DCT
3:25-cv-00163
Toro Co v. Daye North America Inc
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: The Toro Company (Delaware)
- Defendant: Daye North America Inc. (North Carolina) and Ningbo Daye Garden Machinery Co., Ltd. (China)
- Plaintiff’s Counsel: The Van Winkle Law Firm; MERCHANT & GOULD P.C.
- Case Identification: 3:25-cv-00163, W.D.N.C., 03/07/2025
- Venue Allegations: Venue is alleged to be proper in the Western District of North Carolina because Defendant Daye North America Inc. is incorporated in North Carolina and maintains its principal place of business within the district.
- Core Dispute: Plaintiff alleges that Defendants’ Echo LM-3022SP walk-behind lawnmower infringes a patent related to the design of dual-bladed mowers with a rear-bagging mode.
- Technical Context: The technology concerns walk-behind power lawnmowers with wider, dual-blade cutting decks, which aim to increase mowing efficiency while maintaining the smaller footprint and handling characteristics of traditional single-blade mowers.
- Key Procedural History: The complaint alleges that Defendants had pre-suit knowledge of the patent-in-suit based on a conversation between the parties' respective in-house counsel. Plaintiff also states it has complied with statutory marking requirements by affixing its products with a reference to a patent-listing website.
Case Timeline
| Date | Event |
|---|---|
| 2011-12-06 | ’745 Patent Priority Date |
| 2013-09-24 | ’745 Patent Issue Date |
| 2022-04-06 | Patent marking website referenced in complaint active |
| 2025-02-26 | Patent marking website referenced in complaint active |
| 2025-02-28 | Alleged date of actual notice of the ’745 Patent |
| 2025-03-07 | Complaint Filing Date |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 8,539,745 - "Dual Bladed Walk Power Mower with Rear Bagging Mode," issued September 24, 2013
The Invention Explained
- Problem Addressed: The patent’s background section identifies a market need for walk-behind power mowers with wider cutting swaths to increase user productivity without requiring a move to a much larger riding mower ('745 Patent, col. 1:38-48). It notes that prior attempts at dual-bladed mowers had not achieved a "true rear bagging capability" and that timing systems required to prevent blade collision could warp the relatively light mower decks used in such products ('745 Patent, col. 1:50-60, col. 2:5-11).
- The Patented Solution: The invention discloses a walk-power mower with two side-by-side cutting blades that rotate in the same direction relative to the cutting chamber. This coordinated rotation is designed to cause the grass clippings from both blades to merge into a "single common stream" ('745 Patent, Abstract). This stream is then directed into a single, rearwardly extending discharge tunnel that deposits the clippings into a collection bag positioned between the mower’s handle tubes, mimicking the functionality of a traditional single-blade, rear-bagging mower ('745 Patent, col. 2:20-54).
- Technical Importance: This design sought to provide the efficiency of a wider, 30-inch dual-blade cut while preserving the familiar and spatially efficient rear-bagging architecture common in the consumer and professional walk-mower market ('745 Patent, col. 10:48-67).
Key Claims at a Glance
- The complaint asserts independent claim 1 and dependent claims 2-7 (Compl. ¶24, 43).
- Independent Claim 1 requires:
- A walk power mower with a rear bagging mode.
- A mower deck with a cutting chamber enclosing a pair of rotary side-by-side cutting blades that cut an unbroken swath wider than a single blade’s orbit.
- The blades rotate on vertical axes in the same direction relative to the cutting chamber.
- Grass clippings from the blades merge into a "single common stream" that is "generally rearwardly directed along one side of the cutting chamber."
- A plurality of ground-engaging wheels.
- A handle assembly with a pair of laterally spaced, rearwardly extending handle tubes.
- A power source atop the mower deck.
- "only a single rearwardly extending grass discharge tunnel" for receiving the common stream of clippings.
- The tunnel’s discharge opening is positioned to discharge clippings into a space "laterally between lower portions of the handle tubes."
- A grass collection bag mated to the discharge opening, with its body extending rearwardly "beneath the handle tubes."
III. The Accused Instrumentality
Product Identification
- The Echo LM-3022SP Mower (the "Accused Product") (Compl. ¶18).
Functionality and Market Context
- The Accused Product is a walk-behind power mower featuring a "Dual, Twin-Blade Cutting System" and a 30-inch steel deck (Compl. p. 5). It is marketed with a "3-in-1 Discharge" capability, which includes a rear-bagging mode (Compl. p. 8, Exhibit C). The complaint alleges that Defendant Ningbo Daye manufactures the mower components in China (except the engine) and imports them to the U.S., where Defendant Daye NA assembles the final product and sells it through retailers such as The Home Depot (Compl. ¶¶20-22). An image from the product's operator's manual shows a table of "Mower Functions" which explicitly lists "rear bagging" (Compl. p. 8, Exhibit D at 14).
IV. Analysis of Infringement Allegations
’745 Patent Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| a mower deck having a downwardly facing cutting chamber which encloses a pair of rotary side-by-side cutting blades whose orbits are positioned relative to one another to collectively cut an unbroken swath of grass... wherein the blades rotate about vertical axes in the same direction... so that grass clippings cut by one blade merge with grass clippings cut by the other blade with the merged clippings forming a single common stream of clippings that is generally rearwardly directed along one side of the cutting chamber; | The Accused Product has a deck with two overlapping cutting blades that rotate in the same direction, causing clippings to merge into a common stream directed toward a rear discharge opening on one side of the chamber. A complaint diagram with arrows illustrates the alleged blade rotation and clipping flow. | ¶27, ¶28, ¶29 | col. 7:15-39 |
| a plurality of ground engaging wheels carried on the mower deck for supporting the mower deck for rolling over the ground; | The Accused Product has a plurality of ground engaging wheels. | ¶30 | col. 5:40-41 |
| a handle assembly carried on the mower deck... including a pair of laterally spaced, upwardly inclined, and rearwardly extending handle tubes attached to opposite sides of the mower deck; | The Accused Product has a handle assembly with two spaced, rearwardly extending handle tubes attached to the mower deck. | ¶31 | col. 5:42-48 |
| a power source carried atop the mower deck for rotating the cutting blades; | The Accused Product has a Briggs & Stratton engine mounted on top of the mower deck to power the blades. | ¶32 | col. 5:52-53 |
| wherein the mower deck includes only a single rearwardly extending grass discharge tunnel... the rear discharge opening... is positioned on the mower deck to discharge the common stream of clippings... into a space that is positioned laterally between lower portions of the handle tubes...; | The Accused Product is alleged to have a single "rear discharge chute" that directs clippings into a space located between the handle tubes. A diagram from the operator's manual illustrates the installation of a mulching plug into this chute. | ¶33 | col. 6:3-15 |
| a grass collection bag having a mouth that in the rear bagging mode is mated with the rear discharge opening of the tunnel to receive and collect the common stream of clippings... the grass collection bag extending substantially rearwardly... beneath the handle tubes. | The Accused Product includes a grass collection bag that attaches to the rear discharge opening and extends rearwardly under the handle assembly. A user manual diagram shows the installation of this bag. | ¶34 | col. 6:16-22 |
- Identified Points of Contention:
- Technical Question: A central factual question for the court will be whether the Accused Product's design and operation actually cause clippings from the two blades to form a "single common stream" that is "generally rearwardly directed along one side of the cutting chamber" as claimed. The complaint presents a diagram alleging this specific flow path (Compl. p. 11, Exhibit E), but the actual fluid dynamics of grass clippings within the cutting chamber will be a subject of evidence and expert testimony.
- Scope Questions: The interpretation of "only a single rearwardly extending grass discharge tunnel" may become a point of contention. A defense may question whether other apertures or pathways in the mower deck, such as a blocked side-discharge port, could be characterized as a second "tunnel," thereby avoiding this limitation.
V. Key Claim Terms for Construction
The Term: "single common stream of clippings"
- Context and Importance: This term is the functional heart of the invention, describing the result of the dual-blade, same-direction rotation. The case may turn on whether the flow of clippings in the Accused Product meets this definition. Practitioners may focus on this term because its construction will dictate the type of evidence (e.g., high-speed video, computational fluid dynamics models) needed to prove or disprove infringement.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The patent abstract describes the functional outcome: "grass clippings cut by one blade merge with grass clippings cut by the other blade with the merged clippings forming a single common stream" ('745 Patent, Abstract). This language may support a construction where any combined or intermingled flow from the two blades qualifies.
- Evidence for a Narrower Interpretation: The patent notes that the "circumferential path B" of the clippings "is directed first towards side discharge opening 20 and then to tunnel 24" ('745 Patent, col. 8:26-30). A party could argue that this, along with the depiction in Figure 5, requires a specific, ordered pathway, not just a chaotic mixing of clippings.
The Term: "generally rearwardly directed along one side of the cutting chamber"
- Context and Importance: This phrase qualifies the path of the "single common stream" and is critical for distinguishing the invention from other possible clipping flow patterns. The meaning of "generally" and "along one side" will be debated.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The use of the word "generally" suggests the path is not required to be strictly linear or confined to one quadrant of the deck ('745 Patent, col. 2:29-30). This may support an interpretation that covers any flow path that has a net rearward vector and is predominantly on one side.
- Evidence for a Narrower Interpretation: A party may point to Figure 5, which depicts the entire clipping flow path (arrows B) as contained on the right half of the mower deck ('745 Patent, Fig. 5). This could support an argument that the "stream" must remain substantially on one side for most of its travel within the cutting chamber.
VI. Other Allegations
- Indirect Infringement: The complaint alleges that Defendant Ningbo Daye contributorily infringes by manufacturing and importing mower components (other than the engine) that are "specially made and/or adapted" for use in the infringing mower and are not staple articles of commerce (Compl. ¶64, ¶66-67). It further alleges inducement by Ningbo Daye based on its alleged direction and control over Daye NA to assemble and sell the final product in the U.S. (Compl. ¶68).
- Willful Infringement: The complaint alleges willful infringement by both Defendants, asserting they had actual notice of the ’745 Patent prior to the lawsuit (Compl. ¶36, ¶55). The basis for this allegation is a specific, though undated, "conversation between Toro's in-house counsel and Daye's in-house counsel well before the filing of this complaint" (Compl. ¶65).
VII. Analyst’s Conclusion: Key Questions for the Case
- A central issue will be one of functional operation: Does the accused Echo mower’s dual-blade system, in its rear-bagging mode, actually generate a “single common stream of clippings” that travels “along one side of the cutting chamber” as recited in Claim 1? The resolution of this will depend on factual evidence regarding the behavior of grass clippings inside the mower deck during operation.
- A second core issue will be one of definitional scope: How should the court construe the key phrase “single common stream”? Whether this term requires a highly ordered, consolidated flow, as might be suggested by patent diagrams, or whether it can encompass a more turbulent but merged mixture of clippings, will be a critical question during claim construction.
- A key question for damages will be one of knowledge and intent: Can the Plaintiff substantiate its allegation that a pre-suit conversation between the parties’ in-house counsel provided Defendants with legally effective notice of the ’745 Patent and its alleged infringement? The facts surrounding this event will be pivotal to the claim for willful infringement and potential enhanced damages.