When the Copyright Act was first enacted in the United States, the copyright duration was only 14 years. Today Copyright duration can last over a century in some cases. Why such a drastic change? Some say it is all due to a cute little mouse named Mickey.

Copyright duration had some changes over the 125-years before Mickey Mouse. In the Copyright Act of 1790, the 14-year term was renewable for one additional 14-year term, if the author was alive at the end of the first 14 years. And it only applied to maps, charts, and books. Registration and use of a copyright notice were also required. If you didn’t meet those requirements, the work immediately entered into the public domain. By 1831 it was changed to 28 years with a 14-year renewal and in 1909, copyright duration became 28 years with a 28-year renewal. Very few works actually maintained those copyright durations as only a small percentage of people even bothered to register copyrights in the first place, and of those that did, only a tiny fraction renewed them.

Disney now has until 2023 to figure out how to extend that date once again.

Enter Steamboat Willy, the first Mickey Mouse cartoon and the first animated short by Walt Disney in 1928. Under the 1909 Copyright scheme, the Mickey Mouse character had copyright protection for 56 years (with the renewal), expiring in 1984. With the impending loss of copyright on it’s mascot, Disney is said to have begun serious lobbying push for changes to the Copyright Act.

In 1976, Congress authorized a major overhaul of the copyright system assuring Disney extended protection. Instead of the maximum of 56 years with extensions, individual authors were granted protection for their life plus an additional 50 years, (which was the norm in Europe). For works authored by corporations, the 1976 legislation also granted a retroactive extension for works published before the new system took effect. The maximum term for already-published works was lengthened from 56 years to 75 years pushing Mickey protection out to 2003. Anything published in 1922 or before was in the public domain. Anything after that may still be under copyright.

With only 5 years left on Mickey Mouse’s copyright term, Congress again changed the duration with the Sonny Bono Copyright Term Extension Act of 1998. This legislation lengthens copyrights for works created on or after January 1, 1978, to “life of the author plus 70 years,” and extends copyrights for corporate works to 95 years from the year of first publication, or 120 years from the year of creation, whichever expires first. That pushed Mickey’s copyright protection out to 2023.

The chart above illustrates the “Mickey Mouse Curve,” showing how copyright duration has changed close to each time Mickey Mouse is about to expire.

Not everybody has been happy about these changes due to our inability to use old work to create new artistic works. One author noted that we are “the first generation to deny our own culture to ourselves” since “no work created during your lifetime will, without conscious action by its creator, become available for you to build upon.”

Disney now has until 2023 to figure out how to extend that date once again. In 5 years or so, we can probably expect to see stories about proposed changes to copyright duration, once again. It is unlikely that a company as strong as Disney will sit by and allow Steamboat Willie to enter the Public Domain.