  Using magnetic field maps acquired by the Helioseismic and Magnetic Imager on
board the Solar Dynamics Observatory we measured rotation rates of 864 active
and 322 ephemeral regions observed between 2010 and 2016. We found smaller
magnetic tracers to show a tendency to rotate faster as compared to larger
ones. Thus, ephemeral regions exhibit on average the fastest rotation rate. We
further divided active regions into three classes. Class A comprised magnetic
bipoles obeying Hale's polarity law, Joy's law, and exhibiting more coherent
leading polarity in comparison with the following one. The second class B
included active regions violating at least one of the aforementioned empirical
laws. The third class U comprised unipolar active regions. We found no
significant difference between the rotation rates of active regions of classes
A and B. In contrast, unipolar active regions exhibited on average lower
rotation rate and narrower distribution of the rotation rate differences.
Assuming the rotation rate to indicate the anchoring depth of the magnetic
structure within the convection zone, we supposed that active regions of
classes A and B might be anchored throughout the entire convective envelope
while unipolar active regions a rooted within a thin layer located either near
the base of the convection zone or at a shallow near-surface depth.
