is there any case filed against it?
Yes, Pixar was sued by Lori Madrid.
Monsters, Inc.
hortly before the film's release, Pixar was sued by children's songwriter Lori Madrid of Wyoming, stating that the company had stolen her ideas from her 1997 poem "There's a Boy in My Closet".

who does the voice of sully in monsters inc John Goodman. is it a film or tv series? Film. genre? Computer-animated comedy film. who is the creator of it? Pete Docter. name the main character? James P. "Sulley" Sullivan and Mike Wazowski. who is this person in the film? UNANSWERABLE who played these characters? John Goodman and Billy Crystal.
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Monsters, Inc. [SEP] Lawsuits
Her lawyer asked the court to issue a preliminary injunction, that would forbid Pixar and Disney from releasing the film while the suit was pending. In a hearing on November 1, 2001 – the day before the film's scheduled release on 5,800 screens in 3,200 theaters across the country – the judge refused to issue the injunction. On June 26, 2002, he ruled that the film had nothing in common with the poem.