The formal legal definition of deprivation of custody or visitation under California Penal Code 278.5 is as follows: You took, enticed away, kept, withheld or concealed a child; The child was under the age of eighteen (18); and In doing so, you maliciously deprived a lawful custodian of his/her right to custody of the child, or deprived a person of a lawful right to visitation with the child.