Canons of Claim Construction: Cancelled Claims Narrows Construction for Asserted Claims

PatentLawPic290PSN Illinois v. Ivoclar Vivadent, et al. (Fed. Cir. 2008)

PSN’s patent claims a method of making porcelain veneers. PSN sued fourteen companies for infringement, most of whom settled early. The remaining defendants successfully argued that their veneer process was non-infringing.

On appeal, the CAFC looked at claim construction. In a passing breath, the court made the distinction that Phillips applies to “undefined” claim terms:

“We determine the ordinary and customary meaning of undefined claim terms as understood by a person of ordinary skill in the art at the time of the invention, using the methodology in Phillips v. AWH Corp., 415 F.3d 1303, 1312-19 (Fed. Cir. 2005) (en banc).”

Here, the court needed to determine the meaning of the undefined term “ready for mounting.” Relying upon the patentee’s use of the word ‘MAY’ in describing the claimed process, the CAFC held that the term should be rather broadly construed to optionally include ‘finishing’ steps. (Specification: “While still on the statue, the veneer casing may be subject to a finishing treatment to improve the esthetics.”)

The appellate panel noted that, within reason, claims should normally be construed to cover the described embodiments. The panel cautioned however, that each claim does not necessarily cover each embodiment. To the contrary, in some cases unasserted or cancelled claims directed to a particular disclosed embodiment may actually serve as evidence that the scope of remaining asserted claims does not extend to that embodiment.

“[C]ourts must recognize that disclosed embodiments may be within the scope of other allowed but unasserted claims. Likewise, during prosecution, an applicant may have cancelled pending claims but not amended the specification to delete disclosure relevant only to the cancelled claims. In such cases, unasserted or cancelled claims may provide ‘probative evidence’ that an embodiment is not within the scope of an asserted claim.”

Here, although the CAFC reversed on claim construction, it still found that summary judgment of non-infringement was proper.

5 thoughts on “Canons of Claim Construction: Cancelled Claims Narrows Construction for Asserted Claims

  1. 4

    Occasionally when claims are withdrawn in response to a Restriction Requirement, the Examiner will require that the Title and Abstract be “amended to more clearly reflect the invention as now claimed”. For example, when apparatus and method claims are restrictd.

  2. 2

    As a new practitioner, I wonder what the best practice is regarding editing the spec after withdrawing claims. Any comments would be helpful.

  3. 1

    Often one finds a smiley or two hidden in Judge Michel’s opinions. Here he’s writing on dental veneers:

    “When read in context of the claim language and the specification, we find that the district court was incorrect in holding that the description of a preferred embodiment had more bite than the description in the summary of the invention. “

    You can tell a guy who loves his work.

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