Edwards Lifesciences LLC v. Cook Inc. (Fed. Cir. Sept. 22, 2009)

In this case, the district court (Northern District of California) granted summary of no infringement.  The Federal Circuit, in an opinion by Judge Lourie, affirmed the underlying claim construction and also affirmed the finding of no infringement.  The Court's opinion, while lengthy, provides examples of how the Court may narrowly construe claim terms despite the existence of broadening amendments made during prosecution, definitions of non-claim terms found only in descriptions of preferred embodiments, and the doctrine of claim differentiation.

The patents at issue relate to intraluminal grafts for treating aneurisms and occlusive diseases of the blood vessels without open surgery.  As explained by the Federal Circuit, the patents (which share a common specification) describe "one method of treating an aneurism using two overlapping grafts, whereby the degree of overlap can be adjusted to change the overall length of the graft … [and also describe] a 'trouser graft,' which has a bifurcation at its downstream end, and a supplemental graft that overlaps with one of the legs of the trouser graft."

During claim construction, the district court had construed the claims terms "graft," "bifurcated base structure," and "bifurcated base graft structure" (1) to be intraluminal; (2) to require wires; (3) to require that those wires be malleable; and (4) to preclude any resilience from such malleable wires.  The defendants successfully argued on summary judgment that their devices could not infringe as the devices did not have malleable wires, but instead had resilient, self-expanding wires.  The district court found that these self-expanding wires cannot be "malleable" as the specification states that "malleable" means they do not "expand[] by virtue of their own resilience."  The Federal Circuit affirmed on each of the four points above, which will be briefly discussed in turn.

1. The Claimed Devices Must Be Intraluminal

Plaintiff argued that, given the language in the claims, the specification, and the prosecution history, an "intraluminal graft" is something different than a "graft."  However, the Federal Circuit pointed out that "the specification consistently uses the words 'graft' and 'intraluminal' interchangeably … akin to a definition equating the two."  Also, "the specification frequently describes an 'intraluminal graft' as 'the present invention' or 'this invention,' indicating an intent to limit the invention to intraluminal devices."  Further, while certain claims used the term "intraluminal graft" and others used the unmodified term "graft," the Federal Circuit found that "the doctrine of claim differentiation does not require us to give the 'graft' devices their broadest possible meaning.  We may instead limit 'grafts' to 'intraluminal' devices, as demanded by the specification."  Finally, while during prosecution the inventors amended an independent claim to delete the modifier "intraluminal" from the term "graft", the remarks accompanying the amendment stated that the amended claim "defines an intraluminal graft", which the Federal Circuit found not to affect the breadth of the claim.

2. Intraluminal Devices Must Have Wires

Plaintiff argued that not all intraluminal devices require wires and certain claims of the patents require wires while others do not.  However, the Federal Circuit noted that "the parties agreed at trial that intraluminal devices require wires."  Also, "every embodiment described in the specification and shown in the drawings includes wires."  Further, every claim at issue requires that the two graft devices be "anchored," "attached," "attachable," or "dockable" to each other, and the parties agreed before the district court that "only wires perform that function."  Finally, while plaintiff argued claim differentiation based on the fact that certain claims add wire limitations, the Federal Circuit held that "claim differentiation is a rule of thumb that does not trump the clear import of the specification."

3. The Wires in Intraluminal Devices Must Be Malleable

Plaintiff argued that, if wires we required by the claims, such wires need not be malleable due to the fact that the term "malleable" does not appear in any of the claims, the doctrine of claim differentiation, statements in the specification, and amendments made to the claims during prosecution.  However, the Federal Circuit found that the inventors "disparages prior art resilient wires in their 'background art' section of the specification" while "[t]he specification then describes the wires of the invention as malleable and states that the device is expanded by use balloons."  Also, while one of the patent claims did explicitly require a "resilient reinforcement wire", this particular wire was found in the "skirt portion of the graft" and therefore "all the rest of the graft is made of malleable wire."  Finally, while during prosecution "the inventors canceled claims requiring 'malleable wires' and replaces them with claims requiring only 'wires,' they conducted the prosecution as if the wires were required to be malleable."

4. Malleable Wires and Resilient Wires Are Mutually Exclusive

Plaintiff argued that malleable wires may still display some resilience and while the inventors apparently defined the term "malleable" in the specification, this definition appeared in the description of a preferred embodiment, not the invention as a whole, so the district court erred by rejecting the plain meaning of the term "malleable."  The Federal Circuit found that the "specification defines 'malleable' to exclude any substantial resilience, and that definition overrides any ordinary meaning of the word 'malleable' that might allow for substantial resilience."  The Court also found that "the location within the specification in which the definition appears is irrelevant … [and] the specification's use of 'i.e.' [in the alleged definition] signals an intent to define the word to which it refers, 'malleable,' and that definition was not limited to the embodiment being discussed."

While the term "malleable" was not in the patent claims and the Court noted that it does "not ordinarily construe words that are not in claims," it pointed out that the district court used the term "malleable" in its initial constructions.  The parties then debated the definition of this term before the district court, so the district court went back to the patent specification to further define "malleable."  The Federal Circuit found the district court was "correct to look to the specification to clarify its initial construction."

Ultimately, the Federal Circuit affirmed the district court's claim construction and finding of no infringement.

If you have a comment or would like to see a particular topic discussed on this site, please e-mail grayonclaims@gmail.com.