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Justin E. Gray

IP Litigation Attorney at Foley & Lardner LLP

Former Adjunct Professor at Northwestern University School of Law

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Federal Circuit Panel Disagrees on Proper Role of Specification in Claim Construction

Arlington Industries, Inc. v. Bridgeport Fittings, Inc. (Fed. Cir. Jan. 20, 2011)

In this case, the Federal Circuit found that the district court misconstrued claim terms by importing a limitation from the specification into the claims, and vacated a grant of summary judgment.  Judge Lourie filed a dissent-in-part regarding the appropriate role of the specification in claim construction.

The patents at issue related to improved electrical connectors.  The district court construed the claim terms "spring metal adaptor" and "spring steel adaptor" from the patents as requiring a split in the adaptor.  Notably, the parties had already gone through claim construction of one of the patents-in-suit in an earlier case, and that district court did not find that the patent claims required a split adaptor.

On appeal, the Federal Circuit majority found that the district court erred by importing a "split" limitation into the claims.  The majority reasoned that only one of the four embodiments disclosed in the specification would support adding such a limitation, claim differentiation would weigh against adding the limitation, and the file history did not support such a limitation.  In addition, the majority explained that "This court has often acknowledged the fine line between reading a claim in light of the specification and importing a limitation from the specification into the claim.  Review of the intrinsic evidence reveals no intent to limit the term 'spring metal adaptor' by using it in a manner that excludes unsplit adaptors." (internal citations omitted).

In his dissent-in-part, Judge Lourie described claim construction as "[o]ne of the most difficult tasks in adjudicating patent cases."  Judge Lourie also provided the following commentary on claim construction:

But the basic mandate is for claims to be interpreted in light of the specification of which they are a part because the specification describes what the inventors invented.  The specification is the heart of the patent.  In colloquial terms, "you should get what you disclose."

The fine distinctions we often make concerning what is disclosed in a specification arise of course from how the inventors describe aspects of their invention.  They describe embodiments of the invention, preferred embodiments, specific examples, sometimes using language broader than expressed in the claims to describe embodiments, and finally, in frequent boilerplate, indicate that the invention isn't to be limited to what is expressly disclosed (as if they were unable to describe anything else they actually invented).  Questions then arise as to whether an invention is limited to a preferred embodiment, or to the disclosed embodiments, or to what the specification in some language indicates is part of the invention.

The problem in claim construction is thus our focus on our muddy, conflicting, and overly formulaic rules, [citing the KSR and Bilski Supreme Court decisions], when the real task of claim interpretation is to read the specification and determine what the inventors meant when they used the language they did.  Obviously the claims define the scope of protection accorded the owners of the patent.  But in construing the claims we should avail ourselves of the knowledge we glean from the patent specification to see what the inventors disclosed as their invention.  The bottom line of claim construction should be that the claims should not mean more than what the specification indicates, in one way or another, the inventors invented." (internal citations omitted)

The majority responded to Judge Lourie's dissent-in-part in a footnote, stating "The concurrence-in-part and dissent-in-part characterizes the specification as the 'heart of the patent' and, using 'colloquial terms,' states that 'you should get what you disclose.'  This devalues the importance of claim language in delimiting the scope of legal protection.  'Claims define and circumscribe, the written description discloses and teaches.'  Indeed, unclaimed disclosures are dedicated to the public."  (internal citations omitted).