with Fabio Manenti (UNIPD) and Massimo Motta (BSE & UPF)
We study a dominant digital platform that ties an auxiliary platform service into its core product, competing with a rival that users can reach either through the dominant platform or via a direct channel. Tying can be directly pro-competitive (by improving convenience and reducing search or switching costs) but it can also have indirect effects, for example by shifting network size or altering rivals’ investment incentives, which may change competition and consumer surplus. Examples include Google integrating vertical services into search results, Microsoft bundling Teams with Office 365, and Meta integrating Marketplace into Facebook and an AI assistant into WhatsApp.
Status: Preliminary Draft
with Gaston Llanes (PUC Chile)
We study within-device competition between integrated (e.g., Google Play or Apple's App Store) and third-party app stores. We find that competition does not lead to lower commission fees. The reason is that ad valorem fee setting implies a negative pass through of fees to app prices (Edgeworth paradox), which induces developers to adopt price parity across stores (without being required to do so by the integrated platform). As a result, consumers have no incentives to install third-party stores, and the integrated store becomes a natural monopoly. Eliminating default advantages through choice screens is unlikely to be effective. Allowing developers to steer consumers towards alternative subscription methods lowers commission fees and increases the number of apps, but also increases app prices, which may decrease consumer surplus.
Status: SSRN Working Paper, 2025. New version soon.
with Anna D'Annunzio (Tor Vergata, Rome), Bruno Jullien (TSE), and Yassine Lefouili (TSE)
This paper examines how horizontal mergers affect firms’ incentives to invest in R&D leading to the development of new products. We characterize the impact of a merger to monopoly and a 3-to-2 merger on equilibrium innovation efforts and consumer surplus, absent efficiency gains and spillovers. We show that a 3-to-2 merger directly alters the outsider’s innovation incentives by shifting its best-response function upward, and we analyze how this mechanism affects merger outcomes for innovation and consumer surplus. Finally, we examine how efficiency gains and remedies modify post-merger innovation efforts.
Status: TSE Working Paper, 2025. Submitted.
more to come
Credits for image-generation to ChatGPT 5.2
