Necessary conditions for the diagonalizability of Maxwell's equations in inhomogeneous and fully bi-anisotropic media

Considering inhomogeneous and fully bi-anisotropic media necessary conditions have been identified for the diagonalizability of Maxwell's electrodynamic equations. The same conditions also permit the construction of a system of equations supplementing the diagonalized (D) equations. The combined D- and the associated supplementary (S) equations are sharply equivalent with the originating Maxwell's equations, a fact which ascertains the internal consistency of the derived D- and S forms.