  We conduct a model-independent effective theory analysis of hypercharged
fields with various spin structures towards understanding the diboson excess
found in LHC run I, as well as possible future anomalies involving $WZ$ and
$WH$ modes. Within the assumption of no additional physics beyond the standard
model up to the scale of the possible diboson resonance, we show that a
hypercharged scalar and a spin 2 particle do not have tree-level $WZ$ and $WH$
decay channels up to dimension 5 operators, and cannot therefore account for
the anomaly, whereas a hypercharged vector is a viable candidate provided we
also introduce a $Z'$ in order to satisfy electroweak precision constraints. We
calculate bounds on the $Z'$ mass consistent with the Atlas/CMS diboson signals
as well as electroweak precision data, taking into account both LHC run I and
II data.
