Does the construction of ecological civilization institution system promote the green innovation of enterprises? A quasi-natural experiment based on China's national ecological civilization pilot zones.

Enhancing green innovation is fundamental for constructing China's new ecological civilization era and participating in the global green industrial revolution. Therefore, it is necessary to improve the green innovation of the enterprises by enhancing the ecological civilization institution system. This study assesses the impact of China's ecological civilization institution system on green innovation, taking the establishment of the National Ecological Civilization Pilot Zone (NECPZ) as a quasi-natural experiment and the non-financial listed firms in China's A-share market from 2010 to 2019 as the research objects. A time-varying difference-in-differences approach is adopted to evaluate the effectiveness of the pilot policy. It is found that the pilot policy has promoted green innovation in the treatment group. The results are proven valid after a series of robustness tests. Heterogeneous impacts of the ownership and industry are also discussed, finding a more substantial effect on the non-state-owned enterprises and firms in non-heavy polluting industries. Furtherly, it is found that the policy implementation has suppressed firms' total factor productivity but has improved local environmental performance. Based on the above results, a series of policy recommendations are put forward.