Copy of ISP Copyright Infringement Liability: The Supreme Court's Cox v. Sony Ruling Explained

Written by: Brennan Paterson, Lex Tecnica Law Clerk

The Supreme Court’s recent 9-0 decision in Cox Communications, Inc. v. Sony Music Entertainment 607 U.S._(2026) is a clear statement from the Court as it continues to address copyright infringement in a world of instantaneous communication and quickly evolving technology. While the case itself has to do with internet service provider (ISP) liability for copyright infringement by its customers, its real significance lies in how it establishes firm interpretation of contributory infringement in copyright versus public’s access to information on the internet generally.

At the heart of Cox is whether an ISP can be held liable for the infringing activities of its subscribers, specifically when the ISP continues to provide service to users who repeatedly violate copyright.  Under the Copyright Act, infringement is typically straightforward: someone reproduces, distributes, performs, or displays copyrighted material without authorization, violating one of the exclusive rights granted under 17 U.S.C. § 106. But copyright law doesn’t only consider direct infringers.  Contributory infringement (when someone knowingly contributes to or materially participates in infringing activity) has been addressed by the Court before. In Sony Corp. of America v. Universal City Studios, Inc., 464 U.S. 417 (1984) the Court held that manufacturers of home video recording equipment were not liable for contributory copyright infringement simply because their customers might use their products to violate copyright – there was a legitimate use for the equipment by private individuals. In a pre-internet world where the major concern was the physical reproduction of copyrighted media, that legitimate use was found to be of greater import than concerns about pirate videotape distribution. Later, in MGM Studios, Inc. v. Grokster, Ltd., 545 U.S. 913 (2005), the Court began to look at the same question in a post-internet world, finding that a producer of technology could be found liable for copyright infringement if they “induced” that infringement in their users – that is, if you make a product designed and marketed to infringe copyright, you could be held liable for your customers’ actions. 

In this case, Sony and other copyright holders argued that Cox knowing allowed repeat copyright infringers to remain on its network, despite receiving thousands of copyright infringement notices.  Cox, on the other hand, claimed protection under the safe harbor provisions found in 17 U.S.C. § 512. These safe harbors are critical - they shield ISPs from monetary liability for user-generated infringement, provided they meet certain conditions. One of the most important is found in § 512(i), which requires providers to “adopt and reasonably implement” a policy for terminating repeat infringers. The dispute, then, wasn’t about whether or not copyrights had been infringed, but rather whether Cox was responsible for the actions of its users in those infringements.

In determining contributory infringement, courts look for evidence that the defendant knew of the infringing activity and materially contributed to it. In Cox, the Court examined whether Cox’s awareness of repeated violations by specific users amounted to the kind of knowledge that triggers liability. Equally important was whether Cox’s continued provision of internet access constituted “material contribution.” Access to the internet is, after all, the infrastructure that enables file sharing, and when an ISP knowingly maintains access for repeat infringers, that continued service can cross the line from passive facilitation into actionable contribution.  As noted above, Cox relied on the safe harbor provisions in 17 U.S.C. § 512, pointing out that they met the requirements for having a system to address repeat copyright infringers using Cox’s internet service.  The Court, referring to earlier precedent, held that Cox (and other ISPs) are not copyright infringers merely for providing a service with the knowledge that some of their customers will or have infringed on copyrights. The decision reinforced 17 U.S.C. § 512(m), which says that an ISP is not required to “monitor its service or affirmatively seek facts indicating infringing activity”. So even though Sony argued that Cox wasn’t trying hard enough to go after copyright infringers, the Court simply referred back to Congress’ determination that ISPs don’t have to try very hard, actually. ISPs are not required to be gatekeepers that must screen all content flowing across their networks. Instead, they are liable only if they ignore concrete evidence of infringement and fail to follow their own policies. In that sense, the ruling helps preserve the open architecture of the internet. By maintaining the balance between targeted enforcement and limited obligations, the decision supports a system where lawful speech, creative expression, and access to information can continue without excessive interference.

Had the Court found against Cox, however, the consequences for the internet could have been profound. A finding of liability against Cox under these circumstances would likely have pushed ISPs toward aggressive monitoring and enforcement practices, not merely to address clear cases of infringement, but to avoid even the risk of liability. Faced with potential exposure, providers might be forced to adopt overly broad termination policies, cutting off users based on allegations rather than verified violations, or filtering vast amounts of content preemptively. Such a regime would almost certainly have produced a chilling effect on the free exchange of information online, discouraging lawful speech, fair use, and innovation. Users, aware that their access could be curtailed based on automated or unverified claims, might hesitate to share or engage with content altogether. In effect, the internet could have shifted from an open platform for communication into a more tightly controlled and risk-averse environment, fundamentally altering how information flows in the digital age.

Ultimately, Cox reaffirms a critical principle: that contributory infringement must be a matter of intent, rather than ability. This principle will ensure that as technology continues to evolve, the free and dynamic exchange of information online will continue even if copyright holders will have to be more proactive in the defense of their rights.

This article has been reviewed and approved for legal accuracy by Ashlyn Hauber, Esq. It is intended for informational purposes only and does not constitute legal advice.

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