DCT
4:25-cv-00336
Bay Materials LLC v. Dyna Flex Ltd
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: Bay Materials, LLC (California)
- Defendant: Dyna Flex, Ltd. and Ortho Solutions, LC (Missouri)
- Plaintiff’s Counsel: Hepler Broom; Finnegan, Henderson, Farabow, Garrett & Dunner, LLP
- Case Identification: 4:25-cv-00336, E.D. Mo., 03/18/2025
- Venue Allegations: Venue is alleged to be proper in the Eastern District of Missouri because Defendants are incorporated and reside in the state of Missouri and within this judicial district.
- Core Dispute: Plaintiff alleges that Defendant’s multilayer polymer sheet material and the resulting orthodontic aligners infringe a patent related to dual-shell thermoplastic materials for dental appliances.
- Technical Context: The technology involves advanced multi-layer polymers designed for fabricating clear orthodontic aligners, a product category with significant commercial value in the dental and orthodontic markets.
- Key Procedural History: The complaint alleges a history beginning in late 2018, when Defendant evaluated Plaintiff's commercial product, Zendura FLX. Plaintiff sent a notice letter to Defendant on August 14, 2024, alleging infringement, which was followed by communications between counsel. The patent-in-suit, attached as an exhibit to the complaint, includes an Inter Partes Review (IPR) Certificate issued on August 7, 2024, which confirmed the patentability of most of the asserted claims.
Case Timeline
| Date | Event |
|---|---|
| 2017-05-31 | '630 Patent Priority Date |
| 2018-11-01 | Bay Materials announces commercial release of Zendura FLX |
| 2021-03-16 | '630 Patent Issue Date |
| 2022-07-11 | Inter Partes Review (IPR2022-01214) filed against '630 Patent |
| 2024-03-08 | Defendant announces its SmileShare Aligners will use Glacier GX3 |
| 2024-04-09 | Defendant offers Glacier GX3 for sale in a "Dealer Specials" brochure |
| 2024-08-07 | IPR Certificate issues, confirming patentability of claims 1-4, 7-11, 13 |
| 2024-08-14 | Bay Materials sends notice letter to Defendant regarding '630 Patent |
| 2024-09-12 | Counsel for Defendant responds to notice letter |
| 2025-03-18 | Complaint Filing Date |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 10,946,630 - "Dual Shell Dental Appliance and Material Constructions"
- Issued: March 16, 2021
The Invention Explained
- Problem Addressed: The patent describes a need for improved materials for orthodontic appliances. Existing materials are described as having performance deficiencies, such as applying excessive initial force that quickly decays, leading to patient discomfort and ineffective tooth movement, or being susceptible to staining and stress cracking (ʼ630 Patent, col. 1:26-48).
- The Patented Solution: The invention is a multi-layer polymeric sheet composition for forming dental appliances. It features at least two rigid outer layers (A and C) and a softer, elastomeric middle layer (B) (ʼ630 Patent, col. 1:50-59). The rigid outer "shells" are intended to accurately engage the teeth, while the elastomeric core provides a more consistent and sustained restorative force over time, improving both comfort and therapeutic effectiveness (ʼ630 Patent, col. 5:40-47).
- Technical Importance: This layered construction attempts to resolve a fundamental trade-off in aligner design by combining the precise force application of a rigid material with the sustained, gentle pressure and flexibility of an elastomer (ʼ630 Patent, col. 4:56-65).
- Analogy: The structure functions like a leaf spring encased in a hard shell. The outer shells give the appliance its precise shape and rigidity to grip the teeth, while the inner elastomeric layer acts as the spring, providing the continuous, gentle force needed to move the teeth.
Key Claims at a Glance
- The complaint asserts independent claim 1 and dependent claims 2, 7-9, and 12-13.
- Independent Claim 1 requires:
- A polymeric sheet composition, comprising: at least two outer layers A and C and an elastomeric inner layer B,
- wherein one or more of the outer layers A and C is a polyester or co-polyester having a flexural modulus of from about 1,000 MPa to 2,500 MPa,
- the inner layer B is comprised of an elastomeric material having a hardness from about A80 to D75, and
- the polymeric sheet composition has a flexural modulus of from about 750 MPa to 2,000 MPa.
- The complaint does not explicitly reserve the right to assert other claims, but this is standard practice.
III. The Accused Instrumentality
Product Identification
- The accused instrumentalities are the "Glacier® GX3" multilayer polymeric sheets and dental appliances made from this material, including the "SmileShare™" dental aligners (Compl. ¶2).
Functionality and Market Context
- The Glacier GX3 product is marketed as a "three layer[]" or "multi-layer material" that combines "durable outer layers with a soft inner layer" or "an elastomeric inner layer" (Compl. ¶8, ¶29, ¶32). A marketing graphic included in the complaint shows an exploded view of these distinct layers (Compl. ¶29, p. 9).
- The material is sold both as raw sheets for fabrication and as finished, custom-made SmileShare™ dental aligners sold to orthodontists (Compl. ¶8, ¶28, ¶40). The complaint alleges that Defendant copied Plaintiff's own "industry-leading" Zendura FLX product to create the Accused Products (Compl. ¶1, ¶8).
IV. Analysis of Infringement Allegations
’630 Patent Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| A polymeric sheet composition, comprising: at least two outer layers A and C and an elastomeric inner layer B, | The Glacier GX3 product is alleged to be a three-layer sheet with "durable outer layers" and a "flexible inner layer." This structure is depicted in a cross-sectional micrograph provided in the complaint (Compl. ¶48, p. 14). | ¶29, ¶48, ¶59 | col. 1:50-52 |
| wherein one or more of the outer layers A and C is a polyester or co-polyester having a flexural modulus of from about 1,000 MPa to 2,500 MPa, | Based on differential scanning calorimetry (DSC) testing, the complaint alleges the outer layers are made from Tritan™ MP100, a copolyester (Compl. ¶49-51). On information and belief, these layers are alleged to have a flexural modulus within the claimed range (Compl. ¶52, ¶59). | ¶50-52, ¶59 | col. 7:46-48 |
| the inner layer B is comprised of an elastomeric material having a hardness from about A80 to D75, and | Based on DSC testing, the inner layer is alleged to be made from Ecdel™ 9967, a polyester elastomer (Compl. ¶53-54). On information and belief, this layer is alleged to be a polyester elastomer with a hardness falling within the claimed range of A80 to D75 (Compl. ¶55, ¶59). | ¶53-55, ¶59 | col. 2:45-48 |
| the polymeric sheet composition has a flexural modulus of from about 750 MPa to 2,000 MPa. | The complaint alleges on information and belief that the overall flexural modulus of the Glacier GX3 sheet is about 1,500 MPa, which falls within the claimed range (Compl. ¶56, ¶59). | ¶56, ¶59 | col. 9:8-12 |
- Identified Points of Contention:
- Scope Questions: The infringement analysis will likely focus on the numerical ranges in Claim 1. A key question will be whether the measured physical properties (flexural modulus, hardness) of the Glacier GX3 product fall within the claimed ranges. The interpretation of the term "about" will be critical in determining the breadth of these ranges.
- Technical Questions: The complaint relies on its own testing, including optical microscopy and DSC, to identify the material composition and properties of the accused product (Compl. ¶48-50). A point of contention may be whether this testing is sufficiently accurate and whether Defendant's materials are, in fact, the specific commercial polymers (Tritan™ MP100 and Ecdel™ 9967) alleged by Plaintiff, or merely "substantially similar" materials that may not meet all claim limitations.
V. Key Claim Terms for Construction
The Term: "about"
- Context and Importance: This term qualifies every numerical range in the asserted independent claim, including the flexural modulus of the outer layers, the hardness of the inner layer, and the flexural modulus of the overall sheet. Its construction will directly impact the scope of the claims and whether test results for the accused product, which may be close but not identical to the recited values, constitute infringement.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The specification frequently uses "about" when introducing numerical ranges for material properties, suggesting the inventors did not intend for these to be strict, absolute limits ('630 Patent, col. 7:33-34, col. 8:19-21).
- Evidence for a Narrower Interpretation: A party could argue that the term should be interpreted in light of the specific examples provided in the patent. The patent includes tables with precise measured values for exemplary materials, which could be used to argue for a more constrained meaning of "about" ('630 Patent, Tables 1-3, col. 13-16).
The Term: "flexural modulus"
- Context and Importance: This physical property is a core technical limitation defining the required stiffness of both the outer layers and the overall composite sheet. The infringement case hinges on whether the accused product meets these specific modulus ranges. Practitioners may focus on this term because the specific testing protocol used to measure it could become a point of dispute.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The patent's definition section states that "flexural modulus" and "elastic modulus" are "substantially the same" for the isotropic materials at issue and that they are "generally correlated" ('630 Patent, col. 7:6-12). This could support an argument that different but related measures of stiffness satisfy the claim limitation.
- Evidence for a Narrower Interpretation: The patent also states that flexural modulus "may be measured by the test listed in ASTM D790" ('630 Patent, col. 7:13-15). A party may argue that this reference requires strict adherence to the ASTM D790 standard, and any deviation in testing methodology would fail to prove infringement of the claim limitation as written.
VI. Other Allegations
- Indirect Infringement: The complaint alleges inducement based on Defendant's "instructions for use," marketing materials, and website content that allegedly direct and encourage customers (e.g., orthodontists) to thermoform the Glacier GX3 sheets into infringing dental appliances (Compl. ¶69). Contributory infringement is alleged on the basis that the Glacier GX3 sheets are especially made for this infringing purpose and are not staple articles of commerce with substantial non-infringing uses (Compl. ¶70-73).
- Willful Infringement: Willfulness is alleged based on both pre- and post-suit knowledge. The complaint alleges pre-suit knowledge dating to "late 2018," when Defendant allegedly evaluated Plaintiff's own commercial product, and was reinforced by an August 14, 2024 notice letter (Compl. ¶66, ¶75). Continued infringement after receiving the notice letter and the filing of the complaint is alleged as further evidence of willfulness (Compl. ¶11, ¶66).
VII. Analyst’s Conclusion: Key Questions for the Case
- A central issue will be one of evidentiary proof and claim scope: Will expert testing in discovery confirm that the physical properties of the Glacier GX3 material fall within the specific numerical ranges of Claim 1? The outcome will likely depend on the court's construction of the term "about" and the accepted methodologies for measuring "flexural modulus" and "hardness."
- A key question will concern validity and litigation leverage: Given that an Inter Partes Review proceeding confirmed the patentability of most asserted claims, a significant issue will be what, if any, invalidity arguments remain available to the Defendant and how the IPR outcome will influence settlement negotiations and the court's view of the patent's strength.
- The case may also turn on a question of material identity: Beyond the physical properties, to what extent must Plaintiff prove that the accused product's constituent polymers are the specific commercial materials alleged (or their equivalents) to satisfy the "polyester or co-polyester" and "elastomeric material" limitations of the claims?