These companies are buying from small book stores; surely these collector types would know if they lost any one-of-a-kinds? Or at least someone would be keeping track of extremely rare books disappearing (especially now since this matter has been public for weeks).

Regardless I feel like they gotta figure this out for optics reasons. “So and so books are lost forever to Anthropic’s servers” is much more outrageous than “Anthropic is destroying a bunch of books that have other copies” imo.