Lost film

A lost film is a feature or short film that is no longer known to exist in any studio archives, private collections, or public archives, such as the U.S. Library of Congress.

During most of the 20th century, U.S. copyright law required at least one copy of every American film to be deposited at the Library of Congress, at the time of copyright registration, but the Librarian of Congress was not required to retain those copies: "Under the provisions of the act of March 4, 1909, authority is granted for the return to the claimant of copyright of such copyright deposits as are not required by the Library." Of American silent films, far more have been lost than have survived, and of American sound films made from 1927 to 1950, perhaps half have been lost.

The phrase "lost film" can also be used in a literal sense for instances where footage of deleted scenes, unedited, and alternative versions of feature films are known to have been created but can no longer be accounted for. Sometimes a copy of a lost film is rediscovered. A film that has not been recovered in its entirety is called a partially lost film. For example, the 1922 film Sherlock Holmes was eventually discovered but some of the footage is still missing.

Most film studios routinely had a still photographer with a large-format camera working on the set during production, taking pictures for potential later publicity use. The high-quality photographic paper prints that resulted – some produced in quantity for display use by theaters, others in smaller numbers for distribution to newspapers and magazines – have preserved imagery from many otherwise lost films. In some cases, such as London After Midnight, the surviving coverage is so extensive that an entire lost film can be reconstructed scene by scene in the form of still photographs. Stills have been used to stand in for missing footage when making new preservation prints of partially lost films.

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