AFAIK, there have been several legislation changes (often at the behest of Disney) to extend copyright protection length. It was often done retroactively throug

AFAIK, there have been several legislation changes (often at the behest of Disney) to extend copyright protection length. It was often done retroactively through several years of content. So many years of material were extended through this specific year instead of works expiring for a particular limit for work (e.g. 75 years).