When golfers get on the green -- technically called the putting surface -- on any hole on a golf course, they typically put down a ball marker and pick up the golf ball.
Almost universally, golfers put their marker down behind the ball, then pick up the ball. But do the Rules of Golf mandate that a player has to place their ball marker behind the golf ball?
Where are golfers allowed to mark their ball on the green?
According to the Rules of Golf, players are not required to place their marker behind the golf ball when marking it on the green.
Golfers are only required to place their marker next to the golf ball. That means golfers are allowed to place their mark anywhere next to the ball, including in front of, behind and to the side of the ball. The only requirement is that it's directly adjacent to the ball's original position.
From there, a golfer may occasionally need to temporarily move their mark to accommodate another player whose line to the hole with their putt might come in contact or conflict with their marker. A player can then move that marker, measuring away from the original position using an object of measure and a reference point, like a tree. Once that potentially conflicting putt is hit, a player can then use that same object of measure and a reference point to return the marker to its original location before replacing it with their ball.
A player must replace their marker with the ball, using their hand and setting the ball down. They cannot use their putter head or another instrument to move the ball to the marked position, otherwise they are subject to a penalty.
A golfer is also required to pick up or otherwise move their ball marker from its position after the ball has been placed. If a golfer makes a stroke with the marker still positioned next to the ball, the player is penalized a stroke.