Copyright is not like a patent where once it expires anyone can use the novel work.
Something else, while someone could repackage the earliest Mickey Mouse shorts once the copyrights expire, it is unlikely that someone could make new Mickey Mouse related stories, because of trademark and other issues - beyond that, 1923 mickey and 2017 mickey only have a passing resemblance.
http://createwebquest.com/sites/default/files/images/mickeym...
What we identify (as in most consumers of mickey related cartoons) identify as mickey mouse - didn't exist until fantasia in 1940. So long as WDC continues to make artwork with that character in it, and continues to keep up the trademark - the character itself will never leave copyright or trademark.
They don't.
The protections overlap yes, but are not the same thing.
At a minimum what we visually identify as mickey mouse wont leave copyright until, 2035 - but even then certain fundamentals of the character were not finalized until much later.
Copyright is not indefinite due to the series' continuation.
In the case of Mickey Mouse, this is a substantial part of the characters personality - most of which didnt come out until the successful shorts of the mid-30's.
The expiration of copyright on steamboat Willie, will not allow for anything but royalty free copying of that work.
https://fairuse.stanford.edu/case/klinger-v-conan-doyle-esta... leads me to believe that derivatives of Mickey Mouse that only draw from the public domain work should be fair use. So, no mentioning Minnie, and no stenciling off of a recent design.
The words "copyright" and "trademark" are different, and mean different things. You might know this and be fuzzing them for the sake of simplification, but if so, you've over-simplified. They are different, and treating them as the same is wrong and leads to confusion.
The copyright on Steamboat Willie will expire, allowing royalty-free use and copying of that movie, including Mickey Mouse. At that point, that version of Mickey Mouse will be free to us--BUT the ongoing trademark on the character will mean people should still stay away.
http://www.rightsofwriters.com/2011/04/copyright-in-fictiona...
But I'd be interested in better understanding WHY it applies, and a more legalistic description of what copyright actually mean in this context.
By the time the movie enters the Public Domain, Disney will be able to defend the clip with a trademark defense.
I could absolutely see Disney saying "That clip of Steamboat Willie is a trademark of Disney Animation Studios. If you use that in animation, you're diluting our trademark."
My understanding is merchandising fees are also an issue. Pooh alone apparently nets order $10B/year.
Similar situation, and a fantastic explanation how trademarks and copyright work and what they enable or limit in this regard.