Abstract: The essay assesses all the regulations in these collections that relate directly or indirectly to Jews, dividing them into four topic-based groups (protection and toleration; the mission of the Jews; proselytism; reduction of rights and condemnation) each with further subdivisions. This provides a solid foundation for comparing the treatment of Jews advocated by Burchard and Ivo, as well as for comparing their propositions with those of other canon law collections. Since older systematic canonical regulations for Jews apparently did not serve as immediate examples for either Burchard or Ivo, whereas the latter had an influence on Gratian, it can be assumed that Burchard’s collection formed the beginning of a direct line of canon law developments for Jews. If we compare Burchard’s and Ivo’s regulations we notice a clear negative progression in the treatment of Jews between the former and the latter, even though Ivo, in principle, also advocated the protection of Jews. With either it becomes apparent, however, that the great majority of the later canonical regulations for Jews trace back to the distant past. Moreover, the comparison of Ivo’s Decretum with the Panormia , a work attributed to him, reveals so many differences in the fundamental attitude towards Jews that the Panormia may have to be attributed to another author, possibly from Ivo’s school.