LAWYER PROFILE
Jeffrey Sullivan KC

Jeffrey Sullivan KC

Global 2026

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Debevoise & Plimpton LLP
 Debevoise & Plimpton LLP

Ranked in 3 practice areas

International Arbitration

UK

4 years ranked

Energy & Natural Resources: Disputes

UK

3 years ranked

Arbitration (International)

Global Market Leaders

5 years ranked

Arbitration (International)

Europe-wide

2 years ranked

Chambers Review

Provided by Chambers

Chambers Global Guide

International Arbitration - UK

Band 1
Individual Editorial
Jeffrey Sullivan KC is co-chair of Debevoise's arbitration group in Europe. He is particularly known for his expert handling of claims brought under the ECT, which forms part of his extensive investor-state arbitration practice. He demonstrates strength across the energy and infrastructure sectors.
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Energy & Natural Resources: Disputes - UK

Band 2
Individual Editorial

Jeffrey Sullivan KC of Debevoise & Plimpston is a respected energy disputes lawyer with strong experience of handling claims in both the oil and gas and renewables sectors. He is highly adept at assisting with Energy Charter Treaty claims and the annulment of intra-EU investment treaties.

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Arbitration (International) - Global Market Leaders

Band 3
Individual Editorial

Jeffrey Sullivan KC is based in London and is widely recognised for his ability to lead arbitrations across a plethora of sectors and industries, most notably in energy and infrastructure. He also has a wealth of experience advising high profile international clients before major arbitral tribunals under ICSID, UNCITRAL and LCIA rules.

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Arbitration (International) - Europe-wide

Band 4
Individual Editorial

Jeffrey Sullivan KC is well regarded for his broad practice undertaking complex commercial and investor-state arbitrations. He has expertise in a range of matters related to energy and infrastructure.

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Strengths

Provided by Chambers

  • Jeff is always available, delivers straightforward practical advice and is great at handling clients.

    International ArbitrationChambers Global Guide

  • Jeffrey provides excellent support.

    International ArbitrationChambers Global Guide

  • Jefferey is extremely clear and sees any issues straight away.

    International ArbitrationChambers Global Guide

  • Jeffrey is an excellent operator with extensive experience, sensible judgement and measured advice.

    International ArbitrationChambers Global Guide

  • Jeffrey has an excellent technical skill set.

    International ArbitrationChambers Global Guide

  • Jeffrey is super impressive and a great guy.

    Energy & Natural Resources: DisputesChambers Global Guide

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    Mark D Johnson

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Europe-wide

Global Market Leaders

Latin America - International Counsel

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