碳交易机制的绿色知识溢出效应OACHSSCD

China's emissions trading scheme(ETS)is a key tool in the green and low-carbon transition.By defining emission rights,capping quotas,and pricing carbon,the ETS turns emissions into a firm cost.Prior work shows effects on emission cuts,energy restructuring,and green innovation.Yet its wider value depends on whether green technology,managerial experience,and low-carbon practices formed by regulated firms can be learned and reused by other firms.Therefore,this paper investigates whether the ETS promotes green knowledge spillovers,the transmission channels involved,and the boundary conditions. Using data from A-share listed firms in China from 2008 to 2024,this paper employs the staggered difference-in-differences(DID)method and finds that carbon emissions trading can promote green knowledge spillovers.Mechanism analysis identifies two channels:the establishment of green responsibility and the transmission of green governance.Heterogeneity tests show that the effect is more pronounced in industries with high market competition,in firms with strong bargaining power,and in firms located outside the Yangtze River Delta. The marginal contributions are threefold.First,this paper constructs a green knowledge spillover indicator based on the stock of green invention authorizations for non-regulated firms connected through board networks to evaluate the construction of a unified carbon market.It captures a direct organizational channel through which green knowledge may be observed and reused.Second,this paper clarifies the transmission from carbon constraints to green knowledge spillovers.As carbon emissions trading increases firms' responses to green issues and integrates low-carbon requirements into routine governance arrangements,the positive effect is achieved not only by increasing managerial responses to green issues and strengthening firms' green responsibility,but also by leading firms to pay more attention to green governance in production and supply chain-related activities.Third,this paper improves the measurement of policy exposure.It manually collects annual lists of regulated firms and uses a staggered DID framework to match policy treatment with the year in which each firm became subject to carbon market regulation. The findings provide several policy implications.First,the carbon market should maintain a stable and credible constraint on covered firms,so that carbon costs can be integrated into firms' long-term investment decisions rather than remain a short-term compliance pressure.Second,policy design should pay attention to whether firms achieve the quota target and whether they generate green technologies and governance experience.Third,regulators should be alert to the possibility that firms with strong market power may respond to carbon costs mainly through price adjustment.If cost pass-through substitutes for technological responses,the positive externalities of the carbon market will also be weakened.