1. A system for classifying documents via propagation, comprising: a text identification module to identify within at least one document, text that is highlighted by a user, wherein the document is associated with a classification code based on the highlighted text; a comparison module to compare at least a portion of the highlighted text with one or more unclassified documents; a same document identification module to identify those unclassified documents with text that is the same as the compared portion of the highlighted text in the document; a classification assignment module to automatically assign the classification code of the document to the identified unclassified documents with text that is the same; a similar identification module to identify those unclassified documents with text that is similar to the compared portion of the highlighted text in the document; and a distribution module to provide the unclassified documents with similar text to the user for review and classification.