  The bulk band structure of the topological insulator \sbte~ is investigated
by angle-resolved photoemission spectroscopy. Of particular interest is the
dispersion of the uppermost valence band with respect to the topological
surface state Dirac point. The valence band maximum has been calculated to be
either near the Brillouin zone centre or in a low-symmetry position in the
$\bar{\Gamma}-\bar{M}$ azimuthal direction. In order to observe the full energy
range of the valence band, the strongly p-doped crystals are counter-doped by
surface alkali adsorption. The data show that that the absolute valence band
maximum is likely to be found at the bulk $\Gamma$ point and predictions of a
low-symmetry position with an energy higher than the surface Dirac point can be
ruled out.
