I did a bit of digging. It seems the neckbolt version of Frankenstein is ...
Source: https://www.trademarkandcopyrightlawblog.com/2018/10/frankenstein-and-copyright-5-things-you-should-know/
If that's true, then we have to wait 2 years to copy neckbolt-flathead, because ...
https://www.theguardian.com/film/2022/jul/03/mickey-mouse-disney-copyright-expiry
What does the word "anonymous" mean in that context, though?