ESG 공시 품질과 외부 검증은 정보 비대칭을 감소시키는가?

[Purpose]This study investigates whether the quality of ESG disclosures and the characteristics of external assurance reduce information asymmetry between firms and capital market participants. Specifically, we decompose ESG disclosure quality into content, format, and principle components and examine the differential effects of dual assurance, assurance level, and verifier type. [Methodology]The analysis is based on 405 firm－year observations of Korean listed firms that continuously published ESG－related reports between 2017 and 2022. ESG disclosure quality is quantitatively scored by dimension, and information asymmetry is proxied using stock return volatility. Multivariate regression models are employed to analyze the main and interaction effects of ESG disclosure quality and assurance attributes on information asymmetry. [Findings]The results indicate that higher ESG disclosure quality is significantly associated with reduced information asymmetry. Among the three dimensions, the format and principles of ESG disclosures play particularly critical roles. Moreover, firms that obtained multiple external assurances exhibited lower levels of information asymmetry. [Implications]Our findings highlight the importance of both improving ESG disclosure quality and enhancing external assurance mechanisms to reduce information asymmetry in capital markets. This study provides practical implications for policymakers and standard－setters aiming to establish more credible ESG reporting and assurance frameworks. It also supports the development of guidelines for standardized formats and assurance systems in ESG disclosure.