The dinosaur miniatures were donated to the Museum of Arts and Sciences in Los Angeles. After many years the rubber models began to sulphurize and disintegrate. They were stored away and inadvertently sealed between the walls of the facility when a new wing was added.
While filming one of the stop-motion scenes, the cameraman spotted a pair of pliers in the picture. So as not to draw attention to them by having them suddenly disappear, he moved them a little at a time until they were out of the shot.
In July 1929, the Kodascope Libraries acquired the 16mm rights to this film. The original lavender protection positive itself was edited down to five reels to create the abridged 16mm Kodascope version. This abridged Kodascope version was the only one widely known to survive in the U.S. until a more extensive (but still incomplete) original tinted, toned and hand-colored 35mm print was found in 2003 in the hands of a private collector and purchased by Film Preservation Associates.
When the explorers return to London, there is a shot of the London Pavilion with a flashing sign advertising a showing of The Sea Hawk (1924), a movie in which two of the film's stars, Wallace Beery and Lloyd Hughes, had also appeared.
This film was such a success that there were plans to do a sound remake. In possible preparation for this, Aileen Rothacker reached an agreement with First National to withdraw the film from distribution. First National was to destroy all release prints and the foreign negative but the domestic negative was to be retained. It is not known if the original negatives decomposed or if they were mistakenly disposed of.
The failure of the original copyright holder to renew the film's copyright resulted in it falling into public domain, meaning that virtually anyone could duplicate and sell a VHS/DVD copy of the film. Therefore, many of the versions of this film available on the market are either severely (and usually badly) edited and/or of extremely poor quality, having been duped from second- or third-generation (or more) copies of the film.
The strange, spiky Triceratops-like dinosaur was based on Charles R. Knight's famous painting of Agathaumas. Nowadays, scientists argue that such a dinosaur even existed. The painting itself was based on very fragmentary fossil remains, thus many features of the animal were purely speculative guesses.
The movie was rather forward-thinking with its depiction of dinosaurs as active land-dwellers. Many scientists at the time thought of dinosaurs as sluggish, and plant-eating dinosaurs were incorrectly thought to have lived in swamps and lakes to support their mass. Here, on the other hand, dinosaurs such as Brontosaurus are correctly shown stomping about on dry land and behaving very actively.