1920 (2015), was a 2015 decision by the United States Supreme Court pertaining to the standard for induced patent infringement.

Justice Antonin Scalia dissented from the second point, arguing that, in his view, a good faith belief in a patent's invalidity should constitute a defense to a charge of induced infringement.

The jury at the second trial subsequently found that Cisco had, in fact, induced infringement of the '395 patent and ordered it to pay $63.8 million in damages.

Judge Pauline Newman of the Federal Circuit however criticized this ruling and argued that a good faith belief as to the invalidity of a patent was not a defense to induced infringement.

§ 282, a patent is presumed valid such that allowing a good faith belief of invalidity to act as a defense would undermine that presumption.

Finally, the Court noted that to rule otherwise would encourage litigants to develop post-hac, litigation-driven invalidity theories solely to escape a finding of induced infringement.

[4] Finally, the Court, in a somewhat unusual fashion, devotes a final section of the opinion to a discussion of non-practicing entities, such as patent trolls, and notes that precluding this defense does not provide plaintiffs with free license to accuse companies of induced infringement and that defendants have many avenues with which to attack the validity of patents.