When does an internet service provider, a platform or a technology supplier become legally responsible for copyright infringement committed by its users? The question has been litigated for decades, but the U.S. Supreme Court’s decision in Cox Communications, Inc. v. Sony Music Entertainment, 146 S.Ct. 959, has recalibrated the law in the United States.  In an IPIC webinar I participated in today, Mass Copyright Infringement, Liability and Enforcement: Cox v. Sony and Canadian Approaches, I compare that decision with the different toolkit Canadian law offers rights holders and intermediaries. I was pleased to appear with Richard Pfohl (GC Music Canada who moderated the panel), Krstina Milbourt (Managing Counsel, Rogers ) and Jacqueline Charlesworth (Partner Bayla Law Group, LLP).

This post summarizes the key points: what Cox v. Sony decided, why knowledge plus inaction is no longer enough in the United States, and how Canadian doctrines of authorization, inducement, enablement, common design and the statutory ISP safe harbours apply to mass online infringement.

A copy of the paper I presented at the webinar can be accessed below.

What the U.S. Supreme Court decided in Cox v. Sony

Writing for the Court, Justice Thomas noted that U.S. law recognizes two categories of secondary copyright liability, “contributory” and “vicarious” liability.   That the case concerned contributory liability. The Court held that a service provider is contributorily liable for a user’s infringement only under two theories:

• Inducement: the provider actively encourages infringement through specific acts, as the file-sharing companies in Grokster did by promoting their software as a tool to infringe.
• Tailoring: the service is not capable of “substantial” or “commercially significant” non-infringing uses.

The Court held that  contributory liability cannot rest on a failure to take affirmative steps to prevent infringement. Cox simply provided internet access, which has many lawful uses, and it had discouraged infringement by sending warnings, suspending service and terminating accounts. Holding Cox liable merely for failing to terminate infringing subscribers “would expand secondary copyright liability beyond our precedents.”

The Court therefore rejected the Fourth Circuit’s rule that supplying a product with knowledge that the recipient will use it to infringe is sufficient for contributory infringement.

The DMCA safe harbour does not imply liability

Sony argued that the DMCA’s repeat-infringer termination condition in 17 U.S.C. § 512(i)(1)(A) presupposes that ISPs can be liable for serving known infringers. The Court disagreed: the DMCA creates defences, not new liability, and § 512(l) provides that failing to qualify for a safe harbour does not bear adversely on a provider’s defence that its conduct is not infringing.

The concurrence: aiding and abetting

Justice Sotomayor, joined by Justice Jackson, concurred in the judgment but would not have confined secondary liability to the two Grokster categories. They would have asked whether common-law aiding-and-abetting principles could apply. Drawing on Twitter v. Taamneh (2023) and Smith & Wesson v. Estados Unidos Mexicanos (2025), they reasoned that aiding and abetting requires intent to help the wrongdoing succeed.

How Canada approaches secondary copyright liability

Canadian law does not use the U.S. labels of contributory and vicarious liability. Instead, liability for another person’s infringement arises through several distinct routes: authorization (a form of direct liability under s. 3(1) and s. 27(1) of the Copyright Act), common-law inducement and procurement, acting in concert under a common design, and the statutory enablement provision in s. 27(2.3).

Authorization

The Copyright Act gives owners the sole right to “authorize” protected acts. Following CCH, to authorize means to “sanction, approve and countenance”, with countenance read in its strongest sense. The Federal Court of Appeal summarized the law in Voltage Holdings, LLC v. Doe #1, 2023 FCA 194.

In SOCAN v. Canadian Assn. of Internet Providers, 2004 SCC 45, the Supreme Court held that authority to download infringing material cannot be imputed to an ISP based solely on providing internet facilities, although notice of infringing content and a failure to take it down may, in some circumstances, support an inference of authorization. In Voltage v. Doe #1, the Court of Appeal held that internet subscribers who continued to share their accounts after receiving notices under the Notice and Notice regime  did not authorize infringement: authorization depends on control over the person who infringes, not control over the technology.

Inducement

In Bell Canada v. L3D Distributing Inc., 2021 FC 832, the Federal Court recognized a common-law cause of action for knowingly inducing copyright infringement by selling pre-loaded set-top boxes. The test, borrowed from patent law, asks whether a direct infringement occurred, whether it was influenced by the inducer’s acts, and whether the inducer knowingly exercised that influence. Teva v. Janssen, 2023 FCA 68, has since clarified that in patent cases influence is not a strict “but for” test and that the knowledge required is knowledge that influence is being exercised. Demirören v. General Entertainment and Music Inc., 2024 FC 1127, confirmed that inducement and authorization are distinct causes of action. However, Professor David Vaver, in an article “David Vaver “Inducing” Copyright Infringement in Canada: Is it a Thing?, has questioned whether copyright infringement can be made out under a theory solely grounded in inducement to infringe.

Enablement: Canada’s online contributory infringement provision

Section 27(2.3) makes it an infringement to provide a service over the internet or another digital network primarily for the purpose of enabling acts of copyright infringement, where actual infringement results. Section 27(2.4) lists factors courts may weigh, including marketing or promotion of the service as an infringement tool, knowledge of significant infringement, whether significant non-infringing uses exist, the ability to limit infringement and steps taken, benefits received, and economic viability absent infringement. In many respects this is the closest Canadian analogue to the Grokster inducement and tailoring categories and has some elements on U.S. vicarious liability.

Aiding and abetting, and common design

Whether a separate tort of aiding and abetting copyright infringement exists in Canada has never been fully considered. Common design, an English tort doctrine, is more developed: it requires more-than-trivial assistance, action in concert under a common design, an actual infringement, and knowledge of the essential facts that make the act wrongful. In Adeia Guides Inc. v. Videotron Ltd., 2025 FC 1725, the Federal Court found Videotron liable for patent infringement on a common design theory, reasoning that one cannot escape liability by subcontracting out part of the infringing act. Canadian courts have also referred to joint infringement in copyright.  There are numerous U.K. and Australian cases that have accepted that a copyright infringement case can be premised on joint liability based on a common design theory. David Vaver in the article referred to above agrees it is a viable cause of action.

Vicarious liability

U.S. vicarious liability attaches where a defendant has the right and ability to supervise infringing activity and a direct financial interest in it, with no knowledge required. In Canada, vicarious liability is generally limited to authorization or other accessorial principles and to specific relationships such as employer and employee or principal and agent. Directors and officers can be personally liable where they deliberately pursue, or are indifferent to the risk of, infringing conduct.

ISP safe harbours and the notice-and-notice regime

The Copyright Modernization Act of 2012 added safe harbours in s. 31.1 for network services, caching and hosting. A provider of network services does not infringe solely by providing the means of telecommunication or reproduction, and a host is protected unless it knows of a court decision that the stored material infringes. Importantly, these safe harbours do not apply to conduct that amounts to enablement under s. 27(2.3).

In Voltage Pictures, LLC v. Salna, 2025 FCA 131, the Federal Court of Appeal stated that the s. 31.1 safe harbours insulated ISPs from authorization liability.

Reverse class actions against BitTorrent users

Voltage v. Salna also tested a novel enforcement tool: a reverse (defendant) class action against a class of internet subscribers whose IP addresses were detected sharing Voltage’s films over BitTorrent. The authorization claim alleged that subscribers failed to take reasonable steps to prevent infringement on their accounts.

Certification failed on preferable procedure. Being a subscriber does not prove infringement or authorization, consistent with Voltage v. Doe #1, so who uploaded the films and whether each subscriber authorized that use would need to be proved person by person. Mr. Salna, for example, provided internet access to tenants.

The decision does not foreclose reverse class actions. They remain procedurally available under the Federal Courts Rules, the courts adapted the certification test for defendant classes rather than rejecting it, and a class defined by provable infringing conduct, with liability turning on genuinely common questions, could fare better.

Key takeaways

• In the United States, after Cox v. Sony, contributory liability requires intent shown by inducement or a service tailored to infringement. Knowledge of infringement and a failure to terminate subscribers is not enough.
• Canada has no direct equivalent of U.S. contributory or vicarious liability, but rights holders can pursue authorization, inducement, common design and statutory enablement claims, subject to the caveats noted above.
• Canadian authorization law, like Cox, does not impose liability merely for providing neutral technology or internet access with knowledge of infringement, although indifference after notice can matter on the facts.
• Reverse class actions against subscribers face serious certification hurdles, but the door is not closed for better-designed classes.

Frequently asked questions

What did the Supreme Court decide in Cox v. Sony?

It held that Cox Communications was not contributorily liable for its subscribers’ music piracy. Contributory liability requires that the provider intended its service to be used for infringement, shown by inducement or by a service tailored to infringement. Knowledge plus a failure to terminate infringing accounts is insufficient.

Can an intermediary be liable for copyright infringement in Canada?

Merely providing internet access does not make an ISP liable, and s. 31.1 of the Copyright Act provides safe harbours for network services and hosting. Liability can still arise through authorization on particular facts, inducement, common design, or enablement under s. 27(2.3), which the safe harbours do not cover.

Is an internet subscriber liable for others’ downloads on their account?

Not merely by being the account holder. In Voltage v. Doe #1, the Federal Court of Appeal held that continuing to share internet access after receiving notices does not alone amount to authorizing infringement.

What is the enablement provision in the Canadian Copyright Act?

Section 27(2.3) makes it an infringement to provide an online service primarily for the purpose of enabling copyright infringement, where actual infringement results. Section 27(2.4) lists factors such as promotion of the service, knowledge, no significant non-infringing uses and the ability to limit infringement.

A copy of my paper with more infortmation can be accessed below.