Contributory Infringement in Copyright, Patent, and Trademark Law: A Litigation Primer

Contributory infringement is the term courts use for one form of secondary liability: a party that did not infringe directly but, in the words of the opinions discussed below, knowingly contributed to someone else’s infringement. The doctrine exists in copyright, patent, and trademark law. In each, the authorities describe the same three parts: a direct infringement by a third party, knowledge on the defendant’s part, and a contribution that made the infringement possible. What differs is how each body of law defines knowledge and contribution. Because the defendant in a software dispute is usually a platform, a tool, or a component supplier, the technical questions are often central: what the software does, who controls it, and whether it has uses beyond infringement.

What Is Contributory Infringement?

The opinions and the statute cited in this primer describe three recurring elements:

1. Direct infringement by someone else. The Supreme Court held in Aro Mfg. Co. v. Convertible Top Replacement Co., 365 U.S. 336 (1961), that there can be no contributory infringement of a patent without a direct infringement, and courts apply the same requirement in copyright and trademark cases.
2. Knowledge. The defendant knew of the infringement, or in some formulations should have known. Each doctrine states this differently, as the sections below describe.
3. Contribution. The defendant supplied something the infringement depended on: a product, a service, a component, or a platform.

Contributory Copyright Infringement

The formulation courts most often quote comes from Gershwin Publishing Corp. v. Columbia Artists Management, Inc., 443 F.2d 1159 (2d Cir. 1971): one who, with knowledge of the infringing activity, induces, causes, or materially contributes to another’s infringing conduct may be held liable as a contributory infringer.

Three later decisions describe how that test applies to technology:

• Sony Corp. v. Universal City Studios, Inc., 464 U.S. 417 (1984). The Supreme Court held that selling a product capable of substantial non-infringing uses does not by itself make the seller a contributory infringer, borrowing the “staple article of commerce” principle from patent law.
• A&M Records, Inc. v. Napster, Inc., 239 F.3d 1004 (9th Cir. 2001). The Ninth Circuit held that where a service operator has actual knowledge of specific infringing material on its system and fails to act, Sony does not protect it. The court distinguished a product sold once from a service the defendant continues to operate and control.
• Metro-Goldwyn-Mayer Studios Inc. v. Grokster, Ltd., 545 U.S. 913 (2005). The Supreme Court held that one who distributes a product with the object of promoting its use to infringe, shown by clear expression or other affirmative steps, is liable for the resulting infringement. The opinion calls this the inducement theory and points to evidence of intent such as marketing and internal communications.

The Ninth Circuit added a further refinement in Perfect 10, Inc. v. Amazon.com, Inc., 508 F.3d 1146 (9th Cir. 2007), holding that a service with actual knowledge that specific infringing material is available using its system, which could take simple measures to prevent further damage but continues to provide access, may be contributorily liable.

Where the technical questions are. In these cases the expert is typically asked what the accused system does, how it was designed or configured, what the operator could see (logs, moderation tools, filtering capability), and whether the simple measures a plaintiff proposes were in fact available. Peer-to-peer architecture, content fingerprinting, and takedown handling are common subjects of testimony.

Contributory Patent Infringement (35 U.S.C. § 271(c))

Patent law states the doctrine in the statute. Section 271(c) provides that whoever sells, offers to sell, or imports a component of a patented machine, manufacture, combination, or composition, or a material or apparatus for use in practicing a patented process, is liable as a contributory infringer if the component constitutes a material part of the invention, the seller knows it is especially made or especially adapted for use in an infringement of the patent, and it is not a staple article or commodity of commerce suitable for substantial non-infringing use.

The opinions construing the section add the following:

• Direct infringement is required. Aro I (365 U.S. 336) held that there can be no contributory infringement absent direct infringement by someone.
• Knowledge covers the patent and the infringement. Aro Mfg. Co. v. Convertible Top Replacement Co. (Aro II), 377 U.S. 476 (1964), and Global-Tech Appliances, Inc. v. SEB S.A., 563 U.S. 754 (2011), read section 271(c) to require that the defendant knew the component was especially adapted for a use that infringes a patent. Global-Tech also held that willful blindness satisfies the knowledge requirement.
• Substantial non-infringing use is written into the statute. In software cases it is frequently where the technical dispute concentrates.
• A software feature can be the component. In Ricoh Co. v. Quanta Computer Inc., 550 F.3d 1325 (Fed. Cir. 2008), the Federal Circuit rejected the argument that bundling an infringing software component with non-infringing features immunizes the product, and examined the component itself.

Section 271(b) covers active inducement of infringement, the patent analogue to Grokster, and the two subsections are often pleaded together.

Where the technical questions are. Whether the accused component is especially adapted to the patented use. Whether it has substantial non-infringing uses, which is a factual question about what the software actually does across its configurations and how it is used in practice. Whether the component is a material part of the claimed combination. Source code review, configuration analysis, and usage or telemetry data are the typical evidence.

Contributory Trademark Infringement

Trademark law’s test comes from Inwood Laboratories, Inc. v. Ives Laboratories, Inc., 456 U.S. 844 (1982). The Supreme Court held that a manufacturer or distributor is contributorily liable if it intentionally induces another to infringe a trademark, or if it continues to supply its product to one whom it knows or has reason to know is engaging in infringement.

Courts have applied Inwood to services, including online platforms. In Tiffany (NJ) Inc. v. eBay Inc., 600 F.3d 93 (2d Cir. 2010), the Second Circuit held that generalized knowledge that infringement occurs on a platform is not enough. The operator must have contemporary knowledge of specific infringing listings and fail to act.

The technical questions in trademark cases are typically narrower: what the platform knew and when, how notices were handled, and what controls existed. They are answered from the same sources: system logs, moderation records, and the platform’s own tooling.

What the Authorities Say, Doctrine by Doctrine

The Role of Technical Expertise

In all three doctrines the contested facts are frequently technical: what the software does, what its operator could see and control, whether an accused component has uses beyond the infringing one, and whether the measures a plaintiff says were available would have worked. A software expert witness examines the system itself, including source code, architecture, configuration, logs, and usage data, and describes what that evidence can and cannot show against the elements counsel must prove or rebut.

Attorneys handling a contributory infringement matter that turns on what software does can discuss the matter with a software expert witness.