Between 1163 and 1240 urban privileges in the county of Flanders often lack the formal characteristics typical of medieval charters. They consist solely of a list of legal articles preceded by a general heading. In Flanders, such formless law texts are traditionally known as 'keuren'. The most famous of these documents is the so-called 'Grote Keure' by which Count Philip of Alsace imposed a uniform criminal law on the major towns in his realm between 1165 and 1175. In this paper, I argue that these formless law texts are dynamic legal documents that could be updated whenever this was necessary: obsolete clauses were omitted, other passages were modified and new articles were added as time went by. At first, these changes were made to the Latin texts of the 'keuren'. In a second stage they were translated into the vernacular and these French or Dutch versions then became the basis for further changes. ; SCOPUS: ar.j ; info:eu-repo/semantics/published