Key (basketball)

Due to the narrow key, imposing centers, such as George Mikan, dominated the paint, scoring at will.

On April 25, 2008, the FIBA Central Board approved rule changes that included the shape of the key.

In addition, the no-charge semicircle formally called the restricted area arc was also created.

In addition to the bounding rectangle, the key includes a free-throw circle at its head or top.

[6] Beginning after the 2010 FIBA World Championship, all FIBA-administered tournaments use a rectangular key 4.9 meters (16 ft) wide.

In the NBA and Euroleague Basketball competitions, the boundary of the half closer to the basket is traced in a broken line in order to space players properly for jump balls.

[5][6] The lane is a restricted area in which players on offense (in possession of the ball) can stay for only three seconds.

At all levels of play, after three seconds the player is assessed a three-second violation which results in a turnover.

[3] In FIBA-sanctioned tournaments, defending team players are allowed to stay in the key with no time limit.

Otherwise if a defender exceeds that time, the defending team is charged with a defensive three-second violation, which results in a technical foul where the team with the ball is awarded one free throw, plus retaining possession and a reset of the shot clock.

In FIBA play, that only applies if the shooter misses, since a successful attempt negates all other penalties.

If the drive starts inside the Lower Defensive Box (LDB – the area from the bottom tip of the free throw circle to the end line between the two 3‑foot posted-up marks), the secondary defender is allowed to be positioned inside the RA.

The NCAA approved adding a visible restricted-area arc three feet from the center of the basket in Division I men’s and women’s games for the 2011–2012 season.

[13] Starting with the 2015–2016 season, the NCAA moved the RA arc out to four feet from the center of the basket; the NAIA followed suit.

[14] The lane lines have marks separating where players stand during a free throw attempt.

Three different keys as used by different leagues in the world. The NBA one not rectangular, is wider than the one used by the NCAA and NAIA, and has a circle with the central diameter the edge of the key. The NCAA's or NAIA's key is virtually the same with the NBA's key but is narrower and has no hash marks for the lower half of the circle. FIBA's key is similar to the NBA's.
The different shapes of the key in different basketball disciplines (yellow, from left to right): NBA , NCAA , FIBA 1956–2010, and FIBA since 2010.
In this basketball game played in 1942, the key was much narrower than the free-throw circle.
Wally Szczerbiak shoots a free throw; in most leagues, the team of the free throw shooter has at most two players (aside from the free throw shooter) on the sides of the key, while the opposing team has three.
Jason Bohannon shoots a free throw; in the American NCAA and NAIA, there can be at most three players on each side of the key during a free throw.