Impact of Carbon Emission Trading Policy on Green Technological Innovation Spillovers: From the Perspective of Industry Low-Carbon Transformation

The transition of corporate green technological innovation from individual breakthroughs to industry-wide spillovers is a central objective of the carbon emission trading policy in facilitating comprehensive industrial green upgrading and serves as a critical metric for evaluating its systemic effectiveness. Treating the carbon emission trading policy as a quasi-natural experiment, this paper utilizes panel data of Chinese A-share listed companies on the Shanghai and Shenzhen stock exchanges from 2010 to 2024. Employing a multi-period difference-in-differences (DID) approach, the study investigates the impact and underlying mechanisms of the policy on green technological innovation spillovers from an industry-level perspective. The findings reveal the following: (1) The carbon emission trading policy significantly promotes the diffusion of green technological innovation within industries, generating a robust positive technical spillover effect. (2) Mechanism analysis indicates that the policy enhances knowledge diffusion capacity and the demonstration effect within the industry, guiding enterprises toward technology sharing and synergistic innovation under competitive pressure. Moreover, a favorable institutional environment for intellectual property rights (IPR) protection positively moderates and strengthens the policy’s spillover efficiency. (3) Heterogeneity analysis demonstrates that high-tech enterprises are more sensitive to the carbon emission trading policy than ordinary firms. In terms of internal governance, the policy’s effect on augmenting innovation spillovers is more pronounced in firms characterized by the separation of the chairman and CEO roles. Consequently, it is suggested that while refining the design of carbon emission trading policies, policymakers should strengthen IPR protection and optimize corporate governance structures to establish an efficient transmission mechanism for green technology, thereby achieving a holistic low-carbon transition for the industry.