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By Giulia Galletti and Evangelia Kostopoulou
In this interview, Assimakis Komninos, Partner at White & Case in Brussels, discusses key developments in competition litigation and procedure, and explores the intersection of antitrust enforcement, digital markets, and innovation.
Question One: In practice, which procedural levers are most outcome-determinative in EU litigation: the framing of pleas in law, the discipline of evidentiary annexes, access-to-file disputes, timing and scope of RFIs, interim measures, or the way parties build the record during the administrative phase?
If you had to pick one procedural mistake that repeatedly undermines otherwise strong substantive arguments, what is it?
Answer: A clear distinction must be drawn between administrative proceedings before the European Commission and judicial review before the EU Courts. This distinction is not merely procedural; it reflects two different institutional logics, two different objectives, and two different strategic environments. Although consistency of narrative across stages remains essential, the way in which a case is managed, argued, and prioritised changes fundamentally once it moves from Brussels to Luxembourg.
At the administrative stage, the dominant objective is to prevent the adoption of an infringement decision or, at minimum, to reduce its scope and impact. Proceedings before the Commission unfold within an investigative framework in which the authority combines fact-finding, prosecutorial initiative, and decision-making power. In that context, cooperation is often strategically rational. Constructive engagement with case handlers, responsiveness to requests for information, and a willingness to address specific concerns may narrow the theory of harm, remove peripheral allegations, or lead to commitments that avoid or mitigate sanctions. The central logic is one of strategic containment; shaping the contours of the case before they solidify into a formal decision.
Yet cooperation is not an absolute imperative. Where it becomes clear that the Commission is likely to adopt an infringement decision, undertakings face a more complex calculus. Engaging extensively with weak points in the Commission’s reasoning may result in strengthening the eventual decision, which would reduce the prospects of successful annulment. Administrative advocacy and judicial advocacy are not perfectly aligned. The question is therefore not whether to cooperate, but how far, on which points, and with what anticipation of subsequent litigation. This requires an assessment not only of legal merits but also of institutional dynamics and enforcement priorities. Discretion operates within a broader policy environment, and strategic positioning must take that context into account.
Once the case reaches the General Court, the framework shifts from administrative persuasion to structured contestation. The application for annulment becomes the foundational document. It does not merely introduce arguments; it defines the scope of review and structures the dispute. The pleas in law determine how the Commission’s defence will be organised and, in practice, how the Court will approach its assessment. A poorly structured or unfocused application may irreversibly weaken the case, regardless of the underlying substantive strength.
A recurring weakness in complex competition litigation is excessive breadth. Decisions may run to hundreds of pages, and the temptation to challenge every aspect is considerable. However, attempting to contest everything risks diluting the most persuasive arguments. Judicial review before the EU Courts is intensive but disciplined. The Court expects precise engagement with factual findings, economic assessment, and legal reasoning. Abstract invocations of burden of proof or standard of proof, unconnected to concrete evidentiary shortcomings, rarely carry weight. What matters is demonstrating, with clarity and selectivity, where the Commission’s analysis is materially flawed and why those flaws are outcome-determinative.
The oral hearing performs a complementary but distinct function. By the time of the hearing, the case had already been shaped by written pleadings and internal judicial preparation. The purpose of oral argument is not to reproduce technical submissions, but to provide coherence, context, and persuasive synthesis. It is an opportunity to step back from detail and articulate the broader logic of the case. Credibility, clarity, and narrative structure are decisive at this stage.
The overarching lesson is one of procedural discipline and strategic coherence. Effective defence in EU competition law requires anticipating judicial scrutiny already at the administrative phase, while avoiding premature litigation tactics that undermine opportunities for resolution. It requires prioritising decisive pleas over secondary points and aligning factual contestation with doctrinal argument. Above all, it demands recognition that EU competition proceedings form a continuum: the administrative and judicial phases are distinct in form, but interconnected in consequence. Success depends on managing that transition with foresight, focus, and analytical restraint.
Question two: In digital markets, how should one distinguish between legitimate innovation and unlawful foreclosure when the contested conduct is embedded in product design or business architecture?
Answer: The increasing centrality of digital platforms has shifted the focus of competition enforcement from isolated contractual practices to the architecture of products and ecosystems themselves. Whereas traditional EU competition law concentrated on discrete forms of conduct, such as exclusivity clauses, tying, or rebate schemes, digital cases frequently involve design choices: default settings, interoperability restrictions, data integration, self-preferencing mechanisms, and technical integration within multi-sided platforms. The legal difficulty lies in the fact that such features are often integral to the functioning of the product and may simultaneously generate efficiencies and exclusionary effects.
At the outset, it is essential to reaffirm that EU competition law does not prohibit dominance as such, nor does it prohibit successful innovation. The benchmark remains whether the conduct departs from competition on the merits. In digital markets, however, this assessment becomes structurally more complex because design choices are rarely neutral. They can embed strategic advantages directly into the product’s architecture, making exclusion less visible and more difficult to disentangle from legitimate technical optimisation.
The distinction between legitimate innovation and unlawful foreclosure must therefore rest on effects rather than form. The analysis should examine whether the design choice produces actual or likely exclusionary effects that are not justified by objective efficiencies. This requires a structured inquiry. First, the authority must identify the competitive parameter allegedly distorted, whether access, visibility, interoperability, or switching possibilities. Second, it must assess whether the conduct materially restricts competitors’ ability to compete on the merits in a manner that produces consumer harm. Third, it must evaluate whether the design choice is objectively necessary or efficiency-enhancing, and whether less restrictive alternatives would achieve comparable benefits.
Particular caution is required where intervention risks sliding from conduct control into de facto regulation of business models. Competition authorities are mandated to assess legality, not to determine optimal product design. When enforcement begins to prescribe how ecosystems should be structured, the line between ex post competition law and ex ante regulatory governance becomes blurred. This is especially sensitive in fast-moving technological environments, where product integration and ecosystem coherence may themselves be sources of consumer value.
Recent judicial reasoning suggests an increased sensitivity toward access, fairness, and the protection of competitive opportunities within digital ecosystems. While this may reflect broader concerns about entrenched market power and tipping dynamics, it must remain anchored in a coherent legal standard. Overemphasis on competitor protection risks transforming competition law into a tool for equalising outcomes rather than safeguarding the competitive process.
Ultimately, the doctrinal anchor remains consumer welfare understood dynamically. The question is not whether a dominant firm’s design choice disadvantages rivals, but whether it undermines the competitive process in a way that harms users through reduced choice, innovation, or quality over time. Preserving this analytical discipline is essential. Digital complexity does not justify abandoning established principles; rather, it requires their careful and technologically informed application.
Question three: When harm is dynamic or innovation-based, and the counterfactual is probabilistic, what types of evidence carry persuasive weight before the EU Courts?
Answer: Cases involving dynamic or innovation-based harm raise acute evidentiary challenges because they require courts to assess not only present market conditions but also plausible future developments. The counterfactual, the market situation absent the contested conduct, is inherently uncertain. In such contexts, the central issue is not whether the future can be predicted with certainty, but whether the authority has demonstrated, to the requisite legal standard, that anticompetitive effects are sufficiently likely and substantiated.
In the framework of Articles 101 and 102 TFEU, enforcement practice traditionally relies on established exclusionary theories grounded in observable market effects. Dynamic harm, such as innovation suppression or ecosystem entrenchment, typically reinforces rather than replaces conventional theories of foreclosure. Courts expect the Commission to anchor its reasoning in concrete market realities: current competitive constraints, barriers to entry, and measurable effects on rivals. Purely forward-looking narratives rarely suffice on their own. Where innovation arguments are advanced, they must be closely linked to demonstrable structural conditions and credible mechanisms of harm.
By contrast, in merger control, dynamic and innovation-based theories may occupy a central place in the analysis. Because merger assessment is inherently prospective, the counterfactual inquiry is unavoidable. In that context, certain categories of evidence tend to carry particularly persuasive weight. Internal documents revealing strategic intent, such as plans to eliminate nascent competitors or internal assessments of innovation rivalry, are often highly influential, as they provide contemporaneous insight into the parties’ expectations. Market structure analysis, including evidence of entry barriers and concentration in innovation spaces, also plays a decisive role. Examination of R&D pipelines, overlap in technological capabilities, and the existence of potential or emerging competition can substantiate claims of future harm. Economic modelling of counterfactual scenarios may contribute, but its probative value depends on methodological robustness and empirical grounding.
Despite the forward-looking nature of such assessments, the EU Courts remain cautious toward speculative reasoning. Assertions of long-term innovation harm must be supported by evidence demonstrating plausibility and likelihood, not mere theoretical possibility. Quantitative indicators, documentary evidence, and consistent economic reasoning are generally more persuasive than abstract probabilistic claims. Courts are particularly attentive to whether the authority has clearly articulated the causal mechanism linking the conduct or concentration to the predicted reduction in innovation or competition.
In antitrust enforcement, therefore, dynamic harm arguments tend to function as complementary considerations, reinforcing findings grounded in present exclusionary effects. In merger control, they may be central but must still meet the standard of proof applicable to prospective assessments. Across both domains, the decisive factor is evidentiary coherence: the ability to translate uncertainty into a structured, evidence-based demonstration of likely anticompetitive outcomes, while avoiding conjecture.
Question four: How should EU enforcement balance effective oversight with legal certainty where digital platforms face parallel proceedings under EU, national, and third-country regimes?
Answer: The proliferation of parallel proceedings has become a structural feature of digital enforcement. Large platforms frequently operate across jurisdictions and across regulatory frameworks, which exposes them to simultaneous scrutiny by the European Commission, national competition authorities, and third-country regulators. The challenge lies in reconciling robust enforcement with the need for coherence, predictability, and legal certainty.
A first distinction must be drawn between extra-EU and intra-EU parallelism. Outside the European Union, multiple jurisdictions may pursue similar or related investigations concerning the same business practices. While international convergence is encouraged through networks such as the International Competition Network and the OECD, enforcement philosophies, procedural safeguards, and remedial approaches remain heterogeneous. Global firms may therefore face cumulative obligations or inconsistent outcomes. From a systemic perspective, this fragmentation is difficult to eliminate entirely, as each jurisdiction retains sovereignty over competition policy. The objective in this sphere is not uniformity, but coordination and mutual awareness to reduce duplicative burdens and conflicting remedies.
Within the European Union, however, the issue is more institutionally sensitive. Regulation 1/2003 establishes a framework for cooperation and allocation of competence between the Commission and national competition authorities. Its purpose is to ensure consistent application of Articles 101 and 102 TFEU and to prevent fragmentation of the internal market. Parallel investigations or carve-outs, where both the Commission and national authorities examine closely related conduct, risk undermining that objective. Divergent assessments, overlapping remedies, or inconsistent timing may weaken legal certainty and increase compliance complexity.
The introduction of the Digital Markets Act adds a further layer. As a harmonisation instrument, the DMA aims to create uniform obligations for designated gatekeepers across the Union. Its effectiveness depends on centralized and coherent enforcement. If national authorities were to pursue overlapping or inconsistent interventions in areas comprehensively regulated by the DMA, the resulting patchwork could dilute its harmonising function. Legal certainty for undertakings would be compromised, and the internal market logic underpinning the instrument would be weakened.
At the same time, effective oversight requires that enforcement gaps do not emerge. National authorities retain competence in areas not fully harmonised, and coordination mechanisms must allow flexibility without sacrificing coherence. The institutional challenge is therefore one of balance: preserving decentralised vigilance while avoiding regulatory fragmentation.
Ultimately, the credibility of EU enforcement depends not only on its substantive robustness but also on its procedural consistency. For global digital undertakings, predictability of legal obligations is an essential component of the rule of law. Ensuring that parallel proceedings do not produce contradictory or cumulative distortions remains one of the central governance questions in contemporary competition enforcement.
Assimakis KOMNINOS
Assimakis Komninos is a Partner at White & Case in Brussels, specialising in EU competition law and complex antitrust litigation. His practice focuses on abuse of dominance, restrictive agreements, merger control reviews, and regulatory matters under the Digital Markets Act (DMA) and Digital Services Act (DSA).
He represents clients before the European Commission, the Court of Justice of the European Union, national competition authorities, and courts across Europe, as well as in international arbitration proceedings. Over the course of his career, he has acted in a number of high-profile competition cases, including representing Google in the Android and Heureka cases and Amazon in the Italian BuyBox investigation.
Assimakis Komninos previously served as Commissioner and Member of the Board of the Hellenic Competition Commission. He is also a Visiting Professor at Université Panthéon-Assas (Paris II) and a member of the Executive Committee of the Global Competition Law Centre at the College of Europe.
He holds a PhD from the European University Institute, an LL.M. from the New York University School of Law, an LL.M. from the University of Cambridge, and an LL.B. from the National and Kapodistrian University of Athens.
Giulia GALLETTI
Giulia Galletti is an LL.M. candidate in European Legal Studies at the College of Europe. She holds a Master's degree in Law from the University of Bologna and an LL.M. from King’s College London, and has been admitted to the Italian Bar.
She previously trained at an international law firm and completed a Blue Book traineeship at the European Commission (DG COMP). Her research interests include Competition Law and Economics, Financial Services, and International Trade.
She currently serves as President of the Competition Society at the College of Europe.
Evangelia KOSTOPOULOU
Evangelia Kostopoulou is an LL.M. candidate in European Legal Studies at the College of Europe. She holds a master's degree in law and technology from Tilburg University and is admitted to the Greek Bar. She previously trained at EY Law, one of the largest national law firms in Greece.
Her academic interests lie in EU Competition Law, and she is particularly interested in questions of consumer protection, sustainability transitions, and digital platform governance. Alongside these substantive concerns, she has a strong interest in competition procedure and the procedural safeguards that structure EU antitrust enforcement.
She currently serves as a Board Member of the Competition Society at the College of Europe.
