Skip to main content
Commercial Litigation and Disputes Update

U.S. Supreme Court Clarifies Standard for Contributory Copyright Liability

March 27, 2026

On March 25, 2026, for the first time in decades, the U.S. Supreme Court addressed the scope of contributory copyright liability for service providers in Cox Communications, Inc. v. Sony Music Entertainment. The Court held that an internet service provider (ISP) is contributorily liable for infringement by its users only where the provider intended that its service be used for infringement and that such intent may be established only by showing either that the ISP induced the infringement or that it specifically tailored its service to infringing uses and has no substantially noninfringing use. In doing so, the Court rejected a broader standard for contributory infringement applied by the U.S. Court of Appeals for the Fourth Circuit and reversed a judgment imposing liability on an ISP based on its continued provision of service to known infringers.

Background

Cox Communications, Inc. (Cox), is an ISP that serves approximately 6 million subscribers, each associated with an internet protocol (IP) address.1 Many users may share a particular IP address; for example, multiple individual users in a household, coffee shop, or college dormitory may share a single IP address.2 ISPs such as Cox know which IP address corresponds to which subscriber’s account, but they cannot distinguish one individual user from another or directly control how their internet services are used.3

Sony Music Entertainment and other major music copyright owners enlisted a third-party vendor to track infringement of its copyrights across the Internet and to send notices of infringement identifying IP addresses associated with alleged copyright violations.4 Over a roughly two-year period, the vendor sent Cox more than 160,000 such notices reporting infringing activity linked to Cox subscribers.5

Cox maintained a policy for responding to notices of infringement that included escalating measures such as warnings and temporary suspensions.6 After 13 notices, the subscriber was subject to termination of all internet service.7 The parties disputed the effectiveness and consistency of these measures.8 Sony pointed out that Cox terminated only 32 subscribers for infringement during the relevant period, in contrast to the hundreds of thousands of subscribers terminated for nonpayment during the same period.9 Cox, on the other hand, emphasized that its warning and suspension system ended 98% of identified infringement.10

Procedural History

Sony and other copyright owners sued Cox in the U.S. District Court for the Eastern District of Virginia, asserting that Cox was secondarily liable for its users’ copyright infringement.11 They advanced two theories: (1) contributory liability, based on Cox’s continued provision of internet service to subscribers associated with repeated infringement notices, and (2) vicarious liability.12 A jury found that Cox was liable on both theories and that Cox’s infringement was willful.13 It awarded approximately $1 billion in statutory damages.14

The Fourth Circuit affirmed in part and reversed in part. It affirmed as to contributory liability because Cox continued to provide internet service to known infringers, and “supplying a product with knowledge that the recipient will use it to infringe copyrights is exactly the sort of culpable conduct sufficient for contributory infringement.”15 The Fourth Circuit reversed as to vicarious liability because it concluded that Cox did not “receiv[e] a direct financial benefit from its subscribers’ infringement.”16 The court vacated the damages award and remanded for the jury to reassess damages based on contributory liability alone.17

The U.S. Supreme Court granted Cox’s petition for writ of certiorari as to contributory liability but denied Sony’s petition regarding vicarious liability.18

Majority Opinion

On March 25, 2026, the Court unanimously held that the Fourth Circuit incorrectly affirmed the jury’s verdict finding Cox contributorily liable for its users’ infringing activity. The majority opinion was written by Justice Clarence Thomas and joined by six other justices.

In the opinion, the Court emphasized that a service provider “is contributorily liable for the user’s infringement only if it intended that the provided service be used for infringement.”19 According to the Court, its precedents identify only two ways that intent can be established: where the provider induces infringement through active encouragement or promotion or where the provider offers a service that is effectively tailored to infringing uses because it is not capable of substantial or commercially significant noninfringing applications.20

Applying those principles, the Court rejected the broader standard adopted by the Fourth Circuit, which had treated a provider’s knowledge of infringement, combined with its continued provision of service, as sufficient to establish liability.21 The Court reiterated that knowledge of infringement and insufficient action to prevent it does not, by itself, demonstrate the intent required for contributory liability.22

The Court concluded that Cox’s conduct did not satisfy either theory of contributory liability. 23 The record did not show that Cox had taken steps to induce or encourage infringement, such as promoting its services for infringing uses.24 To the contrary, the Court noted that Cox had implemented measures intended to discourage infringement, including warnings, suspensions, and terminations.25 Nor could Cox’s internet service be characterized as tailored to infringement. As the Court explained, “Cox simply provided Internet access, which is used for many purposes other than copyright infringement.”26

The Court also briefly addressed the role of the Digital Millennium Copyright Act (DMCA). In response to arguments that the DMCA presupposes liability for service providers that continue to serve known infringers, the Court explained that the statute creates safe-harbor defenses; it does not impose liability.27 The Court further emphasized that a provider’s failure to qualify for safe harbor does not preclude it from arguing that its conduct is not infringing.28

Concurring Opinion

Justice Sonia Sotomayor, joined by Justice Ketanji Brown Jackson, concurred in the judgment but took a different view of the governing legal framework. The concurrence expressed concern that the majority’s reasoning precludes other common-law theories of secondary liability, such as aiding and abetting.29 In the concurring Justices’ view, precedent may leave room for additional bases of liability, although they agreed that the record in this case did not support liability under any such theory.30

The Supreme Court’s decision in Cox Communications, Inc. v. Sony Music Entertainment clarifies the role of intent in contributory copyright liability and rejects a standard based solely on knowledge and continued provision of services. The decision provides important guidance for courts and litigants while leaving open questions regarding the potential scope of other theories of secondary liability.

 


 

Cox Commc’ns, Inc. v. Sony Music Ent., No. 24-171, slip op. at 3 (U.S. Mar. 25, 2026).
Id.
3Id.
4Id. at 4.
5Id.
Id.
Id.
Id. at 5.
Id.
10Id.
11 Id.
12Id.
13Id. at 5-6.
14Id.
15 Sony Music Ent. v. Cox Commc’ns, Inc., 93 F.4th 222, 236 (4th Cir. 2024).
16Id. at 233.
17Id. at 241.
18 Cox Commc’ns, slip op. at 6.
19 Id. at 7.
20 Id. at 7-8.
21Id. at 9-10.
22Id. at 10.
23 Id. at 9.
24Id.
25Id.
26 Id.
27Id. at 10.
28 Id.
29Id. at 1 (Sotomayor, J., concurring).
30 Id. at 4-5, 13.

弁護士広告—Sidley Austin LLP はグローバルな法律事務所です。当事務所の所在地および連絡先情報は、www.sidley.com/en/locations/offices に掲載されています。

Sidley は、本情報をクライアントおよび関係者の皆様へのサービスとして、教育目的のみに提供しています。本情報は、法的助言として解釈または依拠されるべきものではなく、また弁護士と依頼者の関係を生じさせるものでもありません。読者は、専門家の助言を求めることなく本情報に基づいて行動すべきではありません。Sidley および Sidley Austin とは、www.sidley.com/disclaimer に記載のとおり、Sidley Austin LLP およびその関連パートナーシップを指します。

© Sidley Austin LLP

お問い合わせ

この Sidley Update に関してご質問がある場合は、通常ご担当されている Sidley の弁護士、またはご連絡ください。