Supreme Court Reverses Fourth Circuit In $1 Billion Copyright Case: What ISPs And Digital Service Providers Need To Know About Secondary Liability After Cox v. Sony Music

On March 25, 2026, the Supreme Court of the United States reversed the Fourth Circuit’s judgment upholding contributory copyright liability in Cox Communications, Inc. v. Sony Music Entertainment, 607 U.S. ____ (2026), and remanded the case, in which a jury had awarded $1 billion in statutory damages. The Court held that an internet service provider (“ISP”) is not contributorily liable for its subscribers’ copyright infringement merely because it continued to provide service to IP addresses associated with known infringement.

Background
Cox Communications is an ISP serving approximately six million subscribers. Sony Music and other major music copyright owners enlisted MarkMonitor, a monitoring service, to track infringement and trace it to particular IP addresses. During the roughly two-year period at issue, MarkMonitor sent Cox over 163,000 notices identifying IP addresses associated with infringement. Cox employed a graduated response system, sending warnings, suspending service, and subjecting repeat offenders to termination after escalating notices, but Sony emphasized that Cox terminated only thirty-two subscribers for infringement during the claim period. 

The jury found for Sony on both contributory and vicarious liability theories, found Cox’s infringement willful, and awarded $1 billion in statutory damages. The Fourth Circuit affirmed on contributory liability but reversed on vicarious liability, finding no direct financial benefit from infringement, and vacated the damages award for reassessment.

Supreme Court Opinion
Justice Thomas, writing for a seven-Justice majority (with two justices concurring in the judgment), held that contributory copyright liability requires proof that the provider intended its service to be used for infringement, which can be established in only two ways: (1) if the provider induced infringement through specific acts, or (2) if the service was tailored to infringement, meaning it is not capable of substantial or commercially significant noninfringing uses. 

Applying both prongs, the Court found neither was satisfied. Cox “repeatedly discouraged copyright infringement by sending warnings, suspending services, and terminating accounts,” and its service “simply provided Internet access, which is used for many purposes other than copyright infringement.” 

The Court rejected Sony’s argument that the DMCA safe harbor would be rendered meaningless by this holding, finding that the DMCA “does not expressly impose liability” but merely creates defenses highlighting the DMCA’s statement that a service provider’s failure to qualify for a safe harbor “shall not bear adversely” on defenses to infringement. 

Justice Sotomayor, joined by Justice Jackson, concurred in the judgment but criticized the majority for “unnecessarily limit[ing] secondary liability.” Rather than applying the majority’s two-prong framework, Justice Sotomayor concurred on the ground that Cox lacked specific knowledge of who committed the infringement—it knew only which IP address was involved—and that “informational gap” was “fatal” to the requisite intent showing. As the concurrence cautioned, by requiring independent volitional conduct—either inducing infringement or providing an infringement-only tool—the majority’s framework arguably risks rendering the DMCA’s “repeat infringer policy” requirements a dead letter, since an ISP would have little incentive to police repeat infringers when mere knowledge of their activity no longer triggers contributory liability.

Takeaways
All nine Justices agreed Cox is not contributorily liable, giving the result strong precedential force despite the doctrinal split. The decision significantly limits knowledge-based contributory liability theories of contributory liability; copyright owners will now need to show active inducement or a service specifically tailored for infringement. ISPs and platform operators should nonetheless maintain robust repeat-infringer policies, as abandoning anti-infringement efforts could support other theories of liability and could invite a legislative response. 

Baker Botts will continue to track developments and provide timely updates and guidance. The case is Cox Communications, Inc. v. Sony Music Entertainment, 607 U.S. ____ (2026) (No. 24–171), and the decision can be found here.

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