DCT
4:20-cv-03973
US Synthetic Corp v. Zhengzhou New Asia Superhard Materials Compo
Key Events
Complaint
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: US Synthetic Corporation (Delaware)
- Defendant: Zhengzhou New Asia Superhard Materials Composite Co., Ltd. (China); International Diamond Services, Inc. (Texas)
- Plaintiff’s Counsel: Porter Hedges LLP; Finnegan, Henderson, Farabow, Garrett & Dunner, LLP
- Case Identification: 4:20-cv-03973, S.D. Tex., 11/20/2020
- Venue Allegations: Plaintiff alleges venue is proper against Zhengzhou New Asia Superhard because, as a foreign corporation, it may be sued in any judicial district where it is subject to personal jurisdiction. Venue is alleged to be proper against International Diamond Services because it is incorporated in Texas and has a regular and established place of business in the district.
- Core Dispute: Plaintiff alleges that Defendant’s polycrystalline diamond compact (PDC) products infringe three U.S. patents related to the material properties, structural configuration, and manufacturing methods of PDCs used in earth-boring applications.
- Technical Context: The technology concerns polycrystalline diamond, an extremely hard synthetic material bonded to a substrate to create cutters for drill bits used in the oil and gas industry.
- Key Procedural History: The patents-in-suit claim priority back to a 2008 patent application, indicating a long-developing technology portfolio in the field of high-pressure, high-temperature material science.
Case Timeline
| Date | Event |
|---|---|
| 2008-10-03 | Earliest Priority Date for '502, '565, and '306 Patents |
| 2013-12-31 | U.S. Patent No. 8,616,306 Issues |
| 2019-12-17 | U.S. Patent No. 10,508,502 Issues |
| 2019-12-17 | U.S. Patent No. 10,507,565 Issues |
| 2020-11-20 | Complaint Filed |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 10,508,502: “Polycrystalline Diamond Compact”
- Patent Identification: U.S. Patent No. 10,508,502, “Polycrystalline Diamond Compact,” issued December 17, 2019.
The Invention Explained
- Problem Addressed: The patent’s background section describes how residual stresses at the interface between a polycrystalline diamond (PCD) table and its cemented carbide substrate can cause premature failure of the compact, especially during cooling after manufacturing or during use under thermal stress (Compl. ¶17; ’502 Patent, col. 1:63-col. 2:9).
- The Patented Solution: The invention claims a PDC that couples specific material properties (such as high coercivity and low magnetic permeability) with a “substantially planar” interface between the diamond table and the substrate (’502 Patent, Abstract). This approach is distinct from prior art that often relied on non-planar, interlocking interfaces to improve bonding, suggesting that the enhanced diamond-to-diamond bonding achieved through the claimed material properties makes such complex mechanical interfaces unnecessary (’502 Patent, col. 2:9-15, col. 4:51-59).
- Technical Importance: The invention proposes a method to enhance the durability of PDCs while potentially simplifying the manufacturing process by enabling the use of less complex, planar substrate geometries.
Key Claims at a Glance
- The complaint asserts independent claim 1 and dependent claims 2, 4, and 9-11 (Compl. ¶24).
- Independent Claim 1 requires:
- A polycrystalline diamond compact with a polycrystalline diamond table and a substrate.
- The diamond table includes diamond grains (average size ≤ 50 µm) bonded together, defining interstitial regions occupied by a catalyst.
- The unleached portion of the table exhibits a coercivity of about 115 Oe to 250 Oe.
- The unleached portion of the table exhibits a specific permeability less than about 0.10 G-cm³/g-Oe.
- The substrate is bonded to the diamond table along an interfacial surface with a “substantially planar topography.”
- The diamond table has a lateral dimension of about 0.8 cm to 1.9 cm.
U.S. Patent No. 10,507,565: “Polycrystalline Diamond, Polycrystalline Diamond Compacts, Methods of Making Same, and Applications”
- Patent Identification: U.S. Patent No. 10,507,565, “Polycrystalline Diamond, Polycrystalline Diamond Compacts, Methods of Making Same, and Applications,” issued December 17, 2019.
The Invention Explained
- Problem Addressed: The patent describes the problem of thermal degradation in PDCs caused by the presence of the metal-solvent catalyst within the diamond matrix. At high temperatures, the catalyst can cause the diamond to convert back to graphite, degrading the mechanical properties of the cutter (’565 Patent, col. 2:1-12). Conventional solutions, such as acid leaching to remove the catalyst, can be time-consuming and may weaken the PDC (’565 Patent, col. 2:13-19).
- The Patented Solution: The patent discloses a PDC formed under very high pressure (at least about 7.5 GPa) that exhibits enhanced diamond-to-diamond bonding. This results in an unleached PCD with specific material properties, including low average electrical conductivity (less than 1200 S/m) and high wear resistance (a Gratio of at least 4.0x10⁶), which indicate improved thermal stability without requiring a leaching step (’565 Patent, Abstract; col. 4:35-56).
- Technical Importance: The invention claims to produce a more thermally stable and wear-resistant PDC directly from the manufacturing process, avoiding a separate, potentially detrimental, catalyst removal step.
Key Claims at a Glance
- The complaint asserts independent claim 1 and dependent claims 2, 4, 6, 8-10, 14, and 15 (Compl. ¶24).
- Independent Claim 1 requires:
- A polycrystalline diamond compact with a diamond table and a substrate.
- The unleached portion of the table includes diamond grains (average size ≤ 50 µm) bonded together, with a catalyst in the interstitial regions.
- The unleached portion exhibits a coercivity of about 115 Oe or more.
- The unleached portion exhibits an average electrical conductivity of less than about 1200 S/m.
- The unleached portion exhibits a Gratio of at least about 4.0x10⁶.
U.S. Patent No. 8,616,306: “Polycrystalline Diamond, Polycrystalline Diamond Compacts, Methods of Fabricating Same, and Various Applications”
- Patent Identification: U.S. Patent No. 8,616,306, “Polycrystalline Diamond, Polycrystalline Diamond Compacts, Methods of Fabricating Same, and Various Applications,” issued December 31, 2013.
- Technology Synopsis: This patent addresses the management of stress and durability in PDCs by claiming a layered structure for the polycrystalline diamond table (’306 Patent, Abstract). The invention describes a first diamond layer bonded to the substrate and a second diamond layer with a different, specifically smaller, average grain size, a configuration intended to improve performance and resistance to failure (’306 Patent, col. 10:35-47).
- Asserted Claims: The complaint asserts independent claim 15 and dependent claims 20 and 21 (Compl. ¶24).
- Accused Features: The complaint alleges that the accused Dragon 2 PDC product embodies this layered structure, specifically containing a first polycrystalline diamond layer bonded to the substrate and a second layer with an average diamond grain size that is less than that of the first layer (Compl. ¶38, p. 16).
III. The Accused Instrumentality
- Product Identification: The accused product is identified as the “Dragon 2 PDC product” sold by Defendants (Compl. ¶24). The complaint provides images depicting these products as cylindrical cutters designed to be integrated into larger drill bits (Compl. ¶16, p. 4).
- Functionality and Market Context: The accused products are polycrystalline diamond compacts used as cutting elements in earth-boring applications, particularly for the oil and gas industry (Compl. ¶¶17, 23). The complaint alleges Defendants market and sell these products throughout the United States, with co-defendant International Diamond Services, Inc. acting as a US distributor providing local inventory and services in Houston, Texas (Compl. ¶¶6, 8, 12).
IV. Analysis of Infringement Allegations
'502 Patent Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| A polycrystalline diamond compact, comprising: | The accused Dragon 2 cutter is a polycrystalline diamond compact. | ¶28, p. 7 | col. 4:51-53 |
| a polycrystalline diamond table, at least an unleached portion of the polycrystalline diamond table including: | The accused Dragon 2 cutter includes a polycrystalline diamond table with at least an unleached region containing cobalt. | ¶28, p. 7 | col. 4:51-53 |
| a plurality of diamond grains bonded together via diamond-to-diamond bonding to define interstitial regions, the plurality of diamond grains exhibiting an average grain size of about 50 µm or less; and | The accused Dragon 2 cutter contains a plurality of diamond grains with an EBSD average grain size measured at 4.13 µm. An EBSD image shows the grain structure of an exemplary cutter (Compl. ¶28, p. 8). | ¶28, p. 8 | col. 5:7-14 |
| a catalyst occupying at least a portion of the interstitial regions; | Testing of the accused Dragon 2 cutter shows the presence of a cobalt catalyst in the interstitial regions. | ¶28, p. 8 | col. 5:1-6 |
| wherein the unleached portion of the polycrystalline diamond table exhibits a coercivity of about 115 Oe to about 250 Oe; | The unleached portion of the accused Dragon 2 cutter's diamond table exhibits a measured coercivity of 161.7 Oe. | ¶28, p. 8 | col. 5:37-43 |
| wherein the unleached portion of the polycrystalline diamond table exhibits a specific permeability less than about 0.10 G·cm³/g·Oe; and | The unleached portion of the accused Dragon 2 cutter's diamond table exhibits a measured specific permeability of 0.088 G·cm³/(g·Oe). | ¶28, p. 9 | col. 6:28-31 |
| a substrate bonded to the polycrystalline diamond table along an interfacial surface, the interfacial surface exhibiting a substantially planar topography; | A substrate is bonded to the diamond table, and the interfacial surface is alleged to exhibit a substantially planar topography, with a calculated ratio of planar to actual surface area of 0.7495. | ¶28, p. 9 | col. 2:49-54 |
| wherein a lateral dimension of the polycrystalline diamond table is about 0.8 cm to about 1.9 cm. | An exemplary cutter exhibits a measured lateral dimension of 1.59 cm. | ¶28, p. 9 | col. 14:30-33 |
- Identified Points of Contention:
- Scope Questions: A central issue may be the construction of "substantially planar topography." The complaint provides a quantitative measure (a surface area ratio of 0.7495), raising the question of whether this term of degree has a specific, measurable scope that the accused product meets.
- Technical Questions: The infringement case for several elements rests on specific numerical values (coercivity, permeability, grain size) obtained through Plaintiff's testing. The validity of these allegations will depend on the methodology, accuracy, and reproducibility of the tests performed on the accused product.
'565 Patent Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| A polycrystalline diamond compact, comprising: | The accused Dragon 2 product is a polycrystalline diamond compact. | ¶33, p. 11 | col. 4:39-41 |
| a polycrystalline diamond table, at least an unleached portion of the polycrystalline diamond table including: | The accused Dragon 2 cutter includes a polycrystalline diamond table with an unleached region containing cobalt. | ¶33, p. 11 | col. 4:39-41 |
| a plurality of diamond grains directly bonded together via diamond-to-diamond bonding to define interstitial regions, the plurality of diamond grains exhibiting an average grain size of about 50 µm or less; | The accused Dragon 2 cutter has diamond grains with an EBSD average grain size measured at 3.47 µm. | ¶33, p. 12 | col. 5:7-14 |
| a catalyst occupying at least a portion of the interstitial regions; | Testing of the accused cutter shows the presence of a cobalt catalyst in the interstitial regions. | ¶33, p. 12 | col. 5:1-6 |
| wherein the unleached portion of the polycrystalline diamond table exhibits a coercivity of about 115 Oe or more; | The unleached portion of the accused cutter's diamond table exhibits a measured coercivity of 171.9 Oe. | ¶33, p. 12 | col. 5:37-43 |
| wherein the unleached portion of the polycrystalline diamond table exhibits an average electrical conductivity of less than about 1200 S/m; and | The unleached portion of the accused cutter's diamond table exhibits a measured average electrical conductivity of 564 S/m. | ¶33, p. 13 | col. 2:36-38 |
| wherein the unleached portion of the polycrystalline diamond table exhibits a Gratio of at least about 4.0×10⁶; and | The unleached portion of the accused cutter's diamond table exhibits a measured G-ratio of 1.05E7. The complaint includes an image of the cutter after the wet VTL test used for this measurement (Compl. ¶33, p. 13). | ¶33, p. 13 | col. 7:1-13 |
| a substrate bonded to the polycrystalline diamond table. | The accused cutter includes a substrate bonded to the polycrystalline diamond table. | ¶33, p. 14 | col. 4:39-41 |
- Identified Points of Contention:
- Scope Questions: "Gratio" is a term defined by the patentee with reference to a specific type of wear test (a "vertical turret lathe ('VTL') test"). A key question will be whether the testing protocol used by Plaintiff on the accused product conforms to the parameters and conditions set forth in the patent's definition of the term.
- Technical Questions: What evidence does the complaint provide that the accused product's measured electrical conductivity is an "average" value representative of the bulk material, as required by the claim, and not a localized measurement? The complaint provides images showing conductivity maps across different depths of the cutter (Compl. ¶33, p. 13).
V. Key Claim Terms for Construction
The Term: "substantially planar topography" ('502 Patent, Claim 1)
Context and Importance: This term is critical because the patent distinguishes itself from prior art that used non-planar, interlocking interfaces. The scope of "substantially" will define the boundary between the patented invention and that prior art. Practitioners may focus on this term because the complaint's attempt to quantify it with a surface area ratio (0.7495) suggests that the parties' dispute may center on a measurable, numerical threshold.
Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The specification itself provides a quantitative floor, stating that a ratio of the planar surface area to the actual surface area "is greater than about 0.600" ('502 Patent, col. 2:50-56). This language may support an interpretation that is not perfectly flat but falls within a defined range of planarity.
- Evidence for a Narrower Interpretation: The figures in the patent, such as FIG. 3A, depict a perfectly flat interface between the PCD table and the substrate (’502 Patent, Fig. 3A). An argument could be made that these embodiments limit the term to interfaces that are visually or geometrically flat, without significant texturing.
The Term: "Gratio" ('565 Patent, Claim 1)
Context and Importance: This is a patentee-defined term for wear resistance. As an unconventional term, its meaning is controlled entirely by the patent's specification. Infringement of this element will depend on a factual comparison of the test method used on the accused product against the specific definition provided in the patent.
Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The patent defines the term as "the ratio of the volume of workpiece cut to the volume of PCD worn away during a cutting process, such as in a vertical turret lathe ('VTL') test" ('565 Patent, col. 7:1-5). This provides a general formula.
- Evidence for a Narrower Interpretation: The patent immediately follows the general definition with a specific, detailed "example of suitable parameters" for the test, including depth of cut, back rake angle, in-feed, rotary speed, and workpiece material and dimensions (’565 Patent, col. 7:5-13). A defendant may argue that these parameters are not merely exemplary but are integral to the definition, limiting the claim to performance under these specific conditions.
VI. Other Allegations
- Indirect Infringement: The complaint alleges both induced and contributory infringement for all three patents. It asserts that Defendants encourage infringement through "descriptions on their websites and related materials" and by selling the accused products to customers with the specific intent that they be used in an infringing manner. It further alleges the products are material parts of the patented inventions with no substantial non-infringing uses (Compl. ¶¶29, 34, 39).
- Willful Infringement: The complaint does not contain an explicit allegation of willful infringement. However, it states that Defendants "will have had knowledge of the ['502/ '565/ '306] Patent and the infringing nature of its Accused Products at least as of the date of service of this Complaint," which may form the basis for alleging post-suit willfulness (Compl. ¶¶29, 34, 39). No facts are alleged to support pre-suit knowledge of the patents.
VII. Analyst’s Conclusion: Key Questions for the Case
- A core issue will be one of measurement and methodology: The infringement allegations for all three patents rely heavily on specific quantitative measurements of material properties (e.g., coercivity, electrical conductivity, permeability, Gratio). The case may turn on the factual question of whether the testing protocols used by the Plaintiff to analyze the accused products are scientifically valid and consistent with the definitions and standards set forth in the patents.
- A key question of claim construction will be the definitional scope of "substantially planar topography." The court's interpretation—whether it is a qualitative term of degree or can be defined by the quantitative surface-area ratio disclosed in the specification—will be critical to determining infringement of the '502 patent.
- A central evidentiary question for the '306 patent will be one of physical structure. The dispute will likely focus on factual evidence from materials analysis, such as the scanning electron microscopy image provided in the complaint, to determine if the accused product possesses the claimed two-layer diamond table with different average grain sizes (Compl. p. 16).