Abstract: A mechanism for provably disabling an electronic assembly such as a circuit board. The mechanism comprises a tab or key, normally attached to the assembly during operation, but which, when detached, prevents the assembly from being fully functional. The key may comprise a portion of the assembly. The key comprises a wire trace or other signal conductor that is severed when the key is detached from the assembly. The assembly may fail to power up if the conductor is broken, or a processing element on the assembly may detect the broken conductor and disable some or all functionality of the assembly. The key may also include an identification that can be used as evidence of the key removal.