This article reconsiders all the additions and marginalia and some of the reader marks in the Cathar manuscript J II 44 held by the National Central Library of Florence (Firenze, Biblioteca nazionale centrale, Conventi soppressi, ms. J II 44, also known under the shelf mark I II 44), revises the identification of scribal hands, and draws some conclusions concerning the genesis of the codex. The additions and reader marks, underestimated and partly misinterpreted in Antoine Dondaine's, Arno Borst's and Christine Thouzellier's classical presentations of the manuscript and in Dondaine's and Thouzellier's editions of the main works it contains, are in fact important evidence of further use of the manuscript. Careful reassessment of the reader marks and additions shows that they do not come from an inquisitorial environment as Borst and Thouzellier argued for some of them, but mostly point to the context of Lombard Catharism in the mid-thirteenth century. The additions exhibit at least two rather unexpected strands in the thought of the scribes/readers of the compilation, the first being moralistic and sapiential, the second, apocalyptic. Finally, a reconsideration of the content suggests (1) disconnecting the part "On Striking the Shepherd" from the part "On Persecution", which helps partly to resolve an important codicological issue concerning the composition of the manuscript, and (2) disconnecting both of these parts from the Liber de duobus principiis proper and drawing it nearer to later additions and marginalia in the codex.