The Hitachi article says: “The [128-bit unique] number is written to the chip during the silicon fabrication process and cannot be changed.”
Me: Wanna bet? If there’s money in modifing the ID that an RFID chip broadcasts, people are going to develop the cabability. Just because something is small and burned-in at the factory does not mean that it’s secure. So once these chips are everywhere, and perhaps mandated in legal documents as the Reg article predict [a kind of high-tech stamp tax], expect new forms of fraud to develop around the implicit trust of RFID chips.