The Supreme Court Narrows Contributory Copyright Liability for ISPs in Cox v. Sony Music

The Supreme Court’s March 25, 2026 decision in Cox Communications, Inc. v. Sony Music Entertainment, No. 24-171, 607 U.S. ___ (2026), marks a major clarification of when internet service providers (ISPs) can be held liable for their customers’ online piracy. Sony and other music companies, relying on more than 163,000 infringement notices from monitoring firm MarkMonitor, argued that Cox knowingly kept repeat infringers online to preserve subscription revenue, even while terminating customers for nonpayment. A jury in the Eastern District of Virginia agreed, finding Cox liable for contributory and vicarious infringement and awarding $1 billion in statutory damages. The Fourth Circuit later affirmed contributory liability, reasoning that continuing to provide internet service with knowledge it would be used to infringe was sufficient, while reversing on vicarious liability and remanding for recalculation of damages.

The Supreme Court reversed on contributory liability and narrowed the doctrine. Relying on Sony (Betamax) and Grokster, the Court held that a provider is contributorily liable for users’ infringement only if it intended its service to be used for infringement. That intent, the Court explained, can be shown in only two ways: by inducing infringement through affirmative encouragement, or by offering a service tailored to infringement—one not capable of substantial or commercially significant non‑infringing uses. Because Cox’s broadband service plainly supports countless lawful activities and Cox did not promote piracy, the Court concluded that mere knowledge that some subscribers infringed was insufficient to establish contributory liability.

The Court also rejected Sony’s attempt to leverage the DMCA safe‑harbor regime into a basis for broader liability. Emphasizing that the DMCA is a shield, not a sword, the Court reiterated that the statute creates defenses that limit liability where it would otherwise exist; it does not itself impose new duties or expand secondary liability for ISPs that continue serving known infringers. Taken together, the decision significantly narrows the circumstances under which ISPs and other general‑purpose service providers may face secondary copyright liability, reaffirming that such liability requires clear evidence of inducement or a service designed around infringement.