The emergence of sustainability in business has led to a growing number of market players becoming concerned about ESG rating, which includes environmental, social and governance aspects. Investors are also pricing in the scores generated by ESG indicators. The growing interest in ESG data raises the question of the reliability of the scores provided by different ESG rating agencies. This research explores the differences in the methodologies used by the most reputable ESG rating agencies through a content analysis. The inconsistency of ESG scores will be investigated by taking a random sample of companies in eight pre-selected industries and subjecting them to a correlation test. The purpose of this is to highlight the uncertainties associated with ESG ratings and to draw attention to the fact that ensuring the reliability, consistency, and transparency of ESG information remains an unresolved issue and challenge for both decision makers and users.