Voluntary environmental regulation and carbon information disclosure: evidence from the green factory certification in China

This study examines whether voluntary environmental regulations enhance corporate carbon information disclosure (CID), an underexplored issue in carbon governance. Based on Chinese A-share listed firms from 2010 to 2023, we use green factory certification as a quasi-natural experiment and employ a multi-period difference-in-differences approach. Data were obtained from the CSMAR and CNRDS databases. The final sample consists of 4,966 firms, yielding 40,953 firm-year observations. Results show that certification significantly improves firms’ CID. Mechanism tests reveal three channels: stronger managerial and organizational green awareness, increased investor and media attention, and promoted green investment and innovation. Heterogeneity tests indicate the effect is stronger for firms in non-high-carbon industries, non-key-polluting firms, those in regions with cash incentives and those in areas with weaker low-carbon regulation. Certified firms that receive environmental penalties do not improve CID, verifying the effectiveness of post-certification dynamic monitoring. Furthermore, certification promotes both symbolic and substantive disclosure, reduces greenwashing and cuts real carbon emissions, supporting a ‘talk-and-walk’ governance effect. Certified firms also generate positive spillover effects, motivating industry peers, city peers and downstream supply-chain customers to enhance CID. This study offers causal evidence for voluntary environmental regulation in carbon governance and implications for incentivizing credible carbon disclosure.