Answer: It’s a Wonderful Life

Released in 1946, It’s a Wonderful Life wasn’t exactly a box office fire starter. While far from a complete failure, the reaction to the film was lukewarm and it didn’t even recoup the production costs during its initial theatrical run. Today, however, the film is one of the most critically acclaimed films of all time and it enjoys both high praise from high brow film critics and adoration from fans in love with the wholesome holiday theme.

So what changed between the lukewarm audiences of 1946 and today? A minor copyright filing error that had a major effect on the public consumption of the film. The issue was that the copyright of the film was governed by the 1909 Copyright Act, which covers all creative works created before 1964 when further revisions to copyright laws in the U.S. were enacted. Specifically, the terms of copyright under the act allowed for one 28 year period and one renewal period of an additional 28 years. When the copyright for It’s a Wonderful Life came up for renewal in 1974, a clerical mistake led to the failure of renewal and the movie entered the public domain.

Television stations jumped on the opportunity to run a public domain Christmas film around the holidays and the movie went into heavy rotation on many different channels every holiday season. This pattern continued, year after year, until nearly 20 years later when a legal battle over the underlying story (which did not have a lapsed copyright) allowed the then current holder of the intellectual property surrounding the film to take control of it—bringing the run of wall-to-wall It’s a Wonderful Life free airings to a close.

At that point, though, the film was cemented in the minds of millions of Americans as a classic traditional holiday film and it still enjoys regular rotation (albeit with compensation to the copyright holders) every holiday season.