This paper examines the effects of consumer privacy information on firms’ strategies, profits, and competition within an online marketplace, analyzing a setting with an online platform, two retailers, and consumers where information sharing is governed by revenue-sharing contracts. We establish the optimal information-sharing strategy for the online platform and explore the equilibrium outcomes under various consumer privacy choices. Our analysis reveals several key findings. First, sharing all information with retailers is not optimal for the online platform, as sharing only partial information benefits both the platform and retailers. This aligns their profit incentives and allows for greater capture of the consumer surplus. Second, the online platform and retailers prefer a scenario where consumers can protect their privacy, which leads to higher profits. However, consumers are worse off when information is shared with both retailers, as personalized pricing reduces the consumer surplus. Our results suggest that any policy interventions regarding consumer privacy should be carefully considered, accounting for their impact on industry profits and consumer welfare. Overall, this study elucidates the interplay between consumer privacy choices and information-sharing strategies, providing insights for the development of privacy protection regulations.