In Kaneka Corporation v. Zhejiang Medicine, the U.S. District Court for the Central District of California held that expert testimony alone was sufficient to avoid summary judgment of indefiniteness under 35 U.S.C. § 112 ¶ 2, even though both parties' experts agreed there were several ways to perform the claimed step and even though the intrinsic record did not identify any particular method for performing the claimed step. No. CV 11-02389 SJO (SHSx), slip op. (Apr. 5, 2018 C.D. Cal.) The court's analysis hinged on the U.S. Supreme Court's Nautilus v. Biosig Instruments decision that a patent is invalid for indefiniteness "if its claims, read in light of the specification delineating the patent, and the prosecution history, fail to inform, with reasonable certainty, those skilled in the art about the scope of the invention." According to the court, the experts agreed that those of ordinary skill would have known of the several ways to perform the claimed step, and because the movant had not shown that selection of any of those methods would be "outcome-determinative" in performing the claimed step, summary judgment should be denied.

The disputed claim step required measurement of "70 mole %" in coenzymes Q10. The parties agreed that the measurement of the 70 mole percent involved: (1) collecting a sample, (2) handling (e.g., storing) the sample, and (3) testing the sample. The parties agreed that the testing step was disclosed in the specification, but defendants contended that the first two steps — collecting and handling the sample — were not adequately disclosed in the specification, and the claim was therefore indefinite.

The court agreed that the "intrinsic evidence [does not] reveal ... how a sample should be collected or handled prior to testing the sample." But, the parties' experts agreed that several methods could be used to perform the claimed step, including freezing, refrigeration and adding acid or solvents. The court held that any of these methods would suffice to meet the required collecting and handling of the sample, but that a genuine dispute existed as to which of the methods to use and how long the sample should be stored prior to testing.

Although the defendants provided evidence showing that applying the different methods for different durations can lead to different mole percent measurements, the court denied summary judgment, holding that the defendants failed to show that selecting one of the several known methods would be outcome-determinative in performing the claimed step.

Patent litigators should be cognizant of Kaneka and the increased importance of expert testimony in indefiniteness analysis. Even where a claim limitation finds no support in the intrinsic record, expert opinions can provide adequate support to withstand an indefiniteness challenge. Litigators should perform a thorough indefiniteness analysis prior to expert discovery to make certain that their expert does not provide opinions that would undermine any indefiniteness grounds. Further, when moving for summary judgment under indefiniteness, litigators should be prepared to identify why the intrinsic record's lacking disclosure is outcome-determinative in performing the claimed step.

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