Abstract: Some embodiments provide a method for identifying a first pattern formed by a first set of document elements. The method associates a tag that identifies the first pattern with the document. The method then identifies a second pattern formed by a second set of document elements and the tag. The method associates a second tag with the document. The second tag identifies the second pattern and is associated with a fact. Some embodiments provide a graphical user interface (GUI) for manually processing tags associated with a document. Further, different embodiments provide a system for performing iterative fact-extraction on a set of documents.