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Preservation and lost films

The vast majority of the silent films produced in the late 19th and early 20th centuries are considered lost. According to a September 2013 report published by the United States Library of Congress, some 70 percent of American silent feature films fall into this category. There are numerous reasons for this number being so high. Some films have been lost unintentionally, but most silent films were destroyed on purpose. Between the end of the silent era and the rise of home video, film studios would often discard large numbers of silent films out of a desire to free up storage in their archives, assuming that they had lost the cultural relevance and economic value to justify the amount of space they occupied. Additionally, due to the fragile nature of the nitrate film stock which was used to shoot and distribute silent films, many motion pictures have irretrievably deteriorated or have been lost in accidents, including fires (because nitrate is highly flammable and can spontaneously combust when stored improperly). Examples of such incidents include the 1965 MGM vault fire and the 1937 Fox vault fire, both of which caused catastrophic losses of films. Many such films not completely destroyed survive only partially, or in badly damaged prints. Some lost films, such as London After Midnight (1927), lost in the MGM fire, have been the subject of considerable interest by film collectors and historians.

Major silent films presumed lost include:

Though most lost silent films will never be recovered, some have been discovered in film archives or private collections. Discovered and preserved versions may be editions made for the home rental market of the 1920s and 1930s that are discovered in estate sales, etc. The degradation of old film stock can be slowed through proper archiving, and films can be transferred to safety film stock or to digital media for preservation. The preservation of silent films has been a high priority for historians and archivists.