A computer-implemented method is presented herein. The method obtains a first content item from an online source, and then generates a characterizing signature of the first content item. The method continues by finding a previously-saved instance of the characterizing signature and retrieving data associated with a second content item (the second content item is characterized by the characterizing signature). The method continues by analyzing the data associated with the second content item, corresponding data associated with the first content item, and decision criteria. Thereafter, either the first content item or the second content item is identified as an original content item, based on the analyzing. The other content item can be flagged as an aggregated content item.