The Impact of Environmental, Social, and Governance Disclosure on the Firm Value of Non-Financial Firms Listed in South Africa

This study examines the impact of Environmental, Social, and Governance (ESG) disclosures on the firm valuation of non-financial firms listed in South Africa, using Tobin’s Q as a firm value proxy. Using a panel data approach of 642 firm-year observations from 2017 to 2022, the study applies Fixed Effects, Random Effects, and Generalized Method of Moments (GMM) estimators to address possible endogeneity concerns. The results consistently show that, for the whole sample, ESG disclosures are positively and significantly related to firm value, thus supporting the view that markets reward transparency and sustainability initiatives. Firm size and liquidity also have positive impacts, while financial leverage has an inverse relationship with firm value. Subgroup regression analysis shows significant sectoral differences: ESG disclosure in non-manufacturing companies has a positive and significant relationship with firm value, in line with stakeholder and signaling theories, emphasizing the premium for intangible assets like reputation and trust. However, in manufacturing companies, ESG disclosure is negatively and significantly associated with firm value, implying concerns among investors regarding compliance costs, strategic misalignment, or possible “greenwashing.” The study contributes to the emerging-market literature by (i) introducing a PCA-based ESG index specific to JSE-listed non-financials, (ii) triangulating results across static and dynamic specifications to ensure robustness, and (iii) uncovering sectoral heterogeneity that has been largely overlooked. The research also has practical implications for corporate managers, policymakers, and investors on the alignment of ESG practices to industry attributes for long-term value optimization.