Résumé : The value of a painting is influenced above all by the artist who created it and his reputation. Painters nowadays are easy to identify and are used to signing their artworks. But what about those whose names have not survived the test of time? This paper focuses on a particular subset of anonymous artists labelled with socalled provisional names (“Master of …”). After considering the origins and reception of the practice of creating names for unrecorded artists, we empirically investigate the market behavior of this niche segment. Based on comparative price indexes and hedonic regressions, we show that masters with provisional names have not only become autonomous brand names that are highly valued by the art market; they also outperformed named artists between 1955 and 2015. In the second phase, we analyze the provisional-name linked elements valued by the market. We find that art market participants pay attention to the creator of the provisional name, its long-term recognition and market visibility, and the typology of the names.