Supreme Court Overturns Billion-Dollar Copyright Verdict: Knowledge Isn’t Enough for Contributory Copyright Infringement in the Digital Age

On March 25, 2026, the Supreme Court reversed a billion-dollar verdict against Cox Communications, Inc. (“Cox”), holding that an Internet service provider is not contributorily liable for its users’ copyright infringement merely because it continued to provide services to subscribers it knew were associated with infringing activity. Cox Commc’ns, Inc. v. Sony Music Ent., No. 24-171, slip op. (U.S. Mar. 25, 2026).

Cox is an Internet service provider serving approximately six million subscribers. Sony Music Entertainment (“Sony”), along with other major music copyright owners, enlisted an entity called MarkMonitor to detect when their copyrighted works are illegally uploaded or downloaded and to trace the infringing activity to particular IP addresses. During the roughly two-year period at issue, MarkMonitor sent Cox 163,148 notices identifying IP addresses of Cox subscribers associated with infringement. Cox implemented a graduated response system of warnings, service suspensions, and eventual termination, and contractually prohibited subscribers from using their connections to infringe copyrights. The parties dispute the efficacy of Cox’s system — Sony claims Cox only terminated 32 subscribers as repeat infringers (while terminating hundreds of thousands of subscribers for non-payment), while Cox claims its system ended 98 percent of identified infringement.¹

Despite these efforts, infringement of Sony’s copyrighted works continued, and in November 2018, Sony sued Cox in the Eastern District of Virginia, advancing two theories of secondary copyright liability: (1) contributory liability, alleging that Cox was liable for continuing to provide Internet service to subscribers whose IP addresses it knew were associated with infringement; and (2) vicarious liability, alleging that Cox profited directly from the infringement and had a right and ability to supervise the direct infringers.² The jury found in favor of Sony on both theories, found Cox’s infringement willful, and awarded $1 billion in statutory damages.³ Upon Cox’s appeal, the Fourth Circuit affirmed as to contributory liability, reasoning that supplying a product with knowledge that it will be used to infringe is sufficient for contributory infringement, but reversed as to vicarious liability, reasoning that Cox did not receive a direct financial benefit from its subscribers’ infringement.⁴ The Supreme Court took up Cox’s writ of certiorari as to contributory infringement, while denying Sony’s as to vicarious liability.⁵

The Supreme Court unanimously reversed. Justice Thomas delivered the majority opinion, joined by six other Justices, while Justice Sotomayor penned a concurring opinion joined by Justice Jackson. At the outset, the majority held that contributory copyright liability requires a showing that a provider intended its service to be used for infringement, and that the requisite intent can be established in only one of two ways: a plaintiff must show that the service provider either (1) induced the infringement through active encouragement; or (2) sold a service tailored to infringement.⁶ Importantly, the Court drew a distinction between intent that a service be used for infringement and mere intent to provide a service with knowledge that some will use it to infringe. The Court stated plainly that “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.”⁷ Rather, the requisite showing is one of “an affirmative intent that the product be used to infringe” — demonstrated either by actively encouraging that use or by designing a service around it.⁸ In other words, a provider that knowingly supplies a service understanding that some users will misuse it does not, by that fact alone, intend for its service to be used for infringement. According to the Court, these methods of establishing intent directly track patent law, with which copyright law shares a “historic kinship.”⁹ In so holding, the majority squarely rejected the Fourth Circuit’s knowledge-based standard, which had treated “supplying a product with knowledge that the recipient will use it to infringe copyrights” as an independent basis for contributory liability.¹⁰ The Court specifically found that this approach went beyond the two recognized forms of liability and conflicted with the Court’s repeated admonition that contributory liability cannot rest solely on a provider’s knowledge of infringement and insufficient action to prevent it.¹¹

Applying the new framework, the Court found that Cox satisfied neither basis for liability. As to inducement, the Court found that Cox did not encourage infringement and in fact repeatedly discouraged it through warnings, suspensions, and terminations. As to whether Cox provided a service tailored to infringement, the Court quickly determined that Cox’s Internet service was clearly capable of substantial non-infringing uses. Finally, the Court addressed Sony’s argument that the Digital Millennium Copyright Act’s (“DMCA’s”) safe harbor provision, which shields Internet service providers from secondary liability if they implement a policy providing for the termination of repeat infringers “in appropriate circumstances,” would be rendered meaningless if providers cannot be held liable for serving known infringers.¹² The Court rejected this argument, noting that the DMCA does not expressly impose liability on providers who serve known infringers but merely creates new defenses from liability.¹³ The Court further observed that the DMCA itself specifies that failure to qualify for the safe harbor “shall not bear adversely upon . . . a defense by the service provider that the service provider’s conduct is not infringing.”¹⁴

Justice Sotomayor’s concurrence agreed Cox was not liable for contributory infringement, specifically because Sony had not shown that Cox had the requisite intent to aid specific instances of infringement, particularly given that Cox could not determine which specific individuals committed infringement using its network.¹⁵ In the concurrence’s view, secondary liability for copyright infringement must be examined in light of common law rules of liability (such as aiding and abetting). Justice Sotomayor thus criticized the majority for artificially limiting secondary liability to only those cases where the relevant party induced infringement or provided a service tailored to infringement. Drawing on the Court’s recent decisions in Twitter, Inc. v. Taamneh, 598 U.S. 471 (2023), and Smith & Wesson Brands, Inc. v. Estados Unidos Mexicanos, 605 U.S. 280 (2025), Justice Sotomayor applied common-law aiding-and-abetting principles under which intent need not mean a desire that infringement occur — it can be inferred where a provider knows that infringement is “certain, or substantially certain” to result from its continued service. This standard occupies a middle ground: it is more demanding than the Fourth Circuit’s bare-knowledge test (which all nine Justices rejected), but is more flexible than the majority’s inducement-or-tailoring framework. Even under that more accommodating standard, however, the concurrence found Sony’s case fell short because Cox could not identify which individuals were infringing — an “informational gap” that precluded any finding that Cox intended to aid specific acts of infringement.¹⁶ Justice Sotomayor also faulted the majority for “eviscerating” the safe harbor scheme of the DMCA — under such a narrow view of secondary infringement, “ISPs no longer face any realistic probability of secondary liability for copyright infringement, regardless of whether they take steps to address infringement on their networks and regardless of what they know about their users’ activity.”¹⁷

Notwithstanding their disagreement on the proper framework, all nine agreed that knowledge of infringement alone is not enough and that some form of purposeful intent (beyond mere awareness) is required to hold a party secondarily liable for copyright infringement. They disagreed, however, on how that intent may be established. The majority requires intent shown exclusively through inducement or service tailoring, while Justice Sotomayor would also recognize intent inferred from knowledge that infringement is substantially certain to result, consistent with common-law aiding-and-abetting principles. Moreover, the majority’s reliance on patent doctrine in formulating its copyright contributory liability framework appears to signal that this heightened intent standard may not be confined to copyright, but reflects a broader principle the Court considers equally applicable to patent law and potentially other areas of IP.

What This Means for You

This decision significantly raises the bar for establishing contributory copyright infringement. By limiting contributory liability to cases involving inducement or a service tailored to infringement, the Court has effectively insulated providers of general-purpose services from secondary copyright liability based solely on knowledge that users may use those services to infringe. The Court’s express reliance on the “historic kinship” between copyright and patent law also suggests that its reasoning, while rooted in the copyright context, may carry implications for secondary liability analyses across other areas of intellectual property. Notably, all nine Justices converged on the principle that specific intent is essential to secondary copyright liability and that mere knowledge of infringement falls short. The majority’s framework requiring intent to be shown through inducement or tailoring, and expressly rejecting knowledge-based liability, may give patent defendants new arguments for narrowing the scope of inducement under 35 U.S.C. § 271(b), particularly in cases where plaintiffs rely on generalized knowledge rather than evidence of active encouragement. However, Justice Sotomayor’s willingness to infer intent from knowledge of substantially certain consequences suggests that the full Court has not shut the door on all knowledge-adjacent theories across IP. With the case now remanded to the Fourth Circuit, and copyright holders likely to reassess their enforcement strategies in light of this ruling, the practical implications of Cox will continue to develop.

¹Cox Commc’ns, Inc., slip op. at 5.

²Id.

³Id. at 5–6.

⁴Id. at 6.

⁵Id.

⁶Id. at 7.

⁷Id. at 1.

⁸Id. at 8.

⁹Id. at 2.

¹⁰Id. at 9–10.

¹¹Id. at 10.

¹²17 U.S.C. § 512(i)(1)(A).

¹³Cox Commc’ns, Inc., slip op. at 10.

¹⁴Id. (quoting 17 U.S.C. § 512(l).

¹⁵Cox Commc’ns, Inc., slip op. at 1–2 (Sotomayor, J., concurring in the judgment).

¹⁶Id. at 11.

¹⁷Id. at 6–7.

This information is provided by Vinson & Elkins LLP for educational and informational purposes only and is not intended, nor should it be construed, as legal advice.