Regulating FRAND Access to App Stores under the DMA

Speaker: Dr Despoina (Deni) Mantzari, UCL

Chair: Dr Ryan Stones, The City Law School

Discussant: Prof Enrico Bonadio, The City Law School

This seminar is co-organised by the Institute for the Study of European Law (ISEL) and Intellectual Property Engagement Group (IPEG).

Abstract

This talk draws from Despoina Mantzari, ‘Regulating FRAND Access to App Stores under the DMA’ (2026) Journal of Competition Law & Economics, forthcoming.

The article develops a normative framework for interpreting the Fair, Reasonable and Non-Discriminatory (FRAND) platform-access obligation in Article 6(12) of the Digital Markets Act (DMA), with Apple’s iOS App Store as the central case study.

While the DMA couples contestability and fairness, EU enforcement has so far focused almost exclusively on contestability while avoiding the more difficult question of what constitutes a fair access fee. Yet due to network effects and developer lock-in, effective contestability may not materialise, compelling the European Commission to confront the substantive fairness of app-store commissions.

Drawing on FRAND principles in standard essential patents, EU competition law and telecoms regulation, the article shows that none of these frameworks can be transposed directly to digital ecosystems characterised by intangible assets and reciprocal value creation. It argues instead for a principles-based approach built around four propositions: gatekeepers should not be remunerated for network-effect rents; FRAND must reflect the reciprocal value that developers generate for the ecosystem; access pricing should account for the net exchange of value between platform and developer; and fees should, at minimum, reflect Long-Run Average Incremental Costs.

Implemented together, these principles offer a coherent method for operationalising fairness under Article 6(12) and rebalancing value capture in digital markets.

About the speaker

Dr Despoina (Deni) Mantzari is an Associate Professor in Competition Law and Policy, in the Faculty of Laws, UCL where she also serves as co-Director of the Centre for Law, Economics and Society. Her research lies at the intersection of competition law, sector-specific regulation, and public law, and is marked by a distinctive comparative approach spanning the EU, UK, and US, as well as an interdisciplinary methodology drawing on political science and economics. Her scholarship combines doctrinal analysis with qualitative empirical methods and has been supported by the AHRC, ESRC, and the BA/Leverhulme Trust.

She has published widely in leading journals such as the Oxford Journal of Legal Studies, the Modern Law Review, the Journal of Competition Law and Economics, and the Journal of Antitrust Enforcement. Her monograph, Courts, Regulators and the Scrutiny of Economic Evidence – Comparative Perspectives (Oxford University Press, 2022), offers an in-depth examination of how courts and regulators assess complex economic evidence across jurisdictions.

Deni joined UCL in 2019. Previously, she was a Lecturer at the University of Reading School of Law and Programme Director of the LLM in International Commercial Law (2014-2018). Deni holds a PhD from UCL (AHRC doctoral scholarship), an LL.M in European Union Law (distinction) from UCL and a law degree from the National University of Athens, Greece.

In 2013-2014, Deni was a postdoctoral research fellow at the ESRC Centre for Competition Policy at the University of East Anglia, where she undertook research on behavioural economics and comparative (EU, US) antitrust law. In 2010-2011, she was a visiting researcher at the UC Berkeley Boalt Hall School of Law in the USA and in 2016-2017 she was a Fellow at the Institute of Advanced Legal Studies in London where she undertook research on the influence of economic evidence on the discretionary assessments of the UK utility regulators as part of her BA/Leverhulme Small Research Grant.

Deni is co-Director of the Centre for Law, Economics and Society at UCL, an associate fellow of the Centre of Competition Policy at the University of East Anglia and a Fellow of the UK Higher Education Academy. Deni is book review editor for the journal World Competition - Law and Economics Review (Kluwer Law), an associate editor for the Journal of Competition Law and Economics (OUP) and sits on the editorial board of the Journal of Antitrust Enforcement (OUP). She is also joint-Editor of Current Legal Problems. Since 2016, Deni is General Editor for the 'Competition Law of the European Union' treatise published by LexisNexis, succeeding the leading Competition Law Professor, Valentine Korah.

Deni has been invited to the judicial training programme of the European Commission and as a guest lecturer in many institutions. Prior to joining academia, Deni worked as a trainee lawyer and qualified to practice law in Greece (Athens Bar Association).