As an example, the entirety of the Disney Catalogue makes multiple references, or retellings of old Folk Tales from Europe, while also defending their "Intellectual Property" so fiercely, that they artificially extended copyright from 56 years to 96 years for corporately owned products, or the author's life and 70 years for a single author.

It used to be roughly on par with Patent expiration, but it's now almost either 100 years to almost 200.