Title rumour

Oren Aviv the President of Production for Walt Disney Pictures mentioned on August 7, 2006 at his "Disney's Behind the Scenes: 'Pirates of the Caribbean: A Peek Inside the Chest'" presentation aboard the Disney Magic cruise ship that the premier of Jack Sparrow in the third movie will have Sparrow inside what Aviv called "Davy Jones's locker". At the same presentation when asked about the name of the third film, Aviv said that the company had not yet decided between World's End and At World's End."

source: Wikipedia
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