Patent ID: 7183920

Claim:
A system for detecting access to an article, comprising: an RFID tag; a reader located in the proximity of a vending machine, the reader detecting the RFID tag via wireless communication; a container including conductive material, the container enclosing the article, the conductive material surrounding the RFID tag and substantially preventing wireless communication between the RFID tag and the reader unless said container is opened; a memory in the RFID tag, the memory containing information associated with the article; a memory in the reader, the memory receiving the information associated with the article via wireless communication; a host computer in communication with the reader, the host computer receiving the information associated with the article from the memory in the reader; a second reader located inside the vending machine, the second reader detecting the RFID tag only if the RFID tag is placed inside the vending machine; and a second RFID tag located outside the conductive material, the wireless communication between the external RFID tag and the reader being substantially unaffected by the container being closed or open.