I read that as "here's a list of reasons why Anthropic isn't usurping the market for copies of these books" and not "destroying a book makes scanning it legal".

I read that as "here's a list of reasons why Anthropic isn't usurping the market for copies of these books" and not "destroying a book makes scanning it legal". Non-destructive book scanning wasn't going to come up in this case because it's a hypothetical[0]. Courts don't deal in hypotheticals, so they didn't rule on nondestructive scanning. Normally, that would mean that the question is still open; Alsup or any other judge would be free to draw the line later. But there is also other Ninth Circuit precedent that explicitly legalizes nondestructive format shifting. If I rip a CD to play it on my phone, I'm not obliged to destroy the CD, but I can't sell the CD until and unless I delete the MP3s. I don't see why books would be different. EDIT: Also, forgot to mention that Google Books was built with non-destructively scanned books and that was ruled legal too, albeit in the Second Circuit instead of the Ninth. [0] To be clear, it's a hypothetical because it would be prohibitively expensive at the rate of which AI companies want to ingest pre-AI tokens.