Yes, a backdoor that does not require enriching lawyers at your expense for YOUR IP.
I am looking at a backdoor that requires a PIN code at regular intervals. perhaps quarterly for registered owners or registered lessees. That PIN code works by the device producing a random hex 4 digit, which when submitted to a website (which requires the valid login supplied with each device) then returns the valid PIN code.
The user has 2 attempts to enter the PIN into the device correctly or a new random hex will be produced requiring a new PIN etc. Any registered user making attempts on the website more frequent than req'd for the same device will get flagged and a 1 day delay inserted before the next PIN request is accepted and I get an alert msg.
Then i can determine what's going on, and deny a valid PIN if I so determine, effectively disabling the (fake?) product.
Sounds workable?