DCT
1:24-cv-03556
Ningbo Yingli Electrical Appliances Co Ltd v. Flexlatch LLC
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: Ningbo Yingli Electrical Appliances Co., Ltd. d/b/a Yingli Direct (China)
- Defendant: FlexLatch LLC (North Carolina)
- Plaintiff’s Counsel: Tabet DiVito & Rothstein LLC; ScienBiziP, P.C.
- Case Identification: 1:24-cv-03556, N.D. Ill., 05/01/2024
- Venue Allegations: Plaintiff alleges venue is proper because Defendant conducts business in Illinois, interfered with Plaintiff's sales to Illinois residents, and previously filed a related lawsuit against Plaintiff in the same district.
- Core Dispute: Plaintiff seeks a declaratory judgment that its door latch products do not infringe Defendant's patent, alleging Defendant has made knowingly false infringement complaints to Amazon, resulting in the repeated delisting of Plaintiff's products.
- Technical Context: The technology at issue involves simple mechanical door latches designed to hold a door ajar, creating an opening wide enough for small pets like cats to pass through while preventing access by larger pets or small children.
- Key Procedural History: The complaint details a history of conflict, including a prior copyright lawsuit filed by FlexLatch against Yingli Direct (Case No. 23-cv-06296, N.D. Ill.). Following a court order in that case that allowed Yingli Direct to resume sales, FlexLatch allegedly began lodging patent infringement complaints with Amazon, leading to multiple delistings of Yingli Direct's products from the e-commerce platform.
Case Timeline
| Date | Event |
|---|---|
| 2021-05-12 | ’741 Patent Priority Date |
| 2023-08-30 | Flexlatch files prior copyright lawsuit against Yingli Direct |
| 2023-10-24 | ’741 Patent Issue Date |
| 2023-11-29 | Court modifies preliminary injunction in prior case, allowing Yingli Direct to resume sales |
| 2024-02-09 | Yingli Direct receives first notice from Amazon of product delisting based on ’741 patent |
| 2024-04-09 | Yingli Direct receives second notice from Amazon of product delisting |
| 2024-04-10 | Yingli Direct receives third notice from Amazon of product delisting |
| 2024-05-01 | Complaint for Declaratory Judgment filed |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 11,795,741 - "Door Holder", issued October 24, 2023
The Invention Explained
- Problem Addressed: The patent describes a need for a device that can reliably hold a door open at a fixed width, allowing a small pet to pass through while preventing larger pets or a small child from doing so (’741 Patent, col. 2:44-48). The design also seeks to enable simple, one-handed installation (’741 Patent, col. 2:53-56).
- The Patented Solution: The invention is a door holder comprising three main components: a "flexlatch" (a flat, flexible strap), a "rigid plate," and a "striker plate coupler" (’741 Patent, col. 2:59-61). The flexlatch loops over a doorknob, while the coupler at the other end engages the door frame's striker plate. The central innovation is the "rigid plate," described as a stiffener embedded within one end of the flexible strap, which "establish[es] the fixed opening width by preventing a portion of the proximal 290 end of the flexlatch 200 from bending" (’741 Patent, col. 3:22-28). The complaint reprints Figure 2A from the patent, which depicts the rigid plate (230) embedded within the flexlatch (200) (Compl. ¶23).
- Technical Importance: The inclusion of a rigid component aims to solve a potential issue with purely flexible latches, which might bend or stretch under pressure, thereby failing to maintain the desired fixed opening width between the door and its frame (’741 Patent, col. 3:25-28).
Key Claims at a Glance
- The complaint identifies Claim 1 as the sole independent claim of the ’741 Patent (Compl. ¶26).
- The essential elements of Claim 1 include:
- a flat strap of flexible material, a rigid plate, and a striker plate coupler;
- the rigid plate having a first end portion joining with a portion of a proximal end of the flat strap;
- a striker plate coupler formed at a second end of the rigid plate; and
- "wherein the rigid plate establishes the fixed opening width by preventing the portion of the proximal end of the flat strap from bending."
- The complaint alleges that all other claims of the patent are dependent on Claim 1 and therefore incorporate the "rigid plate" limitation (Compl. ¶29).
III. The Accused Instrumentality
Product Identification
- The products at issue are various door latches sold by Yingli Direct on Amazon under multiple Amazon Standard Identification Numbers (ASINs) (Compl. ¶19, ¶52).
Functionality and Market Context
- The complaint describes the accused products as being "constructed from a single and continuous flexible piece of plastic" (Compl. ¶16). One end is looped to attach to a door handle, while the other end has a series of holes into which an adjustable metal pin can be screwed; this pin engages the door frame to hold the door open (Compl. ¶16-17). The complaint provides an image demonstrating the product's use, showing it stretched between a doorknob and the door frame (Compl. ¶15). Crucially, the complaint alleges that "both ends of the plastic strap are flexible and thus can bend" (Compl. ¶30).
- The complaint alleges the door latch is Yingli Direct's "flagship product," which formerly generated over 60% of its Amazon store revenue and was a top-10 bestseller in its product category before being delisted (Compl. ¶70-71).
IV. Analysis of Infringement Allegations
This action is for a declaratory judgment of non-infringement. The following table summarizes Plaintiff Yingli Direct's key non-infringement arguments as presented in the complaint.
’741 Patent Non-Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Non-Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| a ... rigid plate ... | The complaint alleges the product is made of a "single and continuous flexible piece of plastic" and does not have the required rigid plate. | ¶3, ¶30, ¶84 | col. 2:60 |
| the rigid plate having at least a first end portion joining with at least a portion of a proximal end of the flat strap... | The product is alleged to be a unitary, flexible strap, lacking a distinct "rigid plate" component joined to it. The complaint states the metal grommets and pin are not "plates" and do not have the required structure. | ¶16, ¶67 | col. 5:24-28 |
| wherein the rigid plate establishes the fixed opening width by preventing the portion of the proximal end of the flat strap from bending. | The complaint alleges that the product is entirely flexible and provides a visual demonstrating that the strap can be bent. It further alleges the product's components do not prevent the strap from bending as claimed. | ¶3, ¶18, ¶67 | col. 5:39-42 |
Identified Points of Contention
- Scope Questions: The dispute raises a primary question of claim scope: does the term "rigid plate" as claimed in the ’741 patent require a distinct, embedded stiffener as shown in the patent's figures, or could it be interpreted more broadly to read on the metal grommets and adjustable pin present in the accused product? The complaint argues for the narrower interpretation, stating these components are not "plates" and lack the claimed structure (Compl. ¶67).
- Technical Questions: A central technical question is whether the accused product functions in the manner required by the claim. The complaint alleges the product is entirely flexible, a point it supports with a photograph showing the product being bent by hand (Compl. p. 2, ¶3). The court may need to determine if the accused product, in its operational state, actually performs the claimed function of "preventing the portion of the proximal end of the flat strap from bending" to "establish[] the fixed opening width."
V. Key Claim Terms for Construction
- The Term: "rigid plate"
- Context and Importance: This term appears to be the dispositive element of the non-infringement dispute. Plaintiff's entire case, as pleaded, is based on the assertion that its product "indisputably lack[s] a 'rigid plate'" (Compl. ¶3). The construction of this term will therefore be central to resolving whether Defendant's infringement accusations were baseless, which in turn impacts the related state law claims.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The patent provides a definition for "rigid," stating it "may refer to an object or material which is inflexible" (’741 Patent, col. 4:65-66). Defendant may argue that any "inflexible" component that performs a stiffening function, such as the accused product's metal pin and grommets, meets this definition, even if it is not a flat "plate."
- Evidence for a Narrower Interpretation: The specification consistently describes the "rigid plate 230" as a "stiffener that may be embedded within the flexlatch 200" (’741 Patent, col. 3:22-24). The patent drawings, which the complaint reproduces, show the "rigid plate" (230) as a discrete component contained within the flexible strap (200) (Compl. ¶23). Plaintiff may argue this context limits the term to a specific embedded structure, which its product allegedly lacks (Compl. ¶67).
VI. Other Allegations
- Willful Infringement: The complaint does not allege willful patent infringement in the traditional sense. Instead, it alleges that Defendant's conduct in making "knowingly false" representations of infringement to Amazon was "willful," "malicious," and constitutes "egregious, intentional misconduct" (Compl. ¶3, ¶6, ¶95). These allegations form the basis for seeking attorney's fees under 35 U.S.C. § 285 for an "exceptional case" and for supporting state law claims of tortious interference and deceptive trade practices (Compl. ¶86, ¶95-103).
VII. Analyst’s Conclusion: Key Questions for the Case
- A core issue will be one of claim construction: how broadly will the court construe the term "rigid plate"? Will its meaning be limited to an embedded stiffener as illustrated in the patent's preferred embodiment, or can it encompass the metal grommets and pin of the accused product, which Plaintiff asserts are structurally and functionally distinct?
- A key evidentiary question will be one of factual non-infringement: does the accused product, alleged to be a "single and continuous flexible piece of plastic," actually contain any structure that meets the functional limitation of "preventing the portion of the proximal end of the flat strap from bending," as required by Claim 1?
- Finally, the case presents a significant question regarding commercial conduct: assuming a finding of non-infringement, were Defendant's repeated patent infringement complaints to a third-party marketplace like Amazon, which resulted in the delisting of a competitor's product, made in bad faith sufficient to constitute tortious interference or a violation of state deceptive trade practice laws?