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This post originally appeared on Jurist.
It is not always clear exactly when a patent is infringed. People typically think of infringement in a black and white manner as the unauthorized use of another person's invention. However, infringement becomes more complicated for method patents. A method patent—unlike a regular patent—involves several steps a user must perform to achieve a particular result. But what if one user does not perform all of those steps? What if instead one user performs some of the steps, causing another person to perform the other steps? This concept, known as induced infringement, was dealt with by the Supreme Court in Limelight Networks, Inc. v. Akamai Technologies, Inc.
The facts of Limelight are fairly straightforward. Akamai was the exclusive licensee of a complicated, multistep method involving Internet content delivery. The patent claimed a method whereby users would designate components to be stored ("tagged") on servers. Limelight was a competitor that provided a similar service but required its customers to tag their own files. Limelight performed all but one of the steps patented by Akamai. Akamai sued Limelight for patent infringement and received a favorable verdict—including $40 million in damages—in the Federal District Court.
Two years after Akamai's victory, the Federal Circuit decided Muniauction, Inc. v. Thomson Corp. Like in Limelight, the defendant in Muniauction performed all but one of the steps of the plaintiff's method patent and left the remaining step to its customers. Muniauction held that where multiple parties are involved, direct infringement—using a patent without authority—is required before induced infringement can be considered. In such situations, direct infringement requires that one party directly infringed the entire method or exercised control over the entire process. The Federal Circuit consequently held that the defendant was not liable for infringement as it neither performed all the steps of the plaintiff's patent nor exercised control over the process when its customers carried out the remaining steps.