This study examines the economic consequences of China’s tiered regulatory enforcement system, which functions as a real-world “enforcement pyramid” (Ayres and Braithwaite, 1992). We analyze the differential impacts of low-tier exchange inquiry letters, mid-tier CSRC warning letters, and high-tier formal administrative penalties on listed firms from 2014 to 2023. Using an event study methodology, we find that market reactions are graded according to the pyramid’s hierarchy, with formal penalties eliciting the most severe negative stock returns, followed by warning letters, and then inquiry letters. Notably, even the lowest-tier inquiry letters trigger a significant negative market reaction, indicating they convey value-relevant information (Chen, Li, and Sougiannis, 2021). Employing a propensity score matching and difference-in-differences (PSM-DiD) approach, we document significant real effects. Both inquiry and warning letters lead to subsequent improvements in financial reporting quality and reductions in corporate investment. Consistent with deterrence theory, the disciplinary effect on reporting quality is significantly stronger for firms receiving the more formal CSRC warning letters. Our findings provide robust evidence for the effectiveness of responsive regulation in capital markets and offer crucial insights for regulators, investors, and corporate managers in emerging economies (Piotroski and Wong, 2012).

Keywords：Regulatory Enforcement, Enforcement Pyramid, China, Market Reaction, Corporate Governance