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MEMORANDUM

PRIVILEGED AND CONFIDENTIAL — ATTORNEY WORK PRODUCT

THIS MEMORANDUM IS PROTECTED BY THE ATTORNEY-CLIENT PRIVILEGE AND THE WORK PRODUCT DOCTRINE. IT HAS BEEN PREPARED IN ANTICIPATION OF LITIGATION AND REFLECTS THE MENTAL IMPRESSIONS, CONCLUSIONS, AND LEGAL THEORIES OF COUNSEL. THIS MEMORANDUM IS NOT TO BE DISCLOSED TO ANY THIRD PARTY WITHOUT THE EXPRESS WRITTEN CONSENT OF CALDERWOOD & HARKNESS LLP.

TO: Dr. Caroline Ashford, Professor of Electrical Engineering & Photonics, Northfield Institute of Technology, Evanston, IL

FROM: Alan Ngo, Responsible Partner; Wendy Schultz, Lead Associate; Omar Siddiqui, Working Associate — Calderwood & Harkness LLP

DATE: July 21, 2025

RE: Deposition Preparation — Optiwave Semiconductor Corp. v. Lumicore Technologies, Inc., Case No. 2:24-cv-00319-JRG (E.D. Tex.)

SUBJECT: Preparation for Expert Deposition of Dr. Caroline Ashford by Hawthorne Vega & Cruz LLP

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I. PURPOSE AND SCOPE OF THIS MEMORANDUM

This memorandum has been prepared by Calderwood & Harkness LLP ("C&H") to assist Dr. Caroline Ashford in preparing for her upcoming deposition in the above-referenced matter. The deposition is anticipated to be taken by Hawthorne Vega & Cruz LLP ("HVC"), counsel for Defendant Lumicore Technologies, Inc. ("Lumicore"). Based on our assessment of opposing counsel's litigation team, we anticipate that the deposition will be conducted by lead partner Catherine "Kate" Rourke and/or second chair partner Darren Cho, both of whom have substantial experience in complex patent litigation and are skilled cross-examiners.

The deposition is expected to be scheduled in late July or early August 2025. This timing follows the service of Dr. Ashford's two expert reports on June 15, 2025, and falls before the expert discovery close date of August 15, 2025, as set by the Court's Scheduling Order (Docket Entry ("D.E.") 22, entered August 12, 2024). Accordingly, we must use the intervening weeks to prepare thoroughly for what we anticipate will be an extensive and technically rigorous cross-examination.

As a preliminary matter, Dr. Ashford has submitted two expert reports on behalf of Plaintiff Optiwave Semiconductor Corp. ("OWS"):

(1) Expert Report on Infringement — In this report, Dr. Ashford opines that each of the accused Lumicore products — specifically, the LumiLink 400G-ZR+, the LumiLink 800G-DR8, and the LumiEdge 1600G-LR — infringes each asserted claim of U.S. Patent Nos. 10,234,847 (the "'847 Patent"), 10,891,193 (the "'193 Patent"), 9,678,562 (the "'562 Patent"), and 11,402,015 (the "'015 Patent"), both literally and under the doctrine of equivalents where applicable.

(2) Expert Report on Validity — In this report, Dr. Ashford rebuts Lumicore's invalidity contentions, which were served on October 14, 2024, and which address all 23 prior-art references cited by Lumicore across the four asserted patents. Dr. Ashford opines that none of the cited prior-art references, individually or in combination, anticipates or renders obvious any asserted claim of any of the four patents-in-suit.

This memorandum is organized to address the following topics in sequence, each of which is discussed at length in the sections that follow:

(a) General deposition guidance, including format, logistics, and principles of demeanor;

(b) Anticipated lines of cross-examination, organized by topic and by patent, including qualifications and bias, person of ordinary skill in the art ("POSITA") definition, literal infringement, doctrine of equivalents, prosecution history estoppel, validity opinions, and reliance on Benchmark Semiconductor Analysis, LLC data;

(d) Recommended responses and pitfalls to avoid on each major topic;

(e) Areas requiring particular care, including the doctrine of equivalents analysis for the '193 and '015 Patents, prosecution history estoppel under Festo Corp. v. Fenmore & Co., 535 U.S. 722 (2002), the POSITA definition and its implications for both infringement and validity, and the extent and nature of Dr. Ashford's reliance on the Benchmark Semiconductor Analysis, LLC teardown data.

We emphasize that this memorandum reflects counsel's litigation strategy, mental impressions, and assessment of the strengths and weaknesses of particular arguments. Its contents should not be disclosed to any third party, and Dr. Ashford should not reference this memorandum or its contents during the deposition itself. If asked about communications with counsel, Dr. Ashford should defer to the assertion of privilege by C&H attorneys present at the deposition.

II. GENERAL DEPOSITION GUIDANCE

A. Deposition Format and Logistics

Dr. Ashford's deposition will be taken pursuant to Federal Rule of Civil Procedure 30 and the applicable local rules of the Eastern District of Texas. We anticipate that HVC will notice the deposition for the presumptive limit of seven hours of examination in a single day, although it is possible that HVC may seek leave of Court to extend the duration given that Dr. Ashford submitted two separate expert reports addressing both infringement and validity. In the event that HVC moves for additional time, we will evaluate whether to oppose that motion or to stipulate to a reasonable extension. Dr. Ashford should plan for the possibility of a full day of examination and should not schedule other commitments for the day immediately following the deposition in case of any overflow.

The location of the deposition has not yet been confirmed. Based on prior practice in this case, we expect HVC will designate either its Austin, Texas office at 600 Congress Avenue, Suite 2400, Austin, TX 78701, or will agree to conduct the deposition by videoconference. If the deposition is conducted in person in Austin, C&H will arrange travel and accommodations for Dr. Ashford. If it is conducted by videoconference, Dr. Ashford should plan to be located in a quiet, professional setting with reliable internet connectivity, a neutral background, and appropriate lighting. We will confirm the format and location once the deposition notice is received and will coordinate logistics at that time.

A court reporter will be present (or connected remotely) to create a stenographic transcript. We also expect HVC to retain a videographer to create a video recording of the deposition. Under Rule 30(b)(3)(A), HVC is entitled to record the deposition by video as well as by stenographic means, and we should assume that any video recording may be used at trial for impeachment purposes or as substantive evidence if Dr. Ashford is unavailable at trial (although we fully expect Dr. Ashford to testify live). The video recording means that Dr. Ashford's demeanor, body language, and tone will be preserved, which makes the guidance in Section II.C below all the more important.

C&H attorneys will attend the deposition. We anticipate that either Alan Ngo (Responsible Partner) or Wendy Schultz (Lead Associate) — or both — will be present and will assert objections on the record where appropriate. However, Dr. Ashford should understand the following important principle: she should not look to counsel for signals or guidance during questioning. Under the Federal Rules and the ethical rules governing depositions, counsel may assert objections (e.g., objections to form, privilege, and the like) but generally may not coach the witness. Dr. Ashford should pause briefly — approximately two to three seconds — after each question before beginning her answer. This pause serves two purposes: (1) it gives counsel the opportunity to assert any objection before Dr. Ashford answers; and (2) it gives Dr. Ashford time to consider the question carefully before responding. If an objection is asserted, Dr. Ashford should wait for counsel to complete the objection and then, unless instructed not to answer (which will occur only in rare circumstances, such as questions that implicate the attorney-client privilege), should proceed to answer the question as asked.

B. Core Deposition Principles

The following principles are foundational to effective deposition testimony. While Dr. Ashford is an experienced academic and has previously testified as an expert witness, we review these principles here because they bear repeating in the context of this particular case, where the technical complexity of the subject matter and the sophistication of opposing counsel create unique challenges.

Listen to the full question before answering; answer only the question asked. This is the single most important principle of deposition practice. Opposing counsel will craft their questions carefully, and Dr. Ashford should not begin formulating her answer until the question has been fully stated. Many witnesses — particularly expert witnesses who are deeply familiar with the subject matter — have a tendency to anticipate where a question is heading and to begin answering before the questioner has finished. This tendency should be resisted. A complete, carefully phrased question may differ materially from the question Dr. Ashford anticipated, and a premature answer may volunteer information that was not called for.

Do not volunteer information beyond the scope of the question. Dr. Ashford's natural inclination as an educator and researcher may be to provide thorough, comprehensive explanations. In a deposition, however, less is more. If a question can be answered with "yes" or "no," a one-word answer is generally appropriate, though Dr. Ashford may add a brief qualifier if a bare "yes" or "no" would be misleading. The key principle is that Dr. Ashford should answer the question that was asked — not the question she wishes had been asked, and not a broader question that would allow her to deliver a more complete explanation. There will be opportunities at trial to provide full explanations; the deposition is opposing counsel's examination, and its purpose is to gather information and lock in testimony, not to provide Dr. Ashford a platform for advocacy.

If a question is unclear, ask for clarification; do not guess at meaning. Opposing counsel may ask questions that are ambiguous, compound, or that use technical terms imprecisely. Dr. Ashford should not attempt to interpret an unclear question and answer based on her best guess of what was meant. Instead, she should ask the questioner to rephrase or clarify the question. Responses such as "Could you clarify what you mean by [term]?" or "I'm not sure I understand the question — could you rephrase it?" are entirely appropriate. This practice protects Dr. Ashford from having her answers taken out of context based on an interpretation of the question that differs from what she understood.

It is always acceptable to say "I don't know" or "I don't recall" if that is truthful. Dr. Ashford is under oath and is obligated to testify truthfully. If she does not know the answer to a question, she should say so. If she does not recall a particular fact, date, or conversation, she should say so. She should not speculate or guess in order to avoid these answers. There is no requirement that an expert witness have the answer to every question, and an honest "I don't know" is far more effective — and far less dangerous — than a speculative answer that may later prove incorrect.

Do not speculate; opinions should be grounded in the analysis set forth in the expert reports. Dr. Ashford's expert opinions are the opinions set forth in her two reports served on June 15, 2025. Opposing counsel may attempt to elicit opinions on topics that go beyond the scope of those reports — for example, by asking hypothetical questions or by asking Dr. Ashford to opine on issues she did not address. Unless the question calls for an opinion that is fairly within the scope of her reports, Dr. Ashford should decline to offer an opinion on the spot. Appropriate responses include: "I did not address that question in my report," "That is outside the scope of my analysis," or "I would need to review additional materials before offering an opinion on that topic."

Be aware that opposing counsel may attempt to establish friendly rapport, then shift to adversarial questioning. This is a common and effective deposition technique. The questioner begins with easy, non-threatening questions — biographical background, general descriptions of the technology, areas where the experts may agree — to put the witness at ease and establish a pattern of agreeable answers. Then, once the witness has relaxed into a pattern of conceding points, the questioner transitions to substantive and contested issues, hoping to carry forward the witness's cooperativeness into areas where concessions are harmful. Dr. Ashford should maintain a consistent demeanor throughout the deposition — polite, professional, and measured — regardless of whether the questioning feels friendly or adversarial.

Avoid absolute statements ("always," "never") unless the technical basis is unambiguous. Absolute statements are easy to attack on cross-examination and can be used to undermine credibility if even a single exception can be identified. It is generally preferable to use qualifying language such as "in my experience," "based on my review of the relevant literature," "to my knowledge," or "in the context of this analysis." The exception is where a technical principle is genuinely absolute — for example, a fundamental law of physics — in which case an unqualified statement is appropriate.

If shown a document, read it carefully before answering questions about it. Opposing counsel will likely present Dr. Ashford with numerous documents during the deposition — patent claims, prosecution history excerpts, prior-art references, teardown report pages, deposition transcript excerpts, and the like. When a document is placed before her, Dr. Ashford should take the time to read the relevant portions carefully before answering any questions about it. She should not rely on opposing counsel's characterization of what a document says; she should read it herself. If the document is lengthy, she may ask to be directed to the specific portion the questioner is asking about, and she should still read that portion in full before answering.

Do not characterize communications with C&H counsel or the substance of privileged discussions. Opposing counsel may ask questions designed to probe the nature, substance, or extent of Dr. Ashford's communications with C&H. These communications are protected by the attorney-client privilege and the work product doctrine. Dr. Ashford should not describe what counsel told her, what instructions she received, what legal conclusions were shared with her, or the substance of any conversations with C&H attorneys about litigation strategy. If such a question is asked, C&H counsel will assert the privilege on the record, and Dr. Ashford should refrain from answering. The one area where some disclosure is required relates to the facts and data Dr. Ashford considered in forming her opinions, which are discoverable under Federal Rule of Civil Procedure 26(b)(4)(C)(ii). However, even in this area, the distinction between "facts or data considered" and "privileged communications with counsel" should be carefully maintained, and C&H counsel will guide any necessary assertions of privilege during the deposition.

C. Demeanor

Dr. Ashford should project calm authority throughout the deposition. Her credentials — Professor of Electrical Engineering & Photonics at the Northfield Institute of Technology, with a distinguished record of research and publication in silicon photonics — speak for themselves. She does not need to be assertive or defensive in order to be credible; indeed, the most effective expert witnesses are those who are direct, confident, and fair-minded.

Dr. Ashford should avoid appearing combative or evasive. An expert who quarrels with opposing counsel or who evades straightforward questions damages her own credibility. Judges and juries reviewing deposition transcripts — or watching deposition video clips at trial — are perceptive about witness credibility, and they respond favorably to witnesses who answer questions honestly and without evasion, even when the questions are difficult.

An important corollary of this principle: if a question calls for a concession that is technically accurate, Dr. Ashford should make it cleanly and without equivocation. Credibility is the expert's most valuable asset, and an expert who refuses to acknowledge obvious truths — or who quibbles over immaterial points — undermines her credibility on the points that actually matter. For example, if opposing counsel asks whether a particular prior-art reference discloses certain elements of a claimed invention, and it plainly does, Dr. Ashford should acknowledge the disclosure and then, if appropriate, explain why other elements are missing or why the reference is distinguishable on other grounds. The concession on the easy point actually enhances Dr. Ashford's credibility when she contests the harder points.

Finally, Dr. Ashford should be aware of her physical presentation. She should maintain good posture, make appropriate eye contact with the questioner (or with the camera, if the deposition is conducted by videoconference), and speak clearly and at a moderate pace. She should avoid mannerisms that may convey nervousness or uncertainty, such as touching her face, fidgeting with papers, or looking away from the questioner when answering. She should feel free to ask for breaks as needed — the Federal Rules permit reasonable breaks during a deposition — and should not hesitate to request a break if she feels fatigued or if she needs to use the restroom. However, she should avoid requesting breaks at moments that could appear strategic (e.g., immediately after a difficult question has been asked but before she has answered).

III. ANTICIPATED LINES OF CROSS-EXAMINATION

The following sections address, topic by topic, the lines of cross-examination we anticipate HVC will pursue during Dr. Ashford's deposition. For each topic, we identify the likely questions, the key documents that may be used, and recommended approaches and pitfalls to avoid. This analysis is based on our review of HVC's litigation strategy to date, the issues raised in the pleadings and discovery, the claim construction proceedings, and our general experience with HVC counsel in other patent cases.

A. Qualifications and Bias

1. Expert Credentials and Background

Opposing counsel will begin, as is customary, by exploring Dr. Ashford's qualifications. While this portion of the deposition may appear routine, it serves several strategic purposes for HVC: (1) establishing the boundaries of Dr. Ashford's expertise for possible Daubert challenge purposes; (2) identifying areas where Dr. Ashford's academic background may be contrasted with real-world industry experience; and (3) setting a cooperative tone for later, more adversarial questioning.

We expect HVC to probe the scope of Dr. Ashford's academic and industry experience in silicon photonics, with particular emphasis on whether she has hands-on design experience with commercial transceiver modules — as opposed to academic research conducted in a university laboratory setting. The distinction between academic research and commercial product development is one that HVC will likely seek to exploit throughout the deposition, and Dr. Ashford should be prepared to explain how her academic research experience, combined with her consulting engagements and her review of the technical literature, gives her a comprehensive understanding of the technology at issue, including its commercial implementation.

Specifically, we expect questions about Dr. Ashford's publication record, including her body of peer-reviewed articles and conference papers. HVC may focus on particular sub-topics — for instance, whether Dr. Ashford has published on waveguide multiplexers specifically, whether she has published on thermal management of photonic integrated circuits, and whether she has published on polarization-diverse grating couplers. Each of these sub-topics corresponds to one or more of the patents-in-suit, and HVC may attempt to argue that Dr. Ashford's expertise is stronger in some areas than in others. Dr. Ashford should be prepared to discuss her publication record honestly and to explain how her broader expertise in silicon photonics provides a sufficient foundation for her opinions even in sub-areas where her publication record may be thinner.

HVC may also attempt to contrast Dr. Ashford's academic background with the industry-specific expertise of their own expert, Dr. Rajesh Sundaram, who holds the position of Professor of Electrical & Computer Engineering at Pacific Western University in San Diego, California. If HVC raises this comparison, Dr. Ashford should avoid being drawn into a direct comparison of credentials. She should simply confirm her own qualifications and express her opinions based on her own independent analysis, without commenting on Dr. Sundaram's qualifications or the merits of his opinions. Any direct engagement with Dr. Sundaram's qualifications risks appearing defensive or, worse, providing testimony that HVC could use to frame a favorable comparison for their own expert.

2. Compensation and Engagement History

HVC will inevitably explore Dr. Ashford's financial arrangement with C&H and with OWS. This line of questioning is designed to suggest that Dr. Ashford's opinions may be influenced by the compensation she receives for her work. While this is a standard line of attack against expert witnesses and is unlikely to carry significant weight with the Court or a jury on its own, it can be effective if the expert appears defensive or evasive about the financial details.

Dr. Ashford's retention agreement with C&H, dated August 1, 2024, provides for an hourly rate of $950 per hour, with an estimated total budget for Dr. Ashford's engagement of approximately $1.1 million. HVC will likely ask Dr. Ashford to confirm her hourly rate, the total number of hours she has billed to date, and the total amount of fees she has received. Dr. Ashford should be prepared to provide these figures accurately. If she does not have the precise figures at the time of the deposition, she should say so and provide her best estimate, making clear that it is an estimate.

HVC will also explore Dr. Ashford's prior expert engagements — both for C&H and for OWS, and for other law firms and parties in other cases. Dr. Ashford should be prepared to confirm or deny prior engagements and to state what percentage of her professional income is derived from expert witness work as opposed to her academic salary, research grants, and other sources. If a substantial portion of her income derives from expert witness work, HVC will argue this creates a financial incentive to provide favorable opinions. Dr. Ashford should respond to this line of questioning straightforwardly and without defensiveness.

The recommended response to any question designed to suggest financial bias is as follows: Dr. Ashford's opinions are based on her independent technical analysis of the patents, the accused products, the prior art, and the relevant technical literature. Her opinions would be the same regardless of who retained her or which side of the case she was asked to evaluate. Her compensation is based on the time she expends on her analysis, not on the outcome of the case. She has not been promised any bonus or additional compensation contingent on the outcome, and her retention agreement contains no such provision.

3. Relationship with Optiwave or Counsel

HVC will ask whether Dr. Ashford has any prior consulting, research, or advisory relationship with OWS or any of its employees, including Dr. Jian-Wei Huang (OWS's Chief Technology Officer) and Dr. Nikolai Petrov (Vice President of Engineering, Photonics Division). HVC will also ask whether Dr. Ashford has any prior relationship with Cascade IP Advisors, LLC, the patent prosecution firm that prosecuted the patents-in-suit, or with Dr. Martin Chu, a principal at that firm.

Dr. Ashford should answer these questions truthfully and completely. If there are any prior relationships — even casual or tangential ones, such as co-attendance at a conference, mutual acquaintance through a professional organization, or a brief consulting engagement years ago — Dr. Ashford should disclose them. An undisclosed relationship that is later discovered will be far more damaging to credibility than a relationship that is disclosed and explained.

HVC will also ask whether Dr. Ashford reviewed any privileged communications between OWS and its counsel, or received any legal conclusions or legal instructions from C&H. Dr. Ashford should confirm that she did not receive legal conclusions from counsel and that her opinions are her own. To the extent she received facts, data, or technical materials from counsel, that is standard practice for expert witness engagements and is entirely proper. If the questioning ventures into the substance of privileged communications, C&H counsel will assert the privilege.

B. Person of Ordinary Skill in the Art (POSITA) Definition

1. Dr. Ashford's POSITA Definition

The definition of a person of ordinary skill in the art is foundational to both the infringement analysis and the validity analysis. Dr. Ashford has defined a POSITA consistently across her Opening Claim Construction Declaration (submitted November 15, 2024) and both of her expert reports (served June 15, 2025). Her definition provides that a POSITA in this field would be a person holding a Master of Science (M.S.) or Doctor of Philosophy (Ph.D.) degree in electrical engineering or photonics, with at least three years of experience in silicon-photonic integrated circuit design.

We expect HVC to challenge this definition from multiple angles, depending on which claim construction or validity issue is at stake. In some contexts, HVC may argue that the POSITA definition is too narrow — for example, that it excludes individuals with equivalent practical experience but without formal graduate degrees, or that it excludes individuals with degrees in related fields such as materials science or applied physics. In other contexts, HVC may argue that the POSITA definition is too broad — for example, that it should require specialized experience in coherent optical communication systems (relevant to the '193 Patent) or in thermal management of integrated circuits (relevant to the '562 Patent).

Dr. Ashford should be prepared to defend her POSITA definition on its merits. The definition is grounded in the level of sophistication reflected in the patent specifications themselves — the patents use technical terminology and describe fabrication processes and design choices that would be understood by a person with the defined educational background and experience level. The definition is also consistent with the level of skill reflected in the prior art cited during prosecution, which includes academic journal articles, conference papers, and patents authored by individuals with comparable credentials. If pressed, Dr. Ashford can point to specific passages in the patent specifications and in the prior art that illustrate the level of technical knowledge assumed by the relevant literature.

Dr. Sundaram, Lumicore's expert, may have proposed a different POSITA definition — likely one requiring more industry-specific design experience, a different number of years of experience, or different educational qualifications. If Dr. Ashford is aware of Dr. Sundaram's definition (e.g., from his declaration submitted during claim construction on December 6, 2024), she should be prepared to explain why her definition is more appropriate and consistent with the state of the art at the time of each patent's filing. However, she should avoid directly criticizing Dr. Sundaram's definition in a manner that appears personal or adversarial; a calm, technical explanation of why her own definition is well-founded is more effective than a point-by-point attack on the competing definition.

2. Impact of POSITA Definition on Claim Construction and Validity

HVC will probe whether changing the POSITA definition would alter Dr. Ashford's opinions on the ordinary and customary meaning of the disputed claim terms. This line of questioning is designed to show that Dr. Ashford's infringement and validity opinions are sensitive to the POSITA definition and could change under a different definition — thereby suggesting that the opinions are fragile or result-oriented.

There are currently 14 disputed claim terms in this case, 12 of which remain in dispute following the agreement of the parties on two terms during the claim construction briefing. The 12 remaining disputed terms include, among others, "waveguide multiplexer" (from the '847 Patent), "integrated on a silicon substrate" (from the '193 Patent), "micro-channel heat sink" (from the '562 Patent), and "polarization-diverse grating coupler" (from the '015 Patent). For each of these terms, Dr. Ashford should be prepared to explain how her POSITA definition informs her understanding of the term's ordinary and customary meaning.

Of particular focus will be the term "integrated on a silicon substrate" from the '193 Patent. HVC will likely argue that a POSITA with more industry experience — for example, five or more years of experience in commercial transceiver design — would understand this term to require monolithic fabrication on a single silicon die, consistent with Lumicore's proposed claim construction. Under Lumicore's construction, the term excludes devices fabricated using hybrid bonding or heterogeneous integration techniques. OWS's broader construction — "formed on or within a silicon-based wafer using semiconductor fabrication processes" — encompasses both monolithic fabrication and hybrid integration approaches. Dr. Ashford should be prepared to explain why a POSITA with the credentials she has defined would understand the term in the broader sense, drawing on the patent specification's description of the fabrication process and the state of the art at the time of filing.

3. POSITA Knowledge and State of the Art

HVC will ask Dr. Ashford to describe what a POSITA would have known at the time of each patent's effective filing date. This line of questioning is relevant both to claim construction (the ordinary and customary meaning of claim terms is assessed from the perspective of a POSITA at the time of filing) and to validity (the obviousness inquiry is based on the state of the art at the time of filing). The relevant filing dates are as follows:

Dr. Ashford should be prepared to discuss the evolution of silicon-photonics technology during the period from 2014 through 2019 and to explain how a POSITA's understanding of key terms and technologies may or may not have changed over that period. For example, the use of hybrid bonding and heterogeneous integration techniques became more common in the later part of this period, which is relevant to the construction of "integrated on a silicon substrate." Similarly, the understanding of thermal management challenges in photonic integrated circuits evolved as power densities increased with higher data rates. Dr. Ashford should be able to place each patent in its technological context and explain what would have been known, what would have been novel, and what would have been non-obvious to a POSITA at each relevant date.

C. Infringement Opinions — Literal Infringement

1. '847 Patent (U.S. 10,234,847) — "Multi-Channel Silicon Photonic Waveguide Multiplexer with Low Insertion Loss"

The '847 Patent is directed to a multi-channel silicon photonic waveguide multiplexer designed to achieve low insertion loss, a critical performance parameter for optical communication systems. The asserted claims are Claims 1, 3, 5, 9, and 14. The accused products are the LumiLink 400G-ZR+ and the LumiLink 800G-DR8.

The key disputed claim term for this patent is "waveguide multiplexer." OWS proposes that this term should be construed to mean "an optical device that combines multiple optical signals of different wavelengths onto a single waveguide." Lumicore proposes a substantially narrower construction: "an arrayed waveguide grating that combines optical signals using a slab coupler and phase-shifted waveguide array." The difference between these constructions is significant. Under OWS's broader construction, any multiplexing architecture — including arrayed waveguide gratings (AWGs), Mach-Zehnder interferometer (MZI)-based designs, ring-resonator-based designs, and other architectures — would fall within the claim scope. Under Lumicore's narrower construction, only AWG-based multiplexers would infringe.

HVC will conduct a detailed element-by-element examination of each asserted claim, focusing on whether Lumicore's accused products use an AWG architecture (which would satisfy both parties' constructions) or a different multiplexing architecture (e.g., an MZI-based or ring-resonator-based design) that would satisfy only OWS's broader construction. Dr. Ashford should be intimately familiar with the architecture of the accused products as revealed by the Benchmark teardown reports and Lumicore's own design files, and she should be prepared to identify the specific structures in the accused products that correspond to each claim limitation.

Dr. Ashford should be prepared to walk through the Benchmark Semiconductor Analysis, LLC teardown report for the LumiLink 400G-ZR+ (delivered December 12, 2022, by Kevin Ng, Lead Engineer) and the follow-on teardown report for the LumiLink 800G-DR8 (completed June 2023). For each accused product, she should be able to identify the specific physical structures observed in the teardown — including waveguide geometries, coupler architectures, grating structures, and metallization layers — and explain how those structures correspond to each element of each asserted claim. She should be comfortable referring to specific figures, photographs, and SEM images from the teardown reports to support her testimony.

With respect to Claim 9, C&H's internal analysis (dated October 5, 2024) identified a potentially means-plus-function limitation in this claim. Under 35 U.S.C. § 112(f), a means-plus-function limitation is construed to cover the corresponding structure, material, or act described in the patent specification, and equivalents thereof. Dr. Ashford should be prepared to identify the corresponding structure in the '847 Patent specification that performs the claimed function and to explain how the structure in the accused product either is that structure or is an equivalent of that structure. This analysis is set forth in her Infringement Report, and she should be prepared to walk through it step by step.

HVC may also raise claim differentiation arguments with respect to the relationship between independent Claim 1 and dependent Claims 3 and 5. Specifically, HVC may argue that because dependent Claims 3 and 5 add limitations to Claim 1 that relate to specific structural features of the multiplexer, independent Claim 1 should be construed narrowly to exclude those features — otherwise, the argument goes, the dependent claims would be superfluous. Dr. Ashford should be prepared to explain why the claim-differentiation doctrine actually supports a broader construction of Claim 1. The doctrine creates a presumption that dependent claims add meaningful limitations to the independent claim, but it does not require that the independent claim be construed so narrowly as to exclude the subject matter of the dependent claims. Rather, the dependent claims narrow the scope of the independent claim by adding additional requirements; the independent claim, by definition, does not include those additional requirements and is therefore broader.

2. '193 Patent (U.S. 10,891,193) — "High-Bandwidth Coherent Optical Transceiver Integrated on Silicon Substrate"

The '193 Patent is directed to a high-bandwidth coherent optical transceiver integrated on a silicon substrate. It is the broadest of the four asserted patents in terms of the number of asserted claims (Claims 1, 3, 7, 10, 15, and 18) and accused products (all three Lumicore products — the LumiLink 400G-ZR+, the LumiLink 800G-DR8, and the LumiEdge 1600G-LR).

The key disputed terms for this patent are "integrated on a silicon substrate" and the "coherent detection module" limitation. These terms are central to both the literal-infringement analysis and the doctrine-of-equivalents analysis, and they will receive substantial attention during the deposition.

With respect to "integrated on a silicon substrate," OWS proposes the construction "formed on or within a silicon-based wafer using semiconductor fabrication processes," while Lumicore proposes "monolithically fabricated on a single silicon die without hybrid bonding or heterogeneous integration." The practical significance of this dispute is substantial: if the Court adopts Lumicore's narrow construction, the infringement analysis depends on whether the accused products are monolithically fabricated or instead use hybrid bonding or heterogeneous integration techniques to combine multiple semiconductor dies or materials on a single substrate.

Dr. Ashford must be prepared to testify about the fabrication methodology of each accused product. If the evidence indicates that one or more accused products use hybrid bonding — and there are indications from the Benchmark teardown data and from Lumicore's design files that certain accused products may incorporate hybrid-bonded III-V semiconductor laser sources on a silicon photonic platform — then the literal-infringement analysis under Lumicore's narrow construction would fail for those products. In that event, the infringement theory would depend on the doctrine of equivalents analysis set forth in Appendix B of Dr. Ashford's Infringement Report. Dr. Ashford should be prepared to explain how the DOE analysis addresses this gap, using the function-way-result framework discussed in Section III.D below.

With respect to Claim 15, C&H's internal analysis (October 5, 2024) identified a potentially means-plus-function limitation. As with Claim 9 of the '847 Patent, Dr. Ashford should be prepared to identify the corresponding structure in the '193 Patent specification and to explain how the accused products satisfy this limitation.

Importantly, the Markman hearing in this case occurred on March 14, 2025, before Judge James R. Gilstrap. Dr. Ashford's expert reports were drafted in light of the Court's claim construction ruling, and her opinions should be fully consistent with the Court's adopted constructions. HVC will scrutinize the reports for any inconsistency with the Markman order. Dr. Ashford should be prepared to confirm that her opinions are consistent with the Court's rulings and, if necessary, to explain how any aspect of her analysis was adjusted between her pre-Markman claim construction declaration (November 15, 2024) and her post-Markman expert report (June 15, 2025) to conform to the Court's constructions.

3. '562 Patent (U.S. 9,678,562) — "Method for Thermal Management of Photonic Integrated Circuits Using Embedded Micro-Channel Heat Sinks"

The '562 Patent is directed to a method for thermal management of photonic integrated circuits using embedded micro-channel heat sinks. The asserted claims are Claims 1, 4, 6, and 11, and the accused products are the LumiLink 400G-ZR+ and the LumiLink 800G-DR8.

The key disputed claim term for this patent is "micro-channel heat sink." OWS proposes the construction "a heat-dissipating structure containing channels with a hydraulic diameter of less than 1 mm." Lumicore proposes a substantially narrower construction: "a closed-loop liquid-cooling system with channels having a hydraulic diameter between 10 µm and 200 µm." The difference between these constructions is twofold: (1) OWS's construction does not require a closed-loop liquid-cooling system (it would encompass passive heat-dissipating structures as well as active liquid-cooling systems), whereas Lumicore's construction requires a closed-loop liquid-cooling system; and (2) the dimensional ranges differ — OWS's construction requires only that the hydraulic diameter be less than 1 mm, while Lumicore's construction requires the hydraulic diameter to be between 10 µm and 200 µm.

C&H has identified this patent as having the strongest literal-infringement case among the four asserted patents. The Benchmark teardown data clearly identified micro-channel structures in the accused products, and the measured channel dimensions fall squarely within the range claimed by both parties' proposed constructions. Accordingly, this is the patent for which the infringement analysis is most straightforward, and we anticipate that HVC's cross-examination will be more focused on validity and claim construction than on the element-by-element infringement mapping.

Nevertheless, Dr. Ashford should be prepared to explain in detail the teardown methodology used by Kevin Ng of Benchmark Semiconductor Analysis, LLC. She should be able to describe the general process of obtaining and preserving the accused product samples (chain of custody), the cross-sectioning technique used to expose the internal structures of the photonic integrated circuit, the scanning electron microscopy (SEM) imaging used to photograph the micro-channel structures, and the dimensional measurements taken from the SEM images. She should be prepared to explain how the measured channel dimensions of the accused products fall within the claimed range under any reasonable construction of "micro-channel heat sink."

An additional area of anticipated questioning relates to the provenance of the '562 Patent. This patent was originally assigned to Solara Optics, Inc. and was subsequently acquired by OWS pursuant to an Asset Purchase Agreement ("APA") dated June 15, 2018, for a total consideration of $34.5 million covering a portfolio of 12 patents (including the '562 Patent). HVC may probe Dr. Ashford's knowledge of the patent's provenance, any differences between the patent application as originally filed by Solara and the claims as ultimately issued, and whether any changes to the claims during prosecution affect the scope of the asserted claims or the infringement analysis. Dr. Ashford should be prepared to confirm that she is aware the patent was acquired from Solara but that her infringement analysis is based on the patent as issued, regardless of its ownership history. She should defer to counsel on any questions relating to the terms of the APA or the business rationale for the acquisition.

4. '015 Patent (U.S. 11,402,015) — "Polarization-Diverse Grating Coupler for Silicon Photonic Transceivers"

The '015 Patent is directed to a polarization-diverse grating coupler for silicon photonic transceivers. The asserted claims are Claims 1, 5, 8, 12, and 16, and the accused products are the LumiLink 800G-DR8 and the LumiEdge 1600G-LR.

The key disputed claim term for this patent is "polarization-diverse grating coupler." OWS proposes the construction "a grating coupler capable of coupling light of two orthogonal polarization states." Lumicore proposes the narrower construction "a two-dimensional grating coupler with a polarization-splitting element that simultaneously couples TE and TM modes." The difference is significant: OWS's broader construction would encompass grating couplers that handle orthogonal polarization states sequentially or in separate channels, as well as those that handle them simultaneously, whereas Lumicore's construction requires simultaneous coupling of both TE (transverse electric) and TM (transverse magnetic) modes through a two-dimensional grating with a dedicated polarization-splitting element.

An additional key limitation relevant to this patent is the "two-dimensional sub-wavelength grating" element recited in Claim 12. This limitation is the subject of a doctrine-of-equivalents analysis in Dr. Ashford's Infringement Report (Appendix B), as discussed in Section III.D below. The construction and scope of this limitation are particularly important because a narrowing amendment was made to this limitation during prosecution.

The '015 Patent shares a common provisional application — Provisional Application No. 62/499,117, filed April 7, 2017 — with the '193 Patent. This means that the two patents share the same priority date for claims that are supported by the provisional application, and the prosecution histories of the two patents are interrelated. Dr. Ashford should be prepared to discuss this relationship and to explain how the two patents cover different aspects of the same underlying technology — the '193 Patent covering the broader transceiver architecture and the '015 Patent covering the specific grating coupler design used in the transceiver's input/output interface.

Dr. Ashford should be prepared to explain how the accused products' grating coupler designs satisfy the claim limitations of the '015 Patent, with reference to Benchmark's February 2024 teardown of the LumiEdge 1600G-LR. The LumiEdge 1600G-LR teardown is the most recent of the three teardown reports and contains detailed SEM imagery of the grating coupler structures, including cross-sectional views showing the grating periodicity, fill factor, and etch depth, as well as top-down views showing the two-dimensional pattern of the grating. Dr. Ashford should be comfortable identifying these features in the teardown images and explaining their correspondence to the claimed limitations.

D. Doctrine of Equivalents (DOE) — Critical Area

1. Scope of DOE Contentions

The doctrine of equivalents is a judicially created doctrine that extends patent protection beyond the literal scope of the claims to encompass equivalents that perform substantially the same function, in substantially the same way, to achieve substantially the same result as the claimed limitation. OWS's infringement contentions include DOE claims for the following specific limitations:

• Claims 3 and 7 of the '193 Patent: Specifically, the "coherent detection module" limitation. Dr. Ashford's infringement analysis concluded that the accused products may not literally satisfy this limitation under certain claim constructions, but that the accused products' coherent receiver architecture performs substantially the same function, in substantially the same way, to achieve substantially the same result as the claimed "coherent detection module."

• Claim 12 of the '015 Patent: Specifically, the "two-dimensional sub-wavelength grating" limitation. Dr. Ashford's analysis concluded that the accused products' grating structures, while differing in certain respects from the literal claim language (as narrowed during prosecution), are equivalent to the claimed limitation under the function-way-result test.

Dr. Ashford's Infringement Report includes Appendix B, which sets forth a detailed function-way-result analysis for each of these DOE contentions. This appendix identifies the specific differences between the claim elements and the corresponding elements in the accused products, and explains why those differences are insubstantial under the equivalents test. Dr. Ashford should review Appendix B thoroughly before the deposition and should be prepared to articulate the analysis from memory, without needing to refer to the written report.

2. Function-Way-Result Analysis

For each DOE contention, HVC will probe each prong of the function-way-result test in detail. We anticipate that HVC will structure this examination as follows:

Function: HVC will ask Dr. Ashford to identify the function performed by the claim element (e.g., the "coherent detection module" limitation) and the function performed by the corresponding element in the accused product. HVC will then ask whether these functions are substantially the same. Dr. Ashford should be prepared to articulate the function clearly and specifically — not at an overly high level of abstraction (which could vitiate the limitation) and not at an overly granular level (which could create artificial distinctions between the claim element and the accused element).

Way: HVC will ask Dr. Ashford to describe the manner in which the claim element performs its function and the manner in which the accused element performs its function. This is often the most contested prong of the analysis, because it requires a detailed comparison of the technical mechanisms employed by the claim element and the accused element. HVC will attempt to elicit testimony that the accused element operates in a fundamentally different way from the claim element, which would defeat the DOE theory. Dr. Ashford should be prepared to explain, with technical specificity, why the "way" employed by the accused element is substantially the same as the "way" employed by the claim element, even if there are superficial differences in implementation.

Result: HVC will ask Dr. Ashford to identify the result achieved by the claim element and the result achieved by the accused element, and whether these results are substantially the same. This prong is often the most straightforward, but Dr. Ashford should not treat it as a mere formality — she should articulate the result clearly and explain why the accused element achieves substantially the same result.

Throughout this examination, HVC will attempt to elicit admissions that the accused elements differ from the claim elements in some material respect. Dr. Ashford should not resist acknowledging differences where they exist — the entire premise of the DOE analysis is that there are differences between the claim language and the accused product. The question is not whether differences exist (they do, by definition, or the analysis would be one of literal infringement), but whether those differences are insubstantial. Dr. Ashford should acknowledge the differences candidly and then explain, with technical specificity, why those differences are insubstantial under the equivalents test.

3. Prosecution History Estoppel (Festo)

This is expected to be a major focus of cross-examination, and it represents one of the most significant areas of vulnerability in OWS's infringement case.

Under Festo Corp. v. Fenmore & Co., 535 U.S. 722 (2002), when a patent applicant narrows a claim during prosecution to secure the patent, there is a presumption that the applicant surrendered the territory between the original claim and the amended claim. This "Festo presumption" bars the application of the doctrine of equivalents to recapture the surrendered territory, unless one of three exceptions applies: (1) the equivalent at issue was unforeseeable at the time of the amendment; (2) the rationale underlying the amendment bears no more than a tangential relation to the equivalent at issue; or (3) there is some other reason suggesting that the patentee could not reasonably have been expected to have drafted a claim that literally encompassed the equivalent.

Both DOE contentions in this case are subject to Festo analysis because the relevant claim limitations were narrowed during prosecution:

'193 Patent — Claims 3 and 7 ("coherent detection module"): During prosecution of the '193 Patent, the "coherent detection module" limitation was narrowed in response to a rejection under 35 U.S.C. § 102 (anticipation) based on the Takahashi et al. reference ("Dense WDM Silicon Photonic MUX," IEEE Photonics Technology Letters, March 2014). The original claim language described the coherent detection module in broader terms, and the applicant amended the claim to add specific structural or functional requirements to distinguish Takahashi. C&H's internal Prosecution History Estoppel Analysis, dated October 10, 2024, assessed the impact of this amendment on the DOE theory.

Dr. Ashford must be prepared to explain the following three elements of this analysis:

(a) The nature of the amendment: What was the original claim language? What was the amended claim language? What was added, removed, or modified?

(b) Why the amendment was made: The amendment was made in response to the examiner's specific rejection based on Takahashi. The examiner found that Takahashi disclosed the original claim language, and the applicant narrowed the claim to distinguish Takahashi's specific disclosure. The amendment was directed at a particular feature of Takahashi — not at the general concept of coherent detection.

(c) Whether the Festo exception applies: Specifically, whether the equivalent at issue in the accused products is tangential to the reason the amendment was made. The argument is that the narrowing amendment was made to distinguish a specific feature of Takahashi that is different from the feature present in Lumicore's accused products. The equivalent found in Lumicore's products relates to a different aspect of the coherent detection module — one that was not the basis for the examiner's rejection and was not the reason for the narrowing amendment.

Key pitfall: If Dr. Ashford characterizes the amendment as directly related to the specific equivalent at issue in the accused products, it could undermine the entire DOE theory for Claims 3 and 7 of the '193 Patent. She should be prepared to explain, with reference to the prosecution history, why the narrowing amendment was directed at distinguishing a specific feature of Takahashi that is different from the feature present in Lumicore's accused products. This requires a precise understanding of both the Takahashi reference and the accused products' coherent detection architecture.

'015 Patent — Claim 12 ("two-dimensional sub-wavelength grating"): During prosecution of the '015 Patent, a narrowing amendment was made to the "two-dimensional sub-wavelength grating" limitation in order to overcome a rejection under 35 U.S.C. § 103 (obviousness) based on a combination of the Bergmann patent (U.S. 8,412,007, issued April 2, 2013) and the Simonsen PCT application (PCT/EP2015/071234, filed September 17, 2015). C&H's internal Prosecution History Estoppel Analysis, dated October 12, 2024, evaluated this amendment.

The Festo analysis for this claim follows a similar structure. Dr. Ashford should be prepared to explain the nature of the amendment, the reason it was made (to overcome the examiner's § 103 rejection based on the specific combination of Bergmann and Simonsen), and why one of the Festo exceptions applies. In this case, either the tangential-relation exception or the unforeseeability exception may apply. The tangential-relation exception would apply if the reason for the amendment (distinguishing the Bergmann/Simonsen combination) bears no more than a tangential relation to the equivalent found in Lumicore's accused products. The unforeseeability exception would apply if the particular equivalent used by Lumicore was not foreseeable at the time of the amendment — for example, if the technology used by Lumicore was not commercially available or known in the art at the time of prosecution.

HVC will likely walk through the prosecution history in meticulous detail, showing Dr. Ashford the original claim language, the examiner's rejection, and the amended claim language side by side. HVC will then ask Dr. Ashford to identify precisely what territory was surrendered by the amendment and to explain how the equivalent in the accused product falls outside the surrendered territory. This is a technically demanding line of questioning, and Dr. Ashford should prepare for it extensively during the practice sessions described in Section VII below.

4. Vitiation / All-Limitations Rule

In addition to prosecution history estoppel, HVC may argue that applying the doctrine of equivalents to certain claim limitations would effectively "vitiate" those limitations — that is, it would render the limitation meaningless by allowing it to be satisfied by any structure, regardless of how different it is from the claimed element. This argument is related to the "all-limitations rule," which requires that each element of a claim be present in the accused product, either literally or equivalently. Under this rule, the doctrine of equivalents cannot be applied in a manner that effectively reads a claim limitation out of the claim.

Dr. Ashford should be prepared to explain why her DOE analysis respects the all-limitations rule. For each DOE contention, the equivalent element in the accused product still corresponds to a specific, identifiable claim limitation — it is not broader than the claimed limitation, and it does not render the limitation superfluous. The accused element performs the same function, in the same way, to achieve the same result — it is merely a different specific implementation of the same technical concept. The existence of differences between the claim element and the accused element is what necessitates the DOE analysis in the first place; those differences do not vitiate the claim limitation unless they are so fundamental as to render the claim element meaningless.

E. Validity Opinions — Rebuttal of Invalidity Contentions

1. Overview. Lumicore's invalidity contentions, served on October 14, 2024, cite 23 prior-art references across all four asserted patents. These references include academic journal articles, conference papers, patents, patent applications, and internal Lumicore design documents. The invalidity contentions assert both anticipation under 35 U.S.C. § 102 and obviousness under 35 U.S.C. § 103 against various claims of each asserted patent.

Dr. Ashford's Validity Report, served on June 15, 2025, addresses each of the 23 references and opines that none anticipates or renders obvious any asserted claim of any of the four patents-in-suit. Her report includes Appendix A, which contains detailed claim charts for each of the 23 references, demonstrating the specific claim limitations that each reference fails to disclose and the specific features that distinguish the claimed inventions from the prior art.

HVC will cross-examine Dr. Ashford on her validity opinions with the goal of establishing that one or more of the prior-art references does in fact anticipate or render obvious the asserted claims. The examination will likely focus on the references that HVC considers its strongest invalidity arguments, which we have identified based on the invalidity contentions and the discovery to date. The key references are discussed below.

2. Key Prior-Art References — Anticipated Focus

a. Takahashi et al. — '847 Patent Anticipation (§ 102). The Takahashi reference is "Dense WDM Silicon Photonic MUX," published in IEEE Photonics Technology Letters in March 2014. HVC will argue that this reference discloses all elements of one or more of the asserted claims of the '847 Patent, rendering those claims anticipated under § 102.

Dr. Ashford should be prepared to walk through her claim chart for Takahashi (in Appendix A of her Validity Report) and to identify the specific claim limitations that Takahashi does not disclose. She should also be prepared to explain any features that Takahashi teaches away from — that is, any aspects of the reference that affirmatively discourage a POSITA from arriving at the claimed invention. For anticipation, the standard is strict: a single reference must disclose each and every element of the claim, arranged as in the claim. If even one element is missing, the anticipation argument fails. Dr. Ashford should identify the missing elements clearly and specifically.

We note that Takahashi is also relevant to the prosecution history estoppel analysis for the '193 Patent (see Section III.D.3 above), as it was the reference cited in the § 102 rejecti

MEMORANDUM
PRIVILEGED AND CONFIDENTIAL — ATTORNEY WORK PRODUCT
THIS MEMORANDUM IS PROTECTED BY THE ATTORNEY-CLIENT PRIVILEGE AND THE WORK PRODUCT DOCTRINE. IT HAS BEEN PREPARED IN ANTICIPATION OF LITIGATION AND REFLECTS THE MENTAL IMPRESSIONS, CONCLUSIONS, AND LEGAL THEORIES OF COUNSEL. THIS MEMORANDUM IS NOT TO BE DISCLOSED TO ANY THIRD PARTY WITHOUT THE EXPRESS WRITTEN CONSENT OF CALDERWOOD & HARKNESS LLP.
TO: Dr. Caroline Ashford, Professor of Electrical Engineering & Photonics, Northfield Institute of Technology, Evanston, IL
FROM: Alan Ngo, Responsible Partner; Wendy Schultz, Lead Associate; Omar Siddiqui, Working Associate — Calderwood & Harkness LLP
DATE: July 21, 2025
RE: Deposition Preparation — Optiwave Semiconductor Corp. v. Lumicore Technologies, Inc., Case No. 2:24-cv-00319-JRG (E.D. Tex.)
SUBJECT: Preparation for Expert Deposition of Dr. Caroline Ashford by Hawthorne Vega & Cruz LLP
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I. PURPOSE AND SCOPE OF THIS MEMORANDUM
This memorandum has been prepared by Calderwood & Harkness LLP ("C&H") to assist Dr. Caroline Ashford in preparing for her upcoming deposition in the above-referenced matter. The deposition is anticipated to be taken by Hawthorne Vega & Cruz LLP ("HVC"), counsel for Defendant Lumicore Technologies, Inc. ("Lumicore"). Based on our assessment of opposing counsel's litigation team, we anticipate that the deposition will be conducted by lead partner Catherine "Kate" Rourke and/or second chair partner Darren Cho, both of whom have substantial experience in complex patent litigation and are skilled cross-examiners.
The deposition is expected to be scheduled in late July or early August 2025. This timing follows the service of Dr. Ashford's two expert reports on June 15, 2025, and falls before the expert discovery close date of August 15, 2025, as set by the Court's Scheduling Order (Docket Entry ("D.E.") 22, entered August 12, 2024). Accordingly, we must use the intervening weeks to prepare thoroughly for what we anticipate will be an extensive and technically rigorous cross-examination.
As a preliminary matter, Dr. Ashford has submitted two expert reports on behalf of Plaintiff Optiwave Semiconductor Corp. ("OWS"):
(1) Expert Report on Infringement — In this report, Dr. Ashford opines that each of the accused Lumicore products — specifically, the LumiLink 400G-ZR+, the LumiLink 800G-DR8, and the LumiEdge 1600G-LR — infringes each asserted claim of U.S. Patent Nos. 10,234,847 (the "'847 Patent"), 10,891,193 (the "'193 Patent"), 9,678,562 (the "'562 Patent"), and 11,402,015 (the "'015 Patent"), both literally and under the doctrine of equivalents where applicable.
(2) Expert Report on Validity — In this report, Dr. Ashford rebuts Lumicore's invalidity contentions, which were served on October 14, 2024, and which address all 23 prior-art references cited by Lumicore across the four asserted patents. Dr. Ashford opines that none of the cited prior-art references, individually or in combination, anticipates or renders obvious any asserted claim of any of the four patents-in-suit.
This memorandum is organized to address the following topics in sequence, each of which is discussed at length in the sections that follow:
(a) General deposition guidance, including format, logistics, and principles of demeanor;
(b) Anticipated lines of cross-examination, organized by topic and by patent, including qualifications and bias, person of ordinary skill in the art ("POSITA") definition, literal infringement, doctrine of equivalents, prosecution history estoppel, validity opinions, and reliance on Benchmark Semiconductor Analysis, LLC data;
(c) Key documents that Dr. Ashford should review and be prepared to discuss during the deposition;
(d) Recommended responses and pitfalls to avoid on each major topic;
(e) Areas requiring particular care, including the doctrine of equivalents analysis for the '193 and '015 Patents, prosecution history estoppel under Festo Corp. v. Fenmore & Co., 535 U.S. 722 (2002), the POSITA definition and its implications for both infringement and validity, and the extent and nature of Dr. Ashford's reliance on the Benchmark Semiconductor Analysis, LLC teardown data.
We emphasize that this memorandum reflects counsel's litigation strategy, mental impressions, and assessment of the strengths and weaknesses of particular arguments. Its contents should not be disclosed to any third party, and Dr. Ashford should not reference this memorandum or its contents during the deposition itself. If asked about communications with counsel, Dr. Ashford should defer to the assertion of privilege by C&H attorneys present at the deposition.
II. GENERAL DEPOSITION GUIDANCE
A. Deposition Format and Logistics
Dr. Ashford's deposition will be taken pursuant to Federal Rule of Civil Procedure 30 and the applicable local rules of the Eastern District of Texas. We anticipate that HVC will notice the deposition for the presumptive limit of seven hours of examination in a single day, although it is possible that HVC may seek leave of Court to extend the duration given that Dr. Ashford submitted two separate expert reports addressing both infringement and validity. In the event that HVC moves for additional time, we will evaluate whether to oppose that motion or to stipulate to a reasonable extension. Dr. Ashford should plan for the possibility of a full day of examination and should not schedule other commitments for the day immediately following the deposition in case of any overflow.
The location of the deposition has not yet been confirmed. Based on prior practice in this case, we expect HVC will designate either its Austin, Texas office at 600 Congress Avenue, Suite 2400, Austin, TX 78701, or will agree to conduct the deposition by videoconference. If the deposition is conducted in person in Austin, C&H will arrange travel and accommodations for Dr. Ashford. If it is conducted by videoconference, Dr. Ashford should plan to be located in a quiet, professional setting with reliable internet connectivity, a neutral background, and appropriate lighting. We will confirm the format and location once the deposition notice is received and will coordinate logistics at that time.
A court reporter will be present (or connected remotely) to create a stenographic transcript. We also expect HVC to retain a videographer to create a video recording of the deposition. Under Rule 30(b)(3)(A), HVC is entitled to record the deposition by video as well as by stenographic means, and we should assume that any video recording may be used at trial for impeachment purposes or as substantive evidence if Dr. Ashford is unavailable at trial (although we fully expect Dr. Ashford to testify live). The video recording means that Dr. Ashford's demeanor, body language, and tone will be preserved, which makes the guidance in Section II.C below all the more important.
C&H attorneys will attend the deposition. We anticipate that either Alan Ngo (Responsible Partner) or Wendy Schultz (Lead Associate) — or both — will be present and will assert objections on the record where appropriate. However, Dr. Ashford should understand the following important principle: she should not look to counsel for signals or guidance during questioning. Under the Federal Rules and the ethical rules governing depositions, counsel may assert objections (e.g., objections to form, privilege, and the like) but generally may not coach the witness. Dr. Ashford should pause briefly — approximately two to three seconds — after each question before beginning her answer. This pause serves two purposes: (1) it gives counsel the opportunity to assert any objection before Dr. Ashford answers; and (2) it gives Dr. Ashford time to consider the question carefully before responding. If an objection is asserted, Dr. Ashford should wait for counsel to complete the objection and then, unless instructed not to answer (which will occur only in rare circumstances, such as questions that implicate the attorney-client privilege), should proceed to answer the question as asked.
B. Core Deposition Principles
The following principles are foundational to effective deposition testimony. While Dr. Ashford is an experienced academic and has previously testified as an expert witness, we review these principles here because they bear repeating in the context of this particular case, where the technical complexity of the subject matter and the sophistication of opposing counsel create unique challenges.
Listen to the full question before answering; answer only the question asked. This is the single most important principle of deposition practice. Opposing counsel will craft their questions carefully, and Dr. Ashford should not begin formulating her answer until the question has been fully stated. Many witnesses — particularly expert witnesses who are deeply familiar with the subject matter — have a tendency to anticipate where a question is heading and to begin answering before the questioner has finished. This tendency should be resisted. A complete, carefully phrased question may differ materially from the question Dr. Ashford anticipated, and a premature answer may volunteer information that was not called for.
Do not volunteer information beyond the scope of the question. Dr. Ashford's natural inclination as an educator and researcher may be to provide thorough, comprehensive explanations. In a deposition, however, less is more. If a question can be answered with "yes" or "no," a one-word answer is generally appropriate, though Dr. Ashford may add a brief qualifier if a bare "yes" or "no" would be misleading. The key principle is that Dr. Ashford should answer the question that was asked — not the question she wishes had been asked, and not a broader question that would allow her to deliver a more complete explanation. There will be opportunities at trial to provide full explanations; the deposition is opposing counsel's examination, and its purpose is to gather information and lock in testimony, not to provide Dr. Ashford a platform for advocacy.
If a question is unclear, ask for clarification; do not guess at meaning. Opposing counsel may ask questions that are ambiguous, compound, or that use technical terms imprecisely. Dr. Ashford should not attempt to interpret an unclear question and answer based on her best guess of what was meant. Instead, she should ask the questioner to rephrase or clarify the question. Responses such as "Could you clarify what you mean by [term]?" or "I'm not sure I understand the question — could you rephrase it?" are entirely appropriate. This practice protects Dr. Ashford from having her answers taken out of context based on an interpretation of the question that differs from what she understood.
It is always acceptable to say "I don't know" or "I don't recall" if that is truthful. Dr. Ashford is under oath and is obligated to testify truthfully. If she does not know the answer to a question, she should say so. If she does not recall a particular fact, date, or conversation, she should say so. She should not speculate or guess in order to avoid these answers. There is no requirement that an expert witness have the answer to every question, and an honest "I don't know" is far more effective — and far less dangerous — than a speculative answer that may later prove incorrect.
Do not speculate; opinions should be grounded in the analysis set forth in the expert reports. Dr. Ashford's expert opinions are the opinions set forth in her two reports served on June 15, 2025. Opposing counsel may attempt to elicit opinions on topics that go beyond the scope of those reports — for example, by asking hypothetical questions or by asking Dr. Ashford to opine on issues she did not address. Unless the question calls for an opinion that is fairly within the scope of her reports, Dr. Ashford should decline to offer an opinion on the spot. Appropriate responses include: "I did not address that question in my report," "That is outside the scope of my analysis," or "I would need to review additional materials before offering an opinion on that topic."
Be aware that opposing counsel may attempt to establish friendly rapport, then shift to adversarial questioning. This is a common and effective deposition technique. The questioner begins with easy, non-threatening questions — biographical background, general descriptions of the technology, areas where the experts may agree — to put the witness at ease and establish a pattern of agreeable answers. Then, once the witness has relaxed into a pattern of conceding points, the questioner transitions to substantive and contested issues, hoping to carry forward the witness's cooperativeness into areas where concessions are harmful. Dr. Ashford should maintain a consistent demeanor throughout the deposition — polite, professional, and measured — regardless of whether the questioning feels friendly or adversarial.
Avoid absolute statements ("always," "never") unless the technical basis is unambiguous. Absolute statements are easy to attack on cross-examination and can be used to undermine credibility if even a single exception can be identified. It is generally preferable to use qualifying language such as "in my experience," "based on my review of the relevant literature," "to my knowledge," or "in the context of this analysis." The exception is where a technical principle is genuinely absolute — for example, a fundamental law of physics — in which case an unqualified statement is appropriate.
If shown a document, read it carefully before answering questions about it. Opposing counsel will likely present Dr. Ashford with numerous documents during the deposition — patent claims, prosecution history excerpts, prior-art references, teardown report pages, deposition transcript excerpts, and the like. When a document is placed before her, Dr. Ashford should take the time to read the relevant portions carefully before answering any questions about it. She should not rely on opposing counsel's characterization of what a document says; she should read it herself. If the document is lengthy, she may ask to be directed to the specific portion the questioner is asking about, and she should still read that portion in full before answering.
Do not characterize communications with C&H counsel or the substance of privileged discussions. Opposing counsel may ask questions designed to probe the nature, substance, or extent of Dr. Ashford's communications with C&H. These communications are protected by the attorney-client privilege and the work product doctrine. Dr. Ashford should not describe what counsel told her, what instructions she received, what legal conclusions were shared with her, or the substance of any conversations with C&H attorneys about litigation strategy. If such a question is asked, C&H counsel will assert the privilege on the record, and Dr. Ashford should refrain from answering. The one area where some disclosure is required relates to the facts and data Dr. Ashford considered in forming her opinions, which are discoverable under Federal Rule of Civil Procedure 26(b)(4)(C)(ii). However, even in this area, the distinction between "facts or data considered" and "privileged communications with counsel" should be carefully maintained, and C&H counsel will guide any necessary assertions of privilege during the deposition.
C. Demeanor
Dr. Ashford should project calm authority throughout the deposition. Her credentials — Professor of Electrical Engineering & Photonics at the Northfield Institute of Technology, with a distinguished record of research and publication in silicon photonics — speak for themselves. She does not need to be assertive or defensive in order to be credible; indeed, the most effective expert witnesses are those who are direct, confident, and fair-minded.
Dr. Ashford should avoid appearing combative or evasive. An expert who quarrels with opposing counsel or who evades straightforward questions damages her own credibility. Judges and juries reviewing deposition transcripts — or watching deposition video clips at trial — are perceptive about witness credibility, and they respond favorably to witnesses who answer questions honestly and without evasion, even when the questions are difficult.
An important corollary of this principle: if a question calls for a concession that is technically accurate, Dr. Ashford should make it cleanly and without equivocation. Credibility is the expert's most valuable asset, and an expert who refuses to acknowledge obvious truths — or who quibbles over immaterial points — undermines her credibility on the points that actually matter. For example, if opposing counsel asks whether a particular prior-art reference discloses certain elements of a claimed invention, and it plainly does, Dr. Ashford should acknowledge the disclosure and then, if appropriate, explain why other elements are missing or why the reference is distinguishable on other grounds. The concession on the easy point actually enhances Dr. Ashford's credibility when she contests the harder points.
Finally, Dr. Ashford should be aware of her physical presentation. She should maintain good posture, make appropriate eye contact with the questioner (or with the camera, if the deposition is conducted by videoconference), and speak clearly and at a moderate pace. She should avoid mannerisms that may convey nervousness or uncertainty, such as touching her face, fidgeting with papers, or looking away from the questioner when answering. She should feel free to ask for breaks as needed — the Federal Rules permit reasonable breaks during a deposition — and should not hesitate to request a break if she feels fatigued or if she needs to use the restroom. However, she should avoid requesting breaks at moments that could appear strategic (e.g., immediately after a difficult question has been asked but before she has answered).
III. ANTICIPATED LINES OF CROSS-EXAMINATION
The following sections address, topic by topic, the lines of cross-examination we anticipate HVC will pursue during Dr. Ashford's deposition. For each topic, we identify the likely questions, the key documents that may be used, and recommended approaches and pitfalls to avoid. This analysis is based on our review of HVC's litigation strategy to date, the issues raised in the pleadings and discovery, the claim construction proceedings, and our general experience with HVC counsel in other patent cases.
A. Qualifications and Bias
1. Expert Credentials and Background
Opposing counsel will begin, as is customary, by exploring Dr. Ashford's qualifications. While this portion of the deposition may appear routine, it serves several strategic purposes for HVC: (1) establishing the boundaries of Dr. Ashford's expertise for possible Daubert challenge purposes; (2) identifying areas where Dr. Ashford's academic background may be contrasted with real-world industry experience; and (3) setting a cooperative tone for later, more adversarial questioning.
We expect HVC to probe the scope of Dr. Ashford's academic and industry experience in silicon photonics, with particular emphasis on whether she has hands-on design experience with commercial transceiver modules — as opposed to academic research conducted in a university laboratory setting. The distinction between academic research and commercial product development is one that HVC will likely seek to exploit throughout the deposition, and Dr. Ashford should be prepared to explain how her academic research experience, combined with her consulting engagements and her review of the technical literature, gives her a comprehensive understanding of the technology at issue, including its commercial implementation.
Specifically, we expect questions about Dr. Ashford's publication record, including her body of peer-reviewed articles and conference papers. HVC may focus on particular sub-topics — for instance, whether Dr. Ashford has published on waveguide multiplexers specifically, whether she has published on thermal management of photonic integrated circuits, and whether she has published on polarization-diverse grating couplers. Each of these sub-topics corresponds to one or more of the patents-in-suit, and HVC may attempt to argue that Dr. Ashford's expertise is stronger in some areas than in others. Dr. Ashford should be prepared to discuss her publication record honestly and to explain how her broader expertise in silicon photonics provides a sufficient foundation for her opinions even in sub-areas where her publication record may be thinner.
HVC may also attempt to contrast Dr. Ashford's academic background with the industry-specific expertise of their own expert, Dr. Rajesh Sundaram, who holds the position of Professor of Electrical & Computer Engineering at Pacific Western University in San Diego, California. If HVC raises this comparison, Dr. Ashford should avoid being drawn into a direct comparison of credentials. She should simply confirm her own qualifications and express her opinions based on her own independent analysis, without commenting on Dr. Sundaram's qualifications or the merits of his opinions. Any direct engagement with Dr. Sundaram's qualifications risks appearing defensive or, worse, providing testimony that HVC could use to frame a favorable comparison for their own expert.
2. Compensation and Engagement History
HVC will inevitably explore Dr. Ashford's financial arrangement with C&H and with OWS. This line of questioning is designed to suggest that Dr. Ashford's opinions may be influenced by the compensation she receives for her work. While this is a standard line of attack against expert witnesses and is unlikely to carry significant weight with the Court or a jury on its own, it can be effective if the expert appears defensive or evasive about the financial details.
Dr. Ashford's retention agreement with C&H, dated August 1, 2024, provides for an hourly rate of $950 per hour, with an estimated total budget for Dr. Ashford's engagement of approximately $1.1 million. HVC will likely ask Dr. Ashford to confirm her hourly rate, the total number of hours she has billed to date, and the total amount of fees she has received. Dr. Ashford should be prepared to provide these figures accurately. If she does not have the precise figures at the time of the deposition, she should say so and provide her best estimate, making clear that it is an estimate.
HVC will also explore Dr. Ashford's prior expert engagements — both for C&H and for OWS, and for other law firms and parties in other cases. Dr. Ashford should be prepared to confirm or deny prior engagements and to state what percentage of her professional income is derived from expert witness work as opposed to her academic salary, research grants, and other sources. If a substantial portion of her income derives from expert witness work, HVC will argue this creates a financial incentive to provide favorable opinions. Dr. Ashford should respond to this line of questioning straightforwardly and without defensiveness.
The recommended response to any question designed to suggest financial bias is as follows: Dr. Ashford's opinions are based on her independent technical analysis of the patents, the accused products, the prior art, and the relevant technical literature. Her opinions would be the same regardless of who retained her or which side of the case she was asked to evaluate. Her compensation is based on the time she expends on her analysis, not on the outcome of the case. She has not been promised any bonus or additional compensation contingent on the outcome, and her retention agreement contains no such provision.
3. Relationship with Optiwave or Counsel
HVC will ask whether Dr. Ashford has any prior consulting, research, or advisory relationship with OWS or any of its employees, including Dr. Jian-Wei Huang (OWS's Chief Technology Officer) and Dr. Nikolai Petrov (Vice President of Engineering, Photonics Division). HVC will also ask whether Dr. Ashford has any prior relationship with Cascade IP Advisors, LLC, the patent prosecution firm that prosecuted the patents-in-suit, or with Dr. Martin Chu, a principal at that firm.
Dr. Ashford should answer these questions truthfully and completely. If there are any prior relationships — even casual or tangential ones, such as co-attendance at a conference, mutual acquaintance through a professional organization, or a brief consulting engagement years ago — Dr. Ashford should disclose them. An undisclosed relationship that is later discovered will be far more damaging to credibility than a relationship that is disclosed and explained.
HVC will also ask whether Dr. Ashford reviewed any privileged communications between OWS and its counsel, or received any legal conclusions or legal instructions from C&H. Dr. Ashford should confirm that she did not receive legal conclusions from counsel and that her opinions are her own. To the extent she received facts, data, or technical materials from counsel, that is standard practice for expert witness engagements and is entirely proper. If the questioning ventures into the substance of privileged communications, C&H counsel will assert the privilege.
B. Person of Ordinary Skill in the Art (POSITA) Definition
1. Dr. Ashford's POSITA Definition
The definition of a person of ordinary skill in the art is foundational to both the infringement analysis and the validity analysis. Dr. Ashford has defined a POSITA consistently across her Opening Claim Construction Declaration (submitted November 15, 2024) and both of her expert reports (served June 15, 2025). Her definition provides that a POSITA in this field would be a person holding a Master of Science (M.S.) or Doctor of Philosophy (Ph.D.) degree in electrical engineering or photonics, with at least three years of experience in silicon-photonic integrated circuit design.
We expect HVC to challenge this definition from multiple angles, depending on which claim construction or validity issue is at stake. In some contexts, HVC may argue that the POSITA definition is too narrow — for example, that it excludes individuals with equivalent practical experience but without formal graduate degrees, or that it excludes individuals with degrees in related fields such as materials science or applied physics. In other contexts, HVC may argue that the POSITA definition is too broad — for example, that it should require specialized experience in coherent optical communication systems (relevant to the '193 Patent) or in thermal management of integrated circuits (relevant to the '562 Patent).
Dr. Ashford should be prepared to defend her POSITA definition on its merits. The definition is grounded in the level of sophistication reflected in the patent specifications themselves — the patents use technical terminology and describe fabrication processes and design choices that would be understood by a person with the defined educational background and experience level. The definition is also consistent with the level of skill reflected in the prior art cited during prosecution, which includes academic journal articles, conference papers, and patents authored by individuals with comparable credentials. If pressed, Dr. Ashford can point to specific passages in the patent specifications and in the prior art that illustrate the level of technical knowledge assumed by the relevant literature.
Dr. Sundaram, Lumicore's expert, may have proposed a different POSITA definition — likely one requiring more industry-specific design experience, a different number of years of experience, or different educational qualifications. If Dr. Ashford is aware of Dr. Sundaram's definition (e.g., from his declaration submitted during claim construction on December 6, 2024), she should be prepared to explain why her definition is more appropriate and consistent with the state of the art at the time of each patent's filing. However, she should avoid directly criticizing Dr. Sundaram's definition in a manner that appears personal or adversarial; a calm, technical explanation of why her own definition is well-founded is more effective than a point-by-point attack on the competing definition.
2. Impact of POSITA Definition on Claim Construction and Validity
HVC will probe whether changing the POSITA definition would alter Dr. Ashford's opinions on the ordinary and customary meaning of the disputed claim terms. This line of questioning is designed to show that Dr. Ashford's infringement and validity opinions are sensitive to the POSITA definition and could change under a different definition — thereby suggesting that the opinions are fragile or result-oriented.
There are currently 14 disputed claim terms in this case, 12 of which remain in dispute following the agreement of the parties on two terms during the claim construction briefing. The 12 remaining disputed terms include, among others, "waveguide multiplexer" (from the '847 Patent), "integrated on a silicon substrate" (from the '193 Patent), "micro-channel heat sink" (from the '562 Patent), and "polarization-diverse grating coupler" (from the '015 Patent). For each of these terms, Dr. Ashford should be prepared to explain how her POSITA definition informs her understanding of the term's ordinary and customary meaning.
Of particular focus will be the term "integrated on a silicon substrate" from the '193 Patent. HVC will likely argue that a POSITA with more industry experience — for example, five or more years of experience in commercial transceiver design — would understand this term to require monolithic fabrication on a single silicon die, consistent with Lumicore's proposed claim construction. Under Lumicore's construction, the term excludes devices fabricated using hybrid bonding or heterogeneous integration techniques. OWS's broader construction — "formed on or within a silicon-based wafer using semiconductor fabrication processes" — encompasses both monolithic fabrication and hybrid integration approaches. Dr. Ashford should be prepared to explain why a POSITA with the credentials she has defined would understand the term in the broader sense, drawing on the patent specification's description of the fabrication process and the state of the art at the time of filing.
3. POSITA Knowledge and State of the Art
HVC will ask Dr. Ashford to describe what a POSITA would have known at the time of each patent's effective filing date. This line of questioning is relevant both to claim construction (the ordinary and customary meaning of claim terms is assessed from the perspective of a POSITA at the time of filing) and to validity (the obviousness inquiry is based on the state of the art at the time of filing). The relevant filing dates are as follows:
Dr. Ashford should be prepared to discuss the evolution of silicon-photonics technology during the period from 2014 through 2019 and to explain how a POSITA's understanding of key terms and technologies may or may not have changed over that period. For example, the use of hybrid bonding and heterogeneous integration techniques became more common in the later part of this period, which is relevant to the construction of "integrated on a silicon substrate." Similarly, the understanding of thermal management challenges in photonic integrated circuits evolved as power densities increased with higher data rates. Dr. Ashford should be able to place each patent in its technological context and explain what would have been known, what would have been novel, and what would have been non-obvious to a POSITA at each relevant date.
C. Infringement Opinions — Literal Infringement
1. '847 Patent (U.S. 10,234,847) — "Multi-Channel Silicon Photonic Waveguide Multiplexer with Low Insertion Loss"
The '847 Patent is directed to a multi-channel silicon photonic waveguide multiplexer designed to achieve low insertion loss, a critical performance parameter for optical communication systems. The asserted claims are Claims 1, 3, 5, 9, and 14. The accused products are the LumiLink 400G-ZR+ and the LumiLink 800G-DR8.
The key disputed claim term for this patent is "waveguide multiplexer." OWS proposes that this term should be construed to mean "an optical device that combines multiple optical signals of different wavelengths onto a single waveguide." Lumicore proposes a substantially narrower construction: "an arrayed waveguide grating that combines optical signals using a slab coupler and phase-shifted waveguide array." The difference between these constructions is significant. Under OWS's broader construction, any multiplexing architecture — including arrayed waveguide gratings (AWGs), Mach-Zehnder interferometer (MZI)-based designs, ring-resonator-based designs, and other architectures — would fall within the claim scope. Under Lumicore's narrower construction, only AWG-based multiplexers would infringe.
HVC will conduct a detailed element-by-element examination of each asserted claim, focusing on whether Lumicore's accused products use an AWG architecture (which would satisfy both parties' constructions) or a different multiplexing architecture (e.g., an MZI-based or ring-resonator-based design) that would satisfy only OWS's broader construction. Dr. Ashford should be intimately familiar with the architecture of the accused products as revealed by the Benchmark teardown reports and Lumicore's own design files, and she should be prepared to identify the specific structures in the accused products that correspond to each claim limitation.
Dr. Ashford should be prepared to walk through the Benchmark Semiconductor Analysis, LLC teardown report for the LumiLink 400G-ZR+ (delivered December 12, 2022, by Kevin Ng, Lead Engineer) and the follow-on teardown report for the LumiLink 800G-DR8 (completed June 2023). For each accused product, she should be able to identify the specific physical structures observed in the teardown — including waveguide geometries, coupler architectures, grating structures, and metallization layers — and explain how those structures correspond to each element of each asserted claim. She should be comfortable referring to specific figures, photographs, and SEM images from the teardown reports to support her testimony.
With respect to Claim 9, C&H's internal analysis (dated October 5, 2024) identified a potentially means-plus-function limitation in this claim. Under 35 U.S.C. § 112(f), a means-plus-function limitation is construed to cover the corresponding structure, material, or act described in the patent specification, and equivalents thereof. Dr. Ashford should be prepared to identify the corresponding structure in the '847 Patent specification that performs the claimed function and to explain how the structure in the accused product either is that structure or is an equivalent of that structure. This analysis is set forth in her Infringement Report, and she should be prepared to walk through it step by step.
HVC may also raise claim differentiation arguments with respect to the relationship between independent Claim 1 and dependent Claims 3 and 5. Specifically, HVC may argue that because dependent Claims 3 and 5 add limitations to Claim 1 that relate to specific structural features of the multiplexer, independent Claim 1 should be construed narrowly to exclude those features — otherwise, the argument goes, the dependent claims would be superfluous. Dr. Ashford should be prepared to explain why the claim-differentiation doctrine actually supports a broader construction of Claim 1. The doctrine creates a presumption that dependent claims add meaningful limitations to the independent claim, but it does not require that the independent claim be construed so narrowly as to exclude the subject matter of the dependent claims. Rather, the dependent claims narrow the scope of the independent claim by adding additional requirements; the independent claim, by definition, does not include those additional requirements and is therefore broader.
2. '193 Patent (U.S. 10,891,193) — "High-Bandwidth Coherent Optical Transceiver Integrated on Silicon Substrate"
The '193 Patent is directed to a high-bandwidth coherent optical transceiver integrated on a silicon substrate. It is the broadest of the four asserted patents in terms of the number of asserted claims (Claims 1, 3, 7, 10, 15, and 18) and accused products (all three Lumicore products — the LumiLink 400G-ZR+, the LumiLink 800G-DR8, and the LumiEdge 1600G-LR).
The key disputed terms for this patent are "integrated on a silicon substrate" and the "coherent detection module" limitation. These terms are central to both the literal-infringement analysis and the doctrine-of-equivalents analysis, and they will receive substantial attention during the deposition.
With respect to "integrated on a silicon substrate," OWS proposes the construction "formed on or within a silicon-based wafer using semiconductor fabrication processes," while Lumicore proposes "monolithically fabricated on a single silicon die without hybrid bonding or heterogeneous integration." The practical significance of this dispute is substantial: if the Court adopts Lumicore's narrow construction, the infringement analysis depends on whether the accused products are monolithically fabricated or instead use hybrid bonding or heterogeneous integration techniques to combine multiple semiconductor dies or materials on a single substrate.
Dr. Ashford must be prepared to testify about the fabrication methodology of each accused product. If the evidence indicates that one or more accused products use hybrid bonding — and there are indications from the Benchmark teardown data and from Lumicore's design files that certain accused products may incorporate hybrid-bonded III-V semiconductor laser sources on a silicon photonic platform — then the literal-infringement analysis under Lumicore's narrow construction would fail for those products. In that event, the infringement theory would depend on the doctrine of equivalents analysis set forth in Appendix B of Dr. Ashford's Infringement Report. Dr. Ashford should be prepared to explain how the DOE analysis addresses this gap, using the function-way-result framework discussed in Section III.D below.
With respect to Claim 15, C&H's internal analysis (October 5, 2024) identified a potentially means-plus-function limitation. As with Claim 9 of the '847 Patent, Dr. Ashford should be prepared to identify the corresponding structure in the '193 Patent specification and to explain how the accused products satisfy this limitation.
Importantly, the Markman hearing in this case occurred on March 14, 2025, before Judge James R. Gilstrap. Dr. Ashford's expert reports were drafted in light of the Court's claim construction ruling, and her opinions should be fully consistent with the Court's adopted constructions. HVC will scrutinize the reports for any inconsistency with the Markman order. Dr. Ashford should be prepared to confirm that her opinions are consistent with the Court's rulings and, if necessary, to explain how any aspect of her analysis was adjusted between her pre-Markman claim construction declaration (November 15, 2024) and her post-Markman expert report (June 15, 2025) to conform to the Court's constructions.
3. '562 Patent (U.S. 9,678,562) — "Method for Thermal Management of Photonic Integrated Circuits Using Embedded Micro-Channel Heat Sinks"
The '562 Patent is directed to a method for thermal management of photonic integrated circuits using embedded micro-channel heat sinks. The asserted claims are Claims 1, 4, 6, and 11, and the accused products are the LumiLink 400G-ZR+ and the LumiLink 800G-DR8.
The key disputed claim term for this patent is "micro-channel heat sink." OWS proposes the construction "a heat-dissipating structure containing channels with a hydraulic diameter of less than 1 mm." Lumicore proposes a substantially narrower construction: "a closed-loop liquid-cooling system with channels having a hydraulic diameter between 10 µm and 200 µm." The difference between these constructions is twofold: (1) OWS's construction does not require a closed-loop liquid-cooling system (it would encompass passive heat-dissipating structures as well as active liquid-cooling systems), whereas Lumicore's construction requires a closed-loop liquid-cooling system; and (2) the dimensional ranges differ — OWS's construction requires only that the hydraulic diameter be less than 1 mm, while Lumicore's construction requires the hydraulic diameter to be between 10 µm and 200 µm.
C&H has identified this patent as having the strongest literal-infringement case among the four asserted patents. The Benchmark teardown data clearly identified micro-channel structures in the accused products, and the measured channel dimensions fall squarely within the range claimed by both parties' proposed constructions. Accordingly, this is the patent for which the infringement analysis is most straightforward, and we anticipate that HVC's cross-examination will be more focused on validity and claim construction than on the element-by-element infringement mapping.
Nevertheless, Dr. Ashford should be prepared to explain in detail the teardown methodology used by Kevin Ng of Benchmark Semiconductor Analysis, LLC. She should be able to describe the general process of obtaining and preserving the accused product samples (chain of custody), the cross-sectioning technique used to expose the internal structures of the photonic integrated circuit, the scanning electron microscopy (SEM) imaging used to photograph the micro-channel structures, and the dimensional measurements taken from the SEM images. She should be prepared to explain how the measured channel dimensions of the accused products fall within the claimed range under any reasonable construction of "micro-channel heat sink."
An additional area of anticipated questioning relates to the provenance of the '562 Patent. This patent was originally assigned to Solara Optics, Inc. and was subsequently acquired by OWS pursuant to an Asset Purchase Agreement ("APA") dated June 15, 2018, for a total consideration of $34.5 million covering a portfolio of 12 patents (including the '562 Patent). HVC may probe Dr. Ashford's knowledge of the patent's provenance, any differences between the patent application as originally filed by Solara and the claims as ultimately issued, and whether any changes to the claims during prosecution affect the scope of the asserted claims or the infringement analysis. Dr. Ashford should be prepared to confirm that she is aware the patent was acquired from Solara but that her infringement analysis is based on the patent as issued, regardless of its ownership history. She should defer to counsel on any questions relating to the terms of the APA or the business rationale for the acquisition.
4. '015 Patent (U.S. 11,402,015) — "Polarization-Diverse Grating Coupler for Silicon Photonic Transceivers"
The '015 Patent is directed to a polarization-diverse grating coupler for silicon photonic transceivers. The asserted claims are Claims 1, 5, 8, 12, and 16, and the accused products are the LumiLink 800G-DR8 and the LumiEdge 1600G-LR.
The key disputed claim term for this patent is "polarization-diverse grating coupler." OWS proposes the construction "a grating coupler capable of coupling light of two orthogonal polarization states." Lumicore proposes the narrower construction "a two-dimensional grating coupler with a polarization-splitting element that simultaneously couples TE and TM modes." The difference is significant: OWS's broader construction would encompass grating couplers that handle orthogonal polarization states sequentially or in separate channels, as well as those that handle them simultaneously, whereas Lumicore's construction requires simultaneous coupling of both TE (transverse electric) and TM (transverse magnetic) modes through a two-dimensional grating with a dedicated polarization-splitting element.
An additional key limitation relevant to this patent is the "two-dimensional sub-wavelength grating" element recited in Claim 12. This limitation is the subject of a doctrine-of-equivalents analysis in Dr. Ashford's Infringement Report (Appendix B), as discussed in Section III.D below. The construction and scope of this limitation are particularly important because a narrowing amendment was made to this limitation during prosecution.
The '015 Patent shares a common provisional application — Provisional Application No. 62/499,117, filed April 7, 2017 — with the '193 Patent. This means that the two patents share the same priority date for claims that are supported by the provisional application, and the prosecution histories of the two patents are interrelated. Dr. Ashford should be prepared to discuss this relationship and to explain how the two patents cover different aspects of the same underlying technology — the '193 Patent covering the broader transceiver architecture and the '015 Patent covering the specific grating coupler design used in the transceiver's input/output interface.
Dr. Ashford should be prepared to explain how the accused products' grating coupler designs satisfy the claim limitations of the '015 Patent, with reference to Benchmark's February 2024 teardown of the LumiEdge 1600G-LR. The LumiEdge 1600G-LR teardown is the most recent of the three teardown reports and contains detailed SEM imagery of the grating coupler structures, including cross-sectional views showing the grating periodicity, fill factor, and etch depth, as well as top-down views showing the two-dimensional pattern of the grating. Dr. Ashford should be comfortable identifying these features in the teardown images and explaining their correspondence to the claimed limitations.
D. Doctrine of Equivalents (DOE) — Critical Area
1. Scope of DOE Contentions
The doctrine of equivalents is a judicially created doctrine that extends patent protection beyond the literal scope of the claims to encompass equivalents that perform substantially the same function, in substantially the same way, to achieve substantially the same result as the claimed limitation. OWS's infringement contentions include DOE claims for the following specific limitations:
• Claims 3 and 7 of the '193 Patent: Specifically, the "coherent detection module" limitation. Dr. Ashford's infringement analysis concluded that the accused products may not literally satisfy this limitation under certain claim constructions, but that the accused products' coherent receiver architecture performs substantially the same function, in substantially the same way, to achieve substantially the same result as the claimed "coherent detection module."
• Claim 12 of the '015 Patent: Specifically, the "two-dimensional sub-wavelength grating" limitation. Dr. Ashford's analysis concluded that the accused products' grating structures, while differing in certain respects from the literal claim language (as narrowed during prosecution), are equivalent to the claimed limitation under the function-way-result test.
Dr. Ashford's Infringement Report includes Appendix B, which sets forth a detailed function-way-result analysis for each of these DOE contentions. This appendix identifies the specific differences between the claim elements and the corresponding elements in the accused products, and explains why those differences are insubstantial under the equivalents test. Dr. Ashford should review Appendix B thoroughly before the deposition and should be prepared to articulate the analysis from memory, without needing to refer to the written report.
2. Function-Way-Result Analysis
For each DOE contention, HVC will probe each prong of the function-way-result test in detail. We anticipate that HVC will structure this examination as follows:
Function: HVC will ask Dr. Ashford to identify the function performed by the claim element (e.g., the "coherent detection module" limitation) and the function performed by the corresponding element in the accused product. HVC will then ask whether these functions are substantially the same. Dr. Ashford should be prepared to articulate the function clearly and specifically — not at an overly high level of abstraction (which could vitiate the limitation) and not at an overly granular level (which could create artificial distinctions between the claim element and the accused element).
Way: HVC will ask Dr. Ashford to describe the manner in which the claim element performs its function and the manner in which the accused element performs its function. This is often the most contested prong of the analysis, because it requires a detailed comparison of the technical mechanisms employed by the claim element and the accused element. HVC will attempt to elicit testimony that the accused element operates in a fundamentally different way from the claim element, which would defeat the DOE theory. Dr. Ashford should be prepared to explain, with technical specificity, why the "way" employed by the accused element is substantially the same as the "way" employed by the claim element, even if there are superficial differences in implementation.
Result: HVC will ask Dr. Ashford to identify the result achieved by the claim element and the result achieved by the accused element, and whether these results are substantially the same. This prong is often the most straightforward, but Dr. Ashford should not treat it as a mere formality — she should articulate the result clearly and explain why the accused element achieves substantially the same result.
Throughout this examination, HVC will attempt to elicit admissions that the accused elements differ from the claim elements in some material respect. Dr. Ashford should not resist acknowledging differences where they exist — the entire premise of the DOE analysis is that there are differences between the claim language and the accused product. The question is not whether differences exist (they do, by definition, or the analysis would be one of literal infringement), but whether those differences are insubstantial. Dr. Ashford should acknowledge the differences candidly and then explain, with technical specificity, why those differences are insubstantial under the equivalents test.
3. Prosecution History Estoppel (Festo)
This is expected to be a major focus of cross-examination, and it represents one of the most significant areas of vulnerability in OWS's infringement case.
Under Festo Corp. v. Fenmore & Co., 535 U.S. 722 (2002), when a patent applicant narrows a claim during prosecution to secure the patent, there is a presumption that the applicant surrendered the territory between the original claim and the amended claim. This "Festo presumption" bars the application of the doctrine of equivalents to recapture the surrendered territory, unless one of three exceptions applies: (1) the equivalent at issue was unforeseeable at the time of the amendment; (2) the rationale underlying the amendment bears no more than a tangential relation to the equivalent at issue; or (3) there is some other reason suggesting that the patentee could not reasonably have been expected to have drafted a claim that literally encompassed the equivalent.
Both DOE contentions in this case are subject to Festo analysis because the relevant claim limitations were narrowed during prosecution:
'193 Patent — Claims 3 and 7 ("coherent detection module"): During prosecution of the '193 Patent, the "coherent detection module" limitation was narrowed in response to a rejection under 35 U.S.C. § 102 (anticipation) based on the Takahashi et al. reference ("Dense WDM Silicon Photonic MUX," IEEE Photonics Technology Letters, March 2014). The original claim language described the coherent detection module in broader terms, and the applicant amended the claim to add specific structural or functional requirements to distinguish Takahashi. C&H's internal Prosecution History Estoppel Analysis, dated October 10, 2024, assessed the impact of this amendment on the DOE theory.
Dr. Ashford must be prepared to explain the following three elements of this analysis:
(a) The nature of the amendment: What was the original claim language? What was the amended claim language? What was added, removed, or modified?
(b) Why the amendment was made: The amendment was made in response to the examiner's specific rejection based on Takahashi. The examiner found that Takahashi disclosed the original claim language, and the applicant narrowed the claim to distinguish Takahashi's specific disclosure. The amendment was directed at a particular feature of Takahashi — not at the general concept of coherent detection.
(c) Whether the Festo exception applies: Specifically, whether the equivalent at issue in the accused products is tangential to the reason the amendment was made. The argument is that the narrowing amendment was made to distinguish a specific feature of Takahashi that is different from the feature present in Lumicore's accused products. The equivalent found in Lumicore's products relates to a different aspect of the coherent detection module — one that was not the basis for the examiner's rejection and was not the reason for the narrowing amendment.
Key pitfall: If Dr. Ashford characterizes the amendment as directly related to the specific equivalent at issue in the accused products, it could undermine the entire DOE theory for Claims 3 and 7 of the '193 Patent. She should be prepared to explain, with reference to the prosecution history, why the narrowing amendment was directed at distinguishing a specific feature of Takahashi that is different from the feature present in Lumicore's accused products. This requires a precise understanding of both the Takahashi reference and the accused products' coherent detection architecture.
'015 Patent — Claim 12 ("two-dimensional sub-wavelength grating"): During prosecution of the '015 Patent, a narrowing amendment was made to the "two-dimensional sub-wavelength grating" limitation in order to overcome a rejection under 35 U.S.C. § 103 (obviousness) based on a combination of the Bergmann patent (U.S. 8,412,007, issued April 2, 2013) and the Simonsen PCT application (PCT/EP2015/071234, filed September 17, 2015). C&H's internal Prosecution History Estoppel Analysis, dated October 12, 2024, evaluated this amendment.
The Festo analysis for this claim follows a similar structure. Dr. Ashford should be prepared to explain the nature of the amendment, the reason it was made (to overcome the examiner's § 103 rejection based on the specific combination of Bergmann and Simonsen), and why one of the Festo exceptions applies. In this case, either the tangential-relation exception or the unforeseeability exception may apply. The tangential-relation exception would apply if the reason for the amendment (distinguishing the Bergmann/Simonsen combination) bears no more than a tangential relation to the equivalent found in Lumicore's accused products. The unforeseeability exception would apply if the particular equivalent used by Lumicore was not foreseeable at the time of the amendment — for example, if the technology used by Lumicore was not commercially available or known in the art at the time of prosecution.
HVC will likely walk through the prosecution history in meticulous detail, showing Dr. Ashford the original claim language, the examiner's rejection, and the amended claim language side by side. HVC will then ask Dr. Ashford to identify precisely what territory was surrendered by the amendment and to explain how the equivalent in the accused product falls outside the surrendered territory. This is a technically demanding line of questioning, and Dr. Ashford should prepare for it extensively during the practice sessions described in Section VII below.
4. Vitiation / All-Limitations Rule
In addition to prosecution history estoppel, HVC may argue that applying the doctrine of equivalents to certain claim limitations would effectively "vitiate" those limitations — that is, it would render the limitation meaningless by allowing it to be satisfied by any structure, regardless of how different it is from the claimed element. This argument is related to the "all-limitations rule," which requires that each element of a claim be present in the accused product, either literally or equivalently. Under this rule, the doctrine of equivalents cannot be applied in a manner that effectively reads a claim limitation out of the claim.
Dr. Ashford should be prepared to explain why her DOE analysis respects the all-limitations rule. For each DOE contention, the equivalent element in the accused product still corresponds to a specific, identifiable claim limitation — it is not broader than the claimed limitation, and it does not render the limitation superfluous. The accused element performs the same function, in the same way, to achieve the same result — it is merely a different specific implementation of the same technical concept. The existence of differences between the claim element and the accused element is what necessitates the DOE analysis in the first place; those differences do not vitiate the claim limitation unless they are so fundamental as to render the claim element meaningless.
E. Validity Opinions — Rebuttal of Invalidity Contentions
1. Overview. Lumicore's invalidity contentions, served on October 14, 2024, cite 23 prior-art references across all four asserted patents. These references include academic journal articles, conference papers, patents, patent applications, and internal Lumicore design documents. The invalidity contentions assert both anticipation under 35 U.S.C. § 102 and obviousness under 35 U.S.C. § 103 against various claims of each asserted patent.
Dr. Ashford's Validity Report, served on June 15, 2025, addresses each of the 23 references and opines that none anticipates or renders obvious any asserted claim of any of the four patents-in-suit. Her report includes Appendix A, which contains detailed claim charts for each of the 23 references, demonstrating the specific claim limitations that each reference fails to disclose and the specific features that distinguish the claimed inventions from the prior art.
HVC will cross-examine Dr. Ashford on her validity opinions with the goal of establishing that one or more of the prior-art references does in fact anticipate or render obvious the asserted claims. The examination will likely focus on the references that HVC considers its strongest invalidity arguments, which we have identified based on the invalidity contentions and the discovery to date. The key references are discussed below.
2. Key Prior-Art References — Anticipated Focus
a. Takahashi et al. — '847 Patent Anticipation (§ 102). The Takahashi reference is "Dense WDM Silicon Photonic MUX," published in IEEE Photonics Technology Letters in March 2014. HVC will argue that this reference discloses all elements of one or more of the asserted claims of the '847 Patent, rendering those claims anticipated under § 102.
Dr. Ashford should be prepared to walk through her claim chart for Takahashi (in Appendix A of her Validity Report) and to identify the specific claim limitations that Takahashi does not disclose. She should also be prepared to explain any features that Takahashi teaches away from — that is, any aspects of the reference that affirmatively discourage a POSITA from arriving at the claimed invention. For anticipation, the standard is strict: a single reference must disclose each and every element of the claim, arranged as in the claim. If even one element is missing, the anticipation argument fails. Dr. Ashford should identify the missing elements clearly and specifically.
We note that Takahashi is also relevant to the prosecution history estoppel analysis for the '193 Patent (see Section III.D.3 above), as it was the reference cited in the § 102 rejecti

MEMORANDUM

I. PURPOSE AND SCOPE OF THIS MEMORANDUM

II. GENERAL DEPOSITION GUIDANCE

III. ANTICIPATED LINES OF CROSS-EXAMINATION

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