DCT
1:18-cv-00729
Diesel Tech LLC v. PACCAR Inc
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: Diesel Technologies, LLC (Delaware)
- Defendant: Paccar, Inc. d/b/a Peterbilt Motor Company, and Kenworth Truck Company (Delaware)
- Plaintiff’s Counsel: Devlin Law Firm LLC
- Case Identification: 1:18-cv-00729, D. Del., 05/15/2018
- Venue Allegations: Venue is alleged to be proper in the District of Delaware because Defendant Paccar, Inc. is a Delaware corporation.
- Core Dispute: Plaintiff alleges that Defendant’s heavy-duty truck engines and their exhaust aftertreatment systems infringe a patent related to a method for removing accumulated ash from diesel particulate filters.
- Technical Context: The technology concerns emissions control systems in modern diesel engines, which are critical for meeting environmental regulations by capturing and processing harmful exhaust byproducts like soot and ash.
- Key Procedural History: The complaint does not mention any prior litigation, Inter Partes Review (IPR) proceedings, or specific licensing history related to the patent-in-suit.
Case Timeline
| Date | Event |
|---|---|
| 2003-12-18 | U.S. Patent No. 8,474,246 Earliest Priority Date (German DE 10359395) |
| 2013-07-02 | U.S. Patent No. 8,474,246 Issued |
| 2018-05-15 | Complaint Filed |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 8,474,246 - "METHOD OF OPERATING A PARTICLE FILTER IN THE EXHAUST SYSTEM OF A MOTOR VEHICLE'S INTERNAL COMBUSTION ENGINE," Issued July 2, 2013
The Invention Explained
- Problem Addressed: Standard diesel particulate filters (DPFs) are effective at trapping and periodically burning off carbonaceous soot. However, they also accumulate non-combustible inorganic ash (from sources like engine oil additives) which cannot be removed by the normal soot burn-off procedure. Over time, this ash clogs the filter, increasing exhaust backpressure and eventually rendering the filter useless, requiring costly replacement or off-vehicle cleaning (Compl. ¶12; ’246 Patent, col. 1:30-41).
- The Patented Solution: The patent proposes a distinct "ash reducing procedure" to be performed during vehicle operation. This method involves heating the filter and introducing a "reducing agent" (such as engine fuel) into the exhaust stream. This agent chemically reacts with the non-metallic components of the ash (e.g., sulfates, phosphates), converting them into volatile compounds that can then be expelled from the filter with the exhaust gas, thereby extending the filter's operational life (’246 Patent, Abstract; col. 2:1-4).
- Technical Importance: This method provides a way to regenerate the DPF from not just soot but also performance-degrading ash in situ, potentially avoiding the complex and expensive service facility procedures previously required (’246 Patent, col.1:49-54).
Key Claims at a Glance
- The complaint asserts infringement of claims 1-3 and 7 (Compl. ¶14). Independent claim 1 is the focus.
- Independent Claim 1:
- A method of operating a particle filter in an exhaust system of a motor vehicle internal combustion engine,
- wherein the particle filter collects soot particles and ashes and is re-conditioned in intervals by a soot-burn off procedure,
- and wherein non-combustible ashes are also deposited during operation,
- the method comprising the steps of: reducing, in an ash reducing procedure, the mass of the ash deposits in the particle filter,
- by heating the particle filter and supplying a reducing agent with the exhaust gas,
- which reacts with the ash deposits to chemically convert them,
- such that at least non-metallic constituent parts of the ash deposits are carried out of the particle filter by the exhaust gas.
- The complaint does not explicitly reserve the right to assert other dependent claims.
III. The Accused Instrumentality
Product Identification
- The accused instrumentalities are heavy-duty trucks equipped with specific engines and exhaust aftertreatment systems (ATS). Specifically named are:
- Kenworth T440/T470 trucks equipped with a Paccar PX-9 Engine (Compl. ¶14).
- Peterbilt Model 389 trucks equipped with a Cummins ISX 15 Engine (Compl. ¶14).
Functionality and Market Context
- The complaint alleges these vehicles incorporate an infringing diesel particulate filter system (Compl. ¶17, 18). The functionality is described using marketing materials and operator’s manuals. For example, the Paccar Aftertreatment System (ATS) is depicted as a multi-stage unit including a Diesel Particulate Filter (DPF) and a Selective Catalyst Reduction (SCR) system (Compl. ¶17, Fig. 4). This system performs "Automatic Regeneration" by using an HC Doser to inject fuel (a reducing agent) into the exhaust to generate heat and clean the DPF (Compl. ¶17, Fig. 8). A cutaway diagram shows the Cummins Particulate Filter similarly consists of a Diesel Oxidation Catalyst (DOC) and a DPF, which collects both soot and ash and uses a "self-cleaning" regeneration process (Compl. ¶18, Fig. 13, 14). The complaint alleges these standard regeneration procedures constitute the infringing method.
IV. Analysis of Infringement Allegations
’246 Patent Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| A method of operating a particle filter (4) in an exhaust system of a motor vehicle internal combustion engine (1), wherein the particle filter (4), which collects soot particles and ashes, is re-conditioned, in intervals, by a soot-burn off procedure... | The accused Kenworth and Peterbilt trucks have engines with exhaust systems containing a DPF that collects soot and ash and is re-conditioned by a soot-burn off procedure, also referred to as regeneration. A diagram of the Cummins filter shows it collects "soot particles and ashes" (Fig. 14). | ¶17, 18 | col. 1:13-16 |
| but wherein, in addition to soot, also non-combustible ashes are deposited during operation of the internal combustion engine... | Both soot and non-combustible ash are alleged to accumulate in the accused DPFs during engine operation. An operator's manual states, "Over time, both soot and ash accumulate in the DPF and must be removed" (Fig. 8). | ¶17, 18 | col. 1:30-33 |
| said method comprising the steps of: reducing, in an ash reducing procedure (A), the mass of the ash deposits in the particle filter... | The complaint alleges the accused "soot-burn off procedure" is the claimed "ash reducing procedure," which reduces the mass of deposits by raising exhaust gas temperature to oxidize particulate matter (Fig. 10). | ¶17, 18 | col. 2:1-2 |
| by heating the particle filter and supplying to the particle filter, together with the exhaust gas of the internal combustion engine (1), a reducing agent... | The accused systems heat the filter during regeneration. An HC Doser (in Paccar systems) or fuel injector (in Cummins systems) sprays diesel fuel (the reducing agent) into the exhaust stream upstream of the filter (Fig. 11, 18). | ¶17, 18, 20, 21 | col. 2:2-4 |
| which reacts with the ash deposits so as to chemically convert the ash deposits... | The injected diesel fuel is alleged to react with the ash deposits, chemically converting them by raising the temperature high enough to reduce the ash (Fig. 12). | ¶17, 18 | col. 2:1-2 |
| such that at least non-metallic constituent parts of the ash deposits are carried out of the particle filter (4) by the exhaust gas. | The chemical conversion allegedly allows non-metallic parts of the ash to be carried out by the exhaust gas. This is alleged to occur at temperatures of at least 650°C (Fig. 12). | ¶17, 18 | col. 2:2-4 |
- Identified Points of Contention:
- Scope Question: A central issue may be whether the accused products' standard "soot burn-off" or "regeneration" process constitutes the "ash reducing procedure" required by the claims. The patent's background explicitly states that ash "cannot be removed by the soot burn-off procedure" ('246 Patent, col. 1:31-32), suggesting the two procedures are technically distinct. The complaint, however, appears to equate the accused soot regeneration cycle with the claimed ash reduction method (Compl. ¶17).
- Technical Question: What evidence does the complaint provide that the accused systems' regeneration cycle, which is primarily designed to oxidize carbonaceous soot, also performs the specific function of chemically converting and removing non-metallic inorganic ash as claimed? The complaint cites product manuals discussing the removal of both soot and ash but does not provide direct evidence that the mechanism for ash removal is the chemical conversion claimed in the patent, as opposed to some other physical or incidental effect.
V. Key Claim Terms for Construction
- The Term: "ash reducing procedure"
- Context and Importance: This term is the central feature of the invention, intended to solve a problem (ash accumulation) that the patent distinguishes from the problem solved by a "soot-burn-off procedure." The definition of this term is critical because the infringement case hinges on whether the accused products' standard DPF regeneration cycle, which is designed to burn soot, can also be considered the claimed "ash reducing procedure."
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: A party could argue that any procedure that results in ash reduction via the claimed mechanism (heating and adding a reducing agent) meets the definition, regardless of what the procedure is called (e.g., "regeneration"). The claims themselves define the procedure by its function: "reducing...the mass of the ash deposits" ('246 Patent, cl. 1).
- Evidence for a Narrower Interpretation: A party could argue the term refers to a procedure separate and distinct from a standard soot burn-off. The specification states that ash "cannot be removed by the soot burn-off procedure" ('246 Patent, col. 1:31-32). Further, it suggests the ash reducing procedure may be performed on a different schedule, such as "in connection with each n-th soot burn-off procedure . . . wherein n is a certain positive whole number greater than 1" ('246 Patent, col. 4:28-31), implying the two are not coextensive.
VI. Other Allegations
- Indirect Infringement: The complaint alleges that Defendant induces infringement by providing the accused trucks to partners, customers, and end-users with specific intent or willful blindness, thereby "actively aiding and abetting" the direct infringement by those users (Compl. ¶29). It also alleges contributory infringement, stating the accused trucks contain material components for practicing the patent that are not staple articles of commerce (Compl. ¶30).
- Willful Infringement: Willfulness is alleged based on Defendant's knowledge of the patent and infringement "at least as early as the filing of this Complaint" (Compl. ¶28, 31).
VII. Analyst’s Conclusion: Key Questions for the Case
- A core issue will be one of definitional scope: Can the claimed "ash reducing procedure" be construed to read on a standard "soot burn-off" or "regeneration" cycle, especially when the patent's own specification appears to treat them as distinct solutions to different technical problems?
- A key evidentiary question will follow: Does the accused DPF regeneration cycle, which primarily targets soot, actually achieve the claimed chemical conversion and removal of non-metallic ash components, or is the complaint's theory based on a mischaracterization of how these widely-used emissions systems operate? The resolution may depend on expert testimony regarding the chemical processes that occur during DPF regeneration at high temperatures.