By Jason Rantanen
Advanced Fiber Technologies (AFT) Trust v. J&L Fiber Services, Inc. (Fed. Cir. 2012) Download 11-1243
Panel: Lourie (author), Dyk (dissenting in part), Prost
This opinion provides guidance on the process of construing claim constructions and illustrates the continuing disagreement among the Federal Circuit judges about claim interpretation.
The technology at issue in this case involves screening devices used in the pulp and paper industry. Advanced Fiber Technologies (AFT) patented a screening device that purports to offer substantially increased efficiency and flow capacity. Two of the asserted independent claims include the term "screening medium"; the third contains the synonym "screening plate." The district court construed "screening medium" as "a perforated barrier through which stock is passed to remove oversized, troublesome, and unwanted particles from good fiber." Slip Op. at 8. It further interpreted a term from its construction, "perforated," as meaning "pierced or punctured with holes." Id. Based on this meaning of "perforated," the district court granted summary judgment of noninfringement as against the accused device, which used a "wedgewire" screen (a screen made by assembling closely spaced parallel wires). AFT appealed, challenging not the district court's construction of the term "perforated" but its construction of "screening medium."
Although not explicitly discussed by the opinion, construing claim constructions (which the majority refers to as "derivative construction" on page 14) raises some difficult issues above and beyond the challenges that come with construing the claim terms themselves - specifically, the degree of relationship between the claim term and the interpretation of the claim term's construction.
The majority opinion in Advanced Fiber provides some guidance in this area. First, the derivative construction "must follow the guiding principles set forth in Phillips." Slip Op. at 14. Second, whether "construing a claim term or a disputed term within a claim construction, our ultimate goal is determining the meaning and scope of the patent claims asserted to be infringed.'" Id., quoting Markman, 52 F.3d at 976.
Applying these two points, the majority agreed with AFT, concluding that the district court improperly relied on extrinsic evidence that contradicted the intrinsic evidence and that its own interpretation of "perforated" as simply "having holes or openings" was "fully consistent with the language of claim 1, "a screening medium having a plurality of openings therethrough," and claim 10. Slip Op. at 17.
Comment: The majority's approach to derivative constructions looks to be fairly useful, in that it suggests that derivative constructions should relate back to the meaning of the claim itself rather than going down the rabbit hole of attempting to independantly interpret interpretations. This approach thus adds to the methodology for construing constructions developed in Cordis Corporation v. Boston Scientific Corporation, 658 F.3d 1347 (Fed. Cir. 2011), another recent case dealing with an issue of derivative construction.
Writing in dissent, Judge Dyk would have affirmed the district court's construction. In Judge Dyk's view, the court should have read more into arguments the applicant made during prosecution and found that the applicant explicitly adopted the definition of "perforated plate" from a technical manual, the Handbook of Pulp & Paper Terminology, that the applicant cited during prosecution for the definition of "screen plate."
Note: Based on my reading of the opinion and the appellee's brief, neither the district court nor J&L appear to have relied on the Handbook's definition of "perforated plate."