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Mavroghenis, Stephen

Stephen C. Mavroghenis

Direct Tel: +32 2 416 5003
Tel: +32 2 416 5000 Fax: +32 2 416 5100

Stephen Mavroghenis is a partner in Quinn Emanuel’s Brussels office. He was previously head of Shearman & Sterling’s Brussels office and Co-head of its Global Antitrust Group. His practice focuses on competition law and policy.

Stephen’s practice focuses on EU and UK competition law, in addition to EU regulatory and intellectual property law. Stephen has extensive experience in the aviation, chemicals, energy, high-tech and information technology, pharmaceuticals and medical devices, manufacturing, and media and entertainment industries. He regularly appears in proceedings before the European Commission and the European Courts in Luxembourg. He also appears before the national competition authorities of several member states.

Stephen regularly advises multinational corporations on international mergers, acquisitions, joint ventures and corporate takeovers and defends clients against allegations of cartel participation and abuses of dominance, including issues relating to refusals to deal/license, intellectual property rights, rebates, predatory and excessive pricing. Stephen also regularly counsels clients on a broad variety of business practices including licensing and supply agreements, distribution, agency and the establishment and maintenance of compliance programs.

Stephen has published widely on competition issues and is a contributor to multiple legal publications, and is a frequent speaker on competition law and policy.

Stephen is consistently ranked among leading antitrust specialists in peer review rankings and is named as a leading competition lawyer by Global Competition Review, Chambers, Legal 500, and the International Who’s Who of Competition Lawyers. Stephen was named both a Who’s Who Legal Thought Leader – Competition (one of only a handful in Brussels) and a Who’s Who Legal Competition Future Leader – Partners. Who’s Who Legal noted that Stephen “is highlighted by sources as a “bright, active practitioner with deep and impressive understanding of the clients’ businesses and needs”. He particularly excels in high-profile cross-border merger cases.” Chambers Europe reports that clients state, “he blends an understanding of the needs of the business with what he knows the regulators want to see," adding that "he is extremely persuasive and is willing to dig in where necessary, which leads to the best possible results." Another interviewee noted that Stephen “sees the bigger picture and how this matter can impact our business going forward. Furthermore an interviewee said, Stephen  defends companies in global cartel or abuse of dominance investigations carried out both by the EC and by competition regulators in other jurisdictions. "In terms of substance, he is really good." "He is very easy to work with because of his intelligence, his ability to understand complex situations and his ability to know what is important and what is not." In 2012 Stephen was named as one of the Global Competition Review’s “40 under 40” of the world’s brightest young antitrust lawyers and has been recognized by Chambers Global as ‘one of the best lawyers of the younger generation’.

  • Qualcomm Incorporated
  • Viacom and Paramount Pictures
  • Piraeus Bank
  • Huntsman
  • Textron
  • Syniverse
  • Société Générale
  • Hellenic Republic Asset Development Fund
  • Hilton Worldwide, Inc.
  • Caterpillar
  • Arch Chemicals
  • Nestlé
  • Merck & Co
  • Schering-Plough Corp.
  • Ingersoll Rand
  • Pfizer Pharmaceutical Company
  • ICI
  • Advised the American Banking Association in relation to the merger and conditional clearance of the proposed acquisition of IHS Markit by S&P Global.
  • StubHub/viagago. Successfully advised StubHub in relation to the Phase II Competition and Markets Authority inquiry into its acquisition by viagogo. EBay/viagogo.
  • Successfully advised EBay before the Competition and Markets Authority and, together with co-counsel, the Spanish National Markets and Competition Commission, in relation to the sale of its secondary ticketing business, StubHub, Inc.
  • Advised investor group in relation to the rescue and rescue and restructuring of HSH/Nordbank.
  • Qualcomm/NXP. Advised Qualcomm Incorporated in the Phase II investigation of its $47 billion acquisition of NXP Semiconductors N.V. both in the EU and rest of the world. (2018)
  • StateGrid/Hellenic Republic. Advised State Grid in its acquisition of joint control of the Greek Independent Power Transmission Operator (IPTO) (2017).
  • Major Asian manufacturing company. Representing in the European Commission’s current cartel capacitors investigation (ongoing).
  • Viacom and Paramount Pictures. Advised Viacom and Paramount Pictures in the EU’s Pay-TV investigation of provisions in licensing agreements between the major US film studios and the largest European pay-TV broadcasters.   We successfully reached early resolution of the matter for Viacom and Paramount with the European Commission (2016).
  • Piraeus Bank. Advised on the State aid aspects of its EUR 4.9 billion restructuring and recapitalization (2015).
  • Eurobank. Advised on the State aid aspects of its EUR 2.04 billion restructuring and its recapitalisation (2015).
  • Huntsman/Rockwood. Advised Huntsman in the Phase II Commission review of its USD 1 billion acquisition of Rockwoods titanium dioxide business. The acquisition was cleared with limited remedies (2014).
  • Textron/Beechcraft. Advised Textron (Cessna) regarding multiple worldwide filings in its acquisition of Beechcraft valued at USD 1.5 billion (2014).
  • Syniverse/MACH. Advised Syniverse in the Phase II Commission review of its EUR 550m acquisition of MACH. The acquisition was cleared with limited conditions (2013).
  • Société Générale/Piraeus Bank. Advised Société Générale on sale of its Greek subsidiary, Geniki Bank to Piraeus Bank (2012).
  • Privatisation of the Public Power Corporation (“PPC”). Counselling the Hellenic Republic Asset Development Fund in the framework of PPC’s privatisation (2012).
  • Hilton Worldwide, Inc. Defended Hilton in the Swedish competition authority’s investigation of alleged cartel activity in the hotel industry. Hilton was exonerated of all allegations (2012).
  • Caterpillar Inc./Bucyrus International Inc. Representing Caterpillar Inc. in connection with the company's USD 8.6 billion acquisition of Bucyrus International (2011).
  • Caterpillar Inc./MWM. Advised Caterpillar in obtaining an unconditional Phase II merger clearance for its USD 800 million acquisition of MWM Holdings GmBH (2011).
  • Lonza/Arch Chemicals. Representing Arch Chemicals before the UK, French and German competition authorities in connection with Lonza’s USD1.4 billion acquisition of all outstanding shares of Arch (2011).
  • Novartis/Alcon. Representing Nestlé in its USD 39 billion disposal of its majority interest in Alcon to Novartis (2010).
  • Major Originator Pharma Company. Advising an originator pharmaceutical company in relation to abusive patent strategy adopted by a competitor revolving around various patenting practices and strategies (2010).
  • Merck & Co. Representing Merck & Co in the European Commission Pharmaceutical Sector Inquiry (2010).
  • European Federation Of Pharmaceutical Industries And Associations (EFPIA). Assisting EFPIA in challenging the findings set out in the Commission’s Preliminary Report in the Pharmaceutical Sector Inquiry, in particular as regards the IP-regulatory interface and the impact of the IP regulatory aspects on the antitrust assessment (2010).
  • Schering-Plough Corp. (now Merck & Co, Inc). Representing Schering-Plough with regard to the European Commission’s Article 102 TFEU investigation into alleged misuse of patents to exclude potential competition in the area of chronic obstructive pulmonary disease (COPD) drugs (2010).
  • Schering-Plough Corp. (now Merck & Co, Inc). Representing Schering-Plough in its USD 41 billion merger with Merck & Co (2009).
  • Ingersoll Rand. Represented Ingersoll Rand before the European Commission regarding the acquisition of Trane (2008).
  • Schering-Plough Corp. (now Merck & Co, Inc). Represented Schering-Plough before the European Commission regarding the divestment of animal health assets to Pfizer (2008).
  • Schering-Plough Corp. (now Merck & Co, Inc). Represented Schering-Plough regarding its USD 11 billion acquisition of Organon BioSciences (2007-2008).
  • Hilton Worldwide, Inc. Counsel to Hilton on worldwide antitrust issues (2007 to present).
  • Pfizer Consumer Health. Advising Pfizer Pharmaceutical Company (Pfizer) in relation to the design and implementation of remedies in the context of the sale of Pfizer’s consumer health business to Johnson & Johnson (2006).
  • European Liner Affairs Association. Represented the world’s liner shipping industry in the Commission’s review and eventual termination of the Liner Conference Block Exemption, the adoption of Guidelines and the extension of the Liner Consortia Block Exemption (2004).
  • ICI. Assisted in advising ICI in the European Commission’s methacrylates cartel investigation and preparation of the appeal to the General Court (2004).
  • A major Hollywood studio. Advised a major Hollywood studio in its objections to the proposed Newscorp/ Telepiu merger (2003).
  • A major Hollywood studio. Advised a major Hollywood studio in the European Commission’s investigation of most favoured nation clauses found in the contracts of Hollywood film studios with a number of pay television companies in the European Union (2002 to 2004).
  • The College of Law
    (Legal Practice Course, 1996)
  • University College London
    (LL.B., with honours, 1994)
  • Solicitor, England & Wales
  • Advocaat (Brussels)
  • European Commission
  • UK Office of Fair Trade
  • UK Competition Commission
  • European General Court (EGC)
  • European Court of Justice
  • Ranked by Legal 500 EMEA in Belgium for Competition, 2019-2020, 2024
  • Ranked by Chambers Europe in Belgium for Competition, 2018-2021, 2023-2024
  • Ranked in Competition and Antitrust Law by The Best Lawyers in Belgium, 2023
  • Ranked by Who’s Who Legal’s, Thought Leaders for Competition 2018-2021
  • Ranked by Euromoney Expert Guides for Competition and Antitrust, 2018-2020
  • Ranked by Chambers Global in Belgium for Competition/European Law, 2017-2020
  • Recognized by The Best Lawyers in Belgium (2019 Edition)
  • Who’s Who Legal describes Stephen as “Stephen Mavroghenis of Quinn Emanuel Urquhart & Sullivan is highlighted by sources as a “bright, active practitioner with deep and impressive understanding of the clients’ businesses and needs”. He particularly excels in high-profile cross-border merger cases.”


  • Firm memorandum: EU Competition Law Development: Interim Injunctive Relief Back on the Menu
  • “Aid in the Banking Sector”, EU State Aid Control: Law and Economics, Wolters Kluwer (December 2016).
  • “EU Cartels & Leniency.” The EMEA Antitrust Review 2017, Global Competition Review, Co-author.
  • “The EU General Court annuls the Commission’s decision fining a number of cargo airlines for a price fixing cartel (Airfreight Cartel)”, Concurrences (January 2016), Co-author.
  • “EU Cartels & Leniency.” The European Antitrust Review 2016, Global Competition Review. Co-author.
  • “EU Cartels & Leniency.” The European Antitrust Review 2015, Global Competition Review. Co-author.
  • “Merger Remedies: An overview of EU and national case law.” e-Competitions, Antitrust Case Law Bulletin (May 2014). Co-author.
  • “Margrethe Vestager: The new EU competition Commissioner” CompLaw 360 (October 2014), Co-author.
  • “Takeaways from appeal of UK hotel bookings settlement” CompLaw 360 (October 2014), Co-author.
  • “Can EU states do whatever they want to foreign takeovers?” CompLaw 360 (September 2014), Co-author.
  • “The EU General Court gets a rap in its knuckles”, in Law360, Co-author (2014).
  • “EU Cartels & Leniency.” The European Antitrust Review 2014, Global Competition Review. Co-author.
  • “What is the legal basis of the EU cap of bankers’ bonuses?”, in City AM, London (2013).
  • “European Union Competition and Cartel Leniency.” Practical Law Multi-Jurisdictional Guide 2012, Competition and Cartel Leniency, PLC.
  • “Recent Developments in EU Merger Control 2012.” Journal of European Competition Law & Practice. Co-author.
  • “Recent Developments in EU Merger Control 2011.” Journal of European Competition Law & Practice (November 2010). Co-author.
  • “Public Funding of Broadband Services.” Global Competition Review—The European Antitrust Review 2007 (September 2006). Co-author.
  • “Predatory Pricing.” Global Competition Law Centre (2005). Co-author.
  • “Rescue & Restructuring Aid: A Brief Assessment of the Principal Provisions of the Guidelines.” European State Aid Law Quarterly (2003). Co-author.
  • “European Commission Consults on Technological Transfer Proposals.” European Regulatory Affairs News (2003).
  • “EU State Aid Overview.” Global Competition Review—The European Antitrust Review 2004. Co-author.


  • EU State aid Control: Law and Economics, Banking Sector. Wolters Kluwer Law & Business (2015). Co-Author.
  • The EC State Aid Regime—Distortive Effects of State Aid on Competition and Trade, the Market Investor Test. Cameron May (2006). Co-Author.

Speaking Engagements:

  • Panellist “Antitrust and Economic Regulatory Compliance: Hot Issues and New Trends in the EU, Japan, and Korea”, Legal Plus Japan: 8th Annual International Arbitration & Corporate Crime Summit (1 December 2022)
  • "Through the Looking Glass", Legal Plus South Korea: 9th Annual International Arbitration & Corporate Crime Summit (15 November 2022)
  • “Merger control assessment in the digital sector & Foreign direct investment”, Nomiki Bibliohtiki 5th International Conference (7 October 2021)
  • “The Rise of Global Mega-Firms: Lessons from the Aftermath of Siemens/Alstom”, Informa Connect Merger Control Digital Conference (13 October 2020)
  • “Data Collection, Protection, Sharing & Competition”, Nomiki Bibliohtiki 4th Annual Competition Law Conference (9 October 2020)
  • “Due process in competition proceedings: evolving standards”, IBA Annual Conference, Seoul (22-27 September 2019)
  • “Hipster Antitrust: Altering the Objectives of Antitrust Enforcement, Including Fairness, Privacy, and Public Interest?”, Wolters Kluwer & Legal Plus 6th Annual International Arbitration, Regulatory & Competition Law Global Summit (12 September 2019)
  • “Hipster Antitrust: Why Isn’t Consumer Welfare Enough?”, Nomiki Bibliohtiki 3rd Annual Competition Law Conference (10 May 2019)
  • “Advising on Cartel Enforcement in Asia”, Wolters Kluwer & Legal Plus 6th Annual International Arbitration, Regulatory & Competition Law Global Summit (6 September 2018)
  • “EC Cartel Enforcement Updates and Trends”, Nomiki Bibliohtiki 2nd Annual Competition Law Conference (16 March 2018)
  • “Cartel Settlements” and “Q&A Clinic”, IBC Legal Advanced EU Competition Law Conference (Brussels, November 2016).
  • “Regulation of platforms and the digital single market” (panelist), IBC Legal Competition Law and Regulation in the Telecoms, Media and Technology Sector Conference (Brussels, October 2016).
  • “Cartels – International problems and issues” and “Regional enforcement updates – Ask the experts – China, India, HK, EU Q&A (panel), Kluwer 2nd Annual Global Competition Law Forum (Shanghai, July 2016).
  • “Process, privilege and procedure: A guide to navigating new approaches to the EC process issues (panel”, GCR Live 8 Annual Brussels conference: The bigger picture (Brussels, July 2016).
  • “Advice in investigations – Japan, US and Asia focus”, Kluwer 2 Annual Japan Global Competition Law Forum (Tokyo, June 2016).
  • Chair of the Kluwer 5 Annual Global Competition Law Summit (Hong Kong, April 2016).
  • “Minority shareholders: Update on proposals for reform”, IBC Merger Control conference (Brussels, April 2016).
  • “Mergers: practical challenges (panel moderator)”, IBC Advanced Competition Law Conference (Brussels, February 2016).
  • “What are the competition risks to your business?”, IBC Legal Compliance & Ethics International (London, November 2015).
  • “Competition challenges from online retailing – new wine in old bottles?”, GCR 7th Annual Brussels: The conference about the bigger picture, Brussels (November 2015).
  • “Due process in competition cases”, IBA Annual Conference, Vienna (October 2015).
  • “Opting to blow the whistle or choosing to walk away?”, The American Lawyer US – EU Legal Summit, Brussels (June 2015).
  • “Cartels – Problems and issues in Japan and Asia”, Kluwer Global Competition Law Forum, Tokyo (May 2015).
  • “Mergers – trends and challenges”, IBC Legal Advanced EU Competition Law, London (April 2015).
  • “Protecting your client in an era of global enforcement,” ABA 2015 Asia Forum, Tokyo (March 2015).
  • “EU Cartel enforcement: Trends and developments,” Korea Competition law forum (September 2014).
  • “Cartels in the EU”, Wolters Kluwer 2nd Annual Competition law forum (September 2014).
  • “Cartels – Problems and Issues China, Europe and US,” Wolters Kluwer 3rd Annual Global Competition law forum, (June 2014).
  • “Most favoured nation clauses” The Law Society webinar (January 2014).
  • “What is the legal basis of the EU cap of bankers’ bonuses,” 2013 City Remuneration Summit (June 2013).
  • “Competition law for in-house legal advisers”, Butterworth’s Conference (September 2013).
  • “How to Prepare in an Era of Aggressive Global Cartel Enforcement,” Japan Institute for Overseas Investment (December 2012).
  • “What’s Wrong with U.S. Class Actions? Rethinking the Class Action Device from a Global Perspective,” ABA Section of International Law (April 2012).
  • “Abuse of dominance: law and economics of pricing.” Competition Law in Transition: Trends and Challenges (June 2011).
  • “The EC Sector Inquiry in the Pharmaceutical Industry.” ABA Section of Antitrust Law: Health Care and Pharmaceuticals Committee (October 2010).
  • “Managing the Worldwide Antitrust Landscape.” Georgetown Global Antitrust Enforcement Symposium (September 2010).
  • “ETHICS: Essentials of Protecting Attorney-Client Communications in the Trenches of Public and Private Antitrust Enforcement: Perspectives from the U.S., Europe and Korea.” Presented by the Compliance & Ethics and International Committees - ABA Spring Meeting (April 2010).
  • “Intellectual property and antitrust in the biotech sector.” Stanford IP Antitrust Symposium Comparing Trends in US and Europe (April 2010).
  • “Article 102 EC and Strategic Patenting - Patent Thickets and Follow-on Patents.” Conference on the Commission’s Pharmaceutical Sector Inquiry, Brussels (January 2009).
  • “Antitrust Developments in Litigation, Mergers and Cartels—A Transatlantic Perspective.” 18th Annual General Council Conference, New York (June 2006).
  • Member, American Bar Association
  • Member. International Bar Association
  • Member, Law Society:
    • Competition Section