The VeriChipTM is an Radio-Frequency Identification (RFID) tag produced commercially for implantation in human beings. Its proposed uses include identification of medical patients, physical access control, contactless retail payment, and even the tracing of kidnapping victims. As we explain, the VeriChip is vulnerable to simple, over-the-air spoofing attacks. In particular, an attacker capable of scanning a VeriChip, eavesdropping on its signal, or simply learning its serial number can create a spoof device whose radio appearance is indistinguishable from the original. We explore the practical implications of this security vulnerability. We argue that: 1. The VeriChip should serve exclusively for identification, and not authentication or access control. 2. Paradoxically, for bearer safety a VeriChip should be easy to spoof; an attacker then has less incentive to coerce victims or extract VeriChips from victims' bodies.