Three Crowns maintained its top position for International Arbitration in The Legal 500 – UK 2021 rankings. Constantine Partasides QC, Gaëtan Verhoosel, Reza Mohtashami QC, Carmen Martinez Lopez, Manish Aggarwal, Leilah Bruton, and Penny Martin are recognised individually, with Partasides and Verhoosel garnering “Hall of Fame” honours. In addition, the firm maintained a leading ranking in Public International Law.


In once again naming Three Crowns a top practice in International Arbitration, The Legal 500 underscored that the firm is “regularly sought out to act . . . in the largest and most complex and sensitive disputes across the globe” for both corporate and governmental clients in a wide variety of sectors, including energy, oil and gas, utilities, financial services, mining, and telecoms.

Three Crowns’ “dynamic team” is “consistently leading some of the most significant global commercial disputes,” with additional expertise in investor-State, post-M&A, and taxation disputes. As one client noted, the firm “provides a seamless experience for clients.”

Additionally, the firm is recognised with a leading ranking in Public International Law, with The Legal 500 lauding its “diverse and growing client base.”

“Retaining for another year our top-tier ranking for International Arbitration in The Legal 500 UK 2021 directory, and seeing the growing number of our lawyers that are now identified as leaders and future leaders in the field, is recognition for the efforts we make to maintain the standard of excellence in all that we do,” said Partasides. “Modern arbitration is a ‘team sport,’ and we are proud to have built for our clients a superlative team.”


Constantine Partasides QC

Partasides is an inaugural member of The Legal 500 UK “Hall of Fame” for International Arbitration. He is also a “Leading Individual” in Public International Law. Partasides has appeared as counsel in some of the largest commercial arbitrations of the past decades and his broad practice includes inter-State and investment treaty disputes. He has published extensively on international arbitration and international law.

Gaëtan Verhoosel

Verhoosel is also an inaugural member of the The Legal 500 UK “Hall of Fame” for International Arbitration. As one client noted to the publication, he is “succinct and clear with his advice and provides options with the pros and cons of each.” Verhoosel has served as advocate and as arbitrator in numerous commercial and investment treaty arbitrations where significant financial recoveries were at stake or novel legal issues raised.

Reza Mohtashami QC

Mohtashami, featured in the rankings again in 2021, has represented clients as counsel and advocate in more than 80 arbitrations conducted under a variety of arbitration rules in many different jurisdictions. He has particular expertise in disputes arising in emerging markets and is a highly sought-after specialist in the Middle East, with a focus on the telecoms, energy, and infrastructure sectors.

Carmen Martinez Lopez

Martinez Lopez also repeats in the rankings for 2021. A “Spanish and Latin America expert,” she has appeared as advocate in numerous investment treaty and commercial arbitrations, both under the rules of the major arbitral institutions and ad hoc, across a variety of jurisdictions.

Manish Aggarwal

Aggarwal is once again recognised for 2021 as a “Next Generation Partner” in both International Arbitration and Public International Law. As one client noted, he is “very meticulous and grasps concepts and details easily and we get comforted with his thoroughness in appreciating the facts and the context of situations.” Aggarwal, a dual-qualified English solicitor and Indian advocate, has extensive experience representing corporations and States in a broad range of sectors.

Leilah Bruton

Bruton is recognised as a “Rising Star” in International Arbitration for the first time in 2021. She has extensive experience representing corporations on the resolution of complex disputes involving investment treaties and contractual relationships, specialising in oil and gas disputes.

Penny Martin

Martin is also recognised for the first time as a “Rising Star” in International Arbitration. Her wide-ranging expertise includes international commercial and investment treaty arbitration, public international law, and international human rights law. She has a focus on the energy sector, as well as experience of intellectual property disputes.


Three Crowns is a firm committed to excellence in international arbitration and international law. Founded by practice leaders with decades of experience across many different international firms, it is recognised as one of the premier arbitration practices in the world. Its clients—including Fortune 500 companies and sovereign States—entrust the firm with their most important disputes.

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