Based on both interviews and data, this article aims to identify the principles of justice mobilized by the designers and users of the “Boléro algorithm,” implemented in Paris-Dauphine University as early as the beginning of the 1990s. Two principles of justice structure the algorithm design and use, responding to both organizational and historical considerations: a logic of efficiency based on a meritocratic principle, on the one hand, depending on the appreciation of the individual level of the students and their supposed capacity to succeed at Dauphine; a principle of “fair balance,” on the other hand, resuming in flexible quotas aimed enabling a variety of profiles around certain parameters. Some shadow aspects of the selection are then discussed, especially the differentiation of admission rates according to the candidates’ profiles as well as the selection effect of high schools providing students.