Rio Tinto Alcan Intl Ltd v. Century Aluminum Co

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: Rio Tinto Alcan International Limited, Rio Tinto Alcan Inc. (Canada), and Alcan Primary Products Company LLC (Delaware)
  • Defendant: Century Aluminum Company and related entities (Delaware)
  • Plaintiff’s Counsel: Morris, Nichols, Arsht & Tunnell LLP; Norton Rose Fulbright US LLP
• Case Identification: 1:19-cv-00829, D. Del., 08/15/2019
• Venue Allegations: Venue is alleged to be proper on the basis that Defendants reside in the District of Delaware.
• Core Dispute: Plaintiff alleges that Defendant’s aluminum alloy products, sold for use in heat exchangers, infringe patents related to specific alloy compositions and manufacturing treatments designed to improve corrosion resistance and extrudability.
• Technical Context: The technology concerns specialized aluminum-manganese alloys used in demanding applications such as automotive and industrial HVAC/R systems, where a balance of material properties is critical for performance and manufacturing efficiency.
• Key Procedural History: The complaint alleges that in 2018, Defendant filed an objection with the U.S. Department of Commerce’s Bureau of Industry and Security (BIS), claiming it produces the specific alloy ("Alloy 31104") for which Plaintiff sought a tariff exclusion. Plaintiff relies on Defendant's statements in that BIS proceeding as evidence of infringement. The complaint also notes a prior intellectual property licensing agreement between the parties that expressly excluded the patents-in-suit, which may be relevant to allegations of knowledge and intent.

Case Timeline

Date	Event
2002-12-23	’071 Patent Priority Date
2008-06-10	’748 Patent Priority Date
2010-08-24	’071 Patent Issue Date
2011-09-27	’748 Patent Issue Date
2013-06-01	Alleged date of Defendant's knowledge of patents (approx.)
2018-08-01	Plaintiff applies to BIS for tariff exclusion (approx.)
2018-09-01	Defendant files objection with BIS (approx.)
2018-10-01	Plaintiff files rebuttal with BIS (approx.)
2018-11-01	Defendant files sur-rebuttal with BIS (approx.)
2019-08-15	First Amended Complaint Filing Date

II. Technology and Patent(s)-in-Suit Analysis

U.S. Patent No. 8,025,748 - "Al-Mn based aluminum alloy composition combined with a homogenization treatment" (Issued Sep. 27, 2011)

The Invention Explained

• Problem Addressed: The patent describes a trade-off in prior art aluminum alloys used for heat exchanger tubing: alloys with superior corrosion resistance (like AA 3012A) were difficult and costly to manufacture due to poor extrudability. Additionally, these alloys were prone to forming coarse grains during the high-temperature brazing process, which could be "detrimental to corrosion resistance" (’748 Patent, col. 1:43-51).
• The Patented Solution: The invention claims a specific aluminum-manganese (Al-Mn) alloy composition combined with a particular heat treatment process called homogenization, performed within a temperature range of 550°C to 600°C (’748 Patent, col. 2:5-9). This specific combination of composition and treatment is described as creating a microstructure with sufficient manganese out of solution to improve extrudability, while also forming manganese-rich dispersoid particles that inhibit the undesirable coarse grain formation during subsequent brazing (’748 Patent, col. 3:25-37).
• Technical Importance: The claimed invention provides a method to produce aluminum alloy billets that combine high extrudability with a uniform, fine-grain surface structure after brazing, aiming to improve both manufacturing efficiency and the final product's corrosion resistance (’748 Patent, col. 3:20-23).

Key Claims at a Glance

• The complaint asserts infringement of at least independent claim 1 (Compl. ¶41).
• Claim 1 Essential Elements:
  • An aluminum alloy heat exchanger extruded tube.
  • Comprising an aluminum alloy composition "consisting essentially of" specific weight percentages of manganese, iron, silicon, titanium, copper, nickel, and magnesium.
  • The aluminum alloy is cast as an ingot.
  • The ingot is "homogenized at a homogenization temperature ranging between 550 and 600° C."
  • The homogenized ingot is then extruded into tubes.

U.S. Patent No. 7,781,071 - "Aluminum alloy tube and fin assembly for heat exchangers having improved corrosion resistance after brazing" (Issued Aug. 24, 2010)

The Invention Explained

• Problem Addressed: In a typical brazed aluminum heat exchanger, it is desirable for the fins to corrode before the tubes, thereby sacrificially protecting the tubes from perforation. The patent notes that a common method to achieve this, applying a zinc coating to the tubes, had a significant drawback: during brazing, the zinc would melt and enrich the joints between the tube and fin, causing these critical joints to become the first point of corrosive failure (’071 Patent, col. 2:1-6).
• The Patented Solution: The invention is not a single alloy, but a complete "brazed heat exchanger assembly" comprising tubes and fins made from two distinct, galvanically compatible aluminum alloys (’071 Patent, Abstract). The key is the relationship between the manganese (Mn) content in the tube alloy (the "first aluminum alloy") and the fin alloy (the "second aluminum alloy"). By controlling the compositions according to a specific formula—"Mntube(wt %)>Mnfin(wt %)–0.8 wt %"—the fin is designed to be "galvanically sacrificial" to the tube without any need for zinc coatings (’071 Patent, col. 8:19-27).
• Technical Importance: This alloy pairing allows for the creation of a durable heat exchanger where corrosion proceeds in a controlled, predictable manner (fins first), enhancing product lifetime while avoiding the manufacturing complexities and potential failure modes associated with zinc coatings (’071 Patent, col. 3:41-52).

Key Claims at a Glance

• The complaint asserts infringement of at least independent claim 1 (Compl. ¶46).
• Claim 1 Essential Elements:
  • A brazed heat exchanger assembly comprising extruded heat exchanger tubes joined to heat exchanger fins.
  • The tubes are formed of a "first aluminum alloy" with a specific composition (ranges for Mn, Cu, Zn, Fe, Si, Ni, Ti).
  • The fins are formed of a "second aluminum alloy" with a different specific composition (ranges for Mn and Zn).
  • The assembly exhibits functional properties: the tubes have "good self corrosion protection" and the fins are "galvanically sacrificial relative to the heat exchanger tubes."
  • The manganese weight percentages of the first and second alloys are related by a specific mathematical formula.

III. The Accused Instrumentality

Product Identification

• The accused products are identified as "Century Alloy Products," including ingot, billet, and slab products, and are specifically referred to as "extrusion billet alloy '31104'" (Compl. ¶¶24-25).

Functionality and Market Context

• The complaint alleges these products are aluminum alloys with a specific chemical composition sold as raw material to customers, who then extrude them into tubes for heat exchangers (Compl. ¶31). The products are alleged to have "particular properties, such as good self-corrosion protection and galvanic compatibility" that make them suitable for "niche industrial air conditioning markets" where high performance is required (Compl. ¶33). The primary evidence for the products' composition and intended use is drawn from Defendant's public filings with the BIS, in which Defendant allegedly claimed to manufacture this specific alloy (Compl. ¶¶25, 27). The complaint contains a claim chart comparing the limitations of claim 1 of the '748 patent to the alleged properties of the Century Alloy Products (Compl. pp. 7-8).

IV. Analysis of Infringement Allegations

'748 Patent Infringement Allegations

Claim Element (from Independent Claim 1)	Alleged Infringing Functionality	Complaint Citation	Patent Citation
an aluminum alloy composition consisting essentially of, in weight percent, between 0.90 and 1.30 manganese...	The chemical composition of the accused product includes between 0.90% and 1.10% manganese and meets the other specified elemental ranges.	¶29	col. 9:10-14
the aluminum alloy being cast as an ingot...	Century casts the aluminum alloy as an ingot.	¶29	col. 9:14-15
...and homogenized at a homogenization temperature ranging between 550 and 600° C.	On information and belief, Century uses a homogenization cycle of 4hrs/580°C.	¶29	col. 9:15-17
...before extruding the homogenized ingot into tubes.	Century sells the homogenized ingot to customers who specialize in extruding heat exchanger tubes.	¶31	col. 9:17-18

• Identified Points of Contention:
  • Scope Questions: Claim 1 is directed to "extruded tubes," whereas Defendant is alleged to sell the precursor "ingot" or "billet." This raises the question of whether Defendant can be liable for direct infringement, or if liability depends entirely on proving indirect infringement (inducement or contributory infringement) based on the actions of its customers who perform the final extrusion step.
  • Technical Questions: The complaint's allegation for the homogenization temperature and duration (4hrs/580°C) is made "on information and belief." A central evidentiary question will be whether discovery confirms that Defendant's actual manufacturing process meets this claimed process limitation. Further, the use of the term "consisting essentially of" may create a dispute over whether any unlisted trace elements in the Century Alloy Products materially alter the alloy's claimed properties.

'071 Patent Infringement Allegations

The complaint provides a claim chart alleging how the Century Alloy Products meet the limitations for the "first aluminum alloy" used for the tubes (Compl. p. 10).

Claim Element (from Independent Claim 1)	Alleged Infringing Functionality	Complaint Citation	Patent Citation
A brazed heat exchanger assembly comprising extruded heat exchanger tubes joined to heat exchanger fins...	On information and belief, Defendant's customers create such assemblies by joining tubes made from Century Alloy Products to heat exchanger fins.	¶35	col. 8:1-2
...said heat exchanger tubes are formed of a first aluminum alloy comprising 0.4 to 1.1% percent by weight manganese...	The chemical composition of the Century Alloy Products allegedly meets the specified elemental ranges for the first aluminum alloy, including 0.90% to 1.10% manganese.	¶35	col. 8:3-11
...said heat exchanger fins are formed of a second aluminum alloy comprising 0.9 to 1.5% by weight manganese and at least 0.5% by weight zinc...	On information and belief, Defendant's customers form fins from a second alloy meeting these specifications.	¶35	col. 8:12-15
...wherein the manganese weight percent of the first aluminum alloy is related to the manganese weight percent of the second aluminum alloy by the formula...	On information and belief, Defendant's customers use a second alloy such that the manganese relationship satisfies the recited formula.	¶35	col. 8:19-27

• Identified Points of Contention:
  • Scope Questions: The claim is directed to a two-component "assembly." Since Defendant is only alleged to supply the material for one component (the tubes), infringement liability appears to rest entirely on a theory of contributory infringement.
  • Technical Questions: The complaint's allegations regarding the composition of the "second aluminum alloy" (the fins), the final assembly structure, and the functional relationship between the components (i.e., that the fins are "galvanically sacrificial") are all made "on information and belief." A primary question for the case is what evidence Plaintiff can develop to show that Defendant's customers actually combine the accused alloy with fins that meet the specific claim limitations to create a fully infringing final product.

V. Key Claim Terms for Construction

• The Term: "consisting essentially of" (’748 Patent, Claim 1)

  • Context and Importance: This term defines the chemical composition of the alloy. Its construction is critical because it determines whether the presence of unlisted elements in Defendant's product would avoid infringement. Practitioners may focus on this term to dispute whether trace impurities or other unlisted additives in the Century alloy materially alter the basic and novel properties of the invention—namely, the balance of extrudability and post-brazing grain structure.
  • Intrinsic Evidence for Interpretation:
    • Evidence for a Broader Interpretation: The term is a legal term of art generally understood to permit the presence of unlisted ingredients so long as they do not materially affect the invention's fundamental characteristics.
    • Evidence for a Narrower Interpretation: The detailed description emphasizes the importance of keeping certain elements like copper, iron, and magnesium at very low levels to achieve the desired corrosion resistance and brazeability (’748 Patent, col. 4:38-44). A party could argue that this focus on purity implies that even small amounts of certain unlisted elements could be material.

• The Term: "galvanically sacrificial relative to the heat exchanger tubes" (’071 Patent, Claim 1)

  • Context and Importance: This functional language is the core of the ’071 invention, defining the electrochemical relationship between the fin and the tube. The entire infringement case for this patent depends on proving that the final assemblies made with Defendant's alloy exhibit this property.
  • Intrinsic Evidence for Interpretation:
    • Evidence for a Broader Interpretation: The plain meaning suggests simply that the fin corrodes preferentially over the tube in a galvanic couple.
    • Evidence for a Narrower Interpretation: The specification provides specific, quantitative context for this term. It describes measuring galvanic corrosion current via ASTM G71-81 and states the current "must preferably exceed +0.05 microamps per square centimeter" from fin to tube (’071 Patent, col. 4:46-51). Parties may argue that this passage defines the specific technical standard an accused product must meet to be considered "galvanically sacrificial."

VI. Other Allegations

• Indirect Infringement: The complaint heavily relies on theories of indirect infringement for both patents. It alleges contributory infringement by asserting the Century Alloy Products are a material part of the inventions, are especially adapted for an infringing use, and have no substantial noninfringing uses due to their specialized properties and high cost (Compl. ¶¶33, 38). It also alleges inducement based on Defendant's alleged knowledge that its customers use the alloy to make infringing tubes and assemblies (Compl. ¶¶34, 39, 42, 46).
• Willful Infringement: The complaint alleges Defendant has had knowledge of the Asserted Patents "since at least June 2013" (Compl. ¶22). Further, it is alleged that Defendant was put on notice of the patents during a prior licensing negotiation, in which the Asserted Patents were expressly excluded from the license granted to Defendant (Compl. ¶26). This history, combined with Defendant’s subsequent actions detailed in the BIS proceedings, is presented to support a claim for willful infringement and enhanced damages (Compl., Prayer for Relief ¶b).

VII. Analyst’s Conclusion: Key Questions for the Case

• A core issue will be one of evidentiary development: The complaint's infringement allegations are founded on Defendant's public statements to a government agency. A key question is whether discovery will confirm that the alloy Defendant actually manufactures and sells conforms to those public statements and, crucially, meets the claim limitations currently pled only "on information and belief," such as the specific homogenization process ('748 patent) and the existence of a fully infringing two-part assembly ('071 patent).
• The case will also turn on questions of indirect liability: As Defendant is alleged to supply only a material component of the claimed inventions, Plaintiff's success depends on proving the elements of contributory and/or induced infringement. This will require demonstrating not only that Defendant's customers' activities constitute direct infringement, but also that Defendant possessed the requisite knowledge and specific intent for its alloy to be used in an infringing manner.
• A third central issue may be one of definitional scope: For the '748 patent, the dispute could focus on the term "consisting essentially of." The outcome may depend on whether the precise chemical makeup of the Century Alloy Products includes any unlisted elements that can be shown to materially alter the claimed invention's "basic and novel properties" related to extrudability and grain structure.