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Some Ultra Diffuse Galaxies (UDGs) appear to host exceptionally rich globularcluster (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 theliterature that have {\it both} rich GC systems (N$_{GC}$ $> 20$) and ameasured galaxy velocity dispersion. We find that UDGs with more GCs havehigher dynamical masses and that GC-rich UDGs are dark matter dominated withintheir half-light radii. We extrapolate these dynamical masses to derive totalhalo masses assuming cuspy and cored mass profiles. We find reasonableagreement between halo masses derived from GC numbers (assuming the GC number -halo mass relation) and from cored halo profiles. This suggests that GC-richUDGs do {\it not} follow the standard stellar mass - halo mass relation,occupying overly massive cored halos for their stellar mass. A similar processto that invoked for some Local Group dwarfs, of early quenching, may result inGC-rich UDGs that have failed to form the expected mass of stars in a givenhalo (and thus giving the appearance of overly an massive halo). Simulationsthat correctly reproduce the known properties of GC systems associated withUDGs are needed.

Do Ultra Diffuse Galaxies with Rich Globular Clusters Systems have Overly Massive Halos?