The Supreme Court Just Made It a Lot Harder to Sue the Internet for Copyright Infringement
Cox Communications, Inc. v. Sony Music Entertainment, 607 U.S. ___ (2026), decided March 25, 2026, is the most consequential secondary copyright liability decision since MGM Studios v. Grokster in 2005. The Supreme Court threw out a $1 billion jury verdict against Cox Communications, eliminated a fifty-year-old liability theory, and told rights holders something they did not want to hear: knowing about piracy and doing nothing is not enough to make an internet service provider legally responsible for it.
That is a big deal. And it reaches well beyond music.
How a Billion Dollars Disappeared
The facts were not flattering for Cox. Sony and other major record labels sent Cox over 163,000 infringement notices identifying specific IP addresses engaged in BitTorrent piracy. Cox terminated 32 subscribers for infringement during that period. It disconnected more than 600,000 for nonpayment. An internal Cox email from its abuse team read, simply: "F the DMCA!!!"
A jury in the Eastern District of Virginia awarded the labels $1,000,278,736 in statutory damage, roughly $99,830 per work across 10,017 copyrighted songs, finding Cox willfully liable for both contributory and vicarious infringement.
The Fourth Circuit reversed vicarious liability (Cox's flat-rate subscription fees provided no direct financial benefit from the piracy itself), but affirmed contributory liability. The $1 billion verdict was vacated and remanded for a new damages trial on contributory infringement alone.
Then the Supreme Court took the case, and the billion dollars disappeared entirely.
Intent Is Now the Whole Game
Writing for seven justices, Justice Thomas established a two-track test for contributory copyright infringement. A service provider is liable only if it intended its service to be used for infringement — and intent is provable in exactly two ways:
Inducement. The provider affirmatively encouraged infringement through express promotion or marketing of the service for that purpose. This tracks Grokster directly.
Tailoring. The service lacks substantial or commercially significant noninfringing uses — meaning it was effectively designed for infringement. This is the inverse of the Betamax safe harbor, applied offensively.
Cox satisfied neither. The Court found that Cox repeatedly discouraged infringement by sending warnings, suspending accounts, and terminating subscribers. Internet access obviously has massive lawful uses. The majority was blunt: "Mere knowledge that a service will be used to infringe is insufficient to establish the required intent to infringe."
That sentence just buried decades of secondary liability doctrine.
What the Court Actually Killed
For over fifty years, courts applied a three-part framework for contributory liability: inducement (Grokster), the inverse of the Betamax safe harbor, and — most commonly — "knowledge plus material contribution," drawn from the Second Circuit's 1971 Gershwin decision and extended by the Ninth Circuit in A&M Records v. Napster (2001).
The Napster theory was simple and powerful: if you knew infringement was happening and you materially contributed to it by providing the platform or service, you were liable. Courts applied it aggressively. The music industry built an entire enforcement strategy around it.
The Supreme Court just eliminated it as an independent basis for liability.
Cox holds that Sony Corp. v. Universal City Studios (Betamax, 1984) and Grokster (2005) represent the beginning and the end of contributory infringement doctrine. The knowledge-plus-material-contribution theory that the Ninth Circuit applied in Napster — and that the Fourth Circuit applied against Cox — no longer works as a standalone theory. You need intent. Full stop.
Justice Sotomayor, joined by Justice Jackson, concurred only in the judgment. She agreed Cox should win, but accused the majority of needlessly foreclosing other theories and would have applied a broader aiding-and-abetting framework drawn from Twitter, Inc. v. Taamneh (2023). Her concurrence leaves the door open a crack — but the majority slammed it.
The Collateral Damage Is Significant
The Fifth Circuit's 2024 decision in UMG Recordings v. Grande Communications, upholding a $47 million verdict against another ISP on nearly identical facts, applied the same knowledge-plus-material-contribution theory the Supreme Court just rejected. That verdict is almost certainly invalid under the new standard.
The DMCA's repeat-infringer policy requirement under 17 U.S.C. § 512(i) is also in a strange place now. If an ISP faces no underlying contributory liability even without DMCA safe harbor protection, the incentive to maintain a meaningful repeat-infringer policy is substantially reduced. The RIAA's Mitch Glazier acknowledged this immediately, calling on policymakers to examine the ruling's impact. Legislative pressure is coming.
Why This Matters for AI and the Next Wave of Infringement Cases
The timing of Cox is not coincidental. The same week the Court issued the opinion, dozens of AI copyright infringement cases were pending in various federal courts, with plaintiffs attempting to hold AI companies secondarily liable for training on copyrighted works and generating infringing outputs.
Cox does not resolve those cases, but it frames them. A general-purpose AI tool — one that can write, analyze, code, and create — looks a lot like a general-purpose ISP under the majority's framework. It has substantial noninfringing uses. If the company did not specifically design or market the model for infringement, the tailoring and inducement tests are difficult to satisfy.
Rights holders will push back that AI training is categorically different — that the infringement is embedded in the product, not committed by third-party users. That argument has real force and distinguishes the AI cases from Cox in important ways. But any plaintiff in an AI secondary liability case will now have to contend with the intent requirement the Court has imposed.
The Bottom Line
Cox Communications v. Sony Music Entertainment narrows the scope of copyright enforcement against intermediaries more than any decision in two decades. By requiring proof of intent — and limiting intent to inducement or deliberate tailoring for infringement — the Court has insulated general-purpose platforms, ISPs, and infrastructure providers from secondary liability even when they know their services are being used for infringement and do relatively little about it.
Rights holders are not without recourse. Direct infringers, platforms built for piracy, and providers who actively market themselves to infringers remain exposed. Criminal enforcement, domain seizures, and targeted civil litigation against actual pirates are unaffected.
But the strategy of leveraging ISPs and general platforms as pressure points in copyright enforcement — using the threat of secondary liability to compel aggressive policing of subscriber conduct — has been significantly curtailed. The Court has decided that intent matters, and that knowledge alone, however detailed or deliberately ignored, is not intent.
For anyone working the intersection of copyright, signal piracy, and platform liability, this decision is required reading. And for anyone wondering whether Congress will respond — watch closely. When a unanimous Supreme Court hands the content industry a $1 billion loss and Justice Sotomayor calls the result a dismantling of the incentive structure Congress created, legislators tend to pay attention.
Jonathan Phillips is a founding partner at Phillips & Bathke, P.C. in Peoria, Illinois, where he practices intellectual property litigation, copyright enforcement, internet law, and related matters.