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The Fine Line Between Reading a Claim in Light of the Specification and Importing a Limitation from the Specification into the Claim

January 20, 2011

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Last Month at the Federal Circuit - February 2011

Judges: Rader (author), Lourie (concurring-in-part and dissenting-in-part), Moore

[Appealed from: M.D. Pa., Judge Caputo]

In Arlington Industries, Inc. v. Bridgeport Fittings, Inc., No. 10-1025 (Fed. Cir. Jan. 20, 2011), the Federal Circuit vacated the district court’s grant of SJ of noninfringement of U.S. Patent Nos. 5,266,050 (“the ’050 patent”) and 6,521,831 (“the ’831 patent”), and remanded for further proceedings.

Arlington Industries, Inc. (“Arlington”) owns the ’050 and ’831 patents.  The ’050 patent discloses an improved electrical connector that can be snapped into an electrical junction box with one hand instead of two.  A “spring metal adaptor” or “spring steel adaptor” surrounds the leading end of the electrical connector and attaches the connector to the junction box.  The ’050 patent claims recite a “spring metal adaptor.”  The ’831 patent discloses a duplex electrical connector having two openings to allow the insertion of two electrical cables through the connector into a single hole in the junction box.  The ’831 patent claims recite “a spring steel adapter” secured to the cylindrical outbound end of the housing.

Arlington brought suit against Bridgeport Fittings, Inc. (“Bridgeport”) in two concomitant district court proceedings that produced different constructions of the same claim term from the ’050 patent.  In the earlier-filed case, the district court construed the term “spring metal adaptor” to mean “an adaptor made of spring metal,” finding the meaning clear in view of the claim language, specification, and prosecution history.  Arlington Indus., Inc. v. Bridgeport Fittings, Inc., No. 01-CV-0485, 2008 WL 542966 (M.D. Pa. Feb. 25, 2008) (“Arlington I”).  In the later-filed case, the district court construed the same claim term, however, to mean a “split spring metal adaptor,” finding that a necessary feature of the “spring” metal adaptor is that it is split.  Arlington Indus., Inc. v. Bridgeport Fittings, Inc., No. 06-CV-1105, 2007 WL 4276565 (M.D. Pa. Dec. 4, 2007) (“Arlington II”).  The Arlington II court found that a “split” allows the diameter of the adaptor to narrow upon insertion into the electrical junction box, and, without a split, it would not “spring.”  The Arlington II court similarly construed the term “spring steel adaptor” from the ’831 patent to require a split, applying the same analysis.  Bridgeport moved for SJ of noninfringement in light of the Arlington II construction.  The district court granted Bridgeport’s motions, and Arlington appealed.

On appeal, the Federal Circuit held that the Arlington II court erred in importing a “split” limitation into its constructions of “spring metal adaptor” and “spring steel adaptor.”  First, the Court found that the ordinary and customary meaning of “spring metal adaptor” in the ’050 patent was an adaptor made of spring metal.  The Court rejected Bridgeport’s arguments that the term “spring” modified the phrase “metal adaptor” such that the metal adaptor performs a “springing function.”  In so doing, the Federal Circuit noted that Bridgeport conceded before the district court that the adaptor is made from spring metal, thus indicating that the term “spring” described the type of metal rather than a particular function.

Second, the Federal Circuit rejected Bridgeport’s argument that the entire term “spring metal adaptor” should be defined by implication to require a split because the Court found that the specification did not show a clear intent to limit the claims to “split” embodiments.  In particular, only one of four embodiments was expressly described as having an “opening” that changes diameter to permit a spring action, and although the drawings consistently depicted an incomplete circle, the Court reiterated that drawings need not illustrate the full scope of the invention.

Importantly, the Court found that the ’050 patent claim language supported Arlington’s proposed construction.  Specifically, claim 1 recites a “spring metal adaptor being less than a complete circle,” while claim 8 omits the “less than a complete circle” modifier.  This difference indicated that, unlike the adaptor of claim 1, the spring metal adaptor of claim 8 can be either a complete or incomplete circle.  Similarly, a claim in a parent patent to the ’050 patent recites “a split circular spring metal adaptor,” while claim 8 of the ’050 patent omits the “split” modifier.  The Court concluded that reading a “split” or “incomplete circle” limitation into the term “spring metal adaptor” would render those additional modifiers superfluous.

Finally, the Court considered the prosecution history and Bridgeport’s expert testimony, and found that neither supported reading a “less than a complete circle” or “split” limitation into the terms “spring metal adaptor” or “spring steel adaptor.”  The Court acknowledged the “fine line between reading a claim in light of the specification and importing a limitation from the specification into the claim,” slip op. at 14, but found that the intrinsic evidence revealed no intent to limit the term “spring metal adaptor” to exclude unsplit adaptors.  Thus, the Court vacated the grant of SJ of noninfringement of the ’050 patent and remanded for further proceedings.

The Federal Circuit also held that the district court erroneously imported a “split” limitation into the “spring steel adapter” term from the ’831 patent.  In particular, the claim did not state that the adaptor is split, the specification did not define the spring steel adaptor as split, and nothing in the specification implicitly required a split adaptor.  The Court similarly rejected Bridgeport’s argument relying on the disclosure of embodiments showing a split adaptor in the specification, noting that the specification does not delimit the right to exclude; rather, that is the function and purpose of the claims.  Accordingly, the Court vacated the district court’s grant of SJ of noninfringement of the ’831 patent and remanded for further proceedings.

Judge Lourie concurred-in-part and dissented-in-part, agreeing with the majority in vacating the district court’s SJ decision regarding the ’831 patent, but disagreeing with the majority’s holding regarding the ’050 patent.  Specifically, Judge Lourie would construe the term “spring metal adaptor” in the ’050 patent to include the “split” limitation as construed by the Arlington II court because the figures and each disclosed embodiment showed the spring metal adaptor as less than a complete circle.  Ultimately, in Judge Lourie’s view, “[t]he specification is the heart of the patent.  In colloquial terms, ‘you should get what you disclose.’”  Lourie Dissent at 2.

In a footnote response, the majority pointed to the importance of the claim language in delimiting the scope of legal protection.  Quoting the late Judge Rich, the majority stated:  “[T]he name of the game is the claim.”  Slip op. at 15 n.2 (emphasis and citation omitted).


Summary authored by Jennifer R. Gupta, Esq.