[trumpdong]

functional parts not being copyrightable means that you can't claim a program is a copyright violation based on the fact it does the exact same thing based on compatibility reasons (you can copy what the program does). E.g. git stores refs in .git/refs, so does grit, that's not a violation. You still can't copy the program.

[gpm]

Yes... and now we get to the fact specific question of "did they copy the program". Or actually the answer to that is plainly "no" - they made something similar from it - and didn't run ctrl-c ctrl-v in an unlicensed manner, but "did they copy the relevant facets of the program into the new similar thing".

[trumpdong]

Making something similar is copying for the purpose of copyright law. If I trace over a Disney character it's still copyright Disney.

[gpm]

No. You're allowed to make a similar tool, the functional elements are not copyrightable. There's a long history, predating LLMs by many decades, of doing this in the software industry.

My use of the word "similar" does not imply here that I think it's obvious that they are "similar" in any copyrightable elements - whether they are or not is one of the interesting questions I think this case would have to resolve.

Incidentally you're also allowed to make similar creative elements so long as they aren't copies and you did so independently... which could actually come up in a case like this (imagine the LLM produced a similar function to some function in the original... but the original wasn't in the context window at the time. Not at all unlikely with code where there often is only one or two natural ways to write something).