AI Litigation Roundup

AI litigation in the US has expanded far beyond copyright disputes. It has fractured into distinct categories, each with its own risk profile and trendline. And the target is shifting. The first wave of litigation targeted model developers. The current wave increasingly centers on deployers, the organizations using AI tools in business operations, workflows, hiring pipelines, and customer-facing applications. Below is a survey of the major categories and trendlines.

1. Copyright and Training Data

This remains the largest category by volume and dollar exposure, and 2025 and 2026 produced the first real doctrine. Two decisions frame the issues. In Thomson Reuters v. Ross Intelligence, No. 1:20-cv-00613 (D. Del.), the court rejected a fair use defense where a legal research startup trained on Westlaw headnotes to build a competing product, emphasizing market substitution. In Bartz v. Anthropic, No. 3:24-cv-05417 (N.D. Cal.), Judge Alsup held in June 2025 that training on lawfully