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Mangosoft v. Oracle

decided on May 14, 2008 by the Court of Appeals for the Federal Circuit

review by J. Matt Buchanan | published February 16, 2018 | updated February 16, 2018

tags: claim construction, dictionary, appellate procedure, drafting, summary of the invention, object of the invention, prosecution disclaimer, vitiation

In Mangosoft v. Oracle Corporation, the Court of Appeals for the Federal Circuit affirmed a summary judgment holding that Oracle did not infringe U.S. Patent No. 6,148,377 [text]. The appeal presented only a single issue—the construction of a single claim term. Mangosoft argued that the district court, which issued its summary judgment order before the Federal Circuit's Phillips decision, construed the term 'local' with an improper influence "by references by the parties to a technical dictionary." On appellate review, the Federal Circuit noted that "there is no question that dictionaries were considered," and then explained that Phillips does not preclude their use as long as the ultimate construction given the claims is grounded in the intrinsic evidence. Conducting its own de novo, Phillips-guided claim construction analysis, the Court determined that the district court's construction is "fully consistent with and supported by the intrinsic record—as well as the dictionary—and thus fully comports with our precedent." In its analysis, the Court noted an impact of the Summary of the Invention section of the patent, and a listed 'object of the invention.' Lastly, after noting that the prosecution history provides further support for the district court's claim construction, the Court rejected Mangosoft's argument for a broader construction on grounds that doing so would vitiate the term.

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claim construction | dictionary

Phillips doesn't preclude use of dictionaries, but requires that the ultimate construction given a claim term be grounded in the intrinsic evidence and not an abstract definition

The Court rejected an argument that the district court's claim construction was improper for being influenced by references to a technical dictionary, explaining that its decision in Phillips does not preclude the use of dictionaries, as long as they are kept in there proper place. The Court explained that reference to dictionaries:

"is not prohibited so long as the ultimate construction given to the claims in question is grounded in the intrinsic evidence and not based upon definitions considered in the abstract. (emphasis added)

Thus, use of a dictionary in a Phillips-guided claim construction analysis is acceptable, so long as the resulting claim construction is supported by the intrinsic record. Practically speaking, then, a dictionary may provide a starting point for an analysis, but any definition gleaned from the dictionary must ultimately be consistent with the intrinsic evidence of the patent, which includes the claims, specification, and the prosecution history. As explained by the Court:

"[W]hen considered in the context of and not divorced from the intrinsic evidence, there is nothing improper about referencing this [dictionary] definition in correctly construing the claim."

Ultimately, the court noted that the district court's claim construction was consistent with and supported by the intrinsic record and the dictionary. As such, the Court concluded, it "fully comports with our precedent."

appellate review | claim construction

On appellate review, the Federal Circuit reviews the result of a claim construction analysis and need not focus on the methodology used by the district court

After elabborating on the proper use of dictionaries in the claim construction process, the Court reminded us all that it "review[s] judgments, not opinions, and need not focus on the methodology used by the district court."

So, while Phillips provides a process and framework for performing a claim construction analysis, the Federal Circuit, still, of course, only reviews the result of that process and framework on appellate review.

claim construction

Court rejects claim construction that is inconsistent with the claims and specification

The Court rejected Appellant's offered construction of the claim term 'local' as being inconsistent with the claims and specification because it "would read 'local' to mean something beyond the breadth of anything in the claims or the specification."

The intrinsic record did not support the broad construction offered by Appellant. Indeed, the offered construction was so broad that, if adopted, would render the term “local” superfluous.

claim construction | summary of the invention | aspect of the invention | object of the invention | drafting

Summary of Invention discussing an aspect of the invention provides support for narrow claim construction

The Court pointed to the Summary of the Invention section of the patent as supporting the district court's claim construction. Appellant argued that the Summary was directed at only one "aspect" of the invention and, as such, shows that the narrow construction "relates solely to one embodiment."

The Court viewed this argument as of no consequence, explaining that the "aspect" of the invention discussed in the Summary " precisely the aspect of the invention at issue in claim 1."

The Court also looked to the disclosure of an "object of the invention" in the specification, and the consistent representation by the figures and description as being supportive of the district court's claim construction.

claim construction | prosecution disclaimer | vitiation

Prosecution disclaimer prohibits a claim construction that would vitiate a limitation added during prosecution

Reviewing the prosecution history as part of its Phillips-guided claim construction, the Court observed that Appellant had amended claim 1 to include the term 'local' and that adopting the construction it now offered would be inconsistent with both the cancelled claim from where the limitation to claim 1 was derived and the definition found in the specification. Adopting the Appellant's offered claim construction would read the added limitation out of the claim. The doctrine of prosecution disclaimer prohibits this type of recapture.