To provide a print data processing system, a printer, and a data processing indicating apparatus, for storing print data and a print history and notifying update of the print data, which is not necessarily registered separately in order to receive a notification of update. The printer stores name data of print data, identification data of a data processing indicating apparatus (or an external apparatus) that has sent storage indicating data of the print data, and identification data of a data processing indicating apparatus (or an external apparatus) that has sent print indicating data of the print data; judges if the print data is updated or not on the basis of the stored data; and notifies each data processing indicating apparatus (or the external apparatus) that has sent print indicating data of the print data of update of the print data.