Constraints on CP violation by a non-minimal higgs sector from CP-conserving processes

Limits on the charged Yukawa couplings obtained from CP-conserving processes involving B-mesons provide strong constraints on CP violation by a non-minimal scalar sector. In the framework of the Weinberg three-Higgs-doublet model these constraints are compared with direct limits on CP violation by charged scalars obtained from their potential contribution to the neutron electric dipole moment and are found to be equally useful. The possibility of spontaneous CP violation in the Weinberg model is also discussed and shown to be ruled out by the new constraints for any values of the charged scalar masses.