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Practice Summary

Jeffery Onions undertakes a wide range of complex commercial and company law disputes work both as an advocate and in an advisory context. He has particular expertise in banking and finance, company and insolvency, commercial litigation, civil fraud, energy/oil and gas, insurance and reinsurance, shareholder disputes and sport/media-related cases. He is equally at home in arbitration proceedings, as he is in High Court litigation. He also accepts appointments as an arbitrator and expert.

‘Extremely client friendly and quick-minded.’ Legal 500 2018-2019 – Energy

‘A class act on his feet, very good on the detail and a super cross-examiner.’ Legal 500 2018-2019 – Commercial Litigation

"He is incredibly hands-on and user-friendly for a very senior counsel, and his ability to synthesise arguments and present them effectively is very impressive." "He is a very thorough, very courteous and utterly reliable advocate." Chambers and Partners UK 2019 – Energy and Natural Resources

"A real authority with years of experience; there's nothing he doesn't know. In court he has real presence and is a great cross-examiner." Chambers and Partners UK 2019 – Commercial Dispute Resolution

"Has formidable technical knowledge, and is a demon cross-examiner." "He rolls up his sleeves and gets completely stuck in." Chambers and Partners UK 2018 - Commercial Dispute Resolution

"He rolls up his sleeves and gets completely stuck in - he is consummately flexible and so immersed in his subject." "He is steeped in the oil and gas industry." "Phenomenally intelligent and very client-friendly."  Chambers and Partners UK 2018 - Energy and Natural Resources

"He has formidable techincal knowledge and is a demon cross-examiner." "He's fantastically hands-on for such a senior leading counsel." Chambers and Partners UK 2017 - Commercial Dispute Resolution

"Phenomenally intelligent yet client-friendly." "He's a very good cross examiner and very hard-working." Chambers UK 2017 - Energy & Natural Resources

"Has formidable technical knowledge and is a demon cross-examiner". "A heavyweight advocate with real clarity of argument and courtroom presence". Chambers UK 2016

Recent cases include:

  • Acting in an ongoing confidential dispute involving a major infrastructure provider in relation to issues arising with the entities using the infrastructure.  
  • Acting in a substantial arbitration involving private equity funds and the purchase of telecom towers in Africa.
  • Advising in relation to a major infrastructure project involving the construction of a major road and the contractual terms required in relation to indemnities.
  • Acting in a substantial arbitration relating to wind farms in the North Sea.
  • Acting in a substantial arbitration relating to oil and gas exploration in Libya.
  • Acting in and advising on disputes relating to the sale and purchase of substantial infrastructure assets in the North Sea, raising issues as to in particular, pre-emption rights.
  • Acting in a substantial dispute involving a major insurance company and its service provider regarding termination and compensation rights.
  • Acting in substantial dispute relating to the production of and the intellectual property rights in green indices.

Significant and reported cases in specific practice areas are detailed in the full CV.