3M Co. and DuPont Co. settled their patent dispute over a process of making protective coatings including Teflon that are free of a chemical suspected of causing cancer, according to Bloomberg. The companies submitted a filing in federal court in Minneapolis seeking dismissal of the U.S. suit, filed in March. DuPont and 3M were among companies that agreed to eliminate perfluorooctanoic acid, or PFOA, from products including Teflon by 2015 amid government and consumer concern that the chemical may harm people. DuPont has said PFOA has mostly been removed from products introduced since 2007, while 3M said it completed the phase-out of last year. 3M said it filed the complaint after DuPont rejected offers to license the patent, which was issued in April 2008 and covers a way to make aqueous Teflon coatings that are effectively free of PFOA. The agreement to eliminate PFOA was made after an Environmental Protection Agency scientific advisory panel said PFOA is a likely human carcinogen, based on animal studies.