Industrial–Financial Integration Policy and Corporate Sustainability: Asymmetric Effects and the Boundary Role of Green Transformation

Corporate sustainability requires firms to balance financial performance and social responsibilities, yet whether institutional support policies generate consistent sustainability outcomes remains unclear. This study exploits China’s industrial–financial cooperation (IFC) pilot policy as a quasi-natural experiment, using A-share listed firms from 2011 to 2024 and difference-in-differences (DID) design to examine its effects on corporate sustainability performance. The baseline two-way fixed effects (TWFE) estimates show a significant positive association between the IFC policy and financial performance (ROE), while the average effect on environmental, social, and governance (ESG) performance is statistically insignificant. The positive ROE association remains qualitatively similar across conventional robustness checks but becomes statistically insignificant when treatment-effect heterogeneity under staggered adoption is explicitly accounted for, whereas the insignificant ESG response remains consistent across estimators. Mechanism analysis provides evidence consistent with two potential transmission pathways: resource allocation efficiency and the operating-cost pathway. While significant indirect associations are identified through these pathways, the overall policy effect on ESG remains insignificant. Further analysis shows that green transformation is positively associated with corporate sustainability but may weaken the policy–performance relationship through transitional resource pressures and competing resource demands. These findings provide new insights into how institutional support policies and green transformation jointly shape corporate sustainability transitions.