DCT
0:13-cv-02980
HB Fuller Co v. Henkel Corp
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: H.B. Fuller Company (Minnesota)
- Defendant: Henkel Corporation (Delaware)
- Plaintiff’s Counsel: Faegre Baker Daniels LLP
- Case Identification: 0:13-cv-02980, D. Minn., 10/30/2013
- Venue Allegations: Venue is based on Defendant’s transaction of business in Minnesota, including directing products for sale, maintaining distributor relationships, and being registered to do business in the state.
- Core Dispute: Plaintiff alleges that Defendant’s Technomelt brand hot melt adhesives infringe a patent related to adhesive compositions that exhibit both high heat resistance and good cold temperature flexibility.
- Technical Context: The technology concerns the chemical formulation of hot melt adhesives, a widely used industrial product where performance across a broad range of temperatures is a critical and commercially valuable attribute.
- Key Procedural History: The complaint notes that Plaintiff provided Defendant with notice of infringement via letter on August 27, 2012. After the complaint was filed, the asserted patent was the subject of an Inter Partes Review (IPR2014-00606), which resulted in a certificate issued on February 9, 2018, cancelling claims 22-25, 27, and 28.
Case Timeline
| Date | Event |
|---|---|
| 1998-06-30 | '404 Patent Priority Date |
| 2004-12-21 | '404 Patent Issue Date |
| 2012-08-27 | Plaintiff provides Defendant with notice of alleged infringement |
| 2013-10-30 | Complaint Filing Date |
| 2018-02-09 | IPR Certificate issues, cancelling claims 22-25, 27, and 28 of '404 Patent |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 6,833,404 - "Hot Melts Utilizing a High Glass Transition Temperature Substantially Aliphatic Tackifying Resin," issued December 21, 2004
The Invention Explained
- Problem Addressed: The patent’s background section describes the "constant struggle" in the adhesives industry to simultaneously improve both the heat resistance and the cold temperature resistance of hot melt adhesives, as formulations that improve one property typically degrade the other (ʼ404 Patent, col. 2:38-48).
- The Patented Solution: The invention claims to solve this problem by using a specific type of tackifying resin in the adhesive composition: one that is "substantially aliphatic" and has a high glass transition temperature (Tg) of greater than 65°C. This specific component is described as enabling an adhesive that possesses both "surprisingly high heat resistance" and "good cold temperature flexibility" (ʼ404 Patent, Abstract; col. 4:1-6).
- Technical Importance: The invention sought to overcome a long-standing performance trade-off, enabling the creation of adhesives suitable for demanding applications such as goods shipped through both desert heat and winter cold (ʼ404 Patent, col. 2:41-48).
Key Claims at a Glance
- The complaint alleges infringement of "at least one claim" but does not identify any specific claims (Compl. ¶13). Independent claim 1 is the broadest composition claim.
- Independent Claim 1 recites the essential elements of a hot melt adhesive composition, including:
- About 10% to 50% by weight of a "substantially aliphatic tackifying resin" with a glass transition temperature (Tg) greater than 65°C.
- About 20% to 60% by weight of a thermoplastic base polymer.
- About 0% to 40% by weight of a wax.
- A further limitation that the concentration of the tackifying resin must be less than the concentration of the thermoplastic base polymer.
- The complaint does not explicitly reserve the right to assert dependent claims.
III. The Accused Instrumentality
Product Identification
- The complaint identifies "hot melt adhesives under the Technomelt brand name, including hot melt adhesives marketed as TS-106M and TS-106" (Compl. ¶12).
Functionality and Market Context
- The complaint describes the accused instrumentalities only as "hot melt adhesives" that Defendant "makes, markets, and sells" (Compl. ¶12). The complaint does not provide sufficient detail for analysis of the products' specific chemical composition, technical functionality, or market positioning.
IV. Analysis of Infringement Allegations
The complaint does not contain a claim chart or provide specific factual allegations mapping product features to claim elements. The following table summarizes the infringement theory for Claim 1 as implied by the complaint's general allegations.
- '404 Patent Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| A hot melt adhesive composition comprising: | The Technomelt TS-106M and TS-106 products are alleged to be hot melt adhesive compositions. | ¶12, ¶13 | col. 19:61 |
| a) about 10% by weight to about 50% by weight of at least one substantially aliphatic tackifying resin having a glass transition temperature of greater than 65° C.; | The accused products are alleged to contain a "substantially aliphatic tackifying resin" with a Tg greater than 65° C. within the claimed weight percentage range. | ¶13, ¶14 | col. 19:62-65 |
| b) about 20% by weight to about 60% by weight of at least one thermoplastic base polymer; and | The accused products are alleged to contain a thermoplastic base polymer within the claimed weight percentage range. | ¶13, ¶14 | col. 20:1-2 |
| c) 0% by weight to about 40% by weight of at least one wax; | The accused products are alleged to contain a wax, or no wax, within the claimed weight percentage range. | ¶13, ¶14 | col. 20:3-4 |
| wherein said tackifying resin concentration is less than said thermoplastic base polymer concentration. | The accused products are alleged to have a formulation where the concentration of the tackifying resin is less than the concentration of the thermoplastic polymer. | ¶13, ¶14 | col. 20:5-7 |
- Identified Points of Contention:
- Technical Questions: The primary dispute will likely be factual and evidentiary. A central question is: what is the actual chemical composition of the accused Technomelt products? Discovery will be required to determine if they contain the specific resin type (aliphatic, Tg > 65°C), polymer, and wax in the claimed weight percentages and relative concentrations. No probative visual evidence provided in complaint.
- Scope Questions: A potential dispute over claim scope may arise concerning the term "substantially aliphatic." The patent specification provides numerical guidelines (e.g., "less than about 10% by weight" of aromaticity), raising the question of whether this language limits the broader term (ʼ404 Patent, col. 5:8-12).
V. Key Claim Terms for Construction
The Term: "substantially aliphatic tackifying resin"
Context and Importance: This term is central to the invention's novelty. The infringement analysis will depend on whether the resin used in Defendant's products falls within the scope of this definition. Practitioners may focus on this term because its construction will define the chemical boundary of the patented technology.
Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The term itself, without further context, suggests a general chemical characteristic rather than a precise numerical limit.
- Evidence for a Narrower Interpretation: The specification states that, "Generally, the level of aromaticity will be less than about 10% by weight of the tackifying resin, preferably less than about 5% by weight and most preferably less than about 3% by weight" (ʼ404 Patent, col. 5:8-12). A party could argue these figures define and limit the scope of "substantially aliphatic."
The Term: "glass transition temperature of greater than 65° C."
Context and Importance: This numerical limitation is a critical feature distinguishing the claimed resin from prior art. A dispute could arise over the methodology used to measure this property.
Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The claim provides a clear numerical floor (greater than 65°C), and the specification lists several increasingly preferred, higher temperatures (e.g., "greater than about 70° C. and most preferably greater than about 75° C.") which could suggest the patentee contemplated a range of values above the floor (ʼ404 Patent, col. 4:2-5).
- Evidence for a Narrower Interpretation: The specification provides a specific testing methodology: "Tg refers to the onset temperature as determined using Dynamic Mechanical Analysis" (ʼ404 Patent, col. 4:11-14). A party could argue that any measurement not using this precise method ("onset temperature" via DMA) is insufficient to prove infringement, narrowing the practical application of the term.
VI. Other Allegations
- Indirect Infringement: The complaint alleges only direct infringement and does not plead facts to support claims for induced or contributory infringement (Compl. ¶14).
- Willful Infringement: The complaint alleges that Defendant has had "knowledge of the '404 patent" since receiving a notice letter on August 27, 2012 (Compl. ¶¶9, 11). The prayer for relief asks the court to declare the case "exceptional" under 35 U.S.C. § 285, which suggests a claim for enhanced damages based on alleged pre-suit knowledge of the patent (Compl. Prayer for Relief D).
VII. Analyst’s Conclusion: Key Questions for the Case
A central evidentiary question will be one of chemical composition: does chemical analysis of the accused Technomelt products, once produced in discovery, reveal the presence of a "substantially aliphatic tackifying resin" with a Tg greater than 65°C, as well as the other components, in the specific weight percentages and concentration ratios required by the asserted claims?
A core issue will be one of definitional scope: how will the court construe the term "substantially aliphatic"? The outcome may turn on whether the court adopts the patent’s preferred numerical percentages for aromaticity (e.g., <10%) as a binding limit on the claim's scope.
A key procedural question relates to pleading sufficiency: given that the complaint was filed in a style that is now disfavored, a threshold issue may be whether the Plaintiff’s general allegations provide sufficient factual substance to meet the plausibility standard for infringement established by the Supreme Court in Iqbal and Twombly.