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The villain Charles Muntz has a similar name to Charles Mintz, the Universal Pictures executive who in 1928 stole Walt Disney's production rights to his highly-successful "Oswald the Lucky Rabbit" cartoon series. This led Walt Disney to create Mickey Mouse, who soon eclipsed Oswald in popularity.

The age time-lines of the characters don't add up. When we see Carl as a child, Charles Muntz is a late middle aged man. But when they meet, they are about the same age. This is because the plot was slightly different in an earlier version of the movie. In that version, the birds' eggs would keep you alive for ever if you ate them, which is why Muntz was so interested in the bird, and the reason why he is still alive when Carl meets him. Pixar eventually decided to drop the concept about the eggs, but by then it was too late to change the part about Muntz still being alive and healthy. So they kept him in the final version and deliberately ignored that he should actually have been decades older than Carl.

The photographs of characters shown during the end credits thematically match the crew members' positions, as do the "Wilderness Explorer" badges that also appear.

In international prints, the label on the savings jar for Paradise Falls bears a drawing of said place as opposed to text.

Edited into Dug's Special Mission (2009)