Transportation network companies (TNCs) such as Uber and Lyft have drawn scrutiny for the way they have upended urban transportation systems and heightened the precarity of taxi drivers. Less attention has been paid to their implications for democratic workplaces. This article provides a comparative study of Uber and Lyft's impacts on taxi worker cooperatives in three cities: Philadelphia, Denver, and Austin. Drawing on interviews with drivers, regulators, and other transportation stakeholders, we observe three major effects. First, TNCs have opened doors for cooperatives by undercutting taxi oligopolies and lowering regulatory barriers to entry. Second, they have intensified market pressures that make it difficult for start‐up co‐ops to survive. Finally, competition from TNCs has led co‐ops to shift resources away from democratic decision making and toward financial bottom lines. These findings paint a complex picture of workplace democracy's potential and limits as a response to the sharing economy's competitive and neoliberal underbelly.