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Cox beats Sony

Supreme Court rejects Sony’s attempt to kick music pirates off the Internet

Sony’s 1984 Betamax win helps Cox beat Sony in important online piracy case.

Jon Brodkin | 115
Supreme Court Justice Samuel Alito and Clarence Thomas wear their traditional robes at a presidential inauguration ceremony.
Supreme Court Justice Samuel Alito (L) and Clarence Thomas (R) at the inauguration of President Trump on January 20, 2025 in Washington, DC. Credit: Getty Images | Chip Somodevilla
Supreme Court Justice Samuel Alito (L) and Clarence Thomas (R) at the inauguration of President Trump on January 20, 2025 in Washington, DC. Credit: Getty Images | Chip Somodevilla
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The Supreme Court today decided that Internet service providers cannot be held liable for their customers’ copyright infringement unless they take specific steps that cause users to violate copyrights. The court ruled unanimously in favor of Internet provider Cox Communications, though two justices did not agree with the majority’s reasoning.

The ruling effectively means that ISPs do not have to conduct mass terminations of Internet users accused of illegally downloading or uploading pirated files. If the court had ruled otherwise, ISPs could have been compelled to strictly police their networks for piracy in order to avoid billion-dollar court verdicts under the Digital Millennium Copyright Act (DMCA).

The long-running case is Cox Communications v. Sony Music Entertainment. Cox was hit with a $1 billion verdict for music piracy in 2019. Although the damages award was overturned in 2024, a federal appeals court still found that Cox was liable for willful contributory infringement.

The Supreme Court decided to take up Cox’s appeal of the finding and heard oral arguments in December 2025. In today’s ruling, the court rejected Sony’s claims and found that Cox is not liable for its users’ copyright infringement.

Justice Clarence Thomas delivered the opinion of the court. “Under our precedents, a company is not liable as a copyright infringer for merely providing a service to the general public with knowledge that it will be used by some to infringe copyrights. Accordingly, we reverse,” Thomas wrote.

Cox did not induce subscribers to pirate music

Thomas’ opinion was joined by Chief Justice John Roberts, Samuel Alito, Elena Kagan, Neil Gorsuch, Brett Kavanaugh, and Amy Coney Barrett. Justice Sonia Sotomayor filed a concurring opinion that was joined by Ketanji Brown Jackson. Sotomayor objected to the majority limiting liability to the degree it did, but agreed that Cox is not liable for infringement.

“The provider of a service is contributorily liable for the user’s infringement only if it intended that the provided service be used for infringement,” Thomas wrote. “The intent required for contributory liability can be shown only if the party induced the infringement or the provided service is tailored to that infringement.”

The court decided today that a service is tailored to infringement if it is not capable of “substantial” or “commercially significant” noninfringing uses. The court cited Sony’s 1984 victory in the Betamax case, in which justices found that the Betamax was capable of noninfringing uses and that Sony’s sale of it did not constitute contributory infringement. Sony’s win in 1984 thus contributed to its loss today.

The Supreme Court’s 2005 ruling in MGM Studios v. Grokster was also important. Recalling the Grokster ruling, Thomas said the court has held that a service provider may be found to induce infringement if it actively encourages it, such as by promoting and marketing software as a tool to infringe copyrights. By contrast, Cox’s actions as the provider of Internet service did not induce infringement, Thomas wrote:

Thus, Cox is not contributorily liable for the infringement of Sony’s copyrights. Cox provided Internet service to its subscribers, but it did not intend for that service to be used to commit copyright infringement. Holding Cox liable merely for failing to terminate Internet service to infringing accounts would expand secondary copyright liability beyond our precedents.

Cox neither induced its users’ infringement nor provided a service tailored to infringement. As for inducement, Cox did not “induce” or “encourage” its subscribers to infringe in any manner. Sony provided no “evidence of express promotion, marketing, and intent to promote” infringement. And, Cox repeatedly discouraged copyright infringement by sending warnings, suspending services, and terminating accounts. As for providing a service tailored to infringement, Cox’s Internet service was clearly “capable of ‘substantial’ or ‘commercially significant’ noninfringing uses.” Cox did not tailor its service to make copyright infringement easier. Cox simply provided Internet access, which is used for many purposes other than copyright infringement.

Cox: Ruling affirms ISPs are not copyright police

Cox hailed the ruling in a statement the company provided to Ars. “The Supreme Court’s unanimous opinion is a decisive victory for the broadband industry and for the American people who depend on reliable Internet service,” Cox said. “This opinion affirms that Internet service providers are not copyright police and should not be held liable for the actions of their customers—and after years of battling in the trial and appellate courts, we have definitively shut down the music industry’s aspirations of mass evictions from the Internet.”

The Recording Industry Association of America (RIAA) said it is “disappointed in the court’s decision vacating a jury’s determination that Cox Communications contributed to mass scale copyright infringement, based on overwhelming evidence that the company knowingly facilitated theft. To be effective, copyright law must protect creators and markets from harmful infringement and policymakers should look closely at the impact of this ruling.” The RIAA argued that the ruling “is narrow, applying only to ‘contributory infringement’ cases involving defendants like Cox that do not themselves copy, host, distribute, or publish infringing material or control or induce such activity.”

We contacted Sony about its court loss and will update this article if it provides a response.

Cox’s arguments were supported by digital rights groups. “Today’s decision laid to rest the idea that private actors—and not just any private actors, but record labels—can determine when customers deserve to be excluded from applying to jobs, paying bills, and getting an education,” Meredith Rose, senior policy counsel at Public Knowledge, said. “That view of the world is not only nonsensical and dated, but also fundamentally anti-democratic. Today’s decision is a long-overdue win for common sense.”

The Trump administration also supported Cox’s case over the past year, telling the Supreme Court that a Sony victory could compel ISPs to “terminat[e] subscribers after receiving a single notice of alleged infringement.”

Sotomayor: Majority dismantled DMCA incentive structure

The Sotomayor concurrence said the majority went too far. “The majority holds that Cox is not liable solely because its conduct does not fit within the two theories of secondary liability previously applied by this Court,” Sotomayor wrote. “In so doing, the majority, without any meaningful explanation, unnecessarily limits secondary liability even though this Court’s precedents have left open the possibility that other common-law theories of such liability, like aiding and abetting, could apply in the copyright context. By ignoring those past decisions, the majority also upends the statutory incentive structure that Congress created.”

As previously noted, the majority found that contributory liability can be shown only if the party induced infringement or if a provided service is tailored to that infringement. Sotomayor said the “majority’s limiting of secondary liability here dismantles the statutory incentive structure that Congress created” in the DMCA.

“Importantly, Congress did not provide that ISPs could never be secondarily liable for copyright infringement,” she wrote. “Instead, it struck a balance by creating incentives for ISPs to take reasonable steps to prevent copyright infringement on their networks, while also assuring ISPs that they do not need to take on the impossible task of responding to every instance of infringement on their networks. The majority’s new rule completely upends that balance and consigns the safe harbor provision to obsolescence.”

Sotomayor said she nonetheless agrees “with the majority that Cox cannot be held liable here for a different reason. Plaintiffs cannot prove that Cox had the requisite intent to aid copyright infringement for Cox to be liable on a common-law aiding-and-abetting theory. I therefore concur in the judgment.”

The majority disagreed that it is upending the DMCA’s safe harbor, which protects providers from liability when they terminate repeat infringers “in appropriate circumstances.” The DMCA does not expressly impose liability for ISPs who serve known infringers, the court majority ruled.

“The DMCA merely creates new defenses from liability for such providers,” Thomas wrote. “And, the DMCA made clear that failure to comply with the safe-harbor rules ‘shall not bear adversely upon… a defense by the service provider that the service provider’s conduct is not infringing.’”

Although Kagan joined the majority opinion today, she said during oral arguments that the DMCA safe harbor would “seem to do nothing” if the court sides with Cox. “Why would anybody care about getting into the safe harbor if there’s no liability in the first place?” she said at the time.

Sony’s Betamax victory hurt it in Cox case

Today’s Supreme Court ruling reversed a decision by the US Court of Appeals for the 4th Circuit. The 4th Circuit “did not suggest that Cox induced its users to infringe” and “did not deny that Cox’s service was ‘capable of substantial lawful use and not designed to promote infringement,’” Thomas wrote. “Rather, the court held that ‘supplying a product with knowledge that the recipient will use it to infringe copyrights is… sufficient for contributory infringement.’”

Thomas said the 4th Circuit holding went beyond the two forms of liability recognized in Grokster and Sony Corp. of America v. Universal City Studios, also known as the Betamax case. The 4th Circuit ruling “also conflicted with this Court’s repeated admonition that contributory liability cannot rest only on a provider’s knowledge of infringement and insufficient action to prevent it,” Thomas wrote.

After reading today’s ruling, Santa Clara University law professor Eric Goldman wrote, “I do note the irony that Sony created the defense-favorable legal standard in 1984 that is now being cited against it in 2026. As the Bible verse goes, ‘You reap what you sow.’”

Goldman explained that “Thomas’ opinion defines ‘tailored to infringement’ as ‘not capable of substantial or commercially significant noninfringing uses.’ This resurrects the Sony v. Universal standard for contributory infringement from over 40 years ago, which largely got put on hold after the Grokster case 20 years ago. Because it’s not been well-explored since 2006, we’re not sure what this phrase means in the modern Internet age.”

Goldman predicted that “there will be substantial confusion in the lower courts trying to figure out how to apply” the “tailored to infringement” standard. “On balance, the old Sony standard should favor future defendants, but copyright owners will invest a lot of money to try to water it down and undermine it,” he wrote.

Sony and other music copyright owners use the MarkMonitor service to trace illegal downloads and uploads to specific IP addresses and send copyright-infringement notices to the users’ Internet providers. Cox told the Supreme Court that ISPs can’t verify whether the notices are accurate and that terminating an account would punish every user in a household where only one person may have illegally downloaded copyrighted files. MarkMonitor sent Cox 163,148 piracy notices during the two-year period covered in the case.

Record labels Sony, Warner, and Universal told the Supreme Court that Cox chose not to terminate repeat copyright infringers to avoid a loss in revenue, despite being sent three or more infringement notices for each subscriber at issue in the case. “[W]hile Cox stokes fears of innocent grandmothers and hospitals being tossed off the Internet for someone else’s infringement, Cox put on zero evidence that any subscriber here fit that bill,” record labels told the court. “By its own admission, the subscribers here were ‘habitual offenders’ Cox chose to retain because, unlike the vast multitude cut off for late payment, they contributed to Cox’s bottom line.”

ISP has “incomplete knowledge” of infringement

At oral arguments, Cox attorney Joshua Rosenkranz said the ISP created an anti-infringement program, sent out hundreds of warnings a day, suspended thousands of accounts a month, and worked with universities to limit infringement. Rosenkranz told the court that “the highest recidivist infringers” cited in the case were universities, hotels, and regional ISPs that purchase connectivity from Cox, rather than individual households.

“According to Cox, it created a system of responding to the notices that it received from MarkMonitor,” Thomas wrote. “After the second MarkMonitor notice for a subscriber’s account, Cox sent a warning to that subscriber. After additional notices, Cox terminated Internet access to that subscriber’s IP address until the subscriber responded to the warning. If it continued to receive notices for that IP address, Cox suspended service until the subscriber called and received a warning over the phone. After 13 notices, the subscriber was subject to termination of all Internet service.” Cox also contractually prohibits subscribers from using the service to infringe copyrights, Thomas noted.

In addition to criticizing the majority’s reasoning today, Sotomayor criticized Cox’s anti-piracy enforcement efforts during oral arguments. “There are things you could have done to respond to those infringers, and the end result might have been cutting off their connections, but you stopped doing anything for many of them… You did nothing and, in fact, counselor, your clients’ sort of laissez-faire attitude toward the respondents is probably what got the jury upset,” she said at the time.

Despite those comments during oral arguments, Sotomayor’s concurrence today said that Sony did not prove that Cox knows specific users will commit infringement. “Cox supplies Internet connections to a wide range of customers, ranging from single users all the way to smaller regional ISPs. When Cox receives a copyright violation notice, however, the notice specifies only which connection was used to infringe, not who used it to commit infringement,” she wrote.

For single homes, Cox has no way “to know if the infringer was a neighbor who might have the Wi-Fi password,” Sotomayor said, also noting that Cox doesn’t have control over regional ISPs that resell Cox network connectivity. “Given this degree of removal from the infringing activity and Cox’s incomplete knowledge, Cox cannot be found to have intended to aid in any specific instance of infringement committed using the connection that Cox provides to the regional ISP,” Sotomayor wrote. “The same is true for connections Cox provides to university housing, hospitals, military bases, and other places that are likely to have many different users.”

Justice Alito agreed with Cox that Sony’s demands for cracking down on piracy at universities were excessive and described Sony’s demands as unworkable. He said during oral arguments that if an ISP tells a university, “a lot of your 50,000 students are infringing… the university then has to determine which particular students are engaging in this activity. Let’s assume it can even do that, and so then it knocks out 1,000 students and then another 1,000 students are going to pop up doing the same thing. I just don’t see how it’s workable at all.”

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Jon Brodkin Senior IT Reporter
Jon is a Senior IT Reporter for Ars Technica. He covers the telecom industry, Federal Communications Commission rulemakings, broadband consumer affairs, court cases, and government regulation of the tech industry.
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