Hamilton Beach Brands, Inc. v. Sunbeam Prods., Inc., No. 12-1581 (Fed. Cir. 2013)Annotate this Case
Hamilton Beach and Sunbeam compete in the small kitchen appliance industry; both sell “slow cookers.” Hamilton Beach’s patent disclosed a “portable” slow cooker with clips to seal the detachable lid of the device on the housing of the cooker and limit leaking during transport. Hamilton Beach’s Stay or Go® slow cooker was a commercial success and increased the company’s market share by more than 30 percent. In response, Sunbeam, the previous market leader, developed the Cook & Carry® and attempted to design around the 831 patent by mounting sealing clips on the lid of the slow cooker rather than on the body. Hamilton Beach filed a continuation that matured into the 928 patent, which claimed a slow cooker with sealing clips on the lid, then filed suit alleging that Sunbeam infringed the 928 patent. The district court found certain claims invalid as anticipated and that Sunbeam did not literally infringe asserted claims of the 928 patent. The Federal Circuit affirmed, finding the asserted claims invalid under the on-sale bar.