SDG Reporting in Spanish Listed Companies: A Longitudinal Industry‐Level Analysis Using Natural Language Processing (2018–2023)

ABSTRACT This study analyzes the evolution of Sustainable Development Goal (SDG) disclosure among IBEX 35 companies between 2018 and 2023, combining natural language processing for disclosure measurement with negative binomial generalized linear mixed models incorporating financial and governance controls. Results reveal sustained growth in disclosure volume across sectors. Adjusting for report length indicates a genuine intensification of environmental disclosure, whereas the growth in social mentions largely reflects the expansion of document volume. Only Petrol and Power, the most environmentally exposed sector, exhibits significantly higher initial environmental reporting levels, while sectors with lower initial maturity display steeper growth trajectories, consistent with competitive isomorphism. Profitability is the only financial predictor consistently associated with disclosure volume across the three dimensions, and board gender diversity is strongly associated with environmental disclosure. Negative associations between initial levels and subsequent growth suggest sector‐specific saturation in the environmental and social dimensions.