Marking Your Ball on the Green

Question
I was told that you can't mark your ball on the green if a playing partner is still off the green unless you playing partner allows it.  Is this true, are there any exceptions to this and what is the penalty for marking without approval?  Thanks for your help, Lewis

Answer
Dear Lewis, thanks for the question.  There is no penalty for marking your ball.  It is yours to do with whatever you like, and whenever you like...on the green of course.  A playing partner can indeed ASK you to leave it in the event that it either helps him visually or he intends to use it as a backboard.  Either way, it is a request, not a command.  Only you can decide regarding your own ball.  Good luck, thanks for the question and remember...

Love the game,
skipper