One provision of the Sony Bono Copyright Extension Act [0] (which expired 6 months after passage of the law) allowed next-of-kin to revoke (the sale of) copyrights sold by the author without recourse (by the folks who paid for them). Allegedly, this was added by Disney in order to cut costs hundreds of millions of dollars in a dispute over licensing Winnie The Pooh IP/rights [1].

Expect something similar when the next big author dies; my prediction: JK Rowling.

Notes:

0 - https://www.congress.gov/bill/105th-congress/senate-bill/505

1- https://hughstephensblog.net/2023/12/18/winnie-the-poohs-cop...