Artificial Intelligence Pilot Zones and Sustained Green Innovation: Evidence from Chinese Manufacturing Firms

This paper examines whether China’s National New Generation Artificial Intelligence Innovation and Development Pilot Zone program (AI pilot zones) strengthens Persistence-Weighted Green Invention index (PWGI) among listed manufacturing firms. We link 36,287 firm-year observations from 2006 to 2024 to staggered city-level pilot-zone approvals and define effective exposure two fiscal years after approval. In a firm-level DID design with firm and industry-year fixed effects, effective exposure raises PWGI by 3.57 index units. Event-study estimates show no differential pre-trends, and the result is robust to alternative outcomes, concurrent-policy controls, placebo tests, common-support restrictions, and spatial-interference diagnostics. Mechanism and heterogeneity evidence points to AI capability accumulation and stronger responses among firms better able to use local policy platforms. The findings suggest that place-based AI infrastructure can support durable green innovation rather than only short-run patenting.