DCT
3:26-cv-01148
Danco LLC v. Hangzhou Great Star Industrial Co Ltd
Key Events
Complaint
Table of Contents
complaint Intelligence
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: Danco, LLC (Delaware) and Edward Lenart (Michigan)
- Defendant: Hangzhou Great Star Industrial Co., Ltd. (China)
- Plaintiff's Counsel: Scheef & Stone, LLP
- Case Identification: 3:26-cv-01148, N.D. Tex., 04/10/2026
- Venue Allegations: Venue is alleged to be proper because the defendant is a foreign corporation not resident in the U.S., which makes venue proper in any judicial district.
- Core Dispute: Plaintiffs allege that Defendant's Kobalt-branded pry bars infringe two patents related to the structural features of pry bar tools, specifically the design of the claw and pry panel.
- Technical Context: The dispute concerns the mechanical design of hand tools used in construction and demolition for prying apart structures and removing fasteners.
- Key Procedural History: The complaint alleges a history between the parties, including a letter dated October 14, 2024, in which Defendant responded to infringement allegations by asserting the invalidity of the '552 Patent based on prior art. The complaint notes this prior art was previously considered and overcome by the patent examiner during prosecution. The parties also engaged in settlement discussions between October 2024 and February 2026, which were ultimately unsuccessful.
Case Timeline
| Date | Event |
|---|---|
| 2018-09-05 | Earliest Priority Date for '552 and '310 Patents |
| 2024-05-14 | U.S. Patent No. 11,981,552 Issues |
| Spring 2024 | Plaintiff Danco becomes aware of the accused HGS Pry Bars |
| 2024-10-14 | Defendant Hangzhou Great Star sends letter to Danco asserting invalidity of the '552 Patent |
| 2025-07-29 | U.S. Patent No. 12,371,310 Issues |
| 2026-04-10 | Complaint Filed |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 11,981,552, "Pry Bar Assembly," Issued May 14, 2024
The Invention Explained
- Problem Addressed: The patent background describes the need for construction wrecking tools capable of assisting a person in pulling apart structures, such as framing and decking, that are held together by nails and other fasteners '552 Patent, col. 1:40-44
- The Patented Solution: The invention is a pry bar assembly with a specific geometry designed for strength and leverage. It comprises a handle-like "first section" and a "second section" with a "first claw portion" '552 Patent, col. 9:36-39 A key feature is an "asymmetrically bowed" pry panel located on the claw portion, which, along with other structural elements like crests and ridges, is designed to provide greater strength and rigidity without increasing the tool's weight or thickness '552 Patent, col. 3:20-23 '552 Patent, col. 4:3-8 Figure 2 illustrates the relationship between the first section, the first claw portion, and the asymmetrically bowed pry panel '552 Patent, Fig. 2
- Technical Importance: The design purports to create a stronger, more rigid pry bar that will not easily bend during use, allowing for a more lightweight tool '552 Patent, col. 4:11-16
Key Claims at a Glance
- The complaint asserts independent claim 1 and a number of dependent claims '552 Patent, col. 9:36-61 Compl. ¶25
- Independent Claim 1 Elements:
- A pry tool comprising: a first section having a longitudinal axis in a first plane;
- a second section comprising a first claw portion;
- wherein the first claw portion comprises a first plate and a pry panel;
- wherein the first plate comprises a first lateral edge, a second lateral edge... and a first end;
- wherein the first lateral edge and the second lateral edge are disposed in a second plane substantially perpendicular to the first plane;
- wherein the pry panel is asymmetrically bowed inwardly toward the first section from the first plate and is connected at a first end to the first plate and at a second end to the first plate; and
- wherein the first face comprises a tapered portion extending to the first end of the first plate.
- The complaint alleges infringement of dependent claims 2, 7, 9-11, 15-17, 19, 20, 22, 23, 25, 29, 33, 37, 46, and 47 Compl. ¶25
U.S. Patent No. 12,371,310, "Pry Bar Assembly," Issued July 29, 2025
The Invention Explained
- Problem Addressed: As a continuation of the application leading to the '552 Patent, the '310 Patent addresses the same technical problem of providing an improved construction wrecking tool for prying apart structures '310 Patent, col. 1:44-49
- The Patented Solution: The '310 Patent claims a similar pry tool with a handle section and a claw section. The claimed solution again focuses on the geometry of the claw, specifically a first claw portion with lateral edges in a plane perpendicular to the handle's plane, and an "asymmetrically bowed" pry panel that "extends inwardly from the first claw portion toward the handle section" '310 Patent, col. 4:50-65 This configuration is intended to provide leverage and structural integrity.
- Technical Importance: The claimed design aims to enhance the mechanical advantage and durability of a pry bar, allowing it to function effectively as a "wrecking tool" for deconstruction purposes '310 Patent, col. 4:15-18
Key Claims at a Glance
- The complaint asserts independent claim 1 and a number of dependent claims '310 Patent, col. 4:50-65 Compl. ¶32
- Independent Claim 1 Elements:
- A pry tool comprising: a handle section comprising a longitudinal axis in a first plane;
- a claw section extending from the handle section, the claw section comprising a first claw portion and a pry panel;
- wherein the first claw portion comprises a first lateral edge, a second lateral edge, and a first end;
- wherein the first lateral edge and the second lateral edge are disposed in a second plane substantially perpendicular to the first plane;
- wherein the pry panel is asymmetrically bowed and extends inwardly from the first claw portion toward the handle section; and
- wherein the pry panel is connected at a first end to the first claw portion and at a second end to the first claw portion.
- The complaint alleges infringement of dependent claims 2, 3, 8-12, 15-19, 22, and 24-26 Compl. ¶32
III. The Accused Instrumentality
Product Identification
The accused products are the Kobalt Pry Bar Model No. 66744 (Lowe's sku 5144457) and other similarly branded pry bars manufactured by Defendant (collectively "HGS Pry Bars") Compl. ¶1
Functionality and Market Context
The HGS Pry Bars are hand tools sold for construction and demolition tasks Compl. ¶1 The complaint alleges that Defendant intends for these products to be competitive with Plaintiffs' own patented products, which are sold under the Zenith brand at retailers including Lowe's and Home Depot Compl. ¶16
IV. Analysis of Infringement Allegations
The complaint alleges that the HGS Pry Bars literally infringe the asserted claims Compl. ¶25 Compl. ¶32 The complaint references, but does not include, exhibits with annotated photographs purporting to show this infringement Compl. ¶24 Compl. ¶31 An annotated version of Figure 2 from the '552 Patent is provided in the complaint to illustrate an example of a tool within the scope of claim 1, with callouts for the "First Section," "Asymmetrically Bowed Pry Panel," and "First Claw Portion" Compl. p. 4
'552 Patent Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| a first section having a longitudinal axis in a first plane | The complaint alleges the Kobalt Pry Bar includes a first section with a longitudinal axis in a first plane. | ¶14; ¶25 | col. 3:2-6 |
| a second section comprising a first claw portion | The Kobalt Pry Bar is alleged to have a second section that includes a first claw portion. | ¶14; ¶25 | col. 3:7-9 |
| wherein the first claw portion comprises a first plate... having first and second lateral edges disposed in a second plane substantially perpendicular to the first plane | The first claw portion of the accused product is alleged to comprise a first plate with lateral edges in a second plane perpendicular to the first plane. | ¶14; ¶25 | col. 3:13-16 |
| a pry panel that is asymmetrically bowed inwardly toward the first section from the first plate and is connected to the first plate at a first end and connected to the first plate at a second end | The accused product is alleged to have a pry panel that is asymmetrically bowed toward the first section and connected to the first plate at two ends. | ¶14; ¶25 | col. 3:20-29 |
'310 Patent Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| a handle section having a longitudinal axis in a first plane | The complaint alleges the Kobalt Pry Bar includes a handle section with a longitudinal axis in a first plane. | ¶15; ¶32 | col. 3:7-10 |
| a claw section extending from the handle section, the claw section comprising (a) first claw portion comprising first and second lateral edges disposed in a second plane substantially perpendicular to the first plane | The accused tool is alleged to have a claw section with a first claw portion whose lateral edges are in a second plane perpendicular to the first plane of the handle section. | ¶15; ¶32 | col. 3:11-19 |
| (b) a pry panel that is asymmetrically bowed and extends inwardly from the first claw portion toward the handle section | The accused product allegedly incorporates an asymmetrically bowed pry panel that extends inwardly toward the handle section. | ¶15; ¶32 | col. 3:25-28 |
| and is connected to the first claw portion at a first end and connected to the first claw portion at a second end | The pry panel on the accused tool is allegedly connected at two ends to the first claw portion. | ¶15; ¶32 | col. 3:25-28 |
- Identified Points of Contention:
- Scope Questions: A central question may be whether the accused pry bar's panel is "asymmetrically bowed" within the meaning of the claims. The analysis will depend on the degree and nature of asymmetry required by the claim language as construed by the court.
- Technical Questions: The complaint alleges literal infringement of every element Compl. ¶25 Compl. ¶32 The defense may challenge whether the geometric relationships claimed-such as the "substantially perpendicular" orientation of the first and second planes-are precisely met in the accused products.
V. Key Claim Terms for Construction
- The Term: "asymmetrically bowed"
- Context and Importance: This term appears in the independent claim of both asserted patents and describes a key structural feature of the invention. The infringement analysis will likely depend heavily on the scope of this term, as a dispute may arise over whether the curvature of the pry panel on the accused HGS Pry Bars meets this limitation.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The claim language itself does not specify a particular degree or type of asymmetry, which may support a broader construction covering any non-symmetrical bow.
- Evidence for a Narrower Interpretation: The specification describes a specific embodiment where the pry panel "may form a triangle" and "includes a short leg 54 and a long leg 56" '552 Patent, col. 3:24-27 This detailed description of a two-legged, unequal structure could be used to argue for a narrower construction limited to this type of asymmetry.
VI. Other Allegations
- Indirect Infringement: The complaint alleges active inducement, stating that Defendant sells the HGS Pry Bars to retailers like Lowe's with the intention that they will then sell the infringing products to end-users in the U.S. Compl. ¶26 Compl. ¶33
- Willful Infringement: The complaint alleges willful infringement based on Defendant's alleged actual notice of the patents. For the '552 Patent, notice is alleged as of at least October 14, 2024, the date of Defendant's letter to Danco Compl. ¶28 For the '310 Patent, notice is alleged as of its issuance on July 29, 2025, based on Defendant's prior notice of the pending application from which it issued Compl. ¶35
VII. Analyst's Conclusion: Key Questions for the Case
- A core issue will be one of claim construction: how will the court define "asymmetrically bowed"? The outcome may depend on whether the definition is broad enough to cover any non-symmetrical curve or is limited to a more specific geometry, such as the unequal-leg structure described in the patent's detailed description.
- A key validity question will be one of obviousness: Defendant has already signaled its intent to challenge the patents' validity based on prior art 'Compl. ¶19 While the complaint notes this art was overcome during prosecution, the court will have to consider whether Defendant can present clear and convincing evidence that the claimed combination of features would have been obvious.
- A central factual question will be one of technical proof: what evidence will Plaintiffs provide to demonstrate that the accused pry bars meet, with precision, the specific geometric and relational limitations of the claims, such as the "substantially perpendicular" orientation of the claw's lateral edges relative to the handle's plane?
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