A duplication detection module may be configured to determine if data on a RFID tag is encoded. If the data on the RFID tag is not encoded, the duplication detection module may determine that the RFID tag is a duplicate RFID tag and that an item associated with the duplicate RFID tag is counterfeit. If the data on the RFID tag is encoded, the duplication detection module may cause the decoder to decode the data on the RFID tag using a private key of a receiving party as a decoding parameter. The module may check for an item identifier and a sender identifier as a part of the encoded data, determine whether the item identifier has previously been read to determine if the RFID tag was duplicated during transport and compare the sender identifier with an expected sender identifier to determine if the RFID tag was duplicated during transport.