[just another ref]

Years ago, setting a moving screen was a violation, I think.
Somebody will correct me if I am wrong, and perhaps tell when this change was made if I am right. In a nutshell, a moving screen is a blocking, or sometimes a holding foul by an offensive player attempting to make room for a teammate. You call this foul pretty much as you would on the defender restricting the movement of the opponent he/she is guarding.