JUNIOR PROFILE

Thomas Sebastian

Global 2026

 Monckton Chambers

Ranked in 2 practice areas

Public International Law: The English Bar

Global Market Leaders

Competition Law

UK

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Chambers Review

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Chambers Global Guide

Public International Law: The English Bar - Global Market Leaders

Band 2
Individual Editorial

Thomas Sebastian is highly regarded for his investment treaty and WTO work. He has acted in treaty disputes involving Cuba, Colombia, Thailand, India and South Africa, and has also advised the UK government on Brexit-related international law issues.

Strengths

He is a straight shooter. He is very direct, honest and thorough.

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Competition Law - UK

Band 3
Individual Editorial

Thomas Sebastian is well known for his handling of major competition cases for clients from the technology sector. He defends clients in investigations into possible abuse of dominance and cartels, and also has experience acting for claimants in collective proceedings.

Strengths

He's extremely intelligent and unfailingly calm under pressure. He's a real diplomat, excellent at liaising with clients and adept at plotting a path through difficult legal challenges.

Thomas is very, very good on the detail. For complex matters he's really excellent - he doesn't fluff over any details and gets right down to the nitty gritty.

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Ranked Barristers at Monckton Chambers (48)

Global Market Leaders

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    Drew Holiner

    International Arbitration - The English Bar

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  • Profile image of Francis Hornyold-Strickland
    Francis Hornyold-Strickland

    International Arbitration - The English Bar

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  • Profile image of George Hilton
    George Hilton

    International Arbitration - The English Bar

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  • Profile image of Thomas Sebastian
    Thomas Sebastian

    Public International Law: The English Bar

    View profile

UK

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