Exchange competition, entry, and welfare

Resumen:
We assess the consequences for market quality and welfare of different entry regimes and exchange pricing policies. To do so, we integrate a microstructure model with a free-entry, exchange competition model where exchanges have market power in technological services. Free-entry delivers superior liquidity and welfare outcomes vis-a-vis an unregulated monopoly, but entry can be excessive or insufficient. Depending on the extent of the monopolist's technological services undersupply compared to the first best, a planner can achieve a higher welfare controlling entry or platform fees. Review of Financial Studies, forthcoming