The LSE Directory / Data providers
ISS ESG is the environmental, social and governance (ESG) research, ratings and data business of Institutional Shareholder Services (ISS), operating today inside the ISS STOXX group of companies. It supplies raw ESG datapoints, corporate, sovereign and fund ratings, climate and nature risk analytics, controversy and business-involvement screening, and regulatory-reporting datasets, delivered through its DataDesk platform, data feeds, an API and cloud access. Its ESG Corporate Rating uses a letter scale from A+ to D-, with companies that clear an industry-specific threshold awarded Prime Status. Its customers are institutional investors, asset managers, asset owners, banks and corporates that integrate ESG factors into investment policy, stewardship, portfolio monitoring and regulatory compliance. Sitting alongside ISS's separate proxy-voting and corporate-governance advisory business and, since late 2023, the STOXX and DAX index businesses, it can pair governance research with ESG scoring under one group, a bundling that stand-alone ESG rating specialists do not offer. It also publishes its rating methodologies through a public methodology library, positioning transparency of scoring logic as a differentiator against competing raters. The ESG ratings franchise descends largely from Munich-based oekom research, founded in 1993 and acquired by ISS in March 2018, then rebranded first ISS-oekom and later ISS ESG; ISS itself had already added ESG capability through the 2015 purchase of Ethix SRI Advisors and the January 2017 purchase of IW Financial, and later added CAER in February 2019. ISS as a company was founded in 1985 as a proxy advisory and governance research firm and changed hands several times since, owned by MSCI until 2014, then Vestar Capital Partners, then Genstar Capital from 2017, before Deutsche Börse Group took a majority stake in November 2020 for about 1.5 billion euros. In November 2023, ISS combined with Qontigo's STOXX and DAX index businesses to form ISS STOXX. As of year end 2025, ISS ESG's ratings cover roughly 8,200 companies, 830 sovereigns and 45,000 funds, and its DataDesk platform spans about 130,000 issuers across 13,500 factors; its stewardship-services entity, Institutional Shareholder Services Inc., is registered as an investment adviser with the US Securities and Exchange Commission. ISS STOXX's 2026 Global Outlook Report, published in mid-2026, is a recent example of its research output: it found only 17 percent of companies analyzed showed both climate transition readiness and strong governance, flagged low corporate disclosure of labor metrics such as living wages, and noted sustainable ETF assets had reached 631 billion dollars, up 18 percent since December 2024.
