It is possible, that Pixar will create another sequel to "WALL-E", but if it will be, it will be after 2016, because there will be "Finding Dory" (sequel to "Finding Nemo") in 2015 and then, probably, Pixar will make "WALL-E 2".

For example, "WALL-E" movie is not fully told about the fate of other spacecrafts "Axiom". Other "Axioms" are guided by other AUTOs, which continue to obey the command "A113". This command was created by the BnL corporation in order to prevent the return of "Axioms" to the Earth. Will these spaceships go back home? It's unknown.     

Andrew Stanton, the creator of "WALL-E", said in his Twitter in February 2012, that the sequel to "Wall-E" and "Finding Nemo" can be created. In the summer of 2012 he decided to start working on "Finding Dory", maybe in future he will create "WALL-E 2" too.
we’ll never get to see what happens on building the Earth back. there is plenty of potential for this movie to succeed, and we believe that WALL-E deserves justice for a second film.Walt Disney was working on WALL-E 2 but it got dropped for other movies being made at that time. Keep the WALL- E memory alive for upcoming generations.

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