A device is described for forming a signature from an input signal (input). According to the present invention, a plurality of transformation elements is provided, each having a finite-state machine, to which, on the input end, in each case the input signal (input) and/or a signal (input′), that is a function of the input signal, is able to be fed, all the finite-state machines are similar and are configured in such a way, particularly able to be initialized, that each finite-state machine always respectively has a different state than do all the other finite-state machines, and the signature is formable as a function of state data of at least one finite-state machine.