Sustainability Report of Mining and Energy Companies: The Role of Board Characteristics and Public Ownership

Abstract

Sustainability reporting has become an important mechanism for strengthening corporate accountability, particularly in environmentally sensitive industries such as mining. In Indonesia, increasing regulatory requirements and stakeholder expectations have intensified the need to understand how corporate governance mechanisms influence sustainability reporting disclosure (SRD). This study examines the effects of board size, board independence, and public ownership on SRD among mining companies listed on the Indonesia Stock Exchange during 2019–2023. Using a quantitative approach, the study applies panel data regression to a purposively selected sample of 53 companies that consistently published the required corporate reports during the observation period. SRD was measured using a disclosure index based on the Global Reporting Initiative Standards. Board size, board independence, and public ownership were included as the main explanatory variables, while firm size, leverage, and profitability were incorporated as control variables. The Fixed Effects Model was selected as the most appropriate estimation method. The descriptive results show an average SRD level of 41.5%, indicating that Indonesian mining companies disclosed fewer than half of the sustainability indicators assessed. The regression results demonstrate that board independence and public ownership have significant positive effects on SRD, whereas board size has no significant effect. These findings suggest that the effectiveness of independent monitoring and external shareholder oversight is more influential in promoting sustainability transparency than the numerical size of the board. The results support agency-theoretic arguments that independent governance and dispersed ownership reduce information asymmetry and strengthen managerial accountability. Practically, mining companies should enhance the substantive role of independent commissioners, strengthen board-level sustainability oversight, and improve disclosure responsiveness to public shareholders to increase reporting credibility and stakeholder confidence.