The Case: A Power Tool Manufacturer Sued a Competitor Over Patent Infringement

A leading manufacturer of power tools and other home improvement and repair equipment sued a rival toolmaker for patent infringement of three patents. The patents relate to the lithium-ion (Li-ion) batteries used in their handheld power tools. Specifically, the plaintiff asserted that its competitor infringed on its patents for:

  • a battery pack used to power a handheld power tool,
  • the charging unit and casing that connects to and is supported by the handheld power tool, and
  • the Li-ion-based battery cells supported by the housing.

This matter went to trial in United States District Court, E.D. Wisconsin.

The Ask: An Expert With Extensive Experience Working with Power Supplies

DOAR was approached by counsel for the plaintiff to provide consulting and testifying expert witness services in support of the plaintiff’s inventions relating to the power management of tools involving Li-ion battery technology. The matter required a highly credentialed technical expert with experience in power supplies and the underlying technology in Li-ion batteries. The expert would be asked to consult with counsel on validity issues in the matter, provide an expert report and deposition, and testify in court.

Why DOAR was Best Suited to Meet the Expert Witness Needs:

In anticipation of a high demand for expert witnesses in emerging technologies like next-gen batteries and power management, DOAR recruited and retained highly credentialed academics and industry executives to support clients in litigation. For this case, DOAR recommended an affiliate expert with nearly 50 years of experience in power electronics, power supplies, and electromechanical systems. Our expert received a Ph.D. from the Massachusetts Institute of Technology, is a Life Member of the IEEE, and has intimate knowledge of power management systems with 16 patents in the field of electronic power conversion. He also has served as an expert witness in more than a dozen cases.

As a result of our expert’s consultation and expert witness testimony, a federal jury sided entirely with our client in finding that the defendant had infringed claims in the three patents, covering different aspects of power management and lithium-ion battery technology. Furthermore, the jury’s verdict awarded $27.8 million to the plaintiff, citing that it would be a reasonable royalty for the defendant’s use of the work.

For more information about how DOAR can help, contact us to discuss your expert witness needs. Follow us on LinkedIn and Twitter to stay up-to-date on our latest insights.

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