A technique for content management using group rights is described. The technique facilitates a flexible management for a group of content files mainly by effecting a change of group memberships for subsets of the group and a partial update of the content files. As one aspect, a content file manager (20) is provided to create content files associated with group rights. A device (21) is also provided to process such content files. One method aspect comprises assigning a plurality of content items to a new group whose identifier is associated with a new group rights object; determining if any of the content items has been previously distributed; and for each previously-distributed content item, creating an update content file including the group identifier of the new group and excluding the previously-distributed content item itself.