Plastic Foam Constituents Given in Volume (Rather Than Density) are not Indefinite

Reversing a judgment of invalidity under 35 U.S.C. § 112, ¶ 2, the U.S. Court of Appeals for the Federal Circuit has now held that a patent claiming the ingredients for a plastic foam, given in volume, is not indefinite. Marley Mouldings Ltd. v. Mikron Industries, Inc., Case No. 04-1441 (Fed. Cir. Aug. 8, 2005) (Newman, J.).

Marley Mouldings held a patent claiming a material created by combining certain ingredients in proportions cited by "parts (volume)." Marley brought suit against Mikron claiming its process, in which the component substances were defined by weight, not volume. One of the ingredients was wood flour. The parties disagreed as to what density value should be assigned to wood flour in order to convert its measurement from weight to volume. The density was not specified in the patent. The district court ruled the patent was invalid for indefiniteness. Marley appealed.