International organisations are considered central actors in global education governance, producing policy-relevant knowledge that can shape national reforms. While extensive studies have examined their influence on education policy, less attention has been paid to who actually produces this knowledge. This article examines the producers of global education policy knowledge by analysing the authorship of education-related publications of UNESCO, the OECD, and the World Bank. Drawing on the theoretical concepts of policy networks and epistemic communities, the study dissects patterns of disciplinary backgrounds, institutional affiliations, and geographic locations of authors. Based on an analysis of 1,447 publications and 3,175 authors, the findings reveal limited overlap across organisations, distinct disciplinary profiles, a strong reliance on internal contributors, and a predominance of authors affiliated with institutions in the Global North. These patterns reflect organisational mandates and knowledge infrastructures, and point to epistemic segmentation that shapes how policy knowledge on global education problems and solutions is legitimised.