The secret directive preventing the Axiom from returning to Earth is code-named A113.
A113 is issued by Shelby Forthright, the CEO of Buy n Large, after the company’s evacuation plan fails. Humanity leaves Earth expecting the WALL-E cleanup robots to restore the planet within several years, but the environment remains too dangerous. Forthright consequently orders the Axiom and the other starliners to stay in space indefinitely.
The directive becomes the central obstacle in the film’s final act. Captain McCrea wants to follow the plant’s positive life-detection result and return home, but AUTO remains loyal to the old command. AUTO attempts to prevent the return by resisting the captain and tilting the Axiom during the struggle at the holo-detector.
A113 is also a famous recurring reference in animation, especially associated with an animation classroom at California Institute of the Arts. In WALL-E, however, it has a specific plot meaning: it is the Buy n Large directive that overrides the captain’s decision and traps humanity aboard the ship.