Baseball Interference: Batter's Role & Rules

Question
Runner is on second, stealing third.  My catcher goes to throw the runner out, but the batter had stepped back with one foot in and one foot out of the batter's box.  The ball hits the bat.  Should the batter be out?

Answer
Yes.  The batter can not do anything to interfere with the catcher's ability to make a throw to a base.  Any movement by the batter that restricts the catcher in anyway is interference and the batter shall be out and the runners sent back to their bases at the time of pitch.