S_4 Flavored CP Symmetry for Neutrinos

A generalized CP symmetry for leptons is presented where CP transformations are part of an $S_4$ symmetry that connects different families. We study its implications for lepton mixings in a gauge model realization of the idea using type II seesaw for neutrino masses. The model predicts maximal atmospheric mixing, nonzero ${\theta }_{13}$ and maximal Dirac phase ${\delta }_D=\pm \pi \mathrm{/}2$.