Spectroastrometric vs. stellar mass for AMAZE and LSD objects. Filled circles and open diamonds corresponds to objects classed as “rotating” and “unclassified” respectively, and the spectroastrometric masses have been computed for a disk inclination of 60deg. The vertical bars show the effect on M_spec of extreme disk inclinations of 90° and 10° (lower and upper values respectively). The gray area is the region of unphysical M _⋆  > M_spec. Brown dashed lines represents respectively the 30%, 60% and 90% gas fraction loci. Only the “unclassified” objects have dynamical masses (M_spec) significantly lower than the corresponding stellar masses.