It is a question of circumstances whether a ball hit towards an obstruction that is not found is actually in the obstruction. In order to apply this rule, it must be known or virtually certain that the ball is in the obstacle. If this knowledge or certainty is lacking, the player must proceed in accordance with Law 27-1.
a) Ball not found in a moving obstacle
If it is known or virtually certain that a ball that has not been found is in a movable obstacle, the player may use another ball and claim relief without penalty under this rule. If he wishes to do so, he must remove the obstruction and drop a ball as close as possible to the spot immediately below the point where the ball last crossed the outermost boundary of the movable obstruction - but not closer to the hole - in the terrain or obstruction or lay it down on the green.
b) Ball not found in immovable obstruction
If it is known or virtually certain that a ball that has not been found is in an immovable obstruction, the player may claim relief under this rule. If he wishes to do so, the place where the golf ball last crossed the outermost boundary of the hazard must be identified and, for the purposes of applying this rule, the ball is deemed to be in that place. The player must then proceed as follows:
(I) In the field: If the ball has last crossed the outermost boundary of the immovable obstruction at any point in the ground, the player may, without penalty, use another ball and take the relief prescribed in Rule 24-2b (I).
(II) In a bunker: If the ball has last crossed the outermost boundary of the immovable obstruction at a point in a bunker, the player may use another ball without penalty and claim the relief prescribed in Rule 24-2b (II).
(III) In a water hazard (including a side water hazard): If the ball has last crossed the outermost boundary of the immovable obstruction at any point in a water hazard, the player may not claim relief without penalty and must proceed in accordance with Rule 26-1.
(IV) On the green: If the ball has last crossed the outermost boundary of the immovable obstruction at a point on the green, the player may use another ball without penalty and take the relief prescribed in Rule 24-2b (III).
PENALTY FOR BREACH OF RULES:
Hole play - Hole loss; Counting play - Two strokes.
Status: 2018