  Some Ultra Diffuse Galaxies (UDGs) appear to host exceptionally rich globular
cluster (GC) systems compared to normal galaxies of the same stellar mass.
After re-examing these claims, we focus on a small sample of UDGs from the
literature that have {\it both} rich GC systems (N$_{GC}$ $> 20$) and a
measured galaxy velocity dispersion. We find that UDGs with more GCs have
higher dynamical masses and that GC-rich UDGs are dark matter dominated within
their half-light radii. We extrapolate these dynamical masses to derive total
halo masses assuming cuspy and cored mass profiles. We find reasonable
agreement between halo masses derived from GC numbers (assuming the GC number -
halo mass relation) and from cored halo profiles. This suggests that GC-rich
UDGs do {\it not} follow the standard stellar mass - halo mass relation,
occupying overly massive cored halos for their stellar mass. A similar process
to that invoked for some Local Group dwarfs, of early quenching, may result in
GC-rich UDGs that have failed to form the expected mass of stars in a given
halo (and thus giving the appearance of overly an massive halo). Simulations
that correctly reproduce the known properties of GC systems associated with
UDGs are needed.
