摘要：在加快经济社会发展全面绿色转型的政策背景下，识别环境保护税在供应链上对企业绿色技术创新的全面政策效应，有利于我国经济的可持续发展以及新质生产力的培育。本文基于《中华人民共和国环境保护税法》的实施，构建多时点双重差分模型，着重考察了环境保护税政策的实施对企业绿色技术创新的直接影响及其在供应链中的溢出效应。研究发现:环境保护税政策通过成本遵循效应显著“挤出”了企业自身的绿色技术创新活动，表现为绿色专利申请量的下降。供应链分析表明，环境保护税对上下游企业产生非对称影响，即受环境保护税影响的下游企业通过需求拉动和提供商业信贷促进中游企业绿色技术创新，而受环境保护税影响的上游企业对中游企业绿色技术创新的影响并不显著。异质性分析表明，这种溢出效应在不同股权集中度、不同行业污染程度的企业间存在显著差异。本文为评估环境保护税政策的绿色转型效应提供了更加全面的视角和证据，有助于认识供应链关系在环境保护税影响企业绿色技术创新中所能发挥的作用，为协同推进上中下游企业绿色发展的政策安排提供启示。
关键词：环境保护税；供应链；绿色技术创新；溢出机理
Environmental Protection Tax and Green Technological Innovation: Evidence from Asymmetric Spillovers along the Supply Chain
Yan Zheming, Gao Yidan, Zhu Danfeng
Abstract: Against the backdrop of China’s accelerated green transformation of economic and social development, identifying the comprehensive effects of the Environmental Protection Tax on enterprises’ green technological innovation along the supply chain is essential for promoting green and sustainable growth and fostering new productive forces. Exploiting the implementation of the Environmental Protection Tax Law of the People’s Republic of China, this paper constructs a multi-period difference-in-differences (DID) model to systematically examine both the direct impact of the Environmental Protection Tax on enterprises’ green technological innovation and its spillover effects along the supply chain. The results show that, first, the policy significantly crowds out enterprises’ green technological innovation through a cost-compliance effect, as evidenced by a simultaneous decline in the total number of green patents. Second, supply chain analysis reveals pronounced asymmetric effects across upstream and downstream firms. Downstream enterprises stimulate green technological innovation among midstream firms through demand-pull mechanisms and the provision of trade credit, whereas the tax burden–shifting behavior of upstream firms weakens this transmission channel. Third, heterogeneity analysis indicates that these spillover effects vary significantly across firms with different ownership concentration structures and levels of industrial pollution intensity. This paper offers a more comprehensive perspective and empirical evidence for evaluating the green transformation effects of the Environmental Protection Tax, deepens the understanding of the role of supply chain linkages in shaping firms’ green technological innovation responses, and provides policy-relevant insights for coordinating environmental taxation with the green and low-carbon transformation of industries.
Keywords: Environmental Protection Tax; Supply Chain; Green Technological Innovation; Spillover Effects
