CP violation in b-hadrons

Latest LHCb measurements of $CP$ violation in b-hadrons are presented based on $pp$ collision data collected in 2011 and 2012 at centre-of-mass energies of $\sqrt{s}=7$ $\rm TeV$ and $8\ \rm TeV$ respectively. The total integrated luminosity collected is 3.0 fb$^{-1}$. Results include recent measurements of $CP$ violation in $B_d$ and $B_s$ mixing, along with those of quantifying the effects of $b\to c\bar{c} s$ loop pollution. Standard Model $CP$ violation tests in loop transitions are discussed with results consistent with expectations. New decays of b-baryons are presented and preliminary studies of $CP$ violation are performed.