Platforms have come under criticism from regulatory agencies, policymakers, and media scholars for the unfettered spread of fake news online. A key concern is that, as fake news becomes prevalent, individuals may fall into online "echo chambers" that predominantly expose them only to fake news....

We provide a model of governance in which a board arbitrates between an activist investor and a manager facing reputational concerns. The optimal level of internal board governance depends on both the severity of the agency conflict and the strength of external governance. Internal governance...