On February 11, 2025, the U.S. District Court for Delaware issued a landmark ruling in Thomson Reuters v. Ross Intelligence, marking the first significant federal decision on AI and copyright. Presided over by Judge Stephanos Bibas, the court found that Ross Intelligence infringed on Thomson Reuters' copyrights by using Westlaw's headnotes to train its AI legal research tool. The ruling dismissed Ross' fair use defense, determining that the use was not transformative as it directly replicated Westlaw's legal research service. The decision emphasized that this ruling does not apply to generative AI systems, which create new content, but rather to non-generative AI systems like Ross’. The court evaluated fair use based on four factors, ultimately ruling in favor of Thomson Reuters. This case has sparked widespread debate, with implications for over 39 ongoing AI-related copyright cases in the U.S. Meanwhile, the U.S. Copyright Office has clarified that purely AI-generated works cannot be copyrighted, but AI-assisted works may qualify if they include sufficient human creative input. The judgment underscores the challenges of balancing copyright law with emerging AI technologies, with critics arguing that the ruling could hinder innovation.