Marc acts for financial institutions, public and private companies, states and state-entities, and high net worth individuals in complex commercial and financial disputes. His practice areas include banking and financial services litigation, securities litigation, company and shareholder disputes, professional negligence, insurance disputes, contentious insolvency, fraud claims and asset tracing.

Marc has been the lead partner in a number of ground-breaking cases, including:

  • Robertson v Person Unknown (in which the High Court treated Bitcoin as legal property and the claimant recovered £1million of bitcoin);
  • the Golden Belt bond litigation (the only case in which the High Court has found that an arranging bank owed a duty of care to the secondary bond market); and
  • the Standard & Poor’s litigation (the only occasion on which a rating agency has been sued in the UK for negligently rating complex derivatives).


A cross-section of Marc’s experience includes:

  • Acting for Kestrel Coal Midco Pty in its defence of claims brought by Quartz Assets LLC and Quartz Assets PTE Ltd concerning the mezzanine financing of Kestrel’s $2 billion purchase of Rio Tinto’s Kestrel coal mine in Australia.
  • Successfully recovering £1 million worth of bitcoin for the claimant in Robertson v Persons Unknown, in which the High Court considered whether crypto-currencies are legal property.
  • Acting for US investors in claims for US$650m concerning a failed Islamic bond (sukuk), in which the High Court found in favour of the claimants and held for the first time that an arranging bank owed a duty of care to the secondary bond market.
  • Acting for European investors in the first UK claim against a rating agency and major bank seeking over £100 million in damages for alleged fraudulent and negligent rating and marketing of complex financial products.
  • Acting for mezzanine lenders resisting the non-consensual Euro 519 million restructuring of a leading automotive parts manufacturer – the Stabilus Group – and pursuing claims against the senior lenders and security trustee.
  • Acting for assureds in insurance disputes, including denial of coverage claims for an international provider of audit services, an international telecommunications company and a major IT services provider.
  • Acting on a Privy Council appeal for a BVI company against former directors on the question whether the BVI’s Business Companies Act 2004 permits a company’s constitution to grant its directors a complete indemnity for their liability to the company for breach of their duty of care and skill.
  • In the Court of Appeal acting for multiple off-shore entities resisting the jurisdiction of the Family Division of the High Court to join the overseas entities in divorce proceedings.


Marc is recommended in The Legal 500, where he has been described as a “smart and commercially astute” litigator who is “very popular with clients”. He was the lead partner representing claimants in a dispute recognised as one of the Top 20 cases of 2017 by The Lawyer.


Marc read law as an undergraduate and postgraduate at Oxford University and qualified as a solicitor at Ashurst in 1999. He joined Stewarts in December 2009 and has been a partner since May 2013.

Media and public speaking

Marc has written for and been quoted in various publications, including City AM, Thomson Reuters Practical Law, Bloomberg Tax, Financier Worldwide, The Law Society Gazette, Competition Law Insight and Supply Management.

The joint report of the Law Society and Tech London Advocates Blockchain Legal & Regulatory Group – “Blockchain: Legal & Regulatory Guidance” – Marc produced the section on decentralised autonomous organisations (DAOs) at pages 39-41.

“Life Moves Pretty Fast”: a decade on from bitcoin, English law confronts cryptoassets – Page 55 of “Juriste” – Article on recent developments in English law regarding digital assets.

Marc’s recent speaking appointments include:

  • Cybercrime Practitioners Association: Bitcoins and Virtual Currencies – Legal Developments in Injunctions and Asset Preservation (January 2020)
  • Ethereum London (#ETHLDN): Robertson v Persons Unknown and the recent Legal Statement on Cryptoassets and Smart Contracts (January 2020)
  • UIA annual congress in Luxembourg: Digital Assets and Private International Law (November 2019)


Accreditations and Memberships

  • Union Internationale des Avocats
  • London Solicitors Litigation Association
  • Association Internationale de Jeunes Avocats