A Radio Frequency Identification (RFID) system that tracks tags in real-time based on EPC codes and on other priority codes written into transponder memory fields of the tags. As an example, a priority code may be written into a memory of an RFID transponder identifying a high-value item or a small high-value...http://www.google.co.uk/patents/US7952480?utm_source=gb-gplus-sharePatent US7952480 - RFID tag filtering and monitoring
