Jeffrey Sullivan KC

Ranked in 4 Practice Areas

Band 2

International Arbitration

3 Years Ranked

Band 3

Energy & Natural Resources: Disputes

2 Years Ranked

Band 4

Arbitration (International)

Global Market Leaders

4 Years Ranked

Band 5

Arbitration (International)

Europe-wide

1 Years Ranked

Ranked in Guides

UK 2025

Europe 2025

Chambers Review

Provided by Chambers

Chambers Global Guide

International Arbitration - UK

Band 2

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 3

Individual Editorial

Jeffrey Sullivan KC of Debevoise & Plimpton is a respected energy disputes lawyer with strong experience of handling claims in both the oil and gas and renewables sector. 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 4

Individual Editorial

London-based Jeffrey Sullivan KC is a leading practitioner possessing longstanding experience in representing an impressive roster of international clients before major arbitral tribunals under ICSID, UNCITRAL and LCIA rules. Sullivan has an established reputation for leading arbitrations across a plethora of sectors and industries, notably energy and infrastructure.

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Arbitration (International) - Europe-wide

Band 5

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

Jeffrey Sullivan is a powerhouse of investor-state arbitration.

International Arbitration respondent
Chambers Global Guide

He is extremely well connected and his written work and advocacy is of the highest quality. He is an expert and is really well established across the market. He is an exceptional lawyer.

International Arbitration respondent
Chambers Global Guide

Jeffrey Sullivan is an expert in renewable energy disputes. You can give him really complex, difficult, knotty stuff.

Energy & Natural Resources: Disputes respondent
Chambers Global Guide

Jeffrey is brilliant, pragmatic and a great team leader. He is a pleasure to work with.

Arbitration (International) respondent
Chambers Global Guide

Jeffrey is a reliable professional with deep expertise in energy law matters.

Arbitration (International) respondent
Chambers Global Guide

His written work and advocacy is of the highest quality; he is very easy to deal with, professional, works really hard and is an exceptional lawyer.