Infringement Under 35 U.S.C. § 271 et seq.

Patent infringement in the United States is governed by 35 U.S.C. § 271 et seq.

(a) Except as otherwise provided in this title, whoever without authority makes, uses, offers to sell, or sells any patented invention, within the United States, or imports into the United States any patented invention during the term of the patent therefor, infringes the patent.

Section (a) quoted above refers to direct infringement, but patent infringement can also be found for indirect infringement, as contributory infringement or inducement to infringe. Liability for contributory infringement arises when one "sells within the United States... a component of a patented machine... knowing the same to be especially made or especially adapted for use in an infringement of such patent, and not a staple article or commodity of commerce suitable for substantial non-infringing use" . Liability for inducing infringement arises when one acts in a manner that actually induces infringement , and the actor knew or should have known that his actions would induce direct infringement . Both contributory infringement and inducement to infringe are dependent upon the proof of direct infringement by some other party. There can be no indirect infringement without direct infringement . During the litigation, the patent claims are presumed to be valid, and invalidity must be proven on a claim by claim basis by clear and convincing evidence .

There is also case law support for joint infringement, even for parties that are not technically contributory infringers of inducement infringers. In the 2006 case, On Demand Mach. Corp. v. Ingram Indus. , the Federal Circuit found no reversible error in the following jury instruction read by the District Court:

It is not necessary for the acts that constitute infringement to be performed by one person or entity. When infringement results from the participation and combined action(s) of more than one person or entity, they are all joint infringers and jointly liable for patent infringement. Infringement of a patented process or method cannot be avoided by having another perform one step of the process or method. Where the infringement is the result of the participation and combined action(s) of one or more persons or entities, they are joint infringers and are jointly liable for the infringement.

The Court gave no support for its holding, but there is support for vicarious patent liability given sufficient intent .

In order to prove vicarious liability for indirect infringement, a plaintiff who demonstrates direct infringement must also establish that the defendant possessed the requisite knowledge or intent to be held vicariously liable. [citations omitted]

There is also support in other circuits for finding joint liability for patent infringement. For example, co-defendants can also be found jointly liable for patent infringement under the theory that the parties were joint tortfeasors , and officers or directors of a company can be held liable for the company's patent infringement .

When one who is an officer of a corporation personally or individually participates in the manufacture or sale of the infringing article -- that is, acts other than as an officer -- or when he uses the corporation as an instrumentality to carry out his own wilful [sic] and deliberate infringements, or when he knowingly uses an irresponsible corporation for the purpose of avoiding responsibility for the damages resulting from patent infringements, he is liable jointly with the company.