Unreasonable Claim Construction No Defense to Induced Infringement

Posted by Rob Jensen on Aug 31, 2016

In Warsaw Orthopedic v. NuVasive, the Federal Circuit addressed the evidence necessary to establish the “intent” requirement for induced infringement. Even though a party may not be liable for direct infringement of a patent, it may be liable for induced infringement where it encourages another to perform acts that do directly infringe the patent. This case follows on the heels of the Supreme Court’s decisions in Global-Tech and Commil.

What This Means to You

  • Draft claims to cover direct infringers.
  • Intent to induce infringement is fact-specific and will be left to the fact-finder.
  • Lack of intent is not a reliable shield to liability for induced infringement.

Case Background

Warsaw sued NuVasive for patent infringement, and NuVasive counterclaimed for infringement of the ‘236 patent, which describes using electrical stimulus pulses to determine the distance to a nerve during a procedure. On the counterclaim the jury found Warsaw to have induced infringement of the ‘236 patent, and  the Federal Circuit affirmed. However, on appeal, the Supreme Court vacated and remanded the case to the Federal Circuit for reconsideration in view of Commil.

On remand, the Federal Circuit addressed Warsaw’s argument that there was insufficient evidence of its intent to induce infringement. Warsaw conceded it had knowledge of the patent, and there was evidence it instructed doctors to perform the claimed method of electromyography using Warsaw’s devices. Warsaw’s defense was that it had interpreted the claims such that it had a reasonable belief that its devices did not operate in a way that infringes infringement. 

Specifically, Warsaw argued it reasonably interpreted the claim language “stopping the emission of said stimulus signal immediately after said predetermined neuro-muscular response is detected” to mean a complete termination of emission of any and all electrical pulses. Warsaw pointed out its devices do not completely terminate emission of electrical pulses as claimed, as they continue to emit electrical pulses at a low level after a neuromuscular response is detected.

Decision Analysis

On remand, the Federal Circuit again affirmed. The court held that there was substantial evidence in the patent and prosecution history that Warsaw’s claim construction was objectively unreasonable. Therefore, the court did not see a need to vacate the jury’s decision in view of the Supreme Court’s guidance in Commil and Global-Tech.

In Global-Tech, the Supreme Court reaffirmed that induced infringement requires knowledge that the induced acts constitute patent infringement, but that such knowledge can be inferred from the circumstances. Global-Tech held “willful blindness” to facts demonstrating inducement is sufficient to satisfy the knowledge requirement. In Commil, the Supreme Court held that belief of a patent’s invalidity is not a defense to induced infringement.

In reaching its decision, the Federal Circuit pointed to the language of the claim itself, which does not require stopping any and all stimulus signals, only stopping emission of “said stimulus signal,” which the parties had agreed is a signal capable of stimulating a neuromuscular response. The Federal Circuit also pointed out that Warsaw had not advanced such a claim construction earlier in the case, and instead had argued the “stopping” limitation should be construed according to its plain and ordinary meaning.


Although NuVasive was successful at the Federal Circuit, this case serves as a reminder to draft claims to cover competitors as direct infringers. Making a case for induced infringement requires presenting substantial evidence beyond that which is required for direct infringement, which increases expense and allows additional attacks on a verdict on appeal. Inducement cases with intent at issue may not be easily amenable to resolution on summary judgment, as intent to induce infringement is fact-specific and will be left to the fact-finder. Since the question of intent is left to the fact-finder, and intent can be inferred from the circumstances, lack of intent is not a reliable shield to liability for induced infringement.

Wolf Greenfield's CAFC Blog

Here, Wolf Greenfield attorneys summarize and identify key takeaways from recent patent law cases decided by the U.S. Court of Appeals for the Federal Circuit. View past case summaries here.

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This blog is intended to promote thought and debate on developing areas of the law. The opinions, commentary and characterizations of cases provided on this blog are not legal advice and do not represent the opinions of Wolf Greenfield or its clients.