Marie Leppard


Marie advises clients on all aspects of EU, UK and international competition law as well as the new UK National Security/European Foreign Direct Investment regimes.

Over the last few years, Marie was involved in a number of high-profile cross-border merger control investigations before  the European Commission and UK authorities and has acquired considerable experience in advising private equity houses and financial sponsors.

Marie has also worked on numerous high-profile cross-border cartel investigations before the European Commission, the CMA, the FCA, the PSR and the US Department of Justice, including advising a major investment bank on a number of financial services investigations, including FOREX, obtaining a competition law injunction against Google and successfully defended a generic company in two CMA’s investigations into price fixing of Prochlorperazine and other generic products.

Alongside her contentious practice, Marie has vast experience in providing clients with compliance framework and training as well as advising on the use of the latest technologies and artificial intelligence in internal audits, self-reporting and cartel investigations.

Before joining Euclid Law as a partner in November 2016, Marie worked at Clifford Chance’s antitrust practice (London and Paris). Prior to that, she worked at Sullivan & Cromwell (London).

Marie regularly advises clients in banking, finance services, private equity, biotech, energy, oil and gas, consumer goods as well as healthcare.

Marie was named the 2023 Competition Law Lawyer of the Year in the Women in Law Awards 2023 issue and has been recognised by Who’s Who Legal as a Competition Future Leader and Competition Expert since 2018. What clients have to say:

  •  “Marie Leppard is “an accomplished lawyer”, who is admired for her “excellent judgement” as well as her impressive ability to “quickly establish effective working relationships.”
  • “Marie Leppard is widely recommended by clients, who applaud her “humane, reassuring approach in combination with a brilliant understanding of competition law.”
  • “Marie is one of the most impressive competition lawyers of her generation.”
  • “She provides top-notch advice.”
  • “She is a great pleasure to work with.”

Recent experience includes advising:

  • Copart, Inc. on Phase 2 full clearance for its acquisition of Green Parts Specialist Holdings Ltd (Hills Motors) before the CMA.
  • Mastercard on settlement of the Payment System Regulator’s Chapter 1 investigation into prepaid cards in the UK.
  • Barclays in relation to the Libor and Forex investigations by the European Commission.
  • Refresco on Phase 1 clearance with remedies for its acquisition of Cott’s bottling activities before the CMA.
  • Unlockd in its litigation against Google for abusing its dominant position by removing Unlockd’s apps from the Google Play Store ecosystem and denying access to its ad server Admob.
  • Royal Dutch Shell in relation to the sale of its Harburg refinery to Nynas AB
  • Royal Dutch Shell in relation to the acquisition of Repsol’s LNG assets
  • a generic pharmaceutical client in relation to the CMA’s excessive pricing and anti-competitive conduct investigation
  • an immunity applicant in the European truck cartel as well as the global marine hose and the hydrogen peroxide cartels.
  • European Commission together with Europe Economics, appointed to assist and advise DG Comp in its market study in relation to loan syndication in Europe.
  • Private Equity Houses on mergers, acquisitions and joint ventures in the UK and Europe.
  • Brands in relation to their distribution strategies in Europe

Includes matters handled at Euclid or prior to joining the firm.


LLM, University College of London
LLB, Law and French, University of Surrey


England & Wales
Brussels (B list)


English, French and Spanish

Recent Publications and Speaking Engagements

Marie has spoken at a number of events in the last few years, including the European Competition Law Association Conference and a number of Antitrust Compliance conferences on competition law.

Marie is the co-author of a practical guide on the ‘Day-to-Day Competition Law for Businesses’ and has published various articles which can be found here

Contact Details

+44 20 3816 3011



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