Around 1520, Jean Valier, a Piedmontese in the service of the bishop of Agen, compiled 158 papal bulls, mainly those obtained by a previous bishop in 1309 from his nephew, Pope Clement V. They validate and confirm 878 original acts (mainly cessions of tithes by laymen around 1240-1290). They empty and confirm 878 original acts (mainly cessions of tithes by laymen around 1240-1290), and judging by the few preserved originals and modern copies Valier gives a faithful analysis. These texts show the strengthening of episcopal power in the 13th century in a diocese where micro-parishes abound. Alleutists, well-to-do peasants or small lords who had from time immemorial possessed tithes mixed with their seigniorial income, handed over to the bishop rights that had been pulverised through inheritance. For a long time, historiography has described these transfers as ‘restitutions’, a term that is absent from the originals and the bullary: they were cessions and not always without consideration. These acts provide us with information on the Church, secular society, and family ties in the Agen region in the second half of the 13th century, and on the functioning of the episcopal chancellery from the Middle Ages to the Revolution.