  Evidence of CP violation in the charm sector has been observed recently by
the LHCb and CDF Collaborations. The issue of whether it can be accommodated
within the standard model (SM) is examined in this talk. We conclude that the
CP asymmetry difference $\Delta a_{CP}^{\rm dir}$ between $D^0 \to K^+ K^-$ and
$D^0 \to \pi^+ \pi^-$ is of order $-(0.14\sim 0.15)%$. If the improved
theoretical estimate of $\Delta a_{CP}^{\rm dir}$ in the SM remains to be a few
per mille and the experimental measurement continues to be large with more
statistics in the future, it will be clear evidence of physics beyond the SM in
the charm sector.
