.'
• ‘The Curtis team is very experienced and vastly talented.’
• ‘The Curtis litigation team, led by William Hampson, is very highly responsive and understanding of our precise needs.'
• 'A very deep understanding of difficult and complex legal principles on state immunity.'
• ‘William Hampson is not only an excellent lawyer, but an individual who understands exactly what clients need and the particular sensitivities of business.’
• 'Deep specialisation, collaborative culture, and client-first mindset, which combine to make the practice truly unique. What sets the team apart is a blend of technical legal excellence and practical, business-oriented advice. The counsel consistently demonstrates a nuanced understanding of complex legal frameworks, while tailoring their guidance to align with our commercial objectives. Potential clients should know that this is a team built on depth and trust.'
• 'Stand out for their unmatched professionalism, strategic insight, and personal investment in our success. Unlike many firms where legal support can feel transactional, the partners and associates in this practice bring an excellent level of commitment and attentiveness.'

The full editorial is available here.