On Monday Kohler Co. sued Amersink, Inc., alleging infringement of Kohler’s design patents for kitchen sinks. The unique “Large D-Bowl” and “Double Equal Undercounter” Kitchen Sinks, Kohler alleges in the compliant filed in the Eastern District of Wisconsin Federal Court, are protected by design patent. Amersink’s versions “are inferior quality, deeply discounted, imitations of Kohler’s sink designs” says Kohler.