Federal Circuit Affirms Product-by-Process Claims Must Be Distinguished by Structure and Function

The Court of Appeals for the Federal Circuit, in Kamstrup A/S v. Axioma Metering UAB, Case No. 21-1923 (Fed. Cir. August 12, 2022), affirmed the Patent Trial and Appeal Board’s construction of independent claims reciting a monolithic polymer structure being cast in one piece.  The phrase “cast in one piece” is a product-by-process limitation and was not granted patentable weight because the product formed from the process could not be distinguished by structure and/or function.