Research on the Impact of Corporate ESG Performance on Supplier Concentration in Chinese Manufacturing Firms

The global division of labor system is increasingly refined, and the core components of some manufacturing enterprises are concentrated in a few (or even a single) suppliers, resulting in supply dependence. Excessive concentration of suppliers can lead to a higher risk of supply chain disruption. To this end, taking manufacturing companies listed on the Shanghai and Shenzhen A-share markets in China from 2010 to 2024 as samples and referring to Huazheng ESG rating data, research shows how the ESG performance of manufacturing companies reduces supplier concentration. The research found that (1) the ESG performance of manufacturing enterprises significantly reduces supplier concentration,—this effect is mainly reflected in social responsibility (S dimension)—and firm size has a positive moderating effect; (2) ESG performance has a mediating effect of alleviating financing constraints and enhancing trade credit in the process of reducing supplier concentration; and (3) heterogeneity analysis results show that the inhibitory effect of ESG performance on supplier concentration is more significant in non-state-owned enterprises. Through empirical analysis, the research scope of ESG performance was expanded to the upstream supply chain field, emphasizing the importance of ESG performance in manufacturing enterprises and providing theoretical and empirical evidence for enterprises to achieve high-quality and sustainable development.