The National Film Registry (NFR) is part of the National Film Preservation Board (NFPB), a division of the Library of Congress.
We, the general public, are encouraged to nominate up to 50 titles for consideration to the Registry by August 15.
American films (sorry, Seven Samurai) inducted this year will have been released in 2012 or earlier and are also "culturally, historically or aesthetically significant."
From NFPB : "The Registry is intended to reflect American society and the rich tapestry of American cinema since its inception around 1890."
They want nominations of "the full-range of American film-making: not just Hollywood classics or other well-known works, but also silent era titles, documentaries, avant-garde, educational and industrial films, as well as films representing the vibrant unmatched diversity of American cultureā¦"
25 films are added to the NFR each year, announced in December.
Nominate your choices on the Film Preservation Board Website.