An Indiana federal judge has dismissed a long-running patent lawsuit between Knauf Insulation Inc. and Johns Manville Corp., just days before the trial was set to begin. However, Chief U.S. District Judge Tanya Walton Pratt of the Southern District of Indiana declined to vacate a prior ruling on claim construction, arguing that doing so would undermine public interest and waste the significant effort invested in the case.

Knauf Insulation vs Johns Manville Lawsuit  : Dismissal of the Case

On August 16, Knauf Insulation and Johns Manville jointly filed for dismissal, which was granted by Judge Pratt. The case, initiated in 2015, involved claims that Johns Manville infringed seven of Knauf's patents with its formaldehyde-free insulation products, EasyFit and Flex-Glass. Although the case is now dismissed, the court's previous summary judgment and claim construction order that invalidated claims related to six of the seven patents will remain on the books.

Judge Pratt's Rationale

In her Thursday opinion, Judge Pratt explained that vacating the earlier claim construction order would not serve the public interest, noting that it would promote "dice rolling" in future patent disputes, where litigants could prolong cases in hopes of getting unfavorable decisions vacated after settling. She referenced the U.S. Supreme Court's 1994 decision in U.S. Bancorp Mortgage Co. v. Bonner Mall Partnership, which held that rulings should not be vacated in cases that settle after an appeal is filed.

Judge Pratt emphasized that a significant amount of time and effort had been invested in resolving the case, with the court and parties producing "thousands of pages of briefing" and months of work leading up to the summary judgment and claim construction order.

Knauf Insulation vs Johns Manville Lawsuit  : Background of the Case

The lawsuit began when Knauf accused Johns Manville of patent infringement concerning its insulation products. Johns Manville, represented by Quinn Emanuel Urquhart & Sullivan LLP and Kilpatrick Townsend & Stockton LLP, managed to stay the case multiple times. Despite these delays, the court eventually ruled in favor of Johns Manville on most of the claims, leaving only a small portion of the dispute unresolved before the parties agreed to settle.

Settlement and Legal Representation

While the terms of the settlement have not been disclosed, both parties have agreed to resolve the dispute outside of court. Knauf Insulation was represented by Woodard Emhardt Henry Reeves & Wagner LLP and Dentons Bingham Greenebaum. Johns Manville’s legal team included attorneys from Quinn Emanuel Urquhart & Sullivan LLP and Kilpatrick Townsend & Stockton LLP.

Despite the dismissal, the court’s prior rulings will remain intact, marking an end to what Judge Pratt described as a "complex dispute" that was "zealously litigated" by both sides.