Yang v. Azotic LLC

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: Ruping Yang and Eng Kiong Ng (Minnesota)
  • Defendant: Azotic, LLC (Minnesota)
  • Plaintiff’s Counsel: Godwin Dold
• Case Identification: 0:25-cv-02813, D. Minn., 07/09/2025
• Venue Allegations: Venue is alleged to be proper in the District of Minnesota because the Defendant is subject to personal jurisdiction, directs its business in the district, and a substantial part of the events giving rise to the claim occurred there.
• Core Dispute: Plaintiffs, former employees of Defendant, seek a declaratory judgment of non-infringement and unenforceability of Defendant's patents, arguing that the subject matter publicly disclosed in the patents cannot simultaneously be protected as a trade secret.
• Technical Context: The technology at issue involves methods for applying thin film coatings to gemstones and other decorative objects to create or enhance their color and visual appearance.
• Key Procedural History: This action follows a prior state court case where Defendant sued Plaintiffs for trade secret misappropriation, which was later dismissed without prejudice. Plaintiffs allege that Defendant continues to threaten litigation, asserting that its patented technology also constitutes its trade secrets, thereby creating the immediate controversy necessary for a declaratory judgment action. The complaint notes that one of the patents at issue, U.S. Patent No. 5,853,826, expired in 2018.

Case Timeline

II. Technology and Patent(s)-in-Suit Analysis

U.S. Patent No. 7,137,275 - "Coatings for Gemstones and Other Decorative Objects," issued November 21, 2006

The Invention Explained

• Problem Addressed: The patent describes drawbacks of prior art gemstone treatments, including high-temperature diffusion methods that damage stones and interference-based coatings that produce a "dichroic appearance"—an often unnatural-looking color that changes with the viewing angle (Compl. Exhibit A, '275 Patent, col. 1:36-47; col. 2:40-46).
• The Patented Solution: The invention claims to solve this by applying a durable, sputtered coating at low temperatures that imparts a "body color that appears substantially constant at different angles of observation" ('275 Patent, Abstract). This is achieved not primarily through optical interference, but through a "high absorption layer" that absorbs specific frequencies of light passing through it, creating a consistent, non-dichroic color ('275 Patent, col. 3:22-28).
• Technical Importance: This technology sought to provide a method for creating enhanced gemstones with more natural, stable coloration, while using a low-temperature process that preserved the integrity of the underlying stone ('275 Patent, col. 2:52-56).

Key Claims at a Glance

The complaint, a declaratory judgment action, does not assert specific claims but seeks a declaration of non-infringement of any valid and enforceable claims (Compl. ¶39). The patent’s independent product claims are 1, 6, and 12.

• Independent Claim 1 includes: A gemstone with a coating born only on its pavilion that serves as an absorber to impart a "uniform body color that does not substantially change in hue when viewed at different angles"; the coating has a "thickness that is greatest adjacent the culet"; it includes a "high absorption layer" over which is deposited a layer comprising titanium or silicon.
• Independent Claim 6 includes: A similar gemstone structure, but where the layer deposited over the high absorption layer comprises carbon.
• Independent Claim 12 includes: A similar gemstone structure, but where the high absorption layer has an optical thickness of less than about 950 Å and has a layer comprising carbon deposited over it.

U.S. Patent No. 7,526,928 B1 - "Multi-color Gemstones and Gemstone Coating Deposition Technology," issued May 5, 2009

The Invention Explained

• Problem Addressed: The patent notes that natural multi-color gemstones are rare and that creating them synthetically or by bonding materials is difficult. Prior art single-color enhancement techniques could not produce a single gemstone with multiple distinct color zones (Compl. Exhibit B, '928 Patent, col. 3:1-6).
• The Patented Solution: The invention describes a gemstone with at least two different color zones created by applying coatings of different compositions to different areas of the stone's surface ('928 Patent, Abstract). A key aspect is a novel deposition technique, such as using a rotating holder and precision spray nozzles, that allows for this selective-area coating to be performed efficiently and without physical masks ('928 Patent, col. 11:1-15).
• Technical Importance: This method enabled the creation of novel multi-color gemstones that mimic rare natural stones or have unique appearances, using a scalable and precise manufacturing process ('928 Patent, col. 4:51-57).

Key Claims at a Glance

The complaint does not assert specific claims (Compl. ¶39). The patent’s independent product claims are 1, 13, and 14.

• Independent Claim 1 includes: A gemstone with a first coating on a first area of the pavilion and a second, different-composition coating on a second area, creating an "overlap area characterized by a mixture of both...coatings."
• Independent Claim 13 includes: A gemstone with a rectangular cross-section and two different coatings on opposite sides of the pavilion, creating a "dominant color" in one region, a "non-dominant color" in a second region, and a "third region that exhibits either the dominant color or a mixture."
• Independent Claim 14 includes: A gemstone with two different coatings on the pavilion, where the first coating comprises a material from a first group (e.g., gold, silicon, bismuth) and the second coating comprises a material from a second group (e.g., chromium, titanium, zirconium).

Multi-Patent Capsule: U.S. Patent No. 5,853,826

• Patent Identification: U.S. Patent No. 5,853,826, "Method of Improving the Color of Transparent Materials," issued December 29, 1998.
• Technology Synopsis: The patent discloses a method to enhance gemstone color by applying a thin film to the pavilion (back side) of the stone using a low-temperature process like sputtering, which avoids damaging the stone (Compl. Exhibit C, '826 Patent, col. 1:11-23). The coating is designed to create an optical interference effect, causing the stone's apparent color to shift when viewed from different angles ('826 Patent, Abstract).
• Asserted Claims: The complaint seeks a declaratory judgment of non-infringement of any valid claims (Compl. ¶39). Independent claims are 1 (method) and 9 (product).
• Accused Features: The declaratory judgment complaint does not identify specific accused products or processes of the Plaintiffs. It broadly relates to Plaintiffs' activities in the field of gemstone enhancement, which Defendant has allegedly threatened to litigate (Compl. ¶31, ¶33).

Multi-Patent Capsule: U.S. Patent No. 7,290,404 B2

• Patent Identification: U.S. Patent No. 7,290,404 B2, "Gemstone Material," issued November 6, 2007.
• Technology Synopsis: The patent addresses the challenge of creating simulated opals with a "play-of-color," noting that prior art methods were secretive, produced random results, and trapped undesirable air bubbles (Compl. Exhibit D, '404 Patent, col. 2:11-40). The invention is a gemstone material made by embedding a plurality of dichroic particles within a vitreous material (e.g., glass) and fusing them together, often under vacuum, to create a repeatable, bubble-free material with a uniform play-of-color effect ('404 Patent, col. 5:1-7).
• Asserted Claims: The complaint seeks a declaratory judgment of non-infringement of any valid claims (Compl. ¶39). Independent claims are 1, 20, 23, and 25 (all method claims).
• Accused Features: The complaint does not describe the specific activities of the Plaintiffs for which a declaration of non-infringement is sought (Compl. ¶31, ¶33).

III. The Accused Instrumentality

Product Identification

• The complaint is a declaratory judgment action filed by Ruping Yang and Eng Kiong Ng. The "accused instrumentality" is therefore the Plaintiffs' own products, methods, or services in the field of gemstone coating and enhancement (Compl. ¶9-10).

Functionality and Market Context

• The complaint does not provide any specific technical details, descriptions, or market context for the Plaintiffs' products or processes. The dispute is framed around the legal status of the Defendant’s intellectual property rather than a technical comparison of specific products (Compl. ¶3).

IV. Analysis of Infringement Allegations

The complaint, being a request for a declaratory judgment of non-infringement, does not contain specific infringement allegations or a claim chart mapping any of Plaintiffs' activities to the patent claims. Therefore, a claim chart summary cannot be constructed from the provided document. The central contention is a legal one regarding the enforceability of the patents as trade secrets.
No probative visual evidence provided in complaint.

• Identified Points of Contention:
  • Legal Question: The primary dispute presented is whether technology disclosed and claimed in an issued U.S. patent can subsequently be protected as a trade secret. The complaint argues that patenting constitutes a public disclosure that extinguishes any corresponding trade secret rights (Compl. ¶3, ¶27). The resolution of this legal question may be dispositive of the underlying threats that form the basis of the lawsuit.
  • Scope Question ('275 Patent): A potential point of contention for the '275 Patent is the scope of the term "substantially constant." The patent distinguishes itself from prior art "dichroic" (color-shifting) coatings. This raises the question of whether a coated gemstone that exhibits any perceptible, albeit minor, color shift when viewed from different angles falls within the scope of the claims.
  • Technical Question ('928 Patent): A potential technical question for the '928 Patent centers on the claimed "overlap area characterized by a mixture of both the first and second coatings." A dispute could arise over whether a process that creates a sharp, clean boundary between two coating zones, with minimal and incidental intermingling, meets this limitation, or if the claim requires a distinct, measurable region of blended materials.

V. Key Claim Terms for Construction

• Term: "substantially constant at different angles of observation" ('275 Patent, Claim 1)

  • Context and Importance: This term is central to the '275 Patent's asserted novelty over prior art dichroic coatings. Its construction will determine the boundary between non-infringing color-shifting stones and infringing stones with stable color.
  • Intrinsic Evidence for a Broader Interpretation: The specification does not provide a quantitative metric for "substantially constant," which may support an interpretation that allows for some minor, commercially insignificant variation in hue ('275 Patent, col. 2:54-56).
  • Intrinsic Evidence for a Narrower Interpretation: The patent's background repeatedly criticizes prior art for its "dichroic appearance" and "substantial dichroic appearance" ('275 Patent, col. 2:42-43). This context suggests "substantially constant" should be construed narrowly to mean a near-complete lack of the color-shifting effect that the patent sought to overcome.

• Term: "overlap area characterized by a mixture of both the first and second coatings" ('928 Patent, Claim 1)

  • Context and Importance: This term defines the nature of the transition between the two different color coatings. The viability of an infringement claim could depend on whether an accused process creates a region that qualifies as a "mixture."
  • Intrinsic Evidence for a Broader Interpretation: The patent describes non-masking deposition methods, such as precision spraying onto a rotating gemstone, which would inherently result in some region of overlap ('928 Patent, col. 11:1-15). This may support reading "mixture" to include any area where both coating materials are present, even if not intentionally blended.
  • Intrinsic Evidence for a Narrower Interpretation: Figure 3 explicitly labels a distinct "overlap area OA," which could suggest the claim requires a discrete, identifiable zone of intermingling, rather than merely the incidental edge effects of two adjacent but separate coatings ('928 Patent, Fig. 3).

VI. Other Allegations

• Indirect Infringement: The complaint seeks a declaratory judgment of non-infringement for "either directly or indirectly" infringing activity but does not present any specific facts related to allegations of inducement or contributory infringement (Compl. ¶39).
• Willful Infringement: Willful infringement is not alleged, as this is a declaratory judgment action brought by the potential accused infringer, not an infringement action brought by the patentee.

VII. Analyst’s Conclusion: Key Questions for the Case

• A central issue will be one of legal preemption: Does the act of securing a patent, which requires full public disclosure, extinguish a patentee's right to assert trade secret protection over the very same "methods, techniques, and processes," as alleged by the Plaintiffs? The court's answer to this question may determine the viability of the underlying dispute that prompted this action.
• A threshold question will be one of justiciability: Do the Defendant's alleged statements and actions following the dismissal of the prior state court litigation create a threat of patent infringement litigation that is sufficiently immediate and real to establish an actual controversy for a declaratory judgment, or do they relate solely to non-patent trade secret claims?
• Should the case proceed to the technical merits, a key evidentiary question for the '275 Patent will be one of functional definition: What objective, measurable criteria distinguish the claimed "substantially constant" color from the "dichroic" color-shifting effect of the prior art, and what evidence can be shown regarding the characteristics of the Plaintiffs' products?