With pitcher in the set position taking signs from catcher, hand at side, is the ball REQUIRED to be in the hand, or can the ball be in the glove OR hand?

Ball can be in either hand or glove.

When asking about a rule, please indicate what type of ball, High school (FED), pro and LL (OBR), etc.

In FED, either hand, hand with ball at side or behind back. OBR, both hands in front of body.

Bob

That's not right.

In FED -- the pitching hand (not necessarily the hand with the ball) must be at the side or behind the back (although "dangling" is often allowed).

In OBR, there's no restriction until the pitcher has come set (which, most often, will be after he's taken the signs).