Ariel Ezrachi is the Slaughter and May Professor of Competition Law and a Fellow of Pembroke College, Oxford. He serves as the Director of the University of Oxford Centre for Competition Law and Policy.

His research interests include European competition law, mergers and acquisitions and cross border transactions. His recently published papers focus on passive investments, excessive pricing, private labels and buyer power.

He is co-editor of the Journal of Antitrust Enforcement (OUP) and the author, editor and co-editor of numerous books, including EU Competition Law, An Analytical Guide to the Leading Cases (4th ed, 2014, Hart), Global Antitrust Compliance Handbook (2014, OUP), Research Handbook on International Competition Law (2012 EE), Intellectual Property and Competition Law: New Frontiers (2011, OUP), Criminalising Cartels: Critical Studies of an International Regulatory Movement (2011, Hart), Article 82 EC - Reflections on its recent evolution (2009, Hart) and Private Labels, Brands and Competition Policy (2009, OUP).

He convenes the Competition Law Group and teaches competition law at graduate and undergraduate levels. He develops training and capacity building programmes in competition law and policy for the private and public sectors, including training programmes for European judges endorsed and subsidised by the European Commission. He is a member of UNCTAD Research Partnership Platform and a former Non-Governmental Advisor to the ICN.


Displaying 1 - 25 of 53. Sorted by year, then title.
Filter by
  • A Ezrachi and Ketan Ahuja, 'Private labels, Brands, and competition enforcement' in D Desai, I Lianos, S Waller (eds), Brands Competition Law and IP ( Cambridge 2015 2015)
  • A Ezrachi, 'Sponge' (2015)
    A look at the international competition law landscape reveals consensus as to the main goals of competition law. Indeed, core economic reasoning and market analysis serve as the backbone to competition analysis and support assimilation of thought and policy worldwide. Orbiting that core, one may identify a wider, heterogeneous, range of policies advanced by competition regimes. These policies are sometimes viewed as external to the pure competition analysis and, as such, may be regarded as illegitimate. Overall, the ‘in’ and ‘out’ methodology presupposes the presence of a legal and analytical structure which defines competition law and to which jurisdictions are expected to align. This paper explores that proposition. It considers the inherent properties of the law and questions the presence of a clear dividing line between competition law and external considerations. It argues that the law, by its nature, provides for an absorbent and flexible platform which soaks up national values and interests. Accordingly, the inherent scope and nature of modern competition laws are not necessarily as consistent and objective as one might like them to be.
  • A Ezrachi and Maurice Stucke, 'The Curious Case of Competition and Quality' (2015) J Antitrust Enforcement
  • Maurice Stucke and A Ezrachi, 'When Competition Fails to Optimise Quality: A Look at Search Engines' (2015) Yale Journal of Law and Technology
  • A Ezrachi and Maria Ioannidou, 'Buyer power in european union merger control ' (2014) European Competition Journal p69
    The examination of buyer power in merger control may relate to one of two forms of power. It may relate to the merging parties’ ability to exercise buyer power to the detriment of consumers. Alternatively, it may relate to the presence of countervailing buyer power that can relax some of the effects generated by an upstream transaction. This paper examines the economic and policy implications of buyer power and reviews the European Commission’s decisions in cases in which buyer power considerations were present. The analysis reviews the weight attributed to buyer power considerations in finding a significant impediment to effective competition or, conversely, the role of countervailing buyer power as a mitigating factor in the analysis of upstream mergers. The discussion highlights a certain gap between the limited emphasis given to buyer power in merger analysis, in contrast to the extensive and heated discussion it triggers outside legal analysis – at policy, social and economic levels.
  • A Ezrachi, EU Competition Law - An Analytical Guide to the Leading Cases ( Hart Publishing 2014)
    This is the fourth edition of the highly practical guide to the leading cases of European Competition Law. It explores the application of Article 101 TFEU, Article 102 TFEU and the European Merger Regulation, as well as the public and private enforcement of Competition Law. In addition, it reviews the intersection between Competition Law and Intellectual Property Rights and the application of Competition Law to State action. Each chapter outlines the relevant laws, regulations and guidelines for each topic. Within this framework, cases are reviewed in summary form, accompanied by analysis and commentary. . . 'This book should be in the library of every competition law practitioner and academic. The summary of cases is first class. But what makes it really stand out is the quality of the commentary and the selection of the material which includes not only the most important European judgements and decisions but also some of the leading cases from the US and European Member States.' Ali Nikpay, Gibson, Dunn & Crutcher LLP, Former Senior Director, Office of Fair Trading . . 'The study of EU Competition law requires the analysis and understanding of a number of increasingly complex European Commission and European Court decisions. Through the provision of case summaries, excerpts from the important passages and concise commentary linking these decisions to other key case law and Commission documents, this unique and impressive book, now in its fourth edition, provides the student and practitioner of EU competition law with an extremely clear and useful introduction to these leading decisions.' Dr Kathryn McMahon, Associate Professor, School of Law, University of Warwick . . 'This book is especially valuable for competition law specialists in Europe and abroad who are interested in the jurisprudence and policy of the European Union and its member states. Familiarity with the European regime is essential for proficiency in competition law today, and this volume provides an excellent foundation.' William E Kovacic, Global Competition Professor of Law and Policy, George Washington University Law School, Former Chairman, US Federal Trade Commission . . 'The Guide is an invaluable tool for both students and practitioners. It provides a compact overview on the fundamental cases and highlights the essential problems in a clear and sharp analysis.' Dr Christoph Voelk, Antitrust Practice Group, McDermott, Will & Emery LLP
  • DD Sokol , A Ezrachi and D Crane (Editors), Global Antitrust and Compliance Handbook ( OUP 2014)
    The proliferation of antitrust enforcement regimes around the world has transformed the enforcement landscape in recent decades. This trend has led to increased focus on the competitiveness of markets and the curtailment of anticompetitive activities, to the benefit of consumers. It has also led to increased bilateral, regional and multinational cooperation resulting in a gradual process of assimilation of thought and law. However, while record numbers of competition agencies progressively apply similar principles and law, competition law enforcement remains domestic in nature. Indeed, a look at the active jurisdictions reveals a range of substantive and procedural approaches. Differences in the competition agencies mandate, priorities and enforcement powers, as well as different political, social and legal environments are only several of the variants which underscore the heterogeneous enforcement landscape. This reality presents challenges for companies and undertakings operating across borders. With increased globalization of business and increased extraterritorial application of competition laws, it is often the case that an activity, agreement or transaction will be subjected to a range of overlapping competition regimes. Subsequently, the task of managing the legal and financial risks associated with competition law infringements requires a careful exploration of the law and practices around the world. This multi-jurisdictional compliance guide addresses this complexity and offers a comprehensive and detailed multi-country review of critical antitrust compliance issues. The book outlines the laws and practice in forty three of the leading antitrust jurisdictions around the world. With compliance requirements in mind, this book provides businessmen, law firms and in-house lawyers with the necessary information to explore the changing global antitrust landscape. This book is a resource for those responsible for competition and corporate compliance programs and for those interested in the international enforcement landscape of competition law. It assists in tailoring global compliance programs while considering multijurisdictional effects and policies. In addition, it provides a clear and accessible benchmark for the consideration of agreements, activities and transactions on a case by case basis. Contributions to this book have been authored by leading competition law practitioners from their respective jurisdictions. Chapters in this guide enable assessment of personal and corporate risk exposure. The reader will find information on each regime’s laws and practice. Areas covered include enforcement procedure and substance. These include, among others, the enforcement environment and enforcement priorities, leniency programs, penalties, fines and individual sanctions. In addition chapters outline the laws applicable to horizontal and vertical agreements, market power and the abuse of a dominant position and merger control.
  • A Ezrachi and Maria Ioannidou, 'Internationalization of competition law and policy: domestic perspective ' (2014) Journal of International and Comparative Law
    Recent decades have witnessed a marked internationalization of competition law enforcement and dialogue. Multinational, regional and bilateral efforts, have contributed to the approximation of competition law regimes worldwide and to collaborative enforcement. However, notwithstanding these valuable developments, domestic social, political, industrial and market considerations still affect the scope and application of national competition laws. This paper explores the meeting points between the domestic perspective of competition law enforcement and growing international collaboration and enforcement efforts. In doing so, it highlights the intrinsic national nature which is embedded in the DNA of competition law and the natural limits of international convergence and collaboration in this area.
  • A Ezrachi and Maurice E. Stucke, 'The curious case of competition and quality ' (2014)
    A central mantra of competition policy is that competitive market forces, besides lowering prices, can increase efficiency, product quality, the level of services, the number of choices, and ultimately consumers’ welfare. Indeed, the antitrust community generally accepts a relationship between greater competition and lower prices and uses the latter as the prime metric in assessing competitive behavior and the effects on consumer welfare. Alongside the consideration of price, competition authorities recognize that quality can be as, if not more, important in some markets. But as competition authorities also recognize, identifying the dimensions of competition important to many consumers is difficult. Even when these dimensions of quality are identified, measuring them represents additional challenges. To circumvent these challenges, competition authorities rely on several heuristics when assessing a merger’s, cartel’s or monopolistic restraint’s impact on quality. One heuristic is that more competition will generally increase quality for a given price or reduce price for a given level of quality. A second heuristic is that when prices and quality vary, consumers will weigh the offerings using an internal price-quality metric. Price adjusts for quality, and consumers rely on the heuristic “you get what you pay for.” Often the heuristics work well for the competition authorities. However, at times, market realities are more complex and these heuristics fail to reflect the relationship between competition and quality. In this paper we focus on these instances in which the positive correlation between competition and quality breaks down. We explore two necessary, but not sufficient, variables, which affect that correlation. The first relates to the consumers’ limited ability to accurately assess quality differences. The second concerns imperfect information flows that make it difficult or costly to convey to consumers the products’ or services’ inherent quality differences. Companies recognize that neither they nor their competitors can easily or inexpensively convey to consumers the inherent quality differences in their and their competitors’ product offerings. With these variables in mind, we consider instances when an increase in competition will not increase quality (when one would expect it should) and when competition is inversely correlated with quality, and its increase would lead to quality degradation. Importantly, we do not posit a normative argument: namely that consumers are choosing poor quality goods and services (e.g., reality television shows) when they should be demanding higher quality fare (e.g., investigative news programs). Nor do we posit a social welfare argument, namely competition involving status goods (where price may correlate more with conspicuous consumption than quality), which increases envy to the detriment of overall well-being. Our assumption is that while different customers have different desires and seek a range of quality, many customers for certain goods and services desire a similar specific dimension of quality. Our focus is on the ability of the competitive process to deliver that desired quality attribute.
  • A Ezrachi and Mark Williams , 'Competition Law and the Regulation of Buyer Power and Buyer Cartels in China and Hong Kong' (2013) Asian Journal of Comparative Law
  • A Ezrachi, 'Cross Border Transfer of Wealth – Reflections on Competition Law and Developing Economies ' in Sokol and Lianos (ed), The Global Limits of Competition Law (Stanford University Press 2013)
  • A Ezrachi and J Thanassoulis, 'Upstream Horizontal Mergers and (the Absence of) Retail Price Effects' (2013) Journal of Competition Law and Economics
    The paper explores the retail price effects of upstream and mid stream horizontal mergers. It questions the prevailing assumption in merger review according to which such transactions will have similar effects on retail price as that of downstream horizontal mergers. The analysis illustrates how a sophisticated profit-maximizing merged entity may find it more profitable to enter into efficient contracts which seek to maximise the profit of the distribution channel, and so ensure that retail prices are not raised. The merged entity uses its market power and improved bargaining position to extract as much of that profit as possible from the retailer. We therefore argue that one cannot simply assume a direct link between the creation of market power upstream following a merger transaction, and the subsequent increase in retail prices. An analysis of the effects of upstream mergers on retail prices should call for a more nuanced appraisal which distinguishes the transfer of wealth within the operators in the distribution chain from the possible price impacts on final consumers.
    ISBN: 1744-6414
  • A Ezrachi, 'Buying Alliances and Input Price Fixing – In Search of a European Enforcement Standard ' (2012) Journal of Competition Law & Economics
    This paper considers the welfare implications of input price fixing and the enforcement standard to be applied to these arrangements. It explores the way in which European competition law approaches input price fixing, the scope of the object-based approach and the instances in which effects-based analysis may be used in the appraisal. In doing so, the paper sets to clarify the legal approach to price fixing of procured input. It outlines a possible benchmark for the assessment of input price fixing, with the aim of sharpening the dividing line between instances which restrict competition by object, and those which necessitate consideration of effects.
    ISBN: 1744-6414
  • A Ezrachi and Koen de Jong, 'Buyer Power, Private Labels and the Welfare Consequences of Quality Erosion' (2012) European Competition Law Review
    The paper explores the effects buyer power may have on product quality. It argues that, at times, excessive pressure on input price will trigger direct welfare costs to consumers in the form of disguised inferior products. To illustrate quality erosion, the discussion focuses on the unique area of private labels and the relationship between the powerful buyer and its private-label supplier.
  • A Ezrachi, EU Competition Law, An Analytical Guide to the Leading Cases ( 3rd ed, Hart 2012)
  • A Ezrachi and M Maggiolino, 'European Competition Law, Compulsory Licensing and Innovation' (2012) Journal of Competition Law and Economics
    This article explores the interface between competition law and intellectual property rights (IPRs) in the context of compulsory licensing. It considers how European competition law has been applied to limit the protection awarded to IPR holders and reflects on the remedy of compulsory licensing. In doing so, the article considers how current policies may affect innovation and welfare. In our analysis, we consider two questions that are inter-linked. The first relates to the threshold for finding that a refusal to license IPRs amounts to an abuse of a dominant position. We consider whether the current European threshold for intervention is adequate and clear. Our analysis illustrates that the use of competition law as an external balancing tool has gradually eroded the protection conferred by IPR. Furthermore we show that the European Commission’s Guidance Paper on Article 102 of the Treaty on the Functioning of the European Union (TFEU)1 has contributed to this trend. We argue that these processes have blurred the principles which limit the application of competition law to IPR, creating a potentially detrimental effect on competition and innovation. We consider the characteristics of the compulsory license remedy and reflect on its adequacy in resolving competitive and innovative injuries caused by the refusal to license. In doing so, we review the aims of compulsory licensing, as well as its advantages and disadvantages. We then propose an offense-remedy distinction, which allows substantive analysis of abuse, independent of the remedy. This method enables antitrust authorities to evaluate the offense with less risk of reaching a conclusion that is based on a false positive.
    ISBN: 1744-6414
  • A Ezrachi, International Research Handbook on Competition Law (Ed, EE, forthcoming 2012)
  • A Ezrachi, 'The Scope and Limits of 'International Competition Law'' in Ariel Ezrachi (ed), International Research Handbook on Competition Law (Edward Elgar 2012)
  • A Ezrachi and H Qaqaya, 'UNCTAD’s Collaborative Information Platform' (2012) 4-2012 Concurrences Journal
    The application of competition law in an international setting has long been a challenging area for competition agencies. Legal and practical obstacles often limit an agency’s ability to obtain information on multinational violations and engage in effective enforcement and prosecution. These limitations have been particularly noticeable in the case of developing countries and economies in transition. These regimes are characterised by limited enforcement capacity and tend to focus their attention on domestic violators and on efforts to foster a ‘competition culture’. The challenge of tackling sophisticated cross-border anticompetitive activity and the imposition of effective sanctions on international violators may be beyond their reach. Unfortunately, the limited enforcement capacity of these regimes often results in an increased and disproportionate exposure to multinational anticompetitive activity. This exposure is particularly harmful given the ever growing level of cross-border trade. Indeed, in many instances, unless the cross-border activity is challenged by other, more powerful jurisdictions, developing economies and economies in transition remain exposed to negative transfer of wealth. This reality serves as a powerful incentive for these regimes to enhance their enforcement capacity in order to effectively tackle cross-border infringements. To facilitate these efforts, UNCTAD has recently launched a new initiative that will foster transparent information flow and collaboration between competition agencies. This initiative – known as the Collaborative Information Platform - forms part of UNCTAD’s on-going work on international cooperation and enforcement.
  • A Ezrachi and Maria Ioannidou, '‘Public Compensation’ in Competition Cases – A Complementary Mechanism to Damages Actions ' (2012) Jnl of Euro Competition Law & Practice
    EU competition law enforcement has undergone significant changes in the past decade, aimed at improving its effectiveness by employing more actors (national competition authorities and courts) and more ‘flexible’ procedures (commitments decisions and settlements). Occupying centre stage alongside these developments were efforts to advance private EU competition law enforcement and consumer involvement therein. Yet, while the number of damages actions in competition cases has steadily increased in some Member States, this increase has been modest and uneven across Europe. Procedural difficulties, excessive costs, risks and the multitude of legal systems involved, are only some of the obstacles still curtailing the availability of effective judicial redress in competition law cases. In addition, difficulties in launching group actions and adopting a harmonised Euro-wide collective redress mechanism, further limit access to corrective justice. This paper addresses shortcomings in the private enforcement of competition laws across Europe. It explores the possibility and desirability of deploying public enforcement to promote some of the objectives traditionally linked to damages actions in national courts. More specifically, it advocates in favour of including elements of compensation for injured parties, as part of the public enforcement of competition law (hereafter ‘Public Compensation’). Under the proposed mechanism, at the end of a public investigation, the competition authority would be able to impose not only a fine but also award a certain form of compensation to the injured parties, either individually identified or defined more broadly as the injured class. This mechanism provides an attractive vehicle for supplementing damage claims; narrowing the gaps in corrective justice, while fulfilling the traditional deterrent function of public enforcement. These benefits, we argue, justify consideration of a formal approach toward Public Compensation, which would facilitate its implementation across the European Union. Such mechanism could be implemented alongside possible future changes to the private enforcement landscape. This paper advances a two-fold argument addressing the questions of ‘why’ and ‘how’ Public Compensation is desirable. We begin by identifying the gap in the enforcement system that Public Compensation could fill, and offer further normative justifications for Public Compensation. We then consider the merit in advancing a more formal, fused approach toward competition law enforcement. Subsequently we move on to review cases in which the competition authority imposed or accepted compensation as part of the public inquiry. These cases provide inspiration for the ensuing proposal of a formal, institutional approach.
    ISBN: 2041-7764
  • A Ezrachi and Maria Ioannidou, 'Access to Justice in European Competition Law –Public Enforcement as a Supplementary Channel for ‘Corrective Compensation'' (2011) APLR 195
  • A Ezrachi, 'Competition Law Enforcement and Refusal to Licence - The Changing Boundaries of Article 102 TFEU' in S Anderman, A Ezrachi (ed), Intellectual Property and Competition Law: New Frontiers ( 2011)
  • A Ezrachi and J Kindl, 'Criminalisation of Cartel Activity – A Desirable Goal for India’s Competition Regime? ' (2011) 2011- 23(1) NLSIR
  • A Ezrachi and C Beaton-Wells (Editors), Criminalising Cartels: A critical interdisciplinary study of an international regulatory movement ( Hart 2011)
    This book is inspired by the international movement towards the criminalisation of cartel conduct over the last decade. Led by US enforcers, criminalisation has been supported by a growing number of regulators and governments. It derives its support from the simple yet forceful proposition that criminal sanctions, particularly jail time, are the most effective deterrent to such activity. However, criminalisation is much more complex than that basic proposition suggests. There is complexity both in terms of the various forces that are driving and shaping the movement (economic, political and social) and in the effects on the various actors involved in it (government, enforcement agencies, the business community, judiciary, legal profession and general public). Featuring contributions from authors who have been at the forefront of the debate around the world, this substantial 19-chapter volume captures the richness of the criminalisation phenomenon and considers its implications for building an effective criminal cartel regime, particularly outside of the US. It adopts a range of approaches, including general theoretical perspectives (from criminal theory, economics, political science, regulation and criminology) and case-studies of the experience with the design and enforcement of existing or contemplated criminal cartel regimes in various jurisdictions (including in Australia, Canada, EU, Germany, Ireland and the UK). The book also explores the international dimensions of criminalisation - its specific practical consequences (such as increased potential for extradition) as well as its more general implications for trends of harmonisation or convergence in competition law and enforcement.
  • A Ezrachi and S Anderman (Editors), Intellectual Property and Competition Law: New Frontiers ( OUP 2011)




Research programmes

Research Interests

Competition Law

Options taught

Competition Law

Research projects