The line (taunting Superman, iirc) is a play on an old Brady Bunch where someone says, "Marcia, Marcia, Marcia" but Lex according to the movie grew up in East Germany and even if he had some access to western TV he sure does not seem like the kind of guy who would have watched insipid sitcoms as a kid.
So I am guessing the writers, who had the character's bio/backstory firmly in mind, would not have had him saying this.
So did the actor come up with the line himself?
Is there any evidence one way or the other?