When does the shot clock start, and when is it reset to 24 seconds?

Start or restart the shot clock (Art. 51.1) when:

• a team gains control of a live ball on the court. After that, an opponent merely touching the ball does not start a new period if the same team keeps control; or
• on a throw-in, the ball touches or is legally touched by any player on the court.

Stop and reset to 24, with no display showing (Art. 29.2 and 51.3), when:

• the ball legally enters the basket;
• the ball touches the ring and is then controlled by the team that did not have it before;
• the other team is awarded a backcourt throw-in after a foul or violation by the team in control, including the ball going out-of-bounds;
• the same team keeps the ball with a backcourt throw-in after a foul or violation by the opponents (but not when the ball went out-of-bounds);
• a team gets a backcourt throw-in from a jump ball situation, when it did not have control before;
• the game was stopped for something not connected with the team in control, or with either team (unless resetting would put the opponents at a disadvantage), and the throw-in is in the backcourt;
• a team is awarded free throws.

A shot as the clock expires: for the shot to be legal, the ball must leave the hand before the signal and then touch the ring or go in. If the signal sounds in error while a team has the ball, the referees ignore it unless the team was put at a disadvantage, in which case the clock is corrected.