Fintech et blockchain : Enjeux en organisation industrielle et de gestion des réseaux financiers

Abstract

Innovation has long shaped economic growth and welfare, but in banking and finance it generates a paradox: while hailed as revolutionary, it often proves fragile and rarely displaces incumbents. This dissertation investigates how FinTech and blockchain innovations could disrupt the organizational structures and dynamics of financial networks, focusing on competition, governance, and trust.The second chapter (as the first is the introduction) examines FinTech through the lens of industrial economics. Using an extended Hotelling model and original data from CIFRE company Shine, it shows that although FinTech entrants offer low-cost, mobile-native services, they struggle to achieve profitability and rarely threaten banks' market share. Traditional institutions adapt their strategies and preserve positive market share and profits, highlighting the structural resilience of incumbents and the persistent challenges faced by newcomers. This study achieves the notable contribution of offering a quantitative measure of the gap that prevents FinTechs from reaching profitability. This chapter thus provides new theoretical and empirical evidence on how geography and network structures shape competitive dynamics in modern banking, while also highlighting the persistent challenges FinTechs face in achieving profitability.The third chapter addresses blockchain as a more radical institutional innovation. Unlike FinTech firms, blockchain is not a new competitor but an alternative governance mechanism that challenges the central role of banks. Drawing on transaction cost economics (TCE theory), the analysis conceptualizes blockchain, smart contracts, and decentralized autonomous organizations (DAOs) as hybrid governance forms positioned between markets and firms. These structures reduce some transaction costs but face inherent limitations in price discovery, adaptability, and enforcement, thereby reshaping rather than replacing financial institutions. This chapter contributes both to a better understanding of blockchain networks through the lens of transaction cost economics (TCE) and to the development of TCE theory itself by introducing a new hybrid form of governance.The fourth chapter study to the question of trust. While blockchain is built on “trustless” cryptographic systems, empirical analysis of major Decentralized Finance (DeFi) protocols shows that social and reputational dynamics remain indispensable. A Social Network Analysis (SNA) of DAO governance forums reveals hierarchical patterns, reputation effects, and off-chain trust systems that supplement algorithmic trust. This chapter therefore provides evidence into multi-level trust formation in blockchain networks and DAOs, showing that while blockchain replaces some institutional functions with cryptographic mechanisms, social and reputational dimensions remain essential to sustaining decentralized governance.Together, these findings challenge the narrative of imminent creative destruction in financial services. FinTech and blockchain foster important transformations, yet their disruptive impact is constrained by market structures, institutional dynamics, and the persistent need for social trust. By combining theoretical modelling, empirical evidence, and network analysis, this dissertation contributes to a nuanced understanding of how financial innovations evolve, not as outright replacements of traditional institutions, but as complex reconfigurations within existing networks.