Boris Bronfentrinker is a partner in Willkie’s Litigation and Antitrust & Competition practices in London. Boris is a solicitor advocate practicing in complex commercial litigation, with particular experience in competition litigation. He has represented clients, both as claimants and defendants, in leading and high profile cases in both the High Court of England & Wales and the Competition Appeal Tribunal, as well as coordinating competition litigation proceedings in other jurisdictions globally. Regularly acting for both claimants and defendants gives Boris a unique perspective and insight into the conduct of competition disputes from both sides. Boris is experienced in not only litigating cases to judgment but also resolving claims through alternative dispute resolution, such as mediation.

Boris also has experience of representing clients in the defence of investigations by the European Commission and national competition authorities, including sector inquiries, as well as managing internal investigations into competition law and bribery/corruption issues.

Who’s Who Legal named Boris as a Global Elite – Thought Leader in Competition: Plaintiff and as one of their inaugural Thought Leaders – Competition, placing him among the very best globally in the area of competition litigation, as judged by his peers, corporate counsel and market sources. Who’s Who Legal states that Boris is "a very well-known name’ in Europe’s competition market, with ‘impressive advocacy skills’ and ‘a strong understanding of economic arguments’ which ensures that ‘novel approaches do not scare him." He is “a lawyer absolutely at the top of his game,” and is widely praised for his “instinctive and immediate analysis of litigation issues and tactics,” noting that “what Boris doesn’t know isn’t worth knowing.” Boris is recognised and highly ranked by Chambers UK, Chambers Europe and Chambers Global for Competition Law, as well as being ranked a leading individual in Competition Litigation by The Legal 500 and by Best Lawyers for Competition Law.

Boris was recognised by The Lawyer as one of only five partners to appear on four or more of the Top 20 Disputes Cases in the UK over the past 10 years. He was also named in the inaugural 2024 Lawdragon 500 Global Plaintiff Lawyers list as a standout lawyer for Competition Litigation, inc. Claimant. In 2016, Boris was featured in The Lawyer’s ‘Hot 100’ list and Global Competition Review’s ‘40 under 40’ guide.

A native English speaker, Boris is also fluent in Russian.


Prior to joining Willkie, Boris was a partner and co-head of the UK Antitrust and Competition Litigation practice at Quinn Emanuel. Before that Boris was a partner at Hausfeld & Co UK LLP, and worked as an associate at Freshfields Bruckhaus Deringer LLP and Freehills LLP (now Herbert Smith Freehills).

  • Recognised in Who’s Who Legal: Thought Leader (Competition – Plaintiff) 2024.
  • Global Competition Review Awards 2021, Litigation of the Year – Non-Cartel Prosecution.
  • Legal Business Awards 2021, Highly Commended for Commercial Litigation Team of the Year.
  • The Lawyer Awards 2020, Competition and Regulatory Team of the Year.
  • British Legal Awards 2019, Litigation and Dispute Resolution Team of the Year.
  • Legal Week 2019, Competition Litigation Team of the Year.
  • Global Competition Review Awards 2020 and 2021, nominated for the Litigator of the Year award
  • Ranked by Chambers Global 2024, Chambers Europe 2024 and Chambers UK 2024 for UK Competition Law: Litigation and Competition Law: Private Enforcement: Claimant. 
  • Recognised as a Leading Individual by The Legal 500 UK 2024.
  • Recognised by Euromoney’s Expert Guide.
  • Recognised in Global Competition Review’s “40 under 40” list in 2016 for best competition lawyers globally.
  • Named a Rising Star in Litigation by Legal Week in 2016.
  • Named a Rising Star in the 2016 Financial News “40 under 40” Awards, in the category of Legal Services.
  • Named to "The Hot 100" List for Litigation by The Lawyer in 2016.
  • Trained Mediator, Centre for Effective Dispute Resolution (CEDR)
  • Boris is a regular conference speaker on the subject of private enforcement of competition law and third party funding.

Boris has advised on the following selected significant matters*:

Antitrust and Competition Litigation

  • Advising and representing Daimler AG Mercedes-Benz Cars UK Limited in defence of a multitude of cartel damages claims (both individual claims and proposed collective actions) arising from the European Commission’s decision in respect of a cartel in relation to trucks.
  • Advising and representing Daimler AG in the pursuit of cartel claims against various suppliers of automotive part and services, including the co-ordination of claims in the UK, Germany and United States. Representation covered proceedings in the English High Court and New Jersey State Court, against shipping companies providing vehicle carriage services.
  • Advising and representing Walter Merricks CBE in the first collective action to be certified in the United Kingdom, a claim on behalf of 46 million consumers seeking billions in damages against Mastercard. The case involved success on the issue of class certification before the Court of Appeal and the United Kingdom Supreme Court.
  • Representing Stellantis N.V. (formerly Fiat Chrysler) in cartel damages claims against supplier of automotive parts, including the co-ordination of claims in the United Kingdom and the United States, covering claims in respect of wire harness and automotive bearings.
  • Advising and representing a financial services company in respect of a potential dispute with a payment card provider.
  • Advising and representing major international asset managers such as Allianz Global Investors, PIMCO, Brevan Howard and major pension funds such as PFA Pension of Denmark and the Swedish State Pension funders (AP1 to AP4), in claims against the major banks for manipulation of foreign exchange markets.
  • Representing a group of European bedding manufacturers in claims for damages in the English High Court for losses arising from the polyurethane foam cartel.
  • Representing Deutsche Bahn AG in a claim for damages in the Netherlands for losses arising from the pre-stressing steel cartel.
  • Representing Dunlop Oil & Marine Limited in defence of investigations by the European Commission, the United States Department of Justice, the Japanese Fair Trade Commission, the Korean Fair Trade Commission and the Australian Competition & Consumers Commission in respect of the marine hose cartel, and defence of the follow-on damages litigation.
  • Representing SGL Carbon SE in defence of a damages claim brought by purchasers of carbon brushes in the Competition Appeal Tribunal following on from the European Commission decision in respect of the mechanical and electrical carbon cartel.
  • Representing Koninklijke Philips and three other patentees in defence of a claim by SanDisk alleging abuse of dominance. This case is one of the leading English judgments on the interpretation of the Judgments Regulation.

Commercial Litigation

  • Advising and representing the Palladium Group (owned by the Matutes family) in claims in the English Commercial Court of over €500 million against Deutsche Bank for the miss-selling of complex foreign exchange linked derivates.
  • Representing Raga Investments in an arbitration against SCM Capital Management (owned by Ukrainian oligarch Rinat Akhmentov) securing judgment for over $800m, and coordinating freezing injunctions in the Cyprus courts, in respect of ownership of the national telecommunications company of Ukraine.
  • Representing FMC Corporation in claims for breach of contract in the English High Court against Unilever.


  • Advising and representing a multinational in relation to the European Commission’s E-commerce sector inquiry.
  • Representing Hays plc in defence of an Office of Fair Trading investigation in respect of anti-competitive conduct in the construction recruitment sector, including an appeal to the Competition Appeal Tribunal against the penalty that resulted in the largest penalty reduction to that date.
  • Representing Visa Europe in defence of investigations by European competition authorities in respect of alleged anti-competitive practices relating to the setting of multilateral interchange fees.
  • Representing Wyeth in the European Commission’s pharmaceutical sector inquiry.
  • Advising MTN Group in respect of an internal investigation conducted by Lord Hoffmann in to allegations of bribery and corruption made by Turkcell relating to the award of a mobile telephone licence in Iran, including supporting the defence of proceedings brought against MTN in the United States by Turkcell.

*Boris advised on some of these matters prior to joining Willkie.



King's College London, Post Graduate Diploma, 2007 University of Sydney, Bachelor of Laws, 1999 University of Sydney, Bachelor of Economics, 1997

Bar Admissions

England & Wales New South Wales