The disclosure of the materiality process in sustainability reporting by Spanish state-owned enterprises

PurposeThis paper aims to assess the disclosure of the materiality process in the preparation of sustainability reports of state-owned enterprises (SOEs). This paper also explores the effects of regulation mandating that SOEs prepare sustainability reports. In the specific case of port authorities, the study analyses the influence of a sector guideline that determines what should be included and the structure of the report. Another aim of this paper is to delve into SOE's motivations for disclosing information on materiality assessments, using the assumptions of the different theories to explain their reporting practices.Design/methodology/approachUsing a sample of SOEs sustainability reports, a content analysis is undertaken. The methodology involves the analysis of the information disclosed by SOEs in Spain and the development of a materiality disclosure index. This index enables sampled entities to be classified on a scale of 0–5, based on the extent of their disclosures of the materiality determination process. This study also identifies several variables that explain differences in these disclosures.FindingsA low rate of information disclosed about the materiality process can be attributed to the desire of SOEs to create symbolic legitimacy. In a context where the disclosure of sustainability information is mandatory, only few organisations apply the principle of materiality to define the content of their sustainability reports. These results highlight that institutional isomorphism has only had a limited effect on the materiality process.Research limitations/implicationsLimitations associated with the sample size and composition of the sample by sector apply.Practical implicationsThis research shows that generally accepted reporting guidelines constitute a reference framework for sustainability reporting but that the principles underpinning these frameworks are not always implemented.Originality/valueThis study extends the literature on the implementation of the principle of materiality and uses disclosure theories to explain the actual reporting by SOEs of their materiality process.