A computer-implemented system and method for visually suggesting classification for inclusion-based document cluster spines are provided. A set of reference documents each associated with a classification code is designated. A different set of un-coded documents is obtained. One or more of the coded reference documents are combined with a plurality of un-coded documents into a combined document set. The documents in the combined document set are grouped into clusters. The clusters are organized along one or more spines, each spine including a vector. A visual suggestion for assigning one of the classification codes to one of the spines is provided, including visually representing each of the reference concepts in the clusters along that spine.