Federal Circuit Finds District Court Erred in Concluding Claim Limitations Contradictory
IP Litigation
This links to the home page
FILTERS
RECENT POSTS
The Federal Circuit Is Amenable, Under Certain Circumstances, To Allowing A Patent Owner To Seek Foreign Damages For Domestic Infringement
Federal Circuit Affirms District Court Of Delaware’s Rule 12(b)(6) Dismissal Holding Asserted Claims Unpatentable Under 35 U.S.C. § 101.
Federal Circuit Finds Challenged Claims of Laser Projector Alignment Patent Not Unpatentable

  • Federal Circuit Finds District Court Erred in Concluding Claim Limitations Contradictory
    03/26/2024

    On March 6, 2024, the Court of Appeals for the Federal Circuit (“CAFC”) reversed decisions from the United States District Court for the Western District of Texas in consolidated Case Nos. 6:21-cv-00347 and 6:21-cv-01007, Judge Alan D. Albright, finding the claims of the ’035 patent indefinite. Maxell, Ltd. v. Amperex Technology Ltd., __ F.3d __ (Fed. Cir. March 6, 2024). In its precedential decision reversing and remanding, the CAFC found that the district court erred in finding claim language contradictory and therefore indefinite.

    In consolidated district court cases, patentee asserted infringement of its ’035 patent, and defendant sought a declaratory judgment of non-infringement of the same patent. Defendant also argued invalidity as a defense to the infringement suit. 

    The ’035 patent’s sole independent claim 1 is directed to a lithium-ion battery and recites a positive cathode with at least two lithium-containing transition metal oxides, represented by formulas that include a transition metal element M1. Claim 1 includes two “wherein” limitations relating to M1.  The first reads: “wherein M1 represents at least one transition metal element selected from Co, Ni and Mn.” The second reads: “wherein the content of Co in the transition metal M1 of the formulae (1) and (2) is from 30% by mole to 100% by mole.”

    The district court issued a claim construction order that addressed the two “wherein” clauses and held indefinite the following phrase that combines them: “M1 represents at least one transition metal element selected from Co, Ni and Mn, . . . wherein the content of Co in the transition metal M1 of the formulae (1) and (2) is from 30% by mole to 100% by mole.” The district court reasoned that “the plain language of the claim recites a contradiction,” because the first limitation does not require the presence of cobalt (nickel or manganese suffices), so cobalt is “optional,” whereas the second limitation does require cobalt. Patentee appealed.

    The CAFC found that the district court erred in finding indefiniteness, not because a contradiction in a claim cannot produce indefiniteness, but rather because there is no contradiction in the claim language at issue in the ’035 patent.

    The CAFC reasoned that the two limitations are not contradictory because “[i]t is perfectly possible for a transition metal element to meet both requirements.” The CAFC concluded this was so even though there are intervening limitations between the two “wherein” clauses at issue. In support, the CAFC cited black-letter law establishing that claim language must be read in the context of the full claim.

    The CAFC also took issue with the district court’s interpretation of the first “wherein” limitation as “granting options” which the second limitation “takes back.” The CAFC pointed out that claim limitations do not “grant options.” They “state requirements.” Consequently, “[i]f there are two requirements, and it is possible to meet both, there is no contradiction,” even if one is narrower than the other. If it were otherwise, the CAFC observed, the concept of dependent claims, which by statute must narrow independent claims, would be upended.

    CATEGORIES: Indefiniteness, Section 112

LINKS & DOWNLOADS