Federal Circuit Dismisses "Unanswered Questions" and "Claim Language, Standing Alone" Indefiniteness Analysis

On January 27, 2022, the Court of Appeals for the Federal Circuit issued a decision in Nature Simulation Systems Inc. v. Autodesk, Inc., No. 20-2257 (Fed. Cir. Jan. 27, 2022). The Federal Circuit concluded that the district court erred on the legal standard of indefiniteness by focusing exclusively on claim language while ignoring the specification and prosecution history. Judge Newman authored the majority opinion, and Judge Dyk dissented.

Nature Simulation Systems Inc. (NSS) sued Autodesk for infringement of two patents relating to methods of packaging computer-aided data for three-dimensional objects. After a claim construction hearing, the district court held that two claim terms rendered all claims indefinite under 35 U.S.C. § 112(b). NSS argued that the challenged terms were clearly set forth in the specification, but the court dismissed this argument and focused on several "unanswered questions" that remained after reading the claim language. The court concluded that even if these questions are answered in the specification, the definiteness requirement is not met if the questions are not answered in the claims.

The Federal Circuit explained that claims should not be understood exclusively based on the claim language, thereby rejecting the district court’s "claim language, standing alone" approach. The Federal Circuit further rejected the district court’s "unanswered questions" analysis. The court advised that the correct protocol is to consider the words of the claims, the specification, and the prosecution history, as well as extrinsic evidence concerning scientific principles, technical definitions and the state of the art.

Additionally, the Federal Circuit noted that "[a]ctions by PTO examiners are entitled to appropriate deference . . . for examiners are deemed to be experienced in the relevant technology as well as the statutory requirements for patentability." Here, the examiner had previously rejected the claims as indefinite in view of the challenged terms, but ultimately withdrew the rejections after NSS amended its claims. The Federal Circuit criticized the district court for not affording sufficient weight to this resolution of indefiniteness during examination.

This opinion is a reminder that claim language should not be considered in a vacuum, and that the prosecution history, including an examiner’s determinations and actions, should be afforded appropriate weight.