So Little Fuzzy by H. Beam Piper is PD now? When did it enter PD?

By clutter48

I think it only got into the public domain in the US in 1991, since stuff from 1963 or earlier basically only got 28 years of protection (rounded up) unless the copyright got renewed. And for 1964 to 1977 the renewal was automatic, so Piper’s *Lord Kalvan of Otherwhen* doesn’t seem to be public domain here since it came out in 1964/5. That said, a lot of Piper probably is public domain, and Gutenberg seems to have listings for it: https://www.gutenberg.org/ebooks/author/8301