Mandatory ESG Disclosure and ESG Rating-Record Revisions in Emerging Markets: Evidence from India’s BRSR Implementation Period

Does mandatory ESG disclosure change how rating providers revise their records? Using India’s Business Responsibility and Sustainability Reporting (BRSR) mandate, we compare large Indian firms with Chinese MSCI-rated firms in a difference-in-differences design over 2019–2024. The BRSR implementation period is associated with a large increase in MSCI rating-record revision activity (about four pre-policy standard deviations of a provider-derived index), with no detectable pre-trends and similar timing patterns across BRSR Core batches. The estimate is an India-BRSR-period large-firm differential, not a sharp threshold effect, and does not speak to rating accuracy or real ESG improvement. Regulators and ESG-rating users should monitor rating stability during disclosure rollouts.