  Concurrence is an entanglement measure characterizing the {\it mixed} state
bipartite correlations inside of a pure state of an $n$-qubit system. We show
that after organizing the charges and the moduli in the STU model of $N=2$,
$d=4$ supergravity to a three-qubit state, for static extremal spherically
symmetric BPS black hole solutions the vanishing condition for all of the
bipartite concurrences on the horizon is equivalent to the attractor equations.
As a result of this the macroscopic black hole entropy given by the
three-tangle can be reinterpreted as a linear entropy characterizing the {\it
pure} state entanglement for an arbitrary bipartite split. Both for the BPS and
non-BPS cases explicit expressions for the concurrences are obtained, with
their vanishing on the horizon is demonstrated.
