DCT
2:25-cv-13168
Blue 425 LLC v. Laserline Inc
Key Events
Complaint
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: Blue 425 LLC (Delaware)
- Defendant: Laserline Inc. (California), Laserline GmbH (Germany), and WBC Photonics Inc. (New Hampshire)
- Plaintiff’s Counsel: Hecht Partners LLP
- Case Identification: 2:25-cv-13168, E.D. Mich., 10/07/2025
- Venue Allegations: Venue is alleged as proper in the Eastern District of Michigan because Defendant Laserline Inc. has a place of business in the district, allegedly "resides" in the district, and manufactures, offers for sale, sells, or imports the Accused Products in Michigan.
- Core Dispute: Plaintiff alleges that Defendants’ LDMblue and LDFblue Series of blue diode laser systems infringe five U.S. patents related to methods and systems for laser welding, three-dimensional printing, and materials processing.
- Technical Context: The technology at issue involves high-power blue diode lasers, which are particularly effective for processing highly reflective metals like copper due to their high energy absorption at blue wavelengths, a key application in battery and electronics manufacturing.
- Key Procedural History: The complaint does not reference any prior litigation, inter partes review proceedings, or licensing history related to the patents-in-suit.
Case Timeline
| Date | Event |
|---|---|
| 2013-04-29 | Earliest Priority Date for U.S. Patent 11,654,489 |
| 2016-04-29 | Earliest Priority Date for U.S. Patent 11,612,957 |
| 2016-04-29 | Earliest Priority Date for U.S. Patent 11,980,970 |
| 2016-04-29 | Earliest Priority Date for U.S. Patent 12,220,764 |
| 2017-01-31 | Earliest Priority Date for U.S. Patent 10,940,562 |
| 2021-03-09 | U.S. Patent 10,940,562 Issues |
| 2023-04-04 | U.S. Patent 11,612,957 Issues |
| 2023-05-23 | U.S. Patent 11,654,489 Issues |
| 2024-05-21 | U.S. Patent 11,980,970 Issues |
| 2025-02-11 | U.S. Patent 12,220,764 Issues |
| 2025-10-07 | Complaint Filed |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 10,940,562 - “Methods and Systems for Welding Copper Using Blue Laser” (issued March 9, 2021)
The Invention Explained
- Problem Addressed: The patent addresses the significant challenges of welding copper with conventional infrared (IR) lasers. Due to copper's high reflectivity to IR light, high thermal conductivity, and high heat capacity, IR laser welding is inefficient and can be unstable, leading to defects like spatter, micro-explosions, and inconsistent weld quality (ʼ562 Patent, col. 1:16-51).
- The Patented Solution: The invention uses a blue laser beam (wavelengths from approximately 400 nm to 500 nm), which is highly absorbed by copper (ʼ562 Patent, col. 7:5-10). This high absorption enables efficient and stable coupling of laser energy into the material, allowing for high-quality welds to be formed in both "conduction mode" (surface melting) and "keyhole mode" (deep penetration) with minimal defects. The resulting weld is described as having a microstructure and hardness nearly identical to the original copper material (ʼ562 Patent, col. 7:46-54).
- Technical Importance: This technology provides a more reliable and higher-quality method for processing highly reflective metals, a critical need in manufacturing for the electric vehicle, battery, and high-performance electronics industries (ʼ562 Patent, col. 1:21-28).
Key Claims at a Glance
- The complaint asserts independent method Claim 70 (Compl. ¶ 27).
- Claim 70 Elements:
- A method of forming a keyhole weld in copper based materials, comprising:
- placing a work piece in a laser system, wherein the work piece comprises placing a first piece of copper based material in contact with a second piece of copper material; and,
- directing a blue laser beam at the work piece, whereby a keyhole mode weld is formed between the first and second pieces of copper based material;
- wherein the weld comprises a HAZ (heat-affected zone) and a resolidification zone.
U.S. Patent No. 11,612,957 - “Laser-Based Welding Apparatus and Methods” (issued April 4, 2023)
The Invention Explained
- Problem Addressed: This patent focuses on the specific problem of welding stacks of thin copper foils to each other or to thicker bus bars. The patent notes that IR lasers are not reliable for this task and that alternative methods, like ultrasonic welding, can cause process variability and leave behind debris (ʼ957 Patent, col. 2:5-19).
- The Patented Solution: The invention discloses a method for lap welding copper foils using a blue laser beam with a specific set of properties, including minimum power, maximum beam parameter product, maximum spot size, and minimum average and peak intensities. The method also requires exerting a clamping force and providing a non-oxidizing clearing gas to remove plume material and prevent oxidation, all of which are predetermined to produce a high-quality weld with no visible splatter or porosity (ʼ957 Patent, col. 3:51-col. 4:12).
- Technical Importance: The claimed method provides a precise and repeatable process for joining multiple layers of thin copper, a fundamental requirement for manufacturing battery tabs and other electrical interconnects in modern energy storage and electronic devices (ʼ957 Patent, col. 2:9-19).
Key Claims at a Glance
- The complaint asserts independent method Claim 1 (Compl. ¶ 36).
- Claim 1 Elements:
- A method of laser welding a plurality of copper foils together, comprising:
- positioning a plurality of pieces of copper foil (containing at least about 50% copper) in a welding stand;
- exerting a clamping force on the foils;
- directing a blue laser beam with specified properties: (i) at least 500 Watts of power; (ii) a beam parameter product of about 44 mm mrad and less; (iii) a spot size of about 400 µm and less; (iv) an average intensity of at least about 400 kW/cm2; and (v) a peak intensity of at least about 800 kW/cm2;
- lap welding the foils together at a welding speed;
- providing a non-oxidizing beam clearing gas to remove plume material and prevent oxidation;
- wherein the process parameters are predetermined to provide a lap weld with no visible splatter and no visible porosity.
U.S. Patent No. 11,654,489 - “Devices, Systems and Methods for Three-Dimensional Printing” (issued May 23, 2023)
- Technology Synopsis: The patent describes a system for 3D printing or additive manufacturing ("forming a part") using a coherent beam of visible light (400 nm to 750 nm). The system comprises a laser source, an area to hold a metallic substrate, a scanning module to move the beam in a predetermined pattern, and a computer control system to orchestrate the process of melting or softening the substrate to form the part (ʼ489 Patent, col. 20:39-58).
- Asserted Claims: Independent system Claim 1 (Compl. ¶ 46).
- Accused Features: The complaint alleges that the Accused Products, when used for applications such as copper cladding and additive manufacturing, constitute the claimed system (Compl. ¶¶ 49-52). A video allegedly showing the system in operation is cited as evidence for an "area for holding a metallic solid substrate" (Compl. ¶ 50).
U.S. Patent No. 11,980,970 - “Laser Processing Methods for High-Reflectivity Materials” (issued May 21, 2024)
- Technology Synopsis: The patent discloses a blue laser system that includes an X-Y scanning system and an "electronically adjustable lens system." This lens system contains at least three optics, with the second optic being movable along the beam path to provide "on the fly focusing to simulate the performance of an F-Theta lens," which helps maintain a consistent spot size across a large field (ʼ970 Patent, col. 2:35-42; col. 16:47-51).
- Asserted Claims: Independent system Claim 1 (Compl. ¶ 55).
- Accused Features: The complaint alleges the Accused Products contain a blue laser source, an X-Y scanning system, and an "electronically adjustable lens system" that meets the claim limitations (Compl. ¶¶ 58-61). The complaint cites Defendants' marketing materials for its "OTZ_zoom_optics" as evidence of the claimed lens system (Compl. ¶ 61).
U.S. Patent No. 12,220,764 - “Visible Laser Welding of Electronic Packages, Automotive Electrics, Battery and Other Components” (issued February 11, 2025)
- Technology Synopsis: The patent claims a method for joining two metal components with a blue laser where the laser intensity does not need to be "appreciably changed." The method requires the beam to "consist essentially of the predetermined laser intensity" from start to finish and that at least 45% of the beam energy is utilized to form the weld, suggesting a highly stable and efficient process (ʼ764 Patent, col. 14:5-17).
- Asserted Claims: Independent method Claim 17 (Compl. ¶ 64).
- Accused Features: The complaint alleges the Accused Products perform the claimed method by providing a stable, predetermined laser intensity suitable for joining metal components, and that they incorporate the requisite scanner and focusing optics (Compl. ¶¶ 67-71). A video is cited to support the allegation of providing a source of a blue laser beam to a weld site (Compl. ¶ 68).
III. The Accused Instrumentality
Product Identification
- The accused instrumentalities are the Laserline LDMblue Series and the Laserline LDFblue Series industrial diode laser systems (Compl. ¶ 1). The complaint includes images of the Accused Products as Exhibits 7 and 8 (Compl. ¶ 26).
Functionality and Market Context
- The complaint describes the Accused Products as high-power blue diode laser systems operating at a wavelength of approximately 450 nm (Compl. ¶ 30). This wavelength is alleged to allow for efficient laser processing of highly reflective metals like copper (Compl. ¶ 30). The products are marketed and sold for industrial applications including additive manufacturing, welding, brazing, cladding, and 3D printing (Compl. ¶¶ 5, 12). The complaint specifically alleges they are used to weld copper busbars and electrical contacts (Compl. ¶ 32). The systems are also alleged to incorporate or be used with scanning modules, computer control systems, and adjustable zoom optics (Compl. ¶¶ 51, 52, 61).
IV. Analysis of Infringement Allegations
’940,562 Patent Infringement Allegations
| Claim Element (from Independent Claim 70) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| A method of forming a keyhole weld in copper based materials, the method comprising: a. placing a work piece in a laser system; wherein the work piece comprises placing a first piece of copper based material in contact with a second piece of copper material; and, | The Accused Products are allegedly used in laser systems to weld work pieces, such as two pieces of copper-based material like copper busbars and electrical contacts (Compl. ¶ 32). | ¶32 | col. 17:20-24 |
| b. directing a blue laser beam at the work piece, whereby a keyhole mode weld is formed between the first piece of copper based material and the second piece of copper based material; | The Accused Products allegedly direct a blue laser beam operating at around 450 nm at a work piece to form a keyhole mode weld between two pieces of copper material (Compl. ¶ 33). | ¶33 | col. 18:26-34 |
| wherein the weld comprises a HAZ and a resolidification zone. | The process allegedly forms a heat-affected zone (HAZ) and a re-solidification zone (Compl. ¶ 33). | ¶33 | col. 18:23-25 |
Identified Points of Contention
- Scope Questions: The asserted claim is a method claim, while the accused instrumentality is a laser system. A central question will be whether Defendants are alleged to be direct infringers (by performing the method) or indirect infringers (by inducing or contributing to infringement by their customers). The complaint's allegations focus on how the systems "enable controlled laser welding," suggesting the primary theory is likely induced infringement (Compl. ¶ 31).
- Technical Questions: The complaint alleges the formation of a "keyhole mode weld" (Compl. ¶ 33). A technical dispute may arise regarding the evidence required to prove that the process enabled by the Accused Products meets the patent's technical definition of a keyhole weld, as distinct from a conduction mode weld.
’612,957 Patent Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| a. positioning a plurality of pieces of copper foil in a welding stand... b. exerting a clamping force on the plurality of pieces of copper foil to clamp the pieces of foil together in the welding stand; | The complaint alleges the Accused Products "teach a method of laser welding a plurality of copper foils" and "each exert a clamping force" on the foils to clamp them in a welding stand (Compl. ¶¶ 39, 40). | ¶¶39, 40 | col. 3:51-60 |
| c. directing a blue laser beam... wherein the laser beam has the following properties: i. at least 500 Watts of power; ii. a beam parameter product of about 44 mm mrad and less; iii. a spot size of about 400 µm and less; iv. an average intensity...; v. a peak intensity... | The Accused Products are alleged to direct a blue laser beam (Compl. ¶ 41) and to possess a laser beam with the specifically claimed properties regarding power, beam parameter product, spot size, and intensity (Compl. ¶ 42). | ¶¶41, 42 | col. 3:61-col. 4:5 |
| e. providing a non-oxidizing beam clearing gas in a space along the laser beam path... wherein clearing gas removes plume material... and prevents oxidation... | The complaint does not provide sufficient detail for analysis of this element. | N/A | col. 4:6-10 |
| f. wherein the welding speed, clamping force, and a flow rate of the non-oxidizing clearing gas, are predetermined to thereby provide a lap weld having no visible splatter and no visible porosity. | The complaint does not provide sufficient detail for analysis of this element. | N/A | col. 4:10-12 |
Identified Points of Contention
- Scope Questions: A significant question of scope arises from the allegations for elements (a) and (b). It is unclear how a laser system itself performs the physical acts of "positioning" foils and "exerting a clamping force," as these actions are typically performed by an external fixture or welding stand. The allegation may suggest a dispute over whether the claim can be read on the laser system alone or requires the combination with other components.
- Technical Questions: The complaint makes no specific factual allegations to support the elements requiring a "non-oxidizing beam clearing gas" and the achievement of a weld with "no visible splatter and no visible porosity." These omissions raise the question of what evidence, if any, the complaint provides to suggest these required steps and outcomes are met by the accused method.
V. Key Claim Terms for Construction
The ’562 Patent
- The Term: "keyhole mode weld"
- Context and Importance: This term is the central feature of asserted Claim 70 and distinguishes the claimed method from other forms of laser welding, such as conduction mode. The infringement analysis will depend on whether the process enabled by the Accused Products falls within the technical definition of "keyhole mode weld."
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The specification describes keyhole welding as a process where "the laser energy is absorbed so rapidly that it melts and vaporizes the material being welded," creating a "hole or capillary where the laser beam can propagate and be absorbed" (ʼ562 Patent, col. 8:65-col. 9:4). Practitioners may argue this covers any process that achieves deep penetration via material vaporization, not just a specific morphology.
- Evidence for a Narrower Interpretation: The specification contrasts keyhole welding with conduction mode welding, which produces a "spherical shape" weld (ʼ562 Patent, col. 8:56-58). Figure 11 specifically illustrates a "metal/vapor plasma in the keyhole" (ʼ562 Patent, Fig. 11), suggesting the term may be construed to require the presence of such a plasma-filled capillary, a potentially narrower definition.
The ’957 Patent
- The Term: "no visible splatter and no visible porosity"
- Context and Importance: This limitation in Claim 1 defines the required outcome and quality of the weld. The case may turn on the standard of "visibility"—whether it means visible to the naked eye, under standard magnification, or an absolute standard.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The patent does not define a specific inspection standard or magnification level for "visible." This may support an argument that the term should be given its plain and ordinary meaning, referring to defects observable by a person of ordinary skill in the art under normal inspection conditions.
- Evidence for a Narrower Interpretation: The parent '562 patent, which shares a specification, repeatedly emphasizes the goal of creating "essentially perfect welds" (ʼ562 Patent, Abstract). A party may argue that "no visible" should be interpreted in this context to mean a very high, near-perfect standard of quality, potentially requiring inspection under magnification to confirm the absence of defects.
VI. Other Allegations
Indirect Infringement
- The complaint explicitly pleads induced infringement under 35 U.S.C. § 271(b) for all five asserted patents (Compl. ¶¶ 34, 44, 53, 62, 72). The allegations state that Defendants have knowledge of the patents (at least from the date the complaint was filed) and intentionally induce infringement by "actively encourage[ing] and instruct[ing] its customers and end users to use the Accused Products in ways that directly infringe," citing Defendants' websites, product datasheets, and other marketing materials (Compl. ¶¶ 31-33, 39).
Willful Infringement
- The complaint does not contain the word "willful." However, it requests "enhanced damages" under 35 U.S.C. § 284 and a finding that the case is "exceptional" for an award of attorneys' fees under § 285 (Compl. p. 16). The factual basis for enhanced damages appears to be based on post-suit knowledge of the patents.
VII. Analyst’s Conclusion: Key Questions for the Case
- A core issue will be one of divided infringement responsibility: For the asserted method claims, can Plaintiff establish that Defendants are directly liable by performing every claimed step, including those related to workpiece handling (e.g., "placing," "exerting a clamping force")? Or will the case depend entirely on a theory of induced infringement, requiring proof that Defendants' instructions and marketing materials lead customers to perform the complete, patented methods?
- A second central issue will be one of evidentiary sufficiency: The complaint makes broad allegations mapping the Accused Products to the patents but provides limited specific evidence for certain claim limitations (e.g., the "non-oxidizing clearing gas" and "no visible splatter" requirements of the '957 patent). A key question will be whether discovery produces technical documentation, test data, and customer usage evidence sufficient to demonstrate that the Accused Products, as sold and used, meet every specific technical and functional requirement of the asserted claims.
- Finally, the case may present a question of definitional scope: The dispute will likely involve construing key technical terms such as "keyhole mode weld" ('562 patent) and "on the fly focusing to simulate the performance of an F-Theta lens" ('970 patent). The outcome will depend on whether the operational characteristics of the Accused Products fall within the scope of these terms as defined by the patent's intrinsic evidence.