When a player is putting a ball into play from the teeing ground, it must be played from within the teeing ground and from the surface of the ground or from a conforming tee (see Appendix IV) in or on the surface of the ground.
For the purposes of this Rule, the surface of the ground includes an irregularity of surface (whether or not created by the player) and sand or other natural substance (whether or not placed by the player).
If a player makes a stroke at a ball on a non-conforming tee, or at a ball teed in a manner not permitted by this Rule, he is disqualified.
A player may stand outside the teeing ground to play a ball within it.
Before a player makes his first stroke with any ball on the teeing ground of the hole being played, the tee-markers are deemed to be fixed. In these circumstances, if the player moves or allows to be moved a tee-marker for the purpose of avoiding interference with his stance, the area of his intended swing or his line of play, he incurs the penalty for a breach of Rule 13-2.
11-3. Ball Falling off Tee
If a ball, when not in play, falls off a tee or is knocked off a tee by the player in addressing it, it may be re-teed, without penalty. However, if a stroke is made at the ball in these circumstances, whether the ball is moving or not, the stroke counts, but there is no penalty.
11-4. Playing from Outside Teeing Ground
a. Match Play
If a player, when starting a hole, plays a ball from outside the teeing ground, there is no penalty, but the opponent may immediately require the player to cancel the stroke and play a ball from within the teeing ground.
b. Stroke Play
If a competitor, when starting a hole, plays a ball from outside the teeing ground, he incurs a penalty of two strokes and must then play a ball from within the teeing ground.
If the competitor makes a stroke from the next teeing ground without first correcting his mistake or, in the case of the last hole of the round, leaves the putting green without first declaring his intention to correct his mistake, he is disqualified.
The stroke from outside the teeing ground and any subsequent strokes by the competitor on the hole prior to his correction of the mistake do not count in his score.
11-5. Playing from Wrong Teeing Ground
The provisions of Rule 11-4 apply.
©USGA, used with permission