Voluntary ESG disclosure practices are on the rise, oftentimes not fully embracing material ESG information which is in increasing demand in the capital market. This calls for the adoption of financially material ESG disclosure standards. The SASB standards, with their clear industry-specific material disclosure guidelines, are gaining legitimacy in Korean and global markets. This study examines the disclosure integrity of ESG disclosures of the Top 10 companies listed on the KOSPI in terms of industry-specific financial materiality. We construct a coverage-ratio-scoring-mechanism by mapping Bloomberg ESG Disclosure datasets and sustainability reports to the SASB standards. The results show that 1) during 2018-2020, KOSPI Top 10 firms showed advanced industry-specific material ESG disclosure both in quantity and quality and 2) readily-available Bloomberg ESG Disclosure datasets did not fully capture the scope of the SASB-related disclosure practices of the sample firms.