The Forward Citation Generator takes a target U.S. patent and retrieves the patent numbers of all subsequently granted U.S. patents that cite the target patent (the target patent's "forward citations"). Those forward citations of the target patent are the 1st Generation forward citations. The number of 1st Generation forward citations of a target patent is considered to be a rough measure of the importance of the invention claimed in the target patent.
The Forward Citation Generator can then go through an iterative process of retrieving the forward citations for each 1 st Generation forward citation to obtain the 2nd Generation forward citations, and then go through the same process to obtain the 3rd Generation, 4th Generation, etc. forward citations until it reaches the point where there simply are no further forward citations (users can manually limit the number of generations, if they wish, to a number from one to fifteen).
Once the last generation is reached, the Forward Citation Generator will download the text of every patent that was cited and extract basic bibliographic data (issue date, assignee, title and main class/subclass). The main class/subclass numbers are supplemented with the full description of that class/subclass (a text file that comes with the Forward Citation Generator provides the descriptions).