XBRL 도입이 주가동조성에 미치는 영향

This study examines the impact of XBRL adoption on stock return synchronicity. It is expected that XBRL-based financial reporting will reduce investors’ information processing costs, thereby mitigating information asymmetry between firms and investors. From this perspective, this study analyzes the relationship between XBRL adoption and stock return synchronicity using the firms listed on KOSPI from 2011 to 2021. The analysis results are as follows. First, stock return synchronicity increased in the post- XBRL period; however a higher ratio of standard tags attenuated this increase in post-XBRL period. These results suggest that the effectiveness of XBRL in enhancing information eff iciency depends on the quality of XBRL rather than XBRL adoption itself. Next, the study examines whether the effects of XBRL adoption differ by investors’ ex-ante information processing costs. The results indicate that the negative impact of the standard tag ratio on stock return synchronicity in the post-period is more pronounced for firms with higher foreign ownership. This implies that XBRL adoption enhances the information efficiency of sophisticated investors but not retail investors. This study extends prior research on XBRL by examining its effects on the capital market. Furthermore, the findings that the impact of XBRL differs among investors suggest the information asymmetry among investor groups and indicate further improvements in the implementation of XBRL are needed. Additionally, it sheds light on the effectiveness of XBRL-based reporting under the IFRS regime, providing a basis for future studies.