  We summarize our analysis for the vacuum stability of the superweak extension
of the standard model. The parameter space allowed by the $W$-boson mass
measurements and collider searches for a new scalar particle are also
presented. The final result is a well defined non-vanishing portion of the
parameter space, where the vacuum is stable, the couplings are perturbative and
is not excluded by $W$ mass measurements and collider searches.
