Duncan Speller

Duncan Speller is a partner in the firm's Litigation/Controversy Department, and a member of the International Arbitration Practice Group. He joined the firm in 2002. Mr. Speller is based in the London office, where he practices International Arbitration and English High Court Litigation.


Mr. Speller is an English barrister. He has represented clients in numerous institutional and ad hoc arbitrations, sited in both common and civil law jurisdictions, including England, New York, Hong Kong, Singapore, France, Switzerland, Sweden, Austria and Germany. Mr. Speller also has substantial experience of international commercial litigation in both the English Court of Appeal and in the Commercial and Chancery Divisions of the High Court. He has particular experience of litigation concerning aviation, oil and gas, insurance and reinsurance, telecommunications, banking and competition law issues.

Professional Activities

Mr. Speller was called to the Bar of England and Wales by Lincoln’s Inn in November 2001. Mr. Speller has taught commercial law, the conflict of laws and EU law at the University of Cambridge.


    • Successfully representing a North American company in defeating claims of over US $60 million in an ICC arbitration sited in London regarding a business venture in Africa.
    • Successfully representing a multinational company in defeating claims in excess of Euro 35 million in an arbitration sited in Munich under the DIS Rules.
    • Successfully representing an Asian airline in pursuing substantial claims under aircraft lease agreements in an LCIA arbitration sited in London.
    • Successfully representing the contractor in two parallel ICC arbitrations governed by English law and sited in Stockholm with an amount in excess of US$ 80 million arising out of a construction contract.
    • Successfully representing a North American company in a series of ad hoc arbitrations sited in London and Bermuda concerning insurance coverage disputes governed by New York law.
    • Successfully representing a Russian investment bank in an ICC arbitration in relation to an investment in the Russian oil industry.
    • Successfully representing a North American company in an ICC arbitration concerning contracts for the supply of capital goods for an oil field in Central Asia.
    • Successfully representing a hedge fund in pursuing claims in the English Commercial Court arising from a default under a Euro 350 million bond. The client obtained summary judgment in its favor with indemnity costs.
    • Successfully representing a North American company in a technically complex dispute in the Commercial Court in London arising out of a joint collaboration agreement.
    • Advising the shareholders in a telecommunications joint venture on their position in relation to concurrent proceedings in two Caribbean jurisdictions and two Swiss-sited arbitrations.
    • Advising a European oil company in relation to a number of disputes arising under Production Sharing Contracts concerning oil fields in India.


  • Featured in Who's Who Legal: Arbitration and named a leading arbitrator in the 20172021 editions of Who's Who Legal: Arbitration - Future Leaders—a guide profiling the foremost practitioners in the arbitration community. Mr. Speller was cited as being an “outstanding lawyer” who possesses a “super brain,” “a smart, hard-working and very impressive advocate,” "phenomenal; extremely effective and doing exceptionally well," with one source stating, "He has one of the most exceptional legal minds I have ever come across. He is, quite simply, brilliant. If you have a dispute, he should be your first choice."
  • Selected for inclusion in the 2020 and 2022 editions of The Best Lawyers in the United Kingdom for his work in international arbitration.
  • Listed as a leader in aviation in the 2011–2014 editions of The Legal 500 UK. Mr. Speller was cited for his vast experience with aviation disputes and recognized as a "key figure" of WilmerHale's top tier UK aviation team. He was also recommended for dispute resolution: international arbitration in the 2013, 2016 and 2018 editions.

Insights & News


  • Education

    • Inns of Court School of Law, 2001

      Wolfson Scholarship and Hardwick Entrance Award (Lincoln’s Inn, London)
    • BCL, University of Oxford, Magdalen College, 2000

      with Distinction Scholarship from British Academy for B.C.L.
    • BA, University of Cambridge, Robinson College, 1999

      with First Class Honours George Long Prize for Civil Law, University of Cambridge
  • Admissions

    • England and Wales, Barrister

  • Languages

    • French

    • Japanese