  The group invariance of entanglement is obtained within a very general and
simple setup of the latter, given by a recently introduced considerably
extended concept of tensor products. This general approach to entanglement -
unlike the usual one given in the particular setup of tensor products of vector
spaces - turns out not to need any specific algebraic structure. The resulting
advantage is that, entanglement being in fact defined by a negation, its
presence in a general setup increases the chances of its manifestations, thus
also its availability as a resource.
