From the ever interesting forums at http://www.gamingfloor.com In a thread titled "Counterfeit Chips", Ian the admin provides a link and quote from GPIC http://biz.yahoo.com/bw/050329/295650.html?.v=1

From Gerard's mouth:

While RFID-embedded casino chips do not provide 100% security, since they can, in theory, be duplicated, the protection of our chip tracking systems blahblahblah

So wonder how long before one of the casinos find themselves with a cruddy looking fake that the Big Bucks WhizBang $ystem sez is A-Okay?