The following argument will be available live to the public, both in-person and through online audio streaming. Access information will be available by 9 AM ET each day of argument at: https://cafc.uscourts.gov/home/oral-argument/listen-to-oral-arguments/.
Tuesday, August 5, 2025, 10:00 A.M.
Brita LP v. ITC, No. 24-1098, Courtroom 201, Panel B
This appeal arises from the ITC's reversal of an ALJ ruling that certain imported water filters infringed Brita's patent (U.S. Patent No. 8,167,141) and violated Section 337. Brita's '141 patent relates to gravity-fed water filters for removing lead contaminants in drinking water. In the underlying ITC proceeding, the ALJ determined that the claims-at-issue were valid and infringed. The Commission reversed the ALJ's ruling and found those claims invalid under 35 U.S.C. § 112 for lack of written description, lack of enablement, and indefiniteness. Brita appealed to the Federal Circuit.
On appeal, Brita challenges the Commission's invalidity findings on all three issues. Starting with enablement, Brita contends (1) that the Commission misread the certain specification passages as admitting lack of operability of the invention with certain filters, and (2) that it erred in relying on inventor testimony acknowledging the inventors did not produce prototypes for all filter-media types.
Brita also argues that the Commission's errors in its enablement findings undermine its written description determination as well, because the Commission linked and conflated the two requirements. Brita contends that the intrinsic evidence provides sufficient description for its claims, citing the original claims covering all filter types and parts of the specification stating that the invention applies to commonly known filter types. On indefiniteness, Brita contends that the Commission mischaracterized the claim term "filter usage lifetime" as subjective and erred in dismissing industry recognition, referenced in the specification, of its plain meaning.
The Commission counters that substantial evidence supports the Commission's factual findings on all three issues. Specifically, the Commission points out that Brita's written description argument incorrectly assumes the pertinent art was predictable. According to the Commission, substantial evidence supports the Commission's finding that the art was not predictable and that the patent's limited disclosure of working embodiments does not support the broad claims. On enablement, the Commission similarly argues that the patent's limited disclosure enables only certain filters, not the full scope of the claims. Lastly, on indefiniteness, the Commission contends that the claim term "filter usage lifetime claimed by a manufacturer or seller" lacks an objective validation method and instead depends on the subjective assessment of the manufacturer or seller, which renders the claimed scope uncertain. Urging affirmance of the Commission's determination, Intervenors (respondents in the ITC proceeding) similarly argue that the patent lacks adequate disclosure for the broadly claimed scope.
The Federal Circuit's decision may provide helpful guidance on the assessment of the three patentability requirements under 35 U.S.C. § 112, and how the underlying factual findings overlap or differ.
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