Mickey's version of the short "Steamboat Willie" went public domain in the U.S.A. today.

In my country, Brazil, Mickey Mouse will only enter the public domain in 2042, due to co-authorship and the death of the last co-author in 1971.
In Brazil, copyright protection lasts for 70 years, counting from the first day of the year following the author's death.
Therefore, this protection always falls on January 1st of each year.