Rights holders often do not enforce copyright on promotional material. You can frequently find the or TV spots archived in the "Movies" section.
This is where the search for Kung Fu Panda 3 gets complicated.
The Internet Archive (archive.org) is a non-profit digital library offering millions of free books, movies, software, and music. Its primary mission is "universal access to all knowledge." While it is a goldmine for public domain films, historical archives, and out-of-print media, it also hosts user-uploaded content. Finding Kung Fu Panda 3 on the Archive
