Afg Industries, Inc. And Asahi Glass Company, Ltd. v. Cardinal Ig Company, Inc., and Andersen Windows, Inc.
Docket: 03-1078
Court: Court of Appeals for the Federal Circuit; July 13, 2004; Federal Appellate Court
AFG Industries, Inc. and Asahi Glass Company, Ltd. (plaintiffs-appellants) appealed a summary judgment decision from the United States District Court for the Eastern District of Tennessee, which ruled that Cardinal IG Company, Inc. (defendant-appellee) did not infringe U.S. Patent No. 4,859,532, related to a glass window with a coating designed to reflect infrared light and reduce heat transfer. The Federal Circuit found that the district court erred in its noninfringement ruling and therefore vacated and remanded the case.
The litigation began in 1996, focusing on the '532 patent, which describes a transparent laminated product with a specific five-layer coating structure, including alternating layers of zinc oxide (ZnO) and silver (Ag), with defined thicknesses. Cardinal's LoE2 glass products utilize a magnetron sputter deposition method to create these layers, allowing for controlled deposition environments. The court emphasized that the patent's claim is a product claim, meaning it covers the inventive glass structure regardless of the manufacturing process used.
A key issue in the appeal concerns whether multiple sequential applications of a single material constitute a single layer or multiple layers, particularly in the context of Cardinal's products, which contain a zinc oxide layer produced through at least three separate depositions. Additionally, the appeal addresses whether certain titanium dioxide (TiO2) depositions in Cardinal's products meet the necessary thickness to qualify as a layer.
Approximately one year after AFG filed a lawsuit, Cardinal sought summary judgment for noninfringement, while AFG countered with a cross-motion for summary judgment of literal infringement. Following a Markman hearing, the district court ruled in favor of Cardinal by granting summary judgment of noninfringement and dismissing the case. AFG appealed, leading to a vacating of the summary judgment and a remand for further proceedings, with the appellate court emphasizing the need for precise claim term definitions, particularly "layer." On remand, the district court defined the claim terms and again granted summary judgment favoring Cardinal, prompting another appeal from AFG, which argued errors in the term constructions, including "layer."
The appellate court defined "layer" as "a thickness of material of substantially uniform chemical composition, but excluding interlayers having a thickness not to substantially affect the optical properties of the coating." It based this interpretation on the claim language, written description, and the implications of the prior Goodman patent, rejecting Cardinal's proposal that "layer" must be bounded by a different chemical composition to avoid anticipation issues. The court did not resolve whether multiple sequential applications of a chemical compound constitute a single "layer," deferring that determination to the trial court.
On remand, the district court reevaluated the claim construction and again found that Cardinal did not infringe the '532 patent, defining "layer" by its formation method. As the accused products involved multiple sequentially deposited layers of zinc oxide, infringement was ruled out. The court also identified that some products contained titanium dioxide, further negating infringement claims. Lastly, while not appealed, the district court concluded that the Goodman patent did not anticipate the '532 patent. The appellate court noted that it reviews summary judgment grants without deference, affirming that such judgments are appropriate only when no genuine issues of material fact exist.
On summary judgment, evidence is examined favorably for the opposing party, resolving doubts in their favor. Infringement analysis involves two steps: first, the court interprets the scope and meaning of the asserted claim, then compares it to the accused product. The court reviews the first step without deference and assesses the second step for genuine material disputes that could prevent summary judgment. A trial court cannot conclusively determine noninfringement if conflicting evidence exists.
AFG challenges the district court's findings regarding the zinc oxide and titanium dioxide in Cardinal's LoE2 products. The '532 patent's claim specifies a 5-layered transparent coating of alternating zinc oxide and silver layers. The term "layer" has been previously defined by the court, excluding interlayers that do not affect optical properties. The claim specifies no thickness limitations for zinc oxide layers, contrasting with silver layers, which require a specific thickness. This established interpretation is protected under the law of the case doctrine, which prevents revisiting resolved issues unless certain exceptions apply, none of which are present here.
Consequently, the court's remand allowed only for the factual application of the claim to Cardinal's products, specifically determining if sequential applications of a chemical compound without intervening layers constitute a single "layer." The remand did not seek further clarification of "layer," but rather instructed the trial court to apply the established interpretation to the accused products.
Cardinal's accused LoE2 products involve the successive deposition of 200 units of zinc oxide to achieve a thickness of 600 to 890, which Cardinal claims results in 3 to 4.5 layers of zinc oxide. Cardinal argues that this layering falls outside the scope of the '532 patent's claim, suggesting a new interpretation that improperly incorporates a process limitation into a product claim. Citing precedents, it is asserted that the term "layer" in the '532 patent should not be tied to a specific manufacturing method. The document emphasizes that the determination of whether a structure qualifies as a "layer" depends on its structural and optical properties, rather than the method of application. Thus, multiple depositions do not necessarily indicate multiple layers unless they alter the product's structure or optical characteristics.
The court found that the trial court wrongly considered the method of creation as definitive for the structure of the accused products, leading to the vacation of the summary judgment. There are genuine material facts regarding infringement, including internal Cardinal documentation suggesting the presence of five layers, which may imply the deposits form a single layer. Additionally, evidence from secondary ion mass spectroscopy indicates that the accused products have a single middle layer of zinc oxide, showing no interface between the successive depositions, thus suggesting a uniform chemical composition.
The court affirms that the claim construction does not necessitate the absence of an interface between successive depositions of the same material to define a "layer." Evidence suggests that successive depositions may constitute a single layer, raising genuine issues of material fact regarding the infringement of Cardinal's LoE2 products, especially in light of Cardinal’s internal documents indicating these products contain a single layer of zinc oxide. The five-layer transparent coating of the '532 patent does not include titanium dioxide layers between zinc oxide and silver layers. AFG contends that the district court wrongly deemed that Cardinal's LoE2 products contain a titanium dioxide layer that excludes them from the claim's scope, and it is noted that not all accused products feature a titanium dioxide thickness. The court vacates the district court's noninfringement judgment concerning titanium dioxide. On remand, the trial court will evaluate the accused products individually, particularly regarding their varying titanium dioxide thicknesses. AFG also contests the noninfringement finding for products containing titanium dioxide thicknesses of 35 or more, asserting that such thickness constitutes a "layer" affecting optical properties. Cardinal’s process typically results in titanium dioxide thickness ranging from 20 to 40, but the impact on optical properties remains uncertain. Genuine material fact issues preclude summary judgment on noninfringement of the '532 patent, prompting the court to vacate and remand the decision, with each party responsible for its own costs. The court does not indicate a need for refined claim construction in this case.
Circuit Judge Pauline Newman dissents from the panel's decision to remand a case for a third time regarding the claim construction of the term "layer." She asserts that claim construction is a legal matter subject to de novo review, and the case is ripe for a definitive decision rather than further remand. The case has undergone three Markman hearings and appeals, with the first two focused on titanium dioxide deposits, concluding that a "layer" is a material of uniform chemical composition. In the third hearing, the district court determined that Cardinal's multiple zinc oxide deposits constituted multiple layers. The current court's position appears to restrict the district court from evaluating whether multiple sputtering deposits create additional layers unless they influence structure and optical properties. Newman argues that the new technical context warrants consideration for correctness. Since the case was filed in 1996, extensive evidence has been presented, and the district court has consistently ruled no infringement on summary judgment. She emphasizes the need for finality in this relatively straightforward technical question, opposing her colleagues' remand for another Markman hearing.
