Individual Action
Thomson Reuters v. ROSS
Thomson Reuters Enterprise Centre GmbH & West Publishing Corp. v. ROSS Intelligence Inc.
Where it stands
The Third Circuit heard oral argument on June 11, 2026 before Judges Restrepo, Montgomery-Reeves and Bove on the certified questions of headnote originality and fair use, with an opinion expected in late 2026.
Key ruling
Feb. 11, 2025 — Judge Stephanos Bibas reversed his own prior ruling and granted Thomson Reuters summary judgment, holding that ROSS's use of Westlaw headnotes to build a competing research tool was not fair use — the first US merits decision rejecting fair use for AI training.
The record
- Court
- D. Del.
- Case number
- 1:20-cv-00613 (SB)
- Filed
- 2020-05-06
- Defendants
- ROSS Intelligence Inc.
- Plaintiffs
- Thomson Reuters and West Publishing, owners of Westlaw headnotes and the Key Number System — corporate plaintiffs, not a class
- Technology at issue
- ROSS Intelligence legal research AI
- Relief sought
- Damages for copying Westlaw headnotes into ROSS's training data and injunctive relief
Claims pleaded
Sources (3)
- Third Circuit Hears Oral Argument in Ross v. Reuters AI Training Copyright CaseBaker Botts LLP · 2026-07-01
- At 3rd Circuit, Judges Press ROSS and Thomson Reuters on Fair Use, AI Training and Market HarmLawSites (LawNext) · 2026-06-12
- Status of all 39 copyright lawsuits v. AI (Feb. 18, 2025): Judge Bibas rejects fair use in AI trainingChat GPT Is Eating the World · 2025-02-19
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