Maxim SANDIUMENGE I BOY will defend his thesis on Tuesday 30th June, 2026 at 15:00 PM (Auditorium 5, bâtiment TSE and zoom)
Title: Essays in Industrial Organization
Supervisors: Professor Patrick REY
To attend the conference, please contact the secretariat of the TSE Doctoral school.
Memberships are:
- Patrick REY: Professor in Economics, TSE, Université Toulouse Capitole Supervisor
- Pierre DUBOIS: Professor in Economics, Université Toulouse Capitole Examinateur
- Daniel ERSHOV: Assistant Professor in Economics, University College of London Examinateur
- Ali YURUKOGLU: Professor in Economics, Graduate School of Business, Stanford University Rapporteur
- Marc BOURREAU: Professor in Economics, Telecom - Institut Polytechnique de Paris Rapporteur
Abstract :
This dissertation consists of three essays in industrial organization studying vertical relations, foreclosure incentives, and interoperability in digital markets.
The first chapter, Consumer Dynamics and Vertical Relations: Coordination and Foreclosure in a U.S. Consumer Goods Industry, studies how demand dynamics arising from habit formation affect the efficiency of vertical relations, foreclosure incentives, and the overall impact of integration. It develops a dynamic model in which downstream firms have multiple suppliers and face consumers who form habits, and estimates it using scanner data from a U.S. consumer goods industry, where brand loyalty induces strong demand inertia. To solve the high-dimensional dynamic game, the chapter adapts deep reinforcement learning methods to approximate Markov perfect equilibria. The findings reveal that demand dynamics magnify the consequences of any competitive disadvantage, generating two opposing forces. On the one hand, firms moderate upstream margins to preserve the competitiveness of their vertical structure, alleviating coordination problems under separation and reducing the efficiency gains from integration. On the other hand, integrated firms have stronger incentives to disadvantage non-integrated products, since steering consumers today affects future demand through habit formation. Quantitatively, stronger demand dynamics reduce the efficiency gains from integration by up to 35% relative to a static benchmark, while integrated firms reduce prices of integrated products by up to 30% less and foreclose rivals more aggressively. Overall, the chapter shows that intertemporal linkages dampen the pro-competitive effects of vertical mergers and amplify their anti-competitive risks.
The second chapter, Vertical Foreclosure: A Dynamic Perspective, studies how dynamic considerations affect firms’ ability and incentives to foreclose rivals from access to essential inputs. It builds on the canonical successive duopoly framework and introduces intertemporal linkages in the downstream market: the more a firm sells in the first period, the better its ability to compete in the second period. In this environment, intertemporal linkages generate two opposing forces. On the one hand, they amplify the consequences of downstream cost asymmetries, since higher costs today also weaken a firm’s future competitive position, potentially enhancing foreclosure concerns. On the other hand, alternative suppliers may moderate input prices to preserve the future competitiveness of their vertical structure, potentially reducing the scope for foreclosure. The overall effect depends on the feasibility of a counter-merger and the strength of the intertemporal linkages. When counter-mergers are infeasible or dynamics are weak, foreclosure incentives increase; conversely, when counter-mergers are feasible and intertemporal linkages are strong, foreclosure incentives may be substantially mitigated or disappear altogether.
The third chapter, Platform Annexation, is coauthored with Patrick Rey. It studies platform competition and interoperability incentives in the presence of facilitating tools that reduce multi-homing costs. Such tools can intensify competition by limiting platforms’ ability to exploit their network position. At the same time, platforms may have incentives to restrict interoperability or acquire and operate these tools in ways that disadvantage rivals. The chapter analyzes how these incentives depend on the strength of network effects, market asymmetries, and the distribution of multi-homing across platforms. It further studies how asymmetric interoperability choices may allow a platform to attract the rival’s users while limiting reciprocal access, thereby reshaping competitive outcomes.
