Patent ID: 8447985

Claim:
A watermarking apparatus for an electronic circuit, comprising: a watermark memory operative to store a watermark characterizing said electronic circuit; and a watermarking signal generator operative to generate based on said watermark a watermarking signal on a power supply line of said electronic circuit, wherein said watermarking signal is detectable for a recognition of said watermark; wherein said electronic circuit is operative to change into a watermarking signal generation mode based on a given event and wherein said watermarking apparatus further comprises: a watermarking signal control, operative to initiate said generation of said watermarking signal by said watermarking signal generator when said electronic circuit is in, or changes into, said watermarking signal generation mode; and wherein said watermark memory or said watermark signal generator is part of a functional logic of said electronic circuit when said electronic circuit is in another mode than the watermarking signal generation mode.