This study examines the effects of an information sharing restriction policy that restricts taxi drivers' access to ride requests via ride-hailing apps. We show that the policy significantly decreases the ridership of an affected taxi fleet during times of enforcement but significantly increases the demands at some times of nonenforcement after launch. Furthermore, the traffic on public transportation, including metro, bus, ferry, and park & ride, and the congestion on the surface roads and expressways significantly increase after launching the policy during both enforcement and most nonenforcement times. We also show that the profitability of taxi fleet decreases after the restriction, which supports the notion that information sharing via ride-hailing apps enables them to match not only with more orders but also with those of higher marginal profit. These findings suggest that information sharing via ride-hailing apps can improve the utilization of existing taxi capacity, which further alleviates traffic during alternative times and the burden placed on alternative transportation modes. Policymakers and platform managers should dissect the value of information sharing from that of other aspects (e.g., changes in supply) in on-demand platforms and design policies that more specifically restrict the harmful aspects rather than restricting the use of such apps. A ride-hailing platform is an app-based, two-sided platform that matches riders with vehicles via information technology (IT). In 2015, the Shanghai government introduced a policy to restrict taxi drivers' access to and acceptance of ride requests via ride-hailing apps during certain hours. We conceptualize this policy shock as the restricting of information sharing enabled by IT and collect comprehensive data on various uses of transportation to gauge the economic benefits of this information sharing for existing capacity and its subsequent externalities on other transportation. Through a time series analysis, we identify significant decreases in the ridership of an affected taxi fleet during times of enforcement but significant increases at some times of nonenforcement postlaunch. Furthermore, the traffic on public transportation, via the city's transportation cards, and the congestion on the surface streets and expressways significantly increase after launching the policy during both enforcement and most nonenforcement times. These suggest that information sharing via ride-hailing apps can improve the utilization of existing taxi capacity, which further alleviates traffic during alternative times and the burden placed on alternative transportation modes. Interestingly, our mechanism analysis shows decreased profitability after the restriction, which supports the notion that information sharing via ride-hailing apps reduces drivers' search cost and thus enables them to match not only with more orders but also with those of higher marginal profit. This study contributes to the literature on ride-hailing platforms' impact and the economic value of information sharing and IT by dissecting the compound ride-hailing's impact to extract the value of information sharing enabled by IT and to reveal the underlying mechanism. Practically, we evaluate the policy studied, make postrevision suggestions for general contexts, and provide managerial insights on precise policymaking that best extracts the economic value of information sharing in ride-hailing and general forms of online two-sided platforms. History: D. J. Wu, Senior Editor; Yili (Kevin) Hong, Associate Editor. Funding: This work was supported in part by the National Natural Science Foundation of China [Grants 71729001, 71972047, 71831005, and 91746302]. Supplemental Material: The online appendix is available at https://doi.org/10.1287/isre.2022.1181. [ABSTRACT FROM AUTHOR]