Three latin collections (Veronensis, Berolinensis, and Avellana) are studied in this paper, following in the tracks of the previous great works of their main German editors Otto Günther and particulary Eduard Schwartz. Some of their conclusions are questionned and new insights are offered. Veronensis, Berolinensis and Avellana are different : the period, the context of their constitution, their length and contents, and even their aims, all are diverse. Their diffusion and transmission have been varied as well. However, these three collections have special connexions with the papal archives. Moreover, they all consist of responses to a fast evolving situation from the end of the fifth century to the Justinian era. They are of great value for they present exceptional documents (one can think for instance of Gelasius’ famous letter to emperor Anastasius, written in 494), and they are subject of a highly original Fortleben. Furthermore, they still maintain some mystery, giving an opportunity for further inquiries.