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374Since the reform and opening up, China’s economy has achieved rapid growth. However, the prolonged reliance on a traditional economic growth model characterized by high energy consumption and heavy pollution has also engendered excessive resource depletion and mounting ecological and environmental pressures. Against this backdrop, green innovation has become a crucial pathway for firms to gain sustainable competitive advantages and achieve high-quality development. As a financial instrument specifically designed to support environmentally friendly projects, what role do green bonds play in promoting corporate green innovation? From the perspective of supply chain networks, do green bond issuances by suppliers or customers generate a spillover effect on focal firms’ green innovation?
Based on data from A-share listed companies in Shanghai and Shenzhen from 2007 to 2023, this paper investigates the impact of green bond issuances on corporate green innovation, with a particular focus on revealing the spillover effect transmitted through supply chain networks and the underlying mechanisms. The results show that green bond issuances effectively enhance corporate green innovation capabilities, and generate an innovation spillover effect through interaction and feedback mechanisms among upstream and downstream firms within the supply chain. Specifically, strengthening of trade credit, optimization of investor structures, and green transformation serve as key mechanisms through which green bond issuances by suppliers or customers promote focal firms’ green innovation. In particular, the innovation spillover effect is more pronounced among non-SOEs and firms with higher information disclosure quality.
The marginal contributions of this paper are threefold: First, it extends beyond the single-firm study of bond issuers by adopting a supplier and customer perspective within the supply chain, and systematically investigates the potential impact of green bond issuances by suppliers or customers on focal firms’ green innovation, providing direct empirical evidence for the supply chain network externalities of green bond issuances. Second, it dissects the underlying mechanisms through which green bond issuances by suppliers or customers affect focal firms’ green innovation, offering a clearer interpretation of the transmission mechanisms of green finance within the supply chain. Third, it examines the heterogeneous characteristics of the green bond supply chain spillover effect from the perspectives of ownership type and information environment, which not only furnishes structural evidence for understanding the multi-level roles played by different types of firms in the green finance transmission chain, but also provides a scientific basis for policymakers to formulate more targeted green finance policies.
