1. A system comprising: at least one database; at least one processor implemented at least partially by hardware; and a memory including instructions that, when executed by the at least one processor, cause the at least one processor to: retrieve, from the at least one database, at least one independent claim of a patent as issued; retrieve, from the at least one database, at least one independent claim of the corresponding patent application as published; automatically compare the at least one issued independent claim of the patent to the at least one published independent claim of the patent application to identify at least one unique keyword present in the at least one issued independent claim but not present in the at least one published independent claim; cross-reference, using the at least one processor, the at least one identified unique keyword to a passage in the specification of the issued patent, wherein the at least one identified unique keyword is cross-referenced to the passage in the specification of the issued patent using input received from a user interface; identify a first prior art document and a second prior art document; calculate an overlap score for the first prior art document based on at least one occurrence of the at least one unique keyword in the first prior art document; calculate an overlap score for the second prior art document based on at least one occurrence of the at least one unique keyword in the second prior art document; calculate a ranking for the first prior art document by comparing the calculated overlap score of the first prior art document to the calculated overlap score of the second prior art document; and display, in the user interface, a graphical representation of the calculated overlap score of the first prior art document and a graphical representation of the calculated overlap score of the second prior art document based on the calculated ranking, and the passage in the specification of the issued patent.
3. The system of claim 1 , wherein the instructions to cross-reference the at least one unique keyword to the passage in the specification of the issued patent include instructions to use a pool of synonyms for the at least one unique keyword.