The prospect of licensing patents that are essential to standards on an industry-wide scale is a major incentive for companies to invest in standardization activities. Most standard development organizations (SDOs) have defined intellectual property rights (IPR) policies whereby SDO members must commit to licensing their standard-essential patents (SEPs) on Fair, Reasonable and Non-Discriminatory (FRAND) terms. This study aims to provide a consistent framework for both the interpretation of FRAND commitments and the definition of FRAND royalties. Our methodology is built on the analysis of landmark and significant decisions taken by courts and competition authorities in Europe and worldwide. The purpose of the comparative analysis is to provide a comprehensive overview of how FRAND licensing terms have been defined in the evolving case law, while testing the economic soundness of the concepts and methodologies applied by courts and antitrust authorities.