0:22-cv-00476
Cortec Corp v. Verpa Folie Weidhausen GmbH
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: Cortec Corporation (Minnesota)
- Defendant: Corpac GmbH & Co. KG (Germany)
- Plaintiff’s Counsel: Taft Stettinius & Hollister LLP
- Case Identification: 0:22-cv-00476, D. Minn., 02/13/2023
- Venue Allegations: Venue is asserted based on 28 U.S.C. § 1391 and a contractual agreement between the parties.
- Core Dispute: Plaintiff alleges that its former German distributor breached their distribution agreement and engaged in trademark infringement, false designation of origin, and unfair competition by forming a new entity with competitors and selling unauthorized corrosion inhibiting film products.
- Technical Context: The dispute centers on vapor phase corrosion inhibitor (VCI) technology, where chemical compounds are integrated into packaging films to release a protective vapor that prevents corrosion on packaged metal goods.
- Key Procedural History: The complaint alleges that the dispute arises from a Distribution Agreement dated May 12, 2004. Around June 2018, Defendant Corpac allegedly entered into a formal relationship or "merger" with two direct competitors, Verpa and Safe-Pack, which Plaintiff characterizes as an unauthorized assignment and delegation of the agreement, leading to the sale of competing and unauthorized products. Plaintiff also alleges it repeatedly notified Defendant of these violations prior to filing suit.
Case Timeline
| Date | Event |
|---|---|
| 1999-05-28 | Earliest Priority Date for U.S. Patent No. 6,420,470 |
| 2002-07-16 | Issue Date for U.S. Patent No. 6,420,470 |
| 2004-05-12 | Cortec and Defendant's predecessor enter into Distribution Agreement |
| 2016-03-28 | Earliest Priority Date for U.S. Patent No. 10,697,070 |
| 2018-06-01 | Alleged "merger" of Defendant with Verpa and Safe-Pack |
| 2020-06-30 | Issue Date for U.S. Patent No. 10,697,070 |
| 2023-02-13 | First Amended Complaint Filing Date |
II. Technology and Patent(s)-in-Suit Analysis
Although the First Amended Complaint pleads counts for trademark infringement and breach of contract rather than patent infringement, it references Plaintiff’s patent portfolio (Compl. ¶15) and involves competing corrosion control technology. This analysis examines two representative Cortec patents in the context of the complaint's factual allegations.
U.S. Patent No. 10,697,070 - Corrosion inhibiting films
- Patent Identification: U.S. Patent No. 10,697,070 B1, “Corrosion inhibiting films,” issued June 30, 2020.
The Invention Explained
- Problem Addressed: The patent describes a need for effective vapor corrosion inhibitor (VCI) films that do not rely on nitrite salts, which have faced increased environmental and safety scrutiny (’070 Patent, col. 2:44-50). Additionally, many potential VCI materials are not sufficiently thermostable for use in the high-temperature melt-blending processes used to create plastic films (’070 Patent, col. 2:57-65).
- The Patented Solution: The invention is a nitrite-free packaging film that incorporates a specific VCI film additive into a polymeric resin (’070 Patent, Abstract). This additive comprises both a volatile component (an ammonium or alkylammonium carboxylate and a triazole derivative) and a non-volatile component (such as amorphous silica or calcium carbonate) in a specific ratio, designed to be effective and stable during manufacturing (’070 Patent, col. 7:8-25). The patent also describes arranging these materials in multi-layer films to enhance performance (’070 Patent, col. 2:7-11).
- Technical Importance: This technology offers a method for producing VCI films that are effective at protecting metals while avoiding the use of traditional, but increasingly regulated, nitrite-based chemistries (’070 Patent, col. 2:44-50).
Key Claims at a Glance
- Independent claim 1 is asserted as representative.
- The essential elements of claim 1 are:
- A film for inhibiting corrosion, comprising:
- a polymeric resin; and
- a VCI film additive (between 1-10% by weight of the film) comprising a volatile corrosion inhibiting component and an additional non-volatile ingredient;
- the volatile component comprises an ammonium or alkylammonium carboxylate and a triazole derivative;
- the non-volatile component comprises amorphous silica, calcium carbonate, wax, a salt of stearic acid, or a combination thereof;
- the weight ratio of the non-volatile component to the volatile component is between 0.5 and 6.0.
- The complaint does not specify which claims may be asserted.
U.S. Patent No. 6,420,470 - Flame retardant films
- Patent Identification: U.S. Patent No. 6,420,470 B1, “Flame retardant films,” issued July 16, 2002.
The Invention Explained
- Problem Addressed: The patent addresses the challenge of creating a single packaging film that is both flame retardant and provides corrosion protection (’470 Patent, col. 2:1-4). The chemicals used for flame retardancy (FR) and the chemicals used for VCI protection are described as typically being "mutually antagonistic," meaning they can react with and negate each other's effectiveness, particularly during the high-heat extrusion process (’470 Patent, col. 2:55-59).
- The Patented Solution: The invention is a plastic film that combines a specific, compatible blend of FR and VCI components (’470 Patent, Abstract). The solution involves using a particular FR system (a mixture of an antimony oxide and a bromoaryl compound) blended with selected VCI compounds (amine and ammonium salts) in a polyethylene resin (’470 Patent, col. 1:57-67). The patent further discloses using multi-layer laminates to physically separate high concentrations of FR chemicals on outer layers from VCI chemicals on inner layers (’470 Patent, col. 2:26-30).
- Technical Importance: This innovation enables the production of advanced packaging materials for applications, such as military equipment storage, that require simultaneous compliance with fire safety standards and long-term corrosion prevention for metal assets (’470 Patent, col. 2:5-11).
Key Claims at a Glance
- Independent claim 1 is asserted as representative.
- The essential elements of claim 1 are:
- A plastic resin film for protecting metallic articles, impregnated with a blend of an FR component and a VCI component.
- The FR component is a mixture of an antimony oxide and a specific bromoaryl compound within a defined molar ratio.
- The film consists of a blend of 8-12% FR component, 0.5-1.5% VCI component, and the balance polyethylene resin.
- The VCI component is selected from amine and ammonium salts.
- The components are combined with polyethylene to form a film modifier mixture.
- The complaint does not specify which claims may be asserted.
III. The Accused Instrumentality
Product Identification
The complaint identifies Defendant's "unauthorized VCI products," including a specific product named "Corpalin® COEX (coextruded) film" (Compl. ¶¶ 39, 44).
Functionality and Market Context
- The complaint alleges that the Corpalin® film is a three-layer coextruded film designed for corrosion protection (Compl. ¶44). A diagram from Defendant’s website depicts the accused "Corpalin® COEX (coextruded) film" as a three-layer structure with specific VCI-related functions assigned to each layer (Compl. ¶44). This diagram describes the layers as a "Barriere Schicht" (Barrier layer), a "Sperrschicht" (Blocking layer), and a "VpCI Trägerschicht" (VCI carrier layer), and claims that the VCI agent vaporizes only to the inside (Compl. ¶44).
- The complaint alleges these products are sold in direct competition with Plaintiff and its authorized distributors, including to major automotive customers (Compl. ¶¶ 38, 40-41). It also alleges Defendant falsely represented that "we invented the Corpalin® COEX (coextruded) film" (Compl. ¶44).
IV. Analysis of Infringement Allegations
The complaint accuses Defendant of manufacturing and selling a competing "Corpalin® COEX (coextruded) film" (Compl. ¶44). The following table maps the elements of claim 1 of the ’070 Patent to the functionalities of this film as described in the complaint.
’070 Patent Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| a polymeric resin | The accused product is described as a "film" and a "coextruded film," which is made from a polymeric base resin. | ¶44 | col. 2:36-37 |
| a vapor corrosion inhibitor (VCI) film additive | The accused product is explicitly described as a VCI film, with a "VCI carrier layer" and "VCI molecules." | ¶44 | col. 2:40-43 |
| wherein the volatile corrosion inhibiting component comprises an ammonium or alkylammonium carboxylate... and a triazole derivative | The complaint does not provide any detail regarding the specific chemical composition of the VCI used in the accused Corpalin® film. | ¶¶ 41, 44 | col. 7:14-18 |
| wherein the additional ingredient comprises a non-volatile component... amorphous silica, calcium carbonate, wax, a salt of stearic acid, or a combination thereof | The complaint does not provide any detail regarding non-volatile components in the accused film's VCI additive. | ¶44 | col. 7:19-22 |
| and wherein the ratio of the non-volatile component to the volatile corrosion inhibiting component, by weight, is in a range of between about 0.5 and about 6.0 | The complaint does not provide information on the components or their ratios within the accused film's VCI additive. | ¶44 | col. 7:23-25 |
- Identified Points of Contention:
- Technical Questions: The primary question for a potential patent infringement claim is evidentiary. The complaint alleges the sale of a competing VCI film but is silent on its composition. A court would need to answer: What is the precise chemical formulation of the VCI additive in the accused Corpalin® film and other unauthorized VCI products? Does discovery show that it contains both an ammonium/alkylammonium carboxylate and a triazole derivative, as well as the claimed non-volatile components in the required ratio?
- Scope Questions: The complaint's description of the accused product as a multi-layer film raises questions related to claim scope and infringement under the doctrine of equivalents. While independent claim 1 of the ’070 patent is not limited to a multi-layer structure, the patent heavily teaches the benefits of such structures. An issue may be whether the specific three-layer design of the accused film (Compl. ¶44) practices the teachings of the patent in a way that infringes, even if it does not literally meet every limitation of a dependent claim.
V. Key Claim Terms for Construction
The Term: "triazole derivative" (’070 Patent, Claim 1)
Context and Importance: This term defines a required class of chemical compounds in the volatile VCI component. A finding of infringement hinges on whether the accused product contains a substance that falls within the court's construction of this term. Practitioners may focus on this term because the presence or absence of this specific chemical family is a dispositive technical fact.
Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The specification provides examples, stating "triazole compounds (such as benzotriazole or tolyltriazole)" (’070 Patent, col. 3:13-15). A party could argue the use of "such as" indicates that these are merely examples and the term should cover a wider class of related triazole-based chemicals known to those skilled in the art.
- Evidence for a Narrower Interpretation: Dependent claim 4 explicitly recites that "the triazole derivative is benzotriazole, tolyltriazole, or a combination thereof" (’070 Patent, col. 7:36-38). A party could argue this specific definition in a dependent claim suggests that the broader term in the independent claim should be interpreted narrowly, or that these are the only derivatives contemplated by the inventors.
The Term: "VCI film additive" (’070 Patent, Claim 1)
Context and Importance: The claim defines this "additive" as a multi-part system with specific components (volatile and non-volatile) and a required weight ratio between them. The construction will determine whether the entire VCI package in an accused product must be analyzed as a single "additive" to determine infringement.
Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The patent describes the additive in functional terms as the combination of ingredients that provides the VCI characteristics (’070 Patent, col. 3:6-10). A party may argue that as long as the claimed chemical types are present in the film in the correct overall ratio, they constitute the claimed "additive."
- Evidence for a Narrower Interpretation: The detailed description provides several highly specific formulations for the "VCI film additive" (e.g., "VCI film additive 410a") before they are blended into the final film product (’070 Patent, col. 8). A party could argue that the term implies a pre-formulated composition, and not just the coincidental presence of its constituent chemicals in the final film.
VI. Other Allegations
The complaint does not contain counts for patent infringement and therefore makes no direct allegations of indirect or willful patent infringement. However, the factual allegations made in support of the trademark and contract claims could be relevant if patent claims were added.
- Indirect Infringement: The complaint alleges that Defendant, through its merged entity, advertises and sells the accused Corpalin® film, including via a website that explains its layered structure and function (Compl. ¶44). These allegations could be used to build a case for induced infringement, by suggesting that Defendant's marketing materials and product data sheets instruct end-users on how to use the film in an infringing manner.
- Willful Infringement: The complaint alleges that Plaintiff "repeatedly notified Defendant Corpac of its violations" of the Agreement and that Defendant "failed to cease the complained of conduct" (Compl. ¶46). If these pre-suit notifications mentioned Cortec's broader intellectual property rights or the technological basis for the dispute, they could be used to argue that any subsequent patent infringement was willful.
VII. Analyst’s Conclusion: Key Questions for the Case
A threshold question is one of contract law: did Defendant’s 2018 merger and subsequent activities constitute a breach of the non-assignment, non-competition, or trademark provisions of the 2004 Distribution Agreement? The resolution of this issue may significantly influence the context of any intellectual property claims.
If patent claims are asserted, the central issue will be a technical and evidentiary question of chemical composition: does the accused "Corpalin®" film, or any other unauthorized VCI product sold by Defendant, contain the specific combination of an "ammonium or alkylammonium carboxylate" and a "triazole derivative" as required by claim 1 of the ’070 Patent? The case would likely turn on the results of chemical analysis of the accused products.
A key factual dispute tying together the contract, trademark, and potential patent claims is one of origin and inventorship: does the technology in the accused Corpalin® film originate from Defendant's own independent development, as its alleged claim of having "invented" the film suggests (Compl. ¶44), or is it derived from the technology and confidential information provided by Plaintiff under the prior distribution agreement?