A comprehensive evaluation of the costs and benefits of environmental regulations provides empirical evidence for policymakers to formulate and introduce environmental policies. Firms' profitability and competitiveness manifest their market power and provide the micro foundation for economic development and social stability. Therefore, this paper focus on investigating the impact of air pollution environmental regulation on manufacturing firms' market power, measured by markups, with a difference-in-differences (DID) method. Using air pollution control policy, requiring China's Key Cities for ...
