  We construct families of optimal Hardy-weights for a subcritical linear
second-order elliptic operator $(P,B)$ with degenerate mixed boundary
conditions. By an optimal Hardy-weight for a subcritical operator we mean a
nonzero nonnegative weight function $W$ such that $(P-W,B)$ is critical and
null-critical with respect to $W$. Our results rely on a recently developed
criticality theory for positive solutions of the corresponding mixed boundary
value problem.
