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Gwen Ballin-Reeler, Managing Associate, Dispute Resolution

Gwen Ballin‑Reeler

Of Counsel

Personal Profile

Gwen is Of Counsel in the Competition group in the Innovation Department.

She is currently advising Justin Le Patourel,  the class representative in a  £600 million opt-out collective action in the Competition Appeal Tribunal against British Telecom.  Gwen has extensive experience of advising clients in competition damages claims in the High Court, Competition Appeal Tribunal and arbitrations, including a number of interchange fee claims.

Prior to joining Mishcon de Reya, Gwen trained in Linklaters' London and Brussels offices.  She has a broad competition law background, gained from working on high profile EU Commission investigations and transactional matters.

Key Experience

Competition Litigation

  • Advising Justin Le Patourel in his £600 million opt-out collective action against BT alleging an abuse of BT's dominant position in landline services markets.
  • Advising Microsoft in relation to its stand-alone damages claims in the UK in relation to losses suffered as a result of price fixing of lithium-ion batteries
  • Advising numerous clients on their interchange fee claims against Visa and Mastercard in the High Court and the Competition Appeal Tribunal


  • Advising an individual in relation to the CMA's investigation into bid-rigging in the construction, design and fit out sector.
  • Acting for a large investment bank in relation to the EU investigation into the Credit Default Swaps market
  • Advising a business in in relation to complex pricing issues and potential breaches of Article 102 of the Treaty on the Functioning of the European Union
  • Advising property companies in relation to anticompetitive land agreements
  • Advising a supermarket in its CMA complaint regarding the anticompetitive behaviours of its competitors

Mergers and Markets

  • Advising on procurement issues for an international corporate within the transport sector.
  • Advising a large retail business in relation to national and localised competition aspects of a UK Phase I merger
  • Advising on Phase I merger remedies in the retail sector for a large UK business
  • Advising a large food sector business on the competition aspects of the potential acquisition of a large competitor

Career History

Managing Associate, Mishcon de Reya LLP
Associate, Mishcon de Reya LLP
Trainee, Linklaters
PGDip (EU Competition Law), King's College London
Legal Practice Course, The University of Law (Moorgate)
Graduate Diploma in Law, The University of Law (Bloomsbury) 
BA (Hons) (History), Royal Holloway University

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