Statutory requirements for claim definiteness are found in 35 U.S.C. § 112(b), which states, "The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or joint inventor regards as the invention." Not long ago, the Court of Appeals for the Federal Circuit (CAFC) decided Guangdong Alison Hi-Tech Co., v. Int'l Trade Comm'n, offering a reminder that mathematical precision is not required to satisfy the definiteness requirement of 35 U.S.C. § 112.
The invention at issue is an aerogel insulation, claimed in U.S. Pat. No. 7,078,359 as comprising "lofty . . . batting". These terms were argued as indefinite by a foreign manufacturer, Alison Hi-Tech Co. The International Trade Commission (ITC) decided the claims at issue are definite, despite the use of "lofty . . . batting", and the CAFC affirmed that decision.
The current judicial standard for definiteness under 35 U.S.C. § 112 is found in Nautilus, Inc. v. Biosig Instruments, Inc., 134 S. Ct. 2120, 2124 (2014). Nautilus states that patent applications are only indefinite if the specification fails to inform, with reasonable certainty, those skilled in the art about the scope of the invention.
The specification of the '359 patent includes multiple examples of commercial products that qualify or further develop the meaning of "lofty . . . batting", including products like Nomex, Kevlar, Spectra, Kynol, Primaloft, Holofil, Thinsulate Lite Loft, and Quartzel. The specification includes a portion that distinguishes the prior art fibrous mats from a lofty batting by describing the minimal open space, higher density, and lack of resilience found in prior art mats as compared to lofty batting. The specification describes the orientation of fibers within lofty batting as being oriented in directions along all three axes, but with only enough fibers along the z-axis to provide resiliency and simultaneously maintain beneficial insulating properties. The specification includes seven examples and test results of aerogel composites manufactured in accordance with the claimed invention. Furthermore, when further scrutinized at the ITC, the claim terms "loft" and "batting" were each found in technical dictionaries to have meanings consistent with their contextual use in the '359 patent.
Alison argued that the specification provides no objective boundary between "some resilience" in the loft batting, which would infringe, and "little [to no] resilience", which would not infringe. Addressing this argument, the CAFC reminds Alison that numerical precision is not required of terms of degree. Furthermore, a person of skill does not need a mathematical formula or definition to determine when a material has negligible resilience.
The takeaway in this case is that taking time to flesh out the specification and ensure claim terms are fully and adequately described pays off down the road. Additionally, although inventors may question the use of terms of degree in claim language, practitioners should remember they are the expert when it comes to claim drafting--and these terms can be highly beneficial if fully supported by the specification.
