  LHCb found hints for physics beyond the standard model in $B\to
K^*\mu^+\mu^-$, $B\to K^*\mu^+\mu^-/B\to K^*e^+e^-$ and $B_s\to\phi\mu^+\mu^-$.
In addition, the BABAR results for $B\to D^{(*)}\tau\nu$ and the CMS excess in
$h\to\tau^\pm\mu^\mp$ also point towards lepton flavour (universality)
violating new physics. While $B\to D^{(*)}\tau\nu$ and $h\to\tau^\pm\mu^\mp$
can be naturally explained by an extended Higgs sector, the probably most
promising explanation for the $b\to s\mu\mu$ anomalies is a $Z'$ boson.
Furthermore, combining a 2HDM with a gauged $L_\mu-L_\tau$ symmetry allows for
explaining the $b\to s\mu^+\mu^-$ anomalies and $h\to\tau^\pm\mu^\mp$
simultaneously, with interesting correlations to $\tau\to3\mu$. In the light of
these deviations from the SM we also discuss the possibilities of observing
lepton flavour violating $B$ decays (e.g. $B\to K^{(*)}\tau^\pm\mu^\mp$ and
$B_s\to\tau^\pm\mu^\mp$) in $Z^\prime$ models.

High Energy Physics - Phenomenology;High Energy Physics - Experiment