Carbon emissions trading policy, social trust and green innovation: A path study based on an informal institution

To clarify the driving effect and pathway of carbon trading policies on green innovation in enterprises, this paper focuses on data from Chinese A-share listed companies from 2007 to 2021, introducing the double-difference model to explore the changes in innovation level under the effect of Carbon Emission Trading Policy on enterprise green transformation. The research findings demonstrate that the adoption of the policy can efficiently encourage green innovation behavior, with green utility model innovation exhibiting a higher incentive effect than green invention innovation. For innovation quantity, the promoting effect is more significant in state-owned enterprises, companies with low technology levels, and enterprises in non-manufacturing industry. Moreover, from both quantitative and qualitative perspectives, the incentive effect of policy is reduced due to funding constraints, whereas government research and development subsidies have strengthened it. Finally, mechanism analysis indicates that the behavior of green innovation in enterprises can be enhanced. The empirical results provide empirical evidence for improving carbon trading policies and formulating differentiated green innovation incentive strategies for enterprises with different characteristics, which has important reference value for promoting sustainable development of enterprises and assisting in the achievement of the "dual carbon" goals.