The US Court of Appeals for the Federal Circuit posted its decision regarding the patent lawsuit brought against AK Steel, Severstal Dearborn and Wheeling-Nisshin by ArcelorMittal France and ArcelorMittal Atlantique et Lorraine. Previously, a jury verdict found that the defendants did not infringe ArcelorMittal's US patent for aluminum-coated, boron-bearing carbon steel, used primarily in high-strength automotive applications. ArcelorMittal challenged the court's "claim construction and jury's verdict."
The court said that a new trial is now required because the district court's "claim construction error prevented the jury from properly considering ArcelorMittal's evidence of commercial success."
In a press release Monday, AK Steel noted that the Court of Appeals affirmed a basis for the jury finding of no infringement, but reversed certain findings related to the validity of the patent and remanded the case for further proceedings. Those proceedings include a new trial with respect to AK Steel's claims that the patent is also invalid.
AK Steel said that, regardless of the outcome of the new trial on the validity of the patent, the Court of Appeals decision will allow the company to continue to offer the product for sale to customers in the United States.