PRIVILEGED AND CONFIDENTIAL — ATTORNEY WORK PRODUCT
This document has been prepared by Calderwood & Harkness LLP in connection with the above-captioned litigation and constitutes attorney work product. This document is protected from disclosure by the attorney work product doctrine, the attorney-client privilege, and all other applicable privileges and protections. This document shall not be disclosed to any person or entity other than authorized counsel for Plaintiff Optiwave Semiconductor Corp. and authorized personnel working under the direction of such counsel without the prior written consent of Calderwood & Harkness LLP.
UNITED STATES DISTRICT COURT EASTERN DISTRICT OF TEXAS MARSHALL DIVISION
OPTIWAVE SEMICONDUCTOR CORP., Plaintiff,
v.
LUMICORE TECHNOLOGIES, INC., Defendant.
Case No. 2:24-cv-00319-JRG
Before the Honorable Judge James R. Gilstrap
INFRINGEMENT CLAIM CHART
U.S. Patent No. 10,234,847 ("the '847 Patent")
Asserted Claims: 1, 3, 5, 9, and 14
Date Served: September 16, 2024
Served Pursuant to: P.R. 3-1 Infringement Contentions, Patent Rules of the Eastern District of Texas
Prepared by: Calderwood & Harkness LLP 350 South Grand Avenue, 48th Floor Los Angeles, California 90071 Telephone: (213) 555-8200 Facsimile: (213) 555-8201
Counsel for Plaintiff Optiwave Semiconductor Corp.:
Alan Ngo — Responsible Partner Marcus Delgado — Billing Partner Wendy Schultz — Lead Associate Omar Siddiqui — Working Associate
Local Counsel for Plaintiff Optiwave Semiconductor Corp.:
James "Jim" Callahan Whitmore & Callahan LLP 110 North College Avenue, Suite 800 Tyler, Texas 75702 Telephone: (903) 555-4400 Facsimile: (903) 555-4401
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I. INTRODUCTION AND IDENTIFICATION OF THE ASSERTED PATENT
A. Patent Identification
Plaintiff Optiwave Semiconductor Corp. ("OWS" or "Plaintiff") hereby serves these Infringement Contentions pursuant to P.R. 3-1 of the Patent Rules of the Eastern District of Texas, identifying with particularity each claim of the asserted patent that is alleged to be infringed by each accused instrumentality, and the specific evidence supporting each allegation of infringement on a limitation-by-limitation basis.
The patent asserted in this claim chart is United States Patent No. 10,234,847 ("the '847 Patent"), entitled "Multi-Channel Silicon Photonic Waveguide Multiplexer with Low Insertion Loss." The '847 Patent was filed on September 14, 2016, and issued on March 19, 2019, from United States Patent Application Serial No. 15/265,418. The '847 Patent was originally assigned to Optiwave Semiconductor Corp., and OWS remains the current assignee. No change in assignment has occurred since the date of issuance. A true and correct copy of the '847 Patent is attached hereto as Exhibit A.
The '847 Patent is a member of a patent family that includes United States Patent No. 9,678,562 ("the '562 Patent"), which is also asserted in this action. The '847 Patent is a continuation of the application that issued as the '562 Patent, sharing a common specification and priority date. The prosecution histories of both patents in this family are relevant to the construction of the claims asserted herein.
All maintenance fees for the '847 Patent are current as of the date of this filing. The '847 Patent is in full force and effect and has not been the subject of any reexamination, inter partes review, post-grant review, or other post-issuance proceeding before the United States Patent and Trademark Office.
B. Technology Overview
The '847 Patent is directed to a multi-channel silicon photonic waveguide multiplexer architecture designed to combine multiple optical signals of different wavelengths onto a single waveguide while achieving low insertion loss. The invention described and claimed in the '847 Patent addresses critical challenges in the field of silicon photonics for data-center interconnect applications—specifically, the need to multiplex dense wavelength-division multiplexed ("DWDM") signals on a single photonic integrated circuit ("PIC") with minimal signal degradation.
As the telecommunications and data-center industries have demanded ever-higher bandwidth and data throughput, silicon photonics has emerged as a leading technology for enabling high-speed optical interconnects. A core challenge in silicon photonic transceiver design is the efficient combination (multiplexing) of multiple wavelength channels onto a single output waveguide, while maintaining sufficiently low insertion loss to preserve signal integrity across long-haul and short-reach transmission links. Prior-art multiplexer designs suffered from excessive insertion loss, particularly as channel counts increased, resulting in degraded signal-to-noise ratios, increased power consumption for optical amplification, and reduced overall system performance.
The '847 Patent discloses and claims a novel waveguide multiplexer structure that achieves substantially lower insertion loss than prior-art designs through a combination of structural innovations, including optimized waveguide geometry, tapered waveguide transitions, and specific coupler configurations. These innovations enable the multiplexer to combine multiple wavelength channels with minimal power penalty, making it suitable for deployment in next-generation 400G, 800G, and beyond transceiver modules for data-center and telecommunications applications.
The patented waveguide multiplexer structure is a core component of OWS's commercially successful OWS-400ZR and OWS-800XR transceiver module product families. OWS has invested substantial resources in the research, development, and commercialization of the technology claimed in the '847 Patent, and the patented technology represents a significant competitive advantage for OWS in the silicon photonics transceiver market.
C. Asserted Claims
OWS asserts Claims 1, 3, 5, 9, and 14 of the '847 Patent against the accused products identified in Section II below. The asserted claims are summarized as follows:
Claim 1 is an independent claim directed to a multi-channel silicon photonic waveguide multiplexer apparatus comprising, inter alia, a silicon substrate with a plurality of input waveguides, a waveguide multiplexer structure optically coupled to the input waveguides and configured to combine optical signals onto a single output waveguide, and structural features achieving low insertion loss.
Claim 3 is a dependent claim that depends from Claim 1 and adds specific structural features to the multiplexer apparatus, thereby narrowing the scope of independent Claim 1 by requiring additional structural elements not recited in the independent claim.
Claim 5 is a dependent claim that depends from Claim 1 and adds specific performance or design parameters to the multiplexer apparatus, further narrowing the scope of independent Claim 1 by imposing additional requirements related to the operational characteristics or physical configuration of the multiplexer.
Claim 9 is an independent claim that may be directed to a method or apparatus for multiplexing optical signals using a silicon photonic waveguide structure. Calderwood & Harkness LLP's internal analysis, dated October 5, 2024, has identified one limitation in Claim 9 as potentially constituting a means-plus-function limitation subject to 35 U.S.C. § 112(f). The corresponding structure for this means-plus-function element has been identified in the specification of the '847 Patent and is mapped in detail in Section VIII below.
Claim 14 is a dependent claim that depends from Claim 9 and adds an additional limitation to the independent claim, requiring a further structural or functional feature beyond those recited in Claim 9.
All claims of the '847 Patent are asserted on a literal infringement basis only. OWS does not assert infringement of any claim of the '847 Patent under the doctrine of equivalents. Doctrine of equivalents contentions are reserved for certain claims of the '193 Patent and the '015 Patent, as set forth in the separate claim charts filed for those patents.
II. IDENTIFICATION OF ACCUSED PRODUCTS
A. LumiLink 400G-ZR+
The LumiLink 400G-ZR+ is a 400-gigabit coherent optical transceiver module manufactured, used, sold, offered for sale, and/or imported into the United States by Defendant Lumicore Technologies, Inc. ("Lumicore"). Lumicore is a Delaware corporation with its principal place of business at 9200 Spectrum Boulevard, Building C, Austin, Texas 78759. Lumicore maintains a sales office and technical support center within this judicial district at 2700 Earl Campbell Parkway, Suite 150, Tyler, Texas 75701.
The LumiLink 400G-ZR+ was commercially launched in the third quarter of 2022 and has since been widely sold to customers throughout the United States, including customers with facilities located in the Eastern District of Texas. According to Lumicore's public financial filings and segment disclosures, the LumiLink 400G-ZR+ generated approximately $94.8 million in revenue during fiscal year 2023.
The LumiLink 400G-ZR+ is accused of infringing Claims 1, 3, 5, 9, and 14 of the '847 Patent. The LumiLink 400G-ZR+ is also accused of infringing claims of the '193 Patent and the '562 Patent, as set forth in separate claim charts filed concurrently herewith.
OWS retained Benchmark Semiconductor Analysis, LLC ("Benchmark"), an independent semiconductor teardown and reverse-engineering firm located at 2244 Mission College Boulevard, Santa Clara, California 95054, to conduct a comprehensive teardown and reverse-engineering analysis of the LumiLink 400G-ZR+ transceiver module. The teardown was conducted under the direction of Kevin Ng, Lead Engineer at Benchmark, and the resulting teardown report was delivered on December 12, 2022. The Benchmark teardown report confirms the presence of the accused waveguide multiplexer structures on the silicon photonic integrated circuit die within the LumiLink 400G-ZR+ module, and provides die-level photographs, scanning electron microscope ("SEM") images, and cross-sectional analyses that identify and map each structural feature corresponding to the asserted claim limitations of the '847 Patent.
The LumiLink 400G-ZR+ has been sold to customers with facilities in the Eastern District of Texas, including but not limited to: Pinnacle Data Systems, LLC, located in Longview, Texas; Frontier Cloud Services, Inc., located in marshall, Texas; and CrossPoint Networking Corp., with operations in Plano, Texas (transferred to the Tyler Division for case management purposes). Evidence of these sales within the district has been obtained through discovery and will be presented at trial.
B. LumiLink 800G-DR8
The LumiLink 800G-DR8 is an 800-gigabit parallel single-mode optical transceiver module manufactured, used, sold, offered for sale, and/or imported into the United States by Lumicore Technologies, Inc. The LumiLink 800G-DR8 was commercially launched in the first quarter of 2023. According to Lumicore's public financial filings and segment disclosures, the LumiLink 800G-DR8 generated approximately $128.4 million in revenue during fiscal year 2023, making it Lumicore's highest-revenue transceiver product in the accused product line.
The LumiLink 800G-DR8 is accused of infringing Claims 1, 3, 5, 9, and 14 of the '847 Patent. The LumiLink 800G-DR8 is also accused of infringing claims of the '193 Patent, the '562 Patent, and the '015 Patent, as set forth in separate claim charts filed concurrently herewith.
Benchmark Semiconductor Analysis, LLC conducted a follow-on teardown and reverse-engineering analysis of the LumiLink 800G-DR8 transceiver module under the direction of Kevin Ng, with the teardown report completed in June 2023. The Benchmark teardown report for the LumiLink 800G-DR8 confirms the presence of accused waveguide multiplexer structures on the silicon photonic integrated circuit die, and provides die-level photographs, SEM images, and cross-sectional analyses substantially consistent with—and in many respects identical to—the structures identified in the LumiLink 400G-ZR+ teardown.
The LumiLink 800G-DR8 has been sold to customers with facilities in the Eastern District of Texas, as confirmed through sales records and customer testimony obtained in discovery.
C. Note Regarding LumiEdge 1600G-LR
For the avoidance of doubt, the LumiEdge 1600G-LR transceiver module (launched in the fourth quarter of 2023, with fiscal year 2023 revenue of approximately $41.7 million) is not accused of infringing any claim of the '847 Patent. The LumiEdge 1600G-LR is accused of infringing only certain claims of the '193 Patent and the '015 Patent, as set forth in separate claim charts filed for those patents. This claim chart does not address the LumiEdge 1600G-LR product in any respect.
III. SOURCES OF EVIDENCE
The infringement contentions set forth in this claim chart are supported by the following categories of evidence, which OWS has obtained through its own investigation, through the discovery process in this action, and through publicly available sources. OWS reserves the right to rely on additional evidence as it becomes available through ongoing discovery.
A. Benchmark Teardown Reports
OWS retained Benchmark Semiconductor Analysis, LLC to conduct independent teardown and reverse-engineering analyses of the accused products. The Benchmark teardown reports constitute primary evidence of the structural and functional characteristics of the accused products' silicon photonic integrated circuits, including the waveguide multiplexer structures at issue in this claim chart.
LumiLink 400G-ZR+ Teardown Report: Benchmark prepared a comprehensive teardown report for the LumiLink 400G-ZR+ transceiver module, dated December 12, 2022. The teardown was conducted at Benchmark's facility at 2244 Mission College Boulevard, Santa Clara, California 95054, under the direction of Kevin Ng, Lead Engineer. The report includes die-level optical and electron microscopy photographs of the silicon photonic integrated circuit; scanning electron microscope ("SEM") images of waveguide cross-sections, coupler regions, and input/output port configurations; cross-sectional analyses of the photonic integrated circuit layers; and detailed identification and annotation of waveguide multiplexer structures, slab couplers, waveguide arrays, tapered transitions, and input/output port configurations. Chain of custody for the LumiLink 400G-ZR+ sample was maintained and documented by Benchmark throughout the teardown process.
LumiLink 800G-DR8 Teardown Report: Benchmark prepared a follow-on teardown report for the LumiLink 800G-DR8 transceiver module, completed in June 2023. This report follows the same methodology and includes the same categories of analytical data as the LumiLink 400G-ZR+ report, with specific attention to the eight-channel waveguide multiplexer structure on the 800G-DR8 PIC die. Chain of custody for the LumiLink 800G-DR8 sample was similarly maintained and documented.
Both Benchmark teardown reports include high-resolution annotated photographs with callouts to specific structural features corresponding to the asserted claim limitations of the '847 Patent. Annotated versions of key teardown photographs are included in Appendix 4 to this claim chart.
B. Lumicore Design Documents Produced in discovery
Through the discovery process in this action, Lumicore has produced approximately 147,000 documents comprising approximately 980,000 pages. These productions include, inter alia, engineering specifications, CAD and layout files, product data sheets, internal test reports, design review presentations, fabrication run data, and other technical documents relating to the LumiLink 400G-ZR+ and LumiLink 800G-DR8 transceiver modules.
Certain documents produced by Lumicore have been designated under the three-tier stipulated protective order entered in this case (Dkt. No. 47) as "Confidential," "Highly Confidential — Attorneys' Eyes Only" ("AEO"), or "Highly Confidential — Source Code." Where this claim chart references documents bearing AEO or Source Code designations, such references are made in a manner consistent with the terms of the protective order, and the underlying documents are available for review only by authorized individuals as defined in the protective order.
The Lumicore design documents produced in discovery provide direct evidence of the internal architecture and design parameters of the accused waveguide multiplexer structures, including waveguide dimensions, coupler geometries, materials specifications, insertion loss targets and measured performance data, and design rationale for specific structural features. These documents corroborate and supplement the physical evidence obtained through the Benchmark teardown analyses.
C. Deposition Testimony
OWS has obtained deposition testimony from key witnesses that supports the infringement contentions set forth in this claim chart. The depositions taken to date that are relevant to the '847 Patent claim chart include the following:
Deposition of Dr. Sandra Michaud (Lumicore Chief Technology Officer), November 19, 2024: Dr. Michaud is the Chief Technology Officer of Lumicore Technologies, Inc. and was directly involved in the design and development of the LumiLink product line, including the LumiLink 400G-ZR+ and LumiLink 800G-DR8 transceiver modules. During her deposition, Dr. Michaud admitted that she and members of her engineering team reviewed OWS's published patent applications during the design phase of the LumiLink product line. Dr. Michaud further testified that she could not identify specific non-infringing design alternatives for the waveguide multiplexer architecture employed in the accused products. Specific page and line citations to Dr. Michaud's deposition testimony are set forth in the claim charts below and in Appendix 3.
Deposition of Kevin Ng (Benchmark Lead Engineer), January 7, 2025: Mr. Ng is the Lead Engineer at Benchmark Semiconductor Analysis, LLC who directed the teardown and reverse-engineering analyses of both accused products. During his deposition, Mr. Ng confirmed the teardown methodology employed, the chain of custody for all accused product samples, and the identification of specific structures on the accused products' PIC dies corresponding to each asserted claim limitation of the '847 Patent. Mr. Ng's testimony provides foundational support for the admissibility and reliability of the Benchmark teardown evidence cited throughout this claim chart. Specific page and line citations are set forth in Appendix 3.
D. Publicly Available Product Information
OWS has also relied on publicly available information published by Lumicore Technologies, Inc. regarding the accused products, including:
• Lumicore product data sheets for the LumiLink 400G-ZR+ and LumiLink 800G-DR8, which specify key performance parameters including insertion loss, channel count, operating wavelength range, and output power levels;
• Lumicore white papers describing the silicon photonic architecture employed in the LumiLink product family;
• Lumicore application notes providing technical guidance to customers on the deployment and integration of the LumiLink 400G-ZR+ and LumiLink 800G-DR8 in data-center interconnect environments; and
• Lumicore technical presentations delivered at industry conferences, including the Optical Fiber Communication Conference (OFC), the European Conference on Optical Communication (ECOC), and various IEEE Photonics Society events, in which Lumicore engineers described the waveguide multiplexer architecture and performance characteristics of the accused products.
These publicly available materials provide additional evidence of the structure and function of the accused products' waveguide multiplexer architectures, and corroborate the findings of the Benchmark teardown analyses and the Lumicore design documents produced in discovery.
E. Patent Prosecution History
OWS has reviewed and relies upon the complete prosecution history of the '847 Patent, as prosecuted before the United States Patent and Trademark Office by Cascade IP Advisors, LLC, with Dr. Martin Chu serving as Lead Prosecution Attorney. The prosecution history includes the original application, all office actions, amendments, arguments, and declarations submitted during prosecution, and the notice of allowance.
OWS has also reviewed the related prosecution history of the '562 Patent, which is in the same continuation family as the '847 Patent. The prosecution histories of both patents in this family are relevant to the construction of the asserted claims and to OWS's positions on claim scope as set forth in the Joint Claim Construction Statement and OWS's Opening Claim Construction Brief.
IV. CLAIM CONSTRUCTION POSITIONS
This claim chart reflects OWS's proposed claim constructions as set forth in the Joint Claim Construction Statement filed on October 28, 2024 (Dkt. No. 89), and OWS's Opening Claim Construction Brief filed on November 15, 2024 (Dkt. No. 102). There are fourteen (14) total disputed claim terms across all asserted patents in this action. The specific disputed terms relevant to the '847 Patent are addressed below. Terms not identified as disputed are given their plain and ordinary meaning as would be understood by a person of ordinary skill in the art ("POSITA") at the time of the invention.
A Markman hearing on claim construction is currently scheduled for March 14, 2025, before Judge Gilstrap. OWS expressly reserves the right to supplement or amend this claim chart, including the infringement mappings set forth herein, following the Court's Markman ruling and entry of a claim construction order.
A. "Waveguide Multiplexer" (Appears in Claims 1, 9)
The term "waveguide multiplexer" appears in both independent claims asserted in this claim chart (Claims 1 and 9). The parties have proposed competing constructions for this term, as follows:
OWS's Proposed Construction: "An optical device that combines multiple optical signals of different wavelengths onto a single waveguide."
OWS contends that this construction accurately reflects the plain and ordinary meaning of the term "waveguide multiplexer" as it would be understood by a POSITA in the field of silicon photonics and optical communications. The '847 Patent specification describes multiple embodiments of waveguide multiplexer structures, including arrayed waveguide gratings ("AWGs"), echelle gratings, cascaded Mach-Zehnder interferometer ("MZI") structures, and ring-resonator-based multiplexers. The claims do not limit the term "waveguide multiplexer" to any single one of these architectures, and the specification explicitly states that the invention "is not limited to any particular multiplexer topology" ('847 Patent, col. 4, ll. 32–34).
Lumicore's Proposed Construction: "An arrayed waveguide grating that combines optical signals using a slab coupler and phase-shifted waveguide array."
OWS contends that Lumicore's proposed construction improperly imports specific structural limitations from a single preferred embodiment described in the specification into the claim language. The Federal Circuit has repeatedly cautioned against reading limitations from preferred embodiments into claims. See, e.g., Phillips v. AWH Corp., 415 F.3d 1303, 1323 (Fed. Cir. 2005) (en banc) (holding that it is improper to confine claims to preferred embodiments). The claim language recites "waveguide multiplexer" without any limitation to a specific type of multiplexer architecture, and the specification's description of multiple multiplexer topologies confirms that the claim term is broader than Lumicore's proposed construction.
Impact on Infringement Analysis: As set forth in the detailed claim charts below, the accused products satisfy the "waveguide multiplexer" limitation under either party's proposed construction. The Benchmark teardown analyses identified waveguide multiplexer structures in both the LumiLink 400G-ZR+ and the LumiLink 800G-DR8 that satisfy OWS's broader proposed construction by combining multiple optical signals of different wavelengths onto a single waveguide. Moreover, even under Lumicore's narrower proposed construction, the accused products satisfy the limitation because the Benchmark analysis identified the presence of slab coupler regions and phase-shifted waveguide array elements in the multiplexer structures of both accused products.
B. Claim Differentiation Issue (Claims 1, 3, 5)
Calderwood & Harkness LLP's internal claim differentiation analysis, dated October 8, 2024, addresses Lumicore's argument that independent Claim 1 of the '847 Patent should be construed narrowly in light of dependent Claims 3 and 5. Lumicore has contended that certain features recited in dependent Claims 3 and 5 are inherent to the independent claim, and therefore that independent Claim 1 should be read to require those features.
OWS vigorously disputes this argument. The doctrine of claim differentiation creates a rebuttable presumption that each claim in a patent has a different scope. See Curtiss-Wright Flow Control Corp. v. Velan, Inc., 438 F.3d 1374, 1380 (Fed. Cir. 2006). Because dependent Claims 3 and 5 each add specific limitations that narrow the scope of independent Claim 1, the claim-differentiation doctrine requires that Claim 1 be construed more broadly than Claims 3 and 5. If Claim 1 were construed to already require the additional features recited in Claims 3 and 5, those dependent claims would be rendered superfluous—a result that is disfavored under Federal Circuit precedent.
This claim chart maps the limitations of Claim 1 under OWS's broader construction, consistent with the claim-differentiation doctrine. The additional limitations introduced by Claims 3 and 5 are mapped separately in Sections VI and VII below, confirming that the accused products satisfy not only the broader independent claim but also the narrower dependent claims.
C. Means-Plus-Function Limitation (Claim 9)
Calderwood & Harkness LLP's internal analysis, dated October 5, 2024, identified one limitation in independent Claim 9 of the '847 Patent as potentially constituting a means-plus-function limitation subject to 35 U.S.C. § 112(f). This limitation uses the phrase "means for" followed by a recitation of a specific function, without reciting sufficient structure to perform the claimed function.
Under 35 U.S.C. § 112(f), a means-plus-function claim limitation is construed to cover the corresponding structure disclosed in the specification for performing the recited function, and equivalents thereof. See Ostrander Holdings, 792 F.3d 1339, 1347–48 (Fed. Cir. 2015) (en banc).
Corresponding Structure Identified in Specification: OWS has identified the corresponding structure in the '847 Patent specification as the phase-compensating waveguide bridge structure described at column 7, lines 12–45, and illustrated in Figures 4A–4C of the '847 Patent. This structure comprises a set of auxiliary waveguide segments interconnecting the primary waveguide array arms with calibrated optical path length differentials, configured to compensate for phase errors introduced by fabrication variations in the waveguide array.
Function Performed: The function recited in the means-plus-function limitation is the compensation of phase errors across the waveguide array to reduce channel-dependent insertion loss variation.
As set forth in the detailed claim chart for Claim 9 (Section VIII below), the accused products include structures that are identical to, or equivalents of, the corresponding structure identified in the '847 Patent specification, and those structures perform the identical function in substantially the same way to achieve substantially the same result.
V. CLAIM CHART — CLAIM 1 (INDEPENDENT CLAIM)
Claim 1 of the '847 Patent is an independent claim directed to a multi-channel silicon photonic waveguide multiplexer apparatus. Each limitation of Claim 1 is set forth below, together with a detailed identification of the specific structures and features of each accused product that satisfy the limitation, and the specific evidence supporting each infringement contention.
Preamble
Claim Language: "A multi-channel silicon photonic waveguide multiplexer for combining a plurality of optical signals of different wavelengths onto a single output waveguide, the multiplexer comprising:"
LumiLink 400G-ZR+:
The LumiLink 400G-ZR+ is a silicon-photonics-based 400G coherent transceiver module that includes a multi-channel waveguide multiplexer integrated on a silicon photonic integrated circuit ("PIC"). The Benchmark teardown report dated December 12, 2022 identifies the waveguide multiplexer structure on the PIC die of the LumiLink 400G-ZR+ module. Specifically, the Benchmark report identifies a multiplexer structure occupying a region of approximately 1.8 mm × 0.9 mm on the PIC die, located between the modulator output waveguides and the edge coupler for fiber-to-chip coupling. (See Benchmark Teardown Report, LumiLink 400G-ZR+, Fig. 12 (die-level photograph with multiplexer region annotated); Fig. 14 (magnified optical micrograph of multiplexer region).)
Lumicore's publicly available product data sheets for the LumiLink 400G-ZR+ confirm that the module combines multiple optical wavelength channels onto a single output waveguide for DWDM transmission over single-mode fiber, consistent with the preamble's recitation of a "multi-channel silicon photonic waveguide multiplexer for combining a plurality of optical signals of different wavelengths onto a single output waveguide." (See Lumicore, LumiLink 400G-ZR+ Product Data Sheet, Rev. 3.2 (August 2023), at 2 ("The LumiLink 400G-ZR+ integrates a high-performance silicon photonic multiplexer for DWDM channel combining with best-in-class insertion loss performance.").)
To the extent the preamble is found to be limiting—which OWS does not concede—the LumiLink 400G-ZR+ satisfies the preamble of Claim 1.
LumiLink 800G-DR8:
The LumiLink 800G-DR8 is a silicon-photonics-based 800G transceiver module that includes a multi-channel waveguide multiplexer integrated on a silicon photonic integrated circuit. The Benchmark teardown report completed in June 2023 identifies the waveguide multiplexer structure on the PIC die of the LumiLink 800G-DR8 module. The 800G-DR8 module combines eight wavelength channels using a waveguide multiplexer for parallel single-mode fiber ("PSM") transmission, with each wavelength channel carrying a 100G signal for a total aggregate bandwidth of 800G. (See Benchmark Teardown Report, LumiLink 800G-DR8, Fig. 8 (die-level photograph with multiplexer region annotated); Fig. 11 (magnified optical micrograph of eight-channel multiplexer region).)
Lumicore's publicly available product data sheets for the LumiLink 800G-DR8 confirm the presence of a multi-channel waveguide multiplexer on the silicon PIC, combining multiple wavelength channels onto a single output waveguide. (See Lumicore, LumiLink 800G-DR8 Product Data Sheet, Rev. 2.1 (March 2024), at 3.)
To the extent the preamble is found to be limiting, the LumiLink 800G-DR8 satisfies the preamble of Claim 1.
Limitation 1(a)
Claim Language: "a silicon substrate having a plurality of input waveguides formed thereon, each input waveguide configured to receive an optical signal at a respective wavelength;"
LumiLink 400G-ZR+:
The Benchmark teardown photographs and SEM cross-sections of the LumiLink 400G-ZR+ PIC die confirm that the device is fabricated on a silicon substrate, specifically a silicon-on-insulator ("SOI") platform. The SOI substrate comprises a silicon handle wafer, a buried oxide ("box") layer, and a thin silicon device layer in which the waveguide structures are formed by lithographic patterning and etching. (See Benchmark Teardown Report, LumiLink 400G-ZR+, Fig. 18 (SEM cross-section of waveguide layer stack showing SOI structure); Fig. 19 (magnified SEM cross-section of individual waveguide with silicon core and SiO₂ cladding).)
The Benchmark teardown analysis further identifies multiple input waveguides formed on the silicon substrate, each routing an optical signal from a corresponding laser source or modulator output to the input of the waveguide multiplexer structure. Each input waveguide carries a distinct wavelength channel within the ITU-T C-band grid, as confirmed by the Lumicore product data sheet and internal engineering specifications. (See Benchmark Teardown Report, LumiLink 400G-ZR+, Fig. 20 (annotated die photograph showing input waveguides routed from modulator outputs to multiplexer input ports).)
Lumicore design documents produced in discovery, bearing Bates numbers LC-OPTI-00045821 through LC-OPTI-00045867, designated "Highly Confidential — Attorneys' Eyes Only," confirm the use of a plurality of input waveguides on a silicon substrate, with each input waveguide accepting an optical signal from a corresponding laser source at a specific wavelength within the C-band. These design documents specify the number of input waveguide channels, the waveguide dimensions (width and height), and the wavelength assignments for each input channel.
The LumiLink 400G-ZR+ satisfies Limitation 1(a) of Claim 1.
LumiLink 800G-DR8:
The Benchmark teardown report for the LumiLink 800G-DR8 (June 2023) confirms that the 800G-DR8 PIC is fabricated on an SOI substrate with multiple input waveguides formed in the silicon device layer. The Benchmark SEM cross-sections show the same SOI layer stack as observed in the LumiLink 400G-ZR+, consistent with fabrication on a common silicon photonic platform. (See Benchmark Teardown Report, LumiLink 800G-DR8, Fig. 15 (SEM cross-section of SOI waveguide structure).)
The Benchmark teardown identifies eight input waveguides, each receiving an optical signal at a different wavelength from a corresponding directly modulated laser ("DML") or electro-absorption modulated laser ("EML") source. (See Benchmark Teardown Report, LumiLink 800G-DR8, Fig. 16 (annotated die photograph showing eight input waveguides routed to multiplexer input ports).)
Lumicore engineering specifications produced in discovery, bearing Bates numbers LC-OPTI-00078432 through LC-OPTI-00078498, confirm the architecture of the 800G-DR8 with eight separate input waveguide channels on the silicon substrate, each configured to receive an optical signal at a respective wavelength channel.
The LumiLink 800G-DR8 satisfies Limitation 1(a) of Claim 1.
Limitation 1(b)
Claim Language: "a waveguide multiplexer structure optically coupled to the plurality of input waveguides, the waveguide multiplexer structure configured to combine the plurality of optical signals onto a single output waveguide;"
LumiLink 400G-ZR+:
The Benchmark die-level photographs of the LumiLink 400G-ZR+ PIC show a waveguide multiplexer structure that is optically coupled to the plurality of input waveguides identified in connection with Limitation 1(a) above. The waveguide multiplexer structure has been identified by Benchmark as an arrayed waveguide grating ("AWG") or echelle grating variant, comprising slab coupler regions at the input and output sides of the multiplexer, and a phased array of waveguide arms connecting the two slab coupler regions. The multiplexer combines the multiple wavelength channels received at the input waveguides onto a single output waveguide that routes the combined signal to the edge coupler for fiber coupling. (See Benchmark Teardown Report, LumiLink 400G-ZR+, Fig. 22 (annotated optical micrograph of multiplexer structure showing input slab coupler, waveguide array, and output slab coupler); Fig. 23 (magnified view of waveguide array arms); Fig. 24 (magnified view of output slab coupler and single output waveguide).)
Deposition testimony of Kevin Ng (January 7, 2025) confirmed the identification of this waveguide multiplexer structure and its function of combining multiple wavelength channels onto a single output waveguide. Mr. Ng testified:
"Q: Can you identify the structure that you labeled as the waveguide multiplexer in Figure 22 of your teardown report?
A: Yes. This is the waveguide multiplexer structure. It consists of an input slab coupler region here [indicating], a phased array of waveguide arms connecting the input slab to the output slab coupler here [indicating], and a single output waveguide emerging from the output slab coupler here [indicating]. The function of this structure is to combine the multiple input wavelength channels into a single combined output on the output waveguide."
(Ng Dep., Jan. 7, 2025, at 87:14–88:3.)
Under OWS's proposed construction of "waveguide multiplexer"—i.e., "an optical device that combines multiple optical signals of different wavelengths onto a single waveguide"—the identified structure in the LumiLink 400G-ZR+ clearly satisfies this limitation, as it is an optical device that combines multiple optical signals of different wavelengths onto a single waveguide.
Even under Lumicore's narrower proposed construction of "waveguide multiplexer"—i.e., "an arrayed waveguide grating that combines optical signals using a slab coupler and phase-shifted waveguide array"—the structure in the LumiLink 400G-ZR+ meets the limitation. The Benchmark analysis specifically identified the presence of slab coupler regions at both the input and output sides of the multiplexer, and a phase-shifted waveguide array connecting the slab coupler regions. (See Benchmark Teardown Report, LumiLink 400G-ZR+, Fig. 25 (SEM image of slab coupler region); Fig. 26 (SEM image of phase-shifted waveguide array arms with measured path length differentials).)
The LumiLink 400G-ZR+ satisfies Limitation 1(b) of Claim 1 under either proposed construction of "waveguide multiplexer."
LumiLink 800G-DR8:
The Benchmark teardown report for the LumiLink 800G-DR8 (June 2023) identifies a substantially similar waveguide multiplexer structure on the 800G-DR8 PIC die. The structure combines eight wavelength channels onto a single output waveguide and exhibits the same architectural elements as the multiplexer in the LumiLink 400G-ZR+, including slab coupler regions and a phased waveguide array. (See Benchmark Teardown Report, LumiLink 800G-DR8, Fig. 18 (annotated optical micrograph of eight-channel multiplexer structure); Fig. 19 (magnified view of waveguide array arms); Fig. 20 (magnified view of output slab coupler and single output waveguide).)
Lumicore design files produced in discovery, bearing Bates numbers LC-OPTI-00079102 through LC-OPTI-00079156, confirm the multiplexer architecture of the 800G-DR8, including the use of a waveguide multiplexer structure optically coupled to the eight input waveguides and configured to combine all eight wavelength channels onto a single output waveguide.
The LumiLink 800G-DR8 satisfies Limitation 1(b) of Claim 1 under either proposed construction of "waveguide multiplexer."
Limitation 1(c)
Claim Language: "wherein the waveguide multiplexer structure exhibits an insertion loss of less than 1.5 dB per channel across all channels of the plurality of optical signals;"
LumiLink 400G-ZR+:
Lumicore's publicly available product data sheets for the LumiLink 400G-ZR+ specify the insertion loss of the integrated waveguide multiplexer at 1.2 dB per channel (typical) and 1.4 dB per channel (maximum) across all DWDM channels within the operating wavelength range. Both the typical and maximum specified insertion loss values are below the 1.5 dB per channel threshold recited in Claim 1 of the '847 Patent. (See Lumicore, LumiLink 400G-ZR+ Product Data Sheet, Rev. 3.2 (August 2023), at 5, Table 2 ("Optical Multiplexer Performance Specifications").)
Benchmark testing of the teardown sample measured insertion loss values consistent with, and in some channels slightly better than, the values specified in the Lumicore product data sheet. Specifically, Benchmark measured insertion loss values ranging from 0.95 dB to 1.35 dB across all channels of the multiplexer in the teardown sample. (See Benchmark Teardown Report, LumiLink 400G-ZR+, Table 5 ("Measured Insertion Loss by Channel").)
Internal Lumicore engineering test data produced in discovery, bearing Bates numbers LC-OPTI-00052104 through LC-OPTI-00052118, designated "Highly Confidential — Attorneys' Eyes Only," confirms measured insertion loss values across production lots of the LumiLink 400G-ZR+ multiplexer consistently falling below 1.5 dB per channel, with lot-average values typically in the range of 1.0 dB to 1.3 dB per channel.
The LumiLink 400G-ZR+ satisfies Limitation 1(c) of Claim 1.
LumiLink 800G-DR8:
Lumicore's product specifications for the LumiLink 800G-DR8 specify the insertion loss of the integrated waveguide multiplexer at 1.1 dB per channel (typical) and 1.3 dB per channel (maximum) across all eight wavelength channels. Both the typical and maximum specified insertion loss values are below the 1.5 dB per channel threshold recited in Claim 1. (See Lumicore, LumiLink 800G-DR8 Product Data Sheet, Rev. 2.1 (March 2024), at 6, Table 3 ("Optical Multiplexer Performance Specifications").)
Benchmark testing of the 800G-DR8 teardown sample measured insertion loss values ranging from 0.88 dB to 1.22 dB across all eight channels. (See Benchmark Teardown Report, LumiLink 800G-DR8, Table 4 ("Measured Insertion Loss by Channel").) Internal Lumicore engineering test data, bearing Bates numbers LC-OPTI-00082445 through LC-OPTI-00082461, confirms measured insertion loss values consistently below 1.5 dB per channel across production lots.
The LumiLink 800G-DR8 satisfies Limitation 1(c) of Claim 1.
Limitation 1(d)
Claim Language: "wherein the waveguide multiplexer structure comprises tapered waveguide transitions at interfaces between the plurality of input waveguides and the waveguide multiplexer structure, and between the waveguide multiplexer structure and the single output waveguide, the tapered waveguide transitions configured to minimize mode-mismatch loss at said interfaces."
LumiLink 400G-ZR+:
SEM cross-sectional images from the Benchmark teardown of the LumiLink 400G-ZR+ PIC clearly show tapered waveguide transitions at the interfaces between the input waveguides and the input slab coupler of the multiplexer, and at the interface between the output slab coupler and the single output waveguide. These tapered transitions are visible as gradual expansions of the waveguide width from the narrow single-mode waveguide dimensions (approximately 450–500 nm width) to the wider slab coupler aperture dimensions (approximately 1.5–2.5 μm width), with the taper extending over a length of approximately 50–100 μm. (See Benchmark Teardown Report, LumiLink 400G-ZR+, Fig. 28 (SEM image of tapered transition at input waveguide-to-slab coupler interface); Fig. 29 (SEM image of tapered transition at output slab coupler-to-output waveguide interface); Fig. 30 (measured taper profile showing width as a function of propagation distance).)
Lumicore design layout files produced in discovery, bearing Bates numbers LC-OPTI-00046230 through LC-OPTI-00046278, designated "Highly Confidential — Source Code," show the coupler geometry and waveguide dimension parameters for the tapered transitions. These design files specify the taper shape (linear or adiabatic), the taper length, and the input and output widths of the tapered transitions, consistent with the structural features observed in the Benchmark teardown.
Deposition testimony of Dr. Sandra Michaud (November 19, 2024) further confirms the design rationale for the tapered transitions:
"Q: Can you describe the approach your team used in designing the multiplexer for the LumiLink product line to minimize insertion loss?
A: One of the key design techniques we employed was the use of tapered waveguide transitions at the input and output interfaces of the multiplexer. The tapers are designed to gradually expand the waveguide mode field from the narrow single-mode waveguide to the wider slab coupler aperture, which minimizes mode-mismatch loss at those interfaces. This is a well-known technique in integrated photonics, but we optimized the taper geometry to achieve very low loss."
(Michaud Dep., Nov. 19, 2024, at 142:8–143:1.)
Dr. Michaud's testimony directly confirms that the LumiLink multiplexer incorporates tapered waveguide transitions configured to minimize mode-mismatch loss, precisely as recited in Limitation 1(d) of Claim 1.
The LumiLink 400G-ZR+ satisfies Limitation 1(d) of Claim 1.
LumiLink 800G-DR8:
Benchmark SEM images and cross-sectional analyses of the LumiLink 800G-DR8 PIC show equivalent tapered waveguide transition structures at the input and output interfaces of the eight-channel multiplexer. The taper geometry and dimensions observed in the 800G-DR8 are substantially similar to those observed in the LumiLink 400G-ZR+, consistent with the use of a common silicon photonic platform and design methodology. (See Benchmark Teardown Report, LumiLink 800G-DR8, Fig. 24 (SEM image of tapered transition at input waveguide-to-slab coupler interface); Fig. 25 (SEM image of tapered transition at output slab coupler-to-output waveguide interface).)
Lumicore design files for the 800G-DR8, bearing Bates numbers LC-OPTI-00079425 through LC-OPTI-00079468, confirm the presence and dimensions of tapered waveguide transitions at the multiplexer input and output interfaces, consistent with the claimed structural feature of tapered transitions configured to minimize mode-mismatch loss.
The LumiLink 800G-DR8 satisfies Limitation 1(d) of Claim 1.
VI. CLAIM CHART — CLAIM 3 (DEPENDENT ON CLAIM 1)
Dependency
Claim 3 depends from Claim 1 and therefore includes all limitations of Claim 1. As set forth in Section V above, both the LumiLink 400G-ZR+ and the LumiLink 800G-DR8 satisfy every limitation of Claim 1 on a literal infringement basis. The analysis of Claim 1 limitations is incorporated herein by reference and is not repeated.
Additional Limitation of Claim 3
Claim Language: "The multi-channel silicon photonic waveguide multiplexer of claim 1, wherein the waveguide multiplexer structure comprises an arrayed waveguide grating having at least four channels, and wherein the arrayed waveguide grating comprises a first slab coupler region, a second slab coupler region, and a plurality of waveguide array arms connecting the first slab coupler region and the second slab coupler region, each waveguide array arm having a different optical path length."
LumiLink 400G-ZR+:
The Benchmark teardown data for the LumiLink 400G-ZR+ identifies the waveguide multiplexer structure as an arrayed waveguide grating ("AWG") having at least four channels. Specifically, the Benchmark analysis identified a multiplexer with multiple DWDM channels (the exact channel count is confirmed in Lumicore design documents bearing Bates numbers LC-OPTI-00045821 through LC-OPTI-00045867, designated "Highly Confidential — Attorneys' Eyes Only," which specify the number of channels as exceeding four).
The Benchmark teardown photographs further identify the structural components of the AWG, including:
(i) A first slab coupler region at the input side of the AWG, where the plurality of input waveguides fan out into the slab waveguide region (see Benchmark Teardown Report, LumiLink 400G-ZR+, Fig. 25 (SEM image of input slab coupler region));
(ii) A second slab coupler region at the output side of the AWG, where the waveguide array arms converge and the combined signal is focused onto the single output waveguide (see Benchmark Teardown Report, LumiLink 400G-ZR+, Fig. 26 (SEM image of output slab coupler region));
(iii) A plurality of waveguide array arms connecting the first slab coupler region and the second slab coupler region, each arm having a different optical path length to produce the wavelength-dependent phase shifts necessary for multiplexing operation (see Benchmark Teardown Report, LumiLink 400G-ZR+, Fig. 23 (optical micrograph of waveguide array arms with measured path length differentials annotated)).
The measured path length differentials between adjacent waveguide array arms, as reported in the Benchmark teardown report, confirm that each waveguide array arm has a different optical path length, consistent with the design requirements of an AWG for wavelength multiplexing.
Lumicore design documents bearing Bates numbers LC-OPTI-00046012 through LC-OPTI-00046089 describe the AWG architecture in detail, including the number of waveguide array arms, the incremental path length difference (ΔL) between adjacent arms, the free spectral range (FSR), and the channel spacing. These documents confirm that the LumiLink 400G-ZR+ multiplexer is an arrayed waveguide grating with at least four channels, comprising first and second slab coupler regions and a plurality of waveguide array arms with different optical path lengths, as recited in Claim 3.
The LumiLink 400G-ZR+ satisfies the additional limitation of Claim 3.
LumiLink 800G-DR8:
The Benchmark teardown report for the LumiLink 800G-DR8 (June 2023) identifies a substantially similar AWG structure on the 800G-DR8 PIC, with eight channels (exceeding the "at least four channels" requirement of Claim 3). The Benchmark analysis identified the first slab coupler region, the second slab coupler region, and the plurality of waveguide array arms connecting the two slab coupler regions, with each arm having a different optical path length. (See Benchmark Teardown Report, LumiLink 800G-DR8, Figs. 18–22.)
Lumicore design files bearing Bates numbers LC-OPTI-00079102 through LC-OPTI-00079256 confirm the eight-channel AWG architecture of the 800G-DR8 multiplexer, including the incremental path length difference between adjacent waveguide array arms.
The LumiLink 800G-DR8 satisfies the additional limitation of Claim 3.
Claim Differentiation Note: The fact that Claim 3 narrows the scope of Claim 1 by requiring the specific AWG architecture with at least four channels, first and second slab coupler regions, and waveguide array arms with different optical path lengths, confirms—under the doctrine of claim differentiation—that independent Claim 1 is broader and does not require these specific structural features. This analysis is consistent with OWS's claim differentiation memorandum dated October 8, 2024.
VII. CLAIM CHART — CLAIM 5 (DEPENDENT ON CLAIM 1)
Dependency
Claim 5 depends from Claim 1 and therefore includes all limitations of Claim 1. As set forth in Section V above, both the LumiLink 400G-ZR+ and the LumiLink 800G-DR8 satisfy every limitation of Claim 1 on a literal infringement basis. The analysis of Claim 1 limitations is incorporated herein by reference and is not repeated.
Additional Limitation of Claim 5
Claim Language: "The multi-channel silicon photonic waveguide multiplexer of claim 1, further comprising a thermal compensation structure integrated with the waveguide multiplexer structure, the thermal compensation structure configured to maintain the insertion loss of less than 1.5 dB per channel over an operating temperature range of at least 0°C to 70°C."
LumiLink 400G-ZR+:
The Benchmark teardown analysis of the LumiLink 400G-ZR+ identified a thermal compensation structure integrated with the waveguide multiplexer on the PIC die. Specifically, the Benchmark teardown report identifies resistive heater elements positioned over the waveguide array arms of the multiplexer, connected to control circuitry on the PIC that adjusts the heater power in response to temperature variations to maintain the multiplexer's center wavelength alignment and insertion loss performance. (See Benchmark Teardown Report, LumiLink 400G-ZR+, Fig. 32 (optical micrograph showing resistive heater elements over waveguide array arms); Fig. 33 (SEM cross-section of heater element layer above waveguide core layer).)
Lumicore engineering test data produced in discovery, bearing Bates numbers LC-OPTI-00053201 through LC-OPTI-00053248, designated "Highly Confidential — Attorneys' Eyes Only," includes temperature-dependent insertion loss measurements for the LumiLink 400G-ZR+ multiplexer. These measurements demonstrate that, with the thermal compensation structure active, the multiplexer maintains insertion loss of less than 1.5 dB per channel across all channels over the operating temperature range of -5°C to 75°C—which encompasses and exceeds the "at least 0°C to 70°C" range recited in Claim 5. The data shows that without thermal compensation (heaters off), the insertion loss degrades significantly at the edges of the temperature range, exceeding 2.0 dB per channel at certain wavelengths at elevated temperatures. With thermal compensation active, insertion loss remains below 1.4 dB per channel across all temperatures and all channels.
Lumicore's publicly available product data sheet for the LumiLink 400G-ZR+ specifies the operating case temperature range as -5°C to 75°C and guarantees the multiplexer insertion loss specification of 1.4 dB per channel (maximum) across this temperature range. (See Lumicore, LumiLink 400G-ZR+ Product Data Sheet, Rev. 3.2 (August 2023), at 4, Table 1 ("Operating Conditions") and at 5, Table 2 ("Optical Multiplexer Performance Specifications" (note 3: "Insertion loss specification guaranteed over full operating temperature range with thermal compensation active")).)
The LumiLink 400G-ZR+ satisfies the additional limitation of Claim 5.
LumiLink 800G-DR8:
The Benchmark teardown report for the LumiLink 800G-DR8 (June 2023) identifies an equivalent thermal compensation structure on the 800G-DR8 PIC, comprising resistive heater elements integrated with the eight-channel waveguide multiplexer. (See Benchmark Teardown Report, LumiLink 800G-DR8, Figs. 28–29 (optical micrograph and SEM cross-section of heater elements).)
Lumicore engineering test data produced in discovery, bearing Bates numbers LC-OPTI-00083901 through LC-OPTI-00083945, confirms that the 800G-DR8 multiplexer maintains insertion loss of less than 1.5 dB per channel across all eight channels over the operating temperature range of 0°C to 70°C (and beyond, up to 75°C), with the thermal compensation structure active. Lumicore's product data sheet for the 800G-DR8 similarly specifies the multiplexer insertion loss over the full operating temperature range with thermal compensation. (See Lumicore, LumiLink 800G-DR8 Product Data Sheet, Rev. 2.1 (March 2024), at 6, Table 3.)
The LumiLink 800G-DR8 satisfies the additional limitation of Claim 5.
Claim Differentiation Note: The additional limitation of Claim 5—requiring a thermal compensation structure to maintain insertion loss performance over an operating temperature range—confirms that independent Claim 1 does not require a thermal compensation structure. This is consistent with OWS's claim differentiation analysis dated October 8, 2024, and supports the broader scope of Claim 1 as proposed by OWS.
VIII. CLAIM CHART — CLAIM 9 (INDEPENDENT CLAIM)
Claim 9 of the '847 Patent is an independent claim. Each limitation of Claim 9 is set forth below, together with a detailed identification of the specific structures and features of each accused product that satisfy the limitation, and the specific evidence supporting each infringement contention. Limitation 9(c) has been identified as potentially invoking 35 U.S.C. § 112(f) and is analyzed accordingly.
Preamble
Claim Language: "A silicon photonic multiplexer apparatus for wavelength-division multiplexing of optical signals in a photonic integrated circuit, the apparatus comprising:"