Caihong Display Devices Co., Ltd. v. Corning Incorporated

Caihong Display Devices Co., Ltd. v. Corning Incorporated is an inter partes review (IPR) proceeding, IPR2025-00439, before the Patent Trial and Appeal Board (PTAB) concerning U.S. Patent 7,851,394. Caihong Display Devices Co., Ltd. is a China-based manufacturer and distributor of display components, including liquid crystal display (LCD) panels and substrate glass. Corning Incorporated is a leading American multinational technology company specializing in materials science, particularly in glass, ceramics, and optical physics, with a significant business segment dedicated to display technologies, manufacturing glass substrates for flat panel displays. Neither party is identified as a non-practicing entity (NPE) or patent assertion entity (PAE); rather, they are direct competitors in the global display glass market.

The patent at issue, U.S. Patent 7,851,394, is titled "Alkali-Free Boroaluminosilicate Glass" and describes specific alkali-free boroaluminosilicate glass compositions. These compositions are designed for use as substrates in flat panel display devices, aiming to achieve desirable physical and chemical properties such as low thermal expansion, high liquidus viscosity, high strain point, and low density through a refined glass composition and fining process. While the specific accused product is not detailed in the IPR docket itself, the dispute is part of a broader competitive landscape. Corning has accused Caihong's "616 glass" and "615 glass," used in LCD panels, of infringement in a parallel investigation at the U.S. International Trade Commission (ITC), Investigation No. 337-TA-1441, indicating these glass products are the allegedly infringing technology.

This IPR is currently at a "Not Instituted - Procedural" status at the PTAB, a specialized administrative court within the U.S. Patent and Trademark Office. The procedural posture is particularly notable due to ongoing discussions and rulings concerning the petitioner's expert declaration. Caihong sought to replace its initial expert, and issues arose when the substitute declaration was found to have substantive changes beyond mere biographical updates, leading to a motion from Corning to strike portions of the new declaration. The PTAB's handling of this procedural issue is critical as it can impact whether the IPR proceeds to a merits-based institution decision. The case is further notable due to its direct linkage with a parallel ITC investigation initiated by Corning, which underscores the high-stakes competitor-versus-competitor nature of the dispute within the global LCD market. The PTAB's evolving discretionary denial policies, particularly the Fintiv factors, are highly relevant in cases with co-pending litigation, as the Board evaluates factors like the proximity of trial dates and the overlap of issues. In fact, Caihong has also filed other IPRs against Corning on related display glass patents (e.g., IPR2025-00937 on US Patent 8,640,498 and IPR2025-01040 on US Patent 9,512,025), further emphasizing the competitive intensity and the strategic use of PTAB proceedings in this industry.

The case "Caihong Display Devices Co., Ltd. v. Corning Incorporated," IPR2025-00439, is an inter partes review (IPR) proceeding before the Patent Trial and Appeal Board (PTAB) concerning US Patent 7,851,394, not a district court patent infringement litigation. Therefore, typical litigation milestones such as complaints, answers, counterclaims, Markman hearings, discovery, trial, and jury verdicts do not directly apply to this PTAB proceeding. However, related patent infringement allegations have occurred in parallel proceedings.

Here is a chronological overview of the key legal developments and outcomes related to US Patent 7,851,394, including the IPR and parallel proceedings:

PTAB Inter Partes Review (IPR2025-00439):

• 2025-01-12: Caihong Display Devices Co., Ltd. filed a petition for inter partes review (IPR) against Corning Incorporated, challenging claims 1-16 of U.S. Patent No. 7,851,394. The petition primarily alleged that the challenged claims were unpatentable as obvious over the combination of prior art references Miwa and Bange under 35 U.S.C. §103.
• 2025-04-04: Patent Owner Corning Incorporated filed a motion to strike certain paragraphs of the Declaration of Prof. Frank Ernst, an expert for Caihong, arguing they were untimely and contravened the Board's instructions. Caihong had filed a substitute declaration from Prof. Ernst on the same date. Corning contended that the substitute declaration included substantive changes rather than merely biographical information. Corning's expert, Dr. Richard Brow, also provided a declaration disputing Prof. Ernst's definition of a person of ordinary skill in the art.
• Current Posture: The IPR's status is "Not Instituted - Procedural." This indicates that the PTAB declined to institute the review, likely due to the procedural issues surrounding the petitioner's expert declaration rather than on the merits of patentability.

Parallel Proceedings:

• 2025-01-31 (Complaint Filed) / 2025-02-03 (Supplemented): Corning Incorporated filed a complaint with the U.S. International Trade Commission (ITC) under Section 337 of the Tariff Act of 1930. The complaint accused Caihong Display Devices Co., Ltd. and several other display manufacturers (including Hisense USA Corporation, HKC Corporation Ltd., LG Electronics U.S.A., Inc., TCL China Star Optoelectronics Technology Co., Ltd., TTE Technology, Inc., VIZIO, Inc., and Xianyang Caihong Optoelectronics Technology Co., Ltd.) of infringing US Patent Nos. 7,851,394, 8,642,491, and 8,640,498, related to glass substrates for liquid crystal displays.
• 2025-03-07: The ITC instituted an investigation into the complaint, designated as Case No. 337-TA-1441.
• 2025-04-24: Corning Incorporated filed a miscellaneous action, Case No. 1:2025mc00049, in the U.S. District Court for the District of Columbia, seeking the issuance of Letters Rogatory. This was likely in support of the ITC investigation.
• 2025-06-10: The U.S. District Court for the District of Columbia granted Corning's motion for the issuance of Letters Rogatory and directed the Clerk to close the case upon issuance.
• 2026-04-02: U.S. Patent No. 7,851,394 was undergoing an Ex Parte Reexamination proceeding, with a status of "Reexam Assigned to Examiner for Determination."
• 2026-04-08: In the ITC investigation (337-TA-1441), Administrative Law Judge Bryan Moore issued an initial determination, finding that Caihong's "616 glass" product did not infringe Corning's patents.
• 2026-04-24: Cooley LLP, counsel for Caihong, announced that Corning Incorporated would not petition the ALJ's initial determination to the full ITC. This action made the non-infringement finding for the 616 glass effectively final in the ITC investigation, marking a "decisive victory" for Caihong and allowing its customers to continue importing and selling televisions containing that glass.

Counsel of Record for Caihong Display Devices Co., Ltd. in IPR2025-00439

Caihong Display Devices Co., Ltd., the petitioner in IPR2025-00439, is represented by attorneys from Merchant & Gould PC.

The counsel of record for Caihong includes:

• Daniel Pereira

  • Role: Petitioner Counsel
  • Firm: Merchant & Gould PC. The firm is listed with an email address, dpereira@merchantgould.com, suggesting an office location within the firm's network.
  • Relevant Experience: Daniel Pereira is a partner at Merchant & Gould. His practice focuses on patent prosecution, intellectual property litigation, and post-grant proceedings before the PTAB. He has experience representing both petitioners and patent owners in inter partes review (IPR) proceedings.

• Donald McPhail

  • Role: Petitioner Counsel
  • Firm: Merchant & Gould PC. The firm is listed with an email address, dmcphail@merchantgould.com, suggesting an office location within the firm's network.
  • Relevant Experience: Donald McPhail is an attorney at Merchant & Gould with a focus on intellectual property law, including patent litigation and post-grant proceedings. He represents clients in various technology sectors.

The provided information does not specify the particular office location of Merchant & Gould PC for these attorneys within the search results, but indicates their representation in this PTAB proceeding. The IPR was ultimately denied institution on discretionary grounds.

The counsel of record representing Corning Incorporated in IPR2025-00439 includes:

• Jason D. Eisenberg
  • Role: Respondent Counsel (indicated as "et al." meaning he is likely part of a team, potentially lead counsel given his extensive experience)
  • Firm: Sterne, Kessler, Goldstein & Fox P.L.L.C., Washington, D.C.
  • Experience: Mr. Eisenberg is a Director in Sterne Kessler's Electronics Practice Group and Chair of the firm's Reexamination, Supplemental Examination, and Reissue Practice. He has substantial experience with the Patent Trial and Appeal Board (PTAB), having been involved in approximately 300 inter partes and post-grant reviews, 150 reexaminations, and 20 Federal Circuit cases. He is also a recognized author and editor in the field of patent office litigation and has been ranked among the top-performing attorneys before the PTAB for patent owners.

While Jason D. Eisenberg is identified as counsel for Corning Incorporated, the available public search results indicate "et al.", suggesting other attorneys are involved but were not specifically named in the provided snippets. A complete list of all counsel, including their specific roles (e.g., local counsel, in-house), is not explicitly available through the conducted web searches for this specific PTAB case.