OREANDA-NEWS. Severstal North America, a subsidiary of OAO Severstal, announced that the U.S. District Court in Delaware found in summary judgment that ArcelorMittal’s reissue patent for aluminum coated steel sheet for hot stamping not infringed by Severstal Dearborn, LLC and the other defendants.

The District Court Judge stated the reissue patent was invalid because it was improperly broadened long after the permissible time period within which a patent may be broadened.

The Court’s Opinion states, “There can be no doubt that ArcelorMittal pursued its reissue patent as an intentional strategy to avoid the consequences of this court's narrow claim construction, with the ultimate goal of capturing more acts of infringement under the broadening scope of [the reissue patent]. Although such a strategy would have been perfectly legitimate if pursued within two years from the grant of the '805 patent, the court concludes that ArcelorMittal's post-trial strategy offends the fundamental purpose [of] § 251.”

Martin Szymanski, Vice President, General Counsel, Severstal North America expressed his satisfaction with the U.S. Court’s decision to uphold Severstal’s right to continue producing aluminum boron steel for hot stamping. “The District Court’s ruling once again invalidates the ArcelorMittal patent relative to this material. This summary judgment further solidifies Severstal’s position that it can produce the aluminum coated steel sheet designed for high strength applications.”

For reference, in 2010, ArcelorMittal brought a lawsuit against Severstal Dearborn, LLC and others claiming patent infringement on aluminum coated steel. In January 2011, the court held that the ‘805 patent was invalid and that all defendants were not infringing; ArcelorMittal appealed. The Court of Appeals for the Federal Circuit affirmed a ruling that the patent was invalid due to obviousness, but remanded the case back to the District Court for a limited trial based on a new construction of one of the claim terms. In the meantime, ArcelorMittal had the patent reissued with new claims, effectively rendering the original ‘805 patent unenforceable.