THE SITUATION OF SUSTAINABLE DEVELOPMENT GOALS IN IBEX-35 ORGANIZATIONS

The Sustainable Development Goals (SDGs) offer a structured framework for companies to promote sustainable development through responsible practices aligned with global demands. The companies that make up the IBEX-35, Spain's main stock index that brings together the country's leading companies, have played a crucial role in incorporating the SDGs into their strategies and operations (GRI, 2021). However, accurately assessing these commitments is challenging, due to the subjective nature and variability of the information typically presented in sustainability reports (UNGC, 2021). Fuzzy logic is a suitable tool to address this uncertainty (Zadeh, 1965), providing flexible interpretation of both qualitative and quantitative data in these reports (Kaufmann y Gil-Aluja (1987, 1988)). This study analyzes how IBEX-35 companies integrate, apply and communicate the SDGs in their sustainability reports. In this analysis, fuzzy logic is used to manage the uncertainty inherent in the evaluation of its progress, by facilitating a more precise representation of ambiguity in the sustainability evaluation, helping to measure corporate commitments in a more detailed way. This analysis reviews the priority SDGs in the 2023 reports and assesses commitment using a scale adapted to the uncertainty of the data. The results allow us to identify patterns of implementation of the SDGs and differences between sectors, highlighting the need for adaptive approaches in sustainability.