The Ninth Circuit’s decision this week in Doe v. GitHub, Inc., No. 24-7700 (9th Cir. Sept. 16, 2026) marks a milestone in the biggest pending case about AI coding, and a potentially big win for defendants in AI training cases.
The GitHub Copilot class action was one of the earliest AI cases, at the head of a wave that now includes over 50 pending cases. It was filed November 3, 2022 in the Northern District of California against GitHub, Microsoft, and OpenAI. The initial complaint alleged violations of the Digital Millennium Copyright Act (DMCA), breach of GitHub’s terms of service, unfair competition, fraud, unjust enrichment, and other claims, seeking damages exceeding $9 billion. Notably, it was not a copyright infringement action, though many observers have treated it as a proxy for a copyright infringement action, and it was followed by a spate of copyright cases alleging similar facts about AI training.
As the case progressed, the court considered several amended complaints and motions to dismiss. The court finally dismissed the DMCA claim, but because the ruling presented, in Judge Tigar’s words, “substantial ground for difference of opinion,” he certified it for interlocutory appeal to the Ninth Circuit under 28 U.S.C. § 1292(b). This is an unusual step where a specific issue is appealed while the case is still ongoing in trial court.
No DMCA Claim
On the appeal, Plaintiffs argued two theories for how Copilot violates the DMCA, 17 U.S.C. § 1202(b). Under the “input” theory, they argued that GitHub stripped that information when it used licensed code for Copilot’s training data. Under the “output” theory, they argued Copilot strips that information each time it produces code resembling a training example without the attribution that accompanied the original.
The Ninth Circuit panel did not reach the input theory. It held plaintiffs forfeited the argument by failing to assert it clearly in the district court.
The Ninth Circuit opinion stated:
At the hearing on defendants’ first motion to dismiss, the court asked whether the act of copying training data into Copilot
violated the attribution requirement of open-source licenses, and plaintiffs’ counsel answered, “Perhaps it doesn’t.” The court then observed that the “complaint is not about training. It just isn’t.”
This is somewhat ironic because other AI training claims have had the most success on the input aspects of training (as in Bartz v. Anthropic, where the award of damages was based on using input from pirate sites). However, an “input” claim based on training might be a stretch, given open source licenses freely grant use of the software for any purpose. GitHub elected to train its AI on material available under open source licenses, presumably because this was clear the input step under a license defense. The notice and source code sharing conditions of open source licenses are triggered only by re-distribution of the licensed code, not by the internal use that training would probably represent.
As to the output claim, essentially the plaintiffs lost on the merits. The Ninth Circuit opinion held that Section 1202(b) requires the removal or alteration of the copyright management information (CMI) attached to an existing copy of a work. It stated:
The statutory definition of CMI reinforces this reading. CMI is “information conveyed in connection with copies . . . of a work,” not in connection with excerpts or derivative works. 17 U.S.C. § 1202(c) (emphasis added).
The court did not go so far as affirming a so-called identicality requirement.
The district court and defendants characterize this principle as the DMCA’s “identicality” requirement. But “identicality” is something of a misnomer because the DMCA does not require literal identicality between the plaintiff’s work and the allegedly infringing work. The concept of “identicality” is best understood as a gloss on the statutory terms “remove,” “alter,” and “copies” rather than
an independent (and atextual) element of a section 1202(b) claim.
The court cited New York Times Co. v. Microsoft Corp., 777 F. Supp. 3d 283 (S.D.N.Y. 2025), saying that “Minor cosmetic changes will not necessarily
protect a defendant who substantially or entirely reproduces
the protected work and removes CMI.” But it nevertheless held that the plaintiff in the case at hand had failed to state a claim.
DMCA Versus Fair Use
When this case was filed, many observers were surprised that it was not a copyright infringement claim. Reading between the lines, there are two problems with bringing class action AI lawsuits as copyright claims. First, copyright claims require a copyright registration, and few software authors register their copyrights. This would have made shepherding a plaintiff class into cohesion difficult. Second, plaintiffs’ lawyers had strong incentives to find a theory that bypassed the fair use defense of copyright. Many commentators believe that AI training is fair use, and in fact, the DOJ recently filed a statement of interest to this effect in another, significant pending AI training case.
Fair use may be not only a doctrinal weakness, but a practical one. It is an extremely costly defense to litigate (such as Oracle America, Inc. v. Google LLC, 141 S. Ct. 1183 (2021), in which the legal fees reportedly reached over $100 million over a 10-year period). That made Section 1202(b) a tempting alternative vehicle for a class action. While the DMCA is part of the US copyright law, it is not a copyright infringement claim to which the fair use defense would apply. Also, its statutory damages run up to $25,000 per violation under 17 U.S.C. § 1203(c)(3). $25,000 is not enough for a single plaintiff to litigate, but with a large plaintiff class, those damages would add up. Class action counsel is always looking for cases with high-value aggregated damages. Interestingly, the DMCA seems to be rarely used for the purpose for which it was enacted–essentially large scale piracy of works like CDs and DVDs with copy protection.
The Ninth Circuit rejected the DMCA claim, saying, “We decline plaintiffs’ invitation to transform run-of-the-mill copyright-infringement claims into DMCA claims.”
DMCA is Out, but Other Claims Stay
The court reserved judgment on whether Copilot’s output, where it resembles code in the training corpus, could support an ordinary copyright infringement claim–though no such claim is before the court in this case. Indeed, other cases alleging infringing nature of the output of AI have not fared well.
The claim that using the code was a violation of open source license terms (i.e. a claim of breach of contract) remains pending before the district court. So while this decision does not resolve whether AI training or AI output infringes the copyrights in the underlying code–and it says nothing about the fair use question that will likely decide that issue more broadly–it likely forecloses the DMCA end-run around copyright infringement claims. Not all courts in the US are bound to follow the Ninth Circuit, but this opinion will likely carry significant weight even in jurisdictions where it is not precedential.
However, this decision does not solve the spate of litigaiton about AI training, by any means. Software code is not the same as more conventional works of authorship such as books, movies, or audio. Copyright infringement in software is a harder case to make for a plaintiff, due to the functional nature of software, and the tendency of coding to mix and match snippets of code. This causes copyright claims to run headlong into defenses of merger and idea/expression dichotomy limitations. But plaintiffs in AI cases for other kinds of works might still be eyeing this decision with dismay.








