In a significant ruling involving lawsuits over “forever chemicals” in firefighting foam, a federal judge refused to grant summary judgment to 3M and other companies, based on a government-contractor defense.

Friday’s ruling allows lawsuits to move forward alleging aqueous film-forming foams made by 3M and others contained toxic chemicals, called perfluorooctanoic acid and perfluorooctane sulfonic acid, or PFOA and PFOS, which contaminated local drinking water supplies.