Lawsuit tracker
Authors Guild v. OpenAI
Authors Guild v. OpenAI Inc., No. 23-cv-08292 (S.D.N.Y.), consolidated in In re OpenAI, Inc. Copyright Infringement Litigation, MDL No. 3143
| Plaintiffs | The Authors Guild and seventeen named authors, including John Grisham, George R.R. Martin, Jodi Picoult and Jonathan Franzen, on behalf of a proposed class |
|---|---|
| Defendants | OpenAI entities and Microsoft Corporation |
| Court | U.S. District Court for the Southern District of New York (Judge Sidney H. Stein) |
| Filed | 2023-09-19 |
| Status | Active |
| Content type | Books — fiction and nonfiction, including works allegedly obtained from shadow-library datasets |
| Last updated | 2026-07-21 |
The claims
Direct, vicarious and contributory copyright infringement over the copying of books to train GPT models and over allegedly infringing ChatGPT outputs
What has happened
The Authors Guild and seventeen prominent novelists sued OpenAI in September 2023, alleging their books were copied without permission to train GPT models; an amended complaint added Microsoft that December. In April 2025, the Judicial Panel on Multidistrict Litigation centralized a dozen OpenAI copyright cases — including the earlier Tremblay and Silverman author suits from California and the New York Times case — before Judge Sidney Stein in Manhattan. The author plaintiffs filed a consolidated class action complaint in June 2025. In October 2025, Stein denied OpenAI’s motion to dismiss the output-based direct infringement claim, finding ChatGPT outputs could be substantially similar to the books. Discovery then produced a fight over OpenAI’s 2022 deletion of two LibGen-derived training datasets, with a magistrate judge ordering OpenAI in late 2025 to hand over internal Slack messages about the deletions. Fact discovery closed on February 27, 2026, and the court has pushed summary judgment reply briefs to November 6, 2026.
Key developments
- 2023-09-19 — The Authors Guild and seventeen authors file a proposed class action in the Southern District of New York; Microsoft is added as a defendant that December.
- 2025-04-03 — The JPML centralizes the OpenAI copyright cases into MDL No. 3143 before Judge Sidney Stein, folding in the Tremblay and Silverman author suits.
- 2025-06-13 — Author plaintiffs file a consolidated class action complaint asserting direct, vicarious and contributory infringement against OpenAI and Microsoft.
- 2025-10-27 — Judge Stein denies OpenAI’s motion to dismiss the authors’ output-based direct infringement claim.
- 2026-02-27 — Fact discovery closes in the MDL, after rulings ordering OpenAI to produce records about its deleted books1 and books2 datasets.
- 2026-03-24 — The court extends summary judgment briefing; reply briefs are now due November 6, 2026.
Why it matters for training data
This is the largest consolidated author action against a model developer, and it is testing questions the settled cases skipped: whether outputs infringe, and what happens when training data disappears. OpenAI’s 2022 deletion of two book datasets became a discovery weapon, with courts ordering production of internal messages about the erasure — a willfulness and spoliation risk that reads as a records-retention mandate. For buyers and suppliers alike, dataset lineage documentation is now litigation infrastructure.
Sources
- CourtListener docket: In re OpenAI, Inc. Copyright Infringement Litigation (MDL 3143)
- Saul Ewing: class of authors can pursue infringement claims against OpenAI
- The Hollywood Reporter: OpenAI loses discovery battle over deleted pirated-book datasets
- Chat GPT Is Eating the World: summary judgment briefing pushed to November 2026
- Authors Guild: understanding the AI class action lawsuits
Deeper analysis
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