Saunders Group v. Comfortrac (Fed. Cir. 2007).
Typical use of continuation practice: (1) Patentee files application claiming feature B1 (as the only described embodiment of generic class B). (2) Competitor releases product that would be infringing except for its feature B2. (3) Patentee files continuation that replaces B1 with the generic element B. (4) patent issues. What happens in upcoming litigation?
This scenario, which is exemplified in Saunders Group, raises at least three particular litigation issues listed in order applicability: (1) whether the broad scope of element B has been properly enabled; (2) whether the specific element B1 is an essential element of the invention whose removal would be a violation of the written description requirement discussed in Gentry Gallery; and (3) whether the broad term B should be construed in a limited fashion to avoid problems 1 and 2 (applying the maxim that claims should be construed to preserve validity).
We know from Saunders Group, of course, that it is impermissible to import limitations into a claim even when hoping to preserve validity of the claim. Especially where here, there was no question that “the applicant expressly and unambiguously state[ed] his intention to claim broadly.”
Here, the lower court had issued a summary judgment of non-infringement based on its narrow claim construction (construing B as B1). The CAFC reversed that holding, but suggested that invalidity under enablement is the correct avenue to pursue on remand:
[W]e hold only that the court’s validity analysis cannot be used as basis for adopting a narrow construction of the claims. Instead, any validity issues that the defendants have preserved and wish to press can be addressed on remand, as was done in the Liebel-Flarsheim case. See Liebel-Flarsheim Co. v. Medrad, Inc., 481 F.3d 1371 (Fed. Cir. 2007) (holding invalid claims that had been given a broad construction at the patentee’s behest in an earlier appeal).
This type of case may soon be history if new continuation rules are truly effected.