Debian debates AI models and the DFSG

Ideas are categorically exempt from copyright protection in the US (and most of the world). See for example 17 USC 102(b), and see also case law such as Baker v. Selden.

> What's to stop a plaintiff claiming you stole their "specific expression" (given that there are not *too* many "specific expressions" if you're talking small fragments) when they're unaware of where they got it from.

The "specific expression" refers to the actual words, images, or sounds used to convey something, not the broader concept of it. If you can show that the plaintiff copied the specific expression from elsewhere, then under US law, this has two rather significant consequences (both laid out in 17 USC 103):

1. They don't own that specific expression, because it's not part of "the material contributed by the author of such work."
2. If the copying was unlawful (the original was copyrighted and they had no license), then that entire part of the work is unprotected by copyright.

You cannot demand that the plaintiff give you an accounting of every place where it possibly could have come from and exhaustively prove that it is entirely original, because that would be plainly unworkable. Instead, you as the defendant have to find the original work (possibly through discovery), introduce it at trial, and argue that it precludes the plaintiff from owning the specific expression.

You can argue that the copied expression is a "scène à faire," literally meaning "a scene that must be done." The original basis for this was genre fiction, in which (for example) a mystery novel simply must have a scene at the end where the detective (who also must exist) explains who commited the crime, how and why they did it, and what clues led the detective to that conclusion. If you don't have that scene, it's not a "real" mystery novel, it's some other genre, and since nobody can be allowed to own the mystery genre as a whole, nobody can own that type of scene either.

In the programming context, scènes à faire includes constructs like for(i = 0; i < max; i++){...}. Nobody can be allowed to own that, because you can't reasonably write a (large, complex) program in a C-like language and never write a loop that looks like that.

> I gather there's been a "situation" recently where YouTube has misattributed Schubert's "the trout" (even worse, as played by a washing machine), and accused a whole bunch of people of copyright violations, taken a large chunk of their commissions, and given it to somebody who has no connection with Schubert or the trout.

Disclaimer: I work for Google, not as a copyright lawyer, and so I can't speak on their behalf. The following is my personal interpretation of YouTube's behavior, based on public information and reasonable inference.

YouTube's copyright system is primarily designed to protect YouTube from getting sued, and secondarily designed to discourage users from suing each other. You cannot assume that the outcomes you see on YouTube are necessarily what a court of law would have done, because YouTube does not have the power to make binding rulings on whether X is a copyright infringement of Y. So they're stuck making rulings on the basis of whether YouTube can plausibly be sued, which leads to all sorts of undesirable-but-unavoidable biases in favor of the copyright holder (many of them explicitly codified into law, e.g. in 17 USC 512 and similar laws in other jurisdictions). Of course, anyone dissatisfied with YouTube's handling of an issue remains free to take it to the "real" court system under a variety of legal theories (slander of title, tortious interference, conversion of revenues, 17 USC 512(f) misrepresentation, etc.).

I will agree that the legal system generally does a poor job of producing just and efficient outcomes in this space. There is a reason that both YouTube and its users strongly prefer to avoid going to court. But scènes à faire has nothing to do with this. What you describe sounds like outright fraud (taking the facts as you have described them and assuming there's nothing else going on here). Unfortunately, modern copyright law was simply not designed under the assumption that services like YouTube might exist, and updating it has proved difficult (especially in the modern US political system where Congress can barely agree to keep the government open). A few years ago, the YouTuber Tom Scott made an excellent ~43 minute video explaining the broader problem in detail, which I found highly informative and more entertaining than you might expect: https://www.youtube.com/watch?v=1Jwo5qc78QU