Intellectual legacies are part of historians’ concerns, when they study the evolution of ideas. There are, however, no guidelines to help characterize the reception of intellectual legacies. This article provides preliminary tools to fill this gap, with a typology (faithful, formal, substantial legacies), and with two criteria to assess the conformity between the heir’s and her inspirer’s proposals. The objective is not to judge the legitimacy of this or that reception, but to facilitate its characterization, for a better understanding of the transmission of ideas. One case study from the history of economic thought, Nicholas Georgescu-Roegen’s bioeconomics and its legacies, is provided to illustrate the operability of the toolbox.