Yamaha Motor Co., the world's second-largest motorcycle maker, has won a U.S. court ruling that its snowmobile seats didn't violate three patents held by an aftermarket-parts maker in Utah.

U.S. District Judge Dale A. Kimball in Salt Lake City ruled March 13 that Yamaha didn't infringe patents owned by closely held Boss Industries Inc., court papers show.

"They are a big company with a lot of money, and they know darn well they are infringing," Boss founder and Chief Executive Officer Jim Atherley said in a phone interview. "We absolutely plan to appeal."

Boss, based in Pleasant Grove, sued Yamaha in May 2005 over seats and replacement seats on the Iwata City, Japan-based company's Viper and Apex snowmobiles.

"Our company stands behind the integrity of its own patented snowmobile seats, and the court's ruling validates our position," Madeleine Uran, Yamaha's associate general counsel, said in a statement.