Systems and methods are provided for analyzing received item information for a number of items in order to determine whether each item is already included in an electronic catalog. The item information for each item may be analyzed in order to determine whether the received item information is a close match with any known item previously included in the electronic catalog. When close matches are found for one or more items, one or more modifications may be applied to at least a portion of the received item information in order to match stored item information for the corresponding close match. One or more rules associated with the determined modifications may then be generated and applied to receive item information for other items that fit certain determined criteria.