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CAFC Updates


By January 27, 2022No Comments

Nature Simulation Systems, who owns United States Patents Nos. 10,120,961 and 10,109,105, both entitled “Method for Immediate Boolean Operations Using Geometric Facets,” sued Autodesk for infringement. After a claim construction (Markman) hearing at which Autodesk requested construction of eight terms in the claims, the district court ruled the claims invalid as indefinite under 35 U.S.C. § 112(b) based on two of those terms. The district court did not define the two terms; instead, the court held that a claim term is indefinite, as a matter of law, if there are any “unanswered questions” about the term. “Unanswered questions” were suggested by Autodesk’s expert, and district court held the questions raised by Autodesk must be answered, and that the answers must be in the claims.  The CAFC notes that the district court did not construe the claims, did not apply the protocols of intrinsic and extrinsic evidence, and did not resolve the meaning and scope of the challenged claims – – but rather, applied a flawed analysis of validity. The CAFC does its own analysis and finds the prosecution history significant, because the patent examiner had initially rejected the claims on the ground of indefiniteness, and after amendments required by the examiner were made by applicant, the examiner withdrew the indefiniteness rejection relating to the two terms found indefinite. The CAFC concludes that the district court erred on the legal standard for claim indefiniteness, and that on the correct standard indefiniteness under 35 U.S.C. § 112 was not established as a matter of law and the claims are not indefinite. Accordingly, the CAFC reverses and remands. Judge Dyk dissents because in his view the asserted claims are indefinite, there is no reasonable basis in the claims or specification for the majority’s decision, and the fact that a patent examiner introduced the indefinite language does not absolve the claims from the requirements of 35 U.S.C. § 112.

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