PRIVILEGED AND CONFIDENTIAL ATTORNEY-CLIENT COMMUNICATION / ATTORNEY WORK PRODUCT
CALDERWOOD & HARKNESS LLP One Embarcadero Center, 34th Floor San Francisco, California 94111 Telephone: (415) 555-2400 Facsimile: (415) 555-2401
March 25, 2023
INTERNAL MEMORANDUM
Matter: Optiwave Semiconductor Corp. v. Lumos Photonics, Inc., Case No. 5:22-cv-03417-EJD (N.D. Cal.)
Matter Number: 1014-00003
To: Alan Ngo, Responsible Partner Omar Siddiqui, Lead Associate Christy Bauer, Working Associate
From: Marcus Delgado, Billing Partner, and Alan Ngo, Responsible Partner
Re: Cost-Benefit Analysis — Walk-Away Settlement vs. Continued Litigation Through Trial
CONFIDENTIALITY NOTICE: This memorandum is protected by the attorney-client privilege and the work product doctrine. It is prepared for the sole purpose of advising the client, Optiwave Semiconductor Corp. ("OWS"), and the attorneys working on this matter. This document contains the mental impressions, conclusions, opinions, and legal theories of the attorneys at Calderwood & Harkness LLP ("C&H"). It should not be disclosed to third parties without the express written consent of Calderwood & Harkness LLP and Optiwave Semiconductor Corp. Any inadvertent disclosure does not constitute a waiver of any applicable privilege or protection.
I. Executive Summary
This memorandum provides a comprehensive quantitative and qualitative comparison of the two resolution paths now available to Optiwave Semiconductor Corp. ("OWS") following Lumos Photonics, Inc.'s ("Lumos") March 22, 2023 walk-away counteroffer. The two paths are as follows:
(A) Accept the Walk-Away Settlement: Mutual general releases of all claims and counterclaims, zero payment in either direction, each side bears its own attorneys' fees and costs, no license granted under any patent of either party, no admission of infringement, validity, or invalidity by either party, and a joint stipulation of dismissal with prejudice to be filed with the Court.
(B) Reject the Walk-Away and Continue Litigation Through Trial: Proceed through remaining fact discovery, expert discovery, dispositive motions, and ultimately a jury trial before the Honorable Edward J. Torvelis in the Northern District of California, San Jose Division.
Bottom-Line Conclusion. We recommend that OWS accept the walk-away settlement. It is the economically rational outcome. Continuing litigation through trial would require an estimated additional $1.65 million in attorneys' fees, expert fees, and costs — against a post-Markman expected monetary recovery of near zero. When subjected to rigorous expected-value analysis, the net expected value of continued litigation is approximately negative $1.6 million. This figure accounts for the dramatically reduced probability of proving infringement on any asserted claim (estimated at less than five percent following the adverse Markman Order), the meaningful risk of adverse invalidity rulings on Lumos's counterclaims (estimated at 25–40%), the non-trivial risk of an exceptional-case finding and fee-shifting under 35 U.S.C. § 285 (estimated at 5–10%), and the substantial operational distraction costs to OWS during a critical product development cycle.
Context. The Markman Order entered by the Court on February 17, 2023, fundamentally altered the trajectory of this case. In its 34-page claim construction opinion, the Court adopted Defendant's proposed construction — or substantially Defendant-aligned constructions — on eight of eleven disputed claim terms across all four patents-in-suit. As detailed in C&H's internal post-Markman assessment memorandum dated February 21, 2023 (attached hereto as Appendix A), the Court's constructions render infringement theories untenable as to three of the four asserted patents (the '567 Patent, the '234 Patent, and the '678 Patent) and significantly weaken the infringement theory as to the fourth (the '890 Patent). Only marginal, highly speculative doctrine-of-equivalents arguments survive as to the '890 Patent, and those arguments face substantial prosecution history estoppel barriers.
Following the Markman Order, OWS's Board of Directors authorized settlement discussions during a meeting on February 24, 2023, at which C&H presented its Markman impact assessment (Appendix B). Discussions commenced on March 6, 2023, when the undersigned, Alan Ngo, contacted Victoria Ashworth of Brannick Howell & Stein LLP ("BHS"), counsel for Lumos. The parties agreed to a 30-day settlement window, and a stipulated stay of all discovery deadlines was entered on March 10, 2023. On March 15, 2023, OWS proposed a cross-license with a nominal $500,000 royalty payment from Lumos to OWS, covering OWS's full 87-patent portfolio and Lumos's patent portfolio. Lumos rejected this proposal outright on approximately March 20, 2023. On March 22, 2023, Lumos counteroffered the walk-away terms described above. This memorandum evaluates whether OWS should accept that counteroffer or continue litigating.
II. Background and Procedural Posture
A. Case Overview
Plaintiff. Optiwave Semiconductor Corp. ("OWS") is a Delaware corporation headquartered in San Jose, California. OWS is a fabless semiconductor company that designs and develops silicon photonics integrated circuits and optical interconnect solutions for data center and telecommunications applications. For fiscal year 2022, OWS reported total revenue of approximately $187.4 million, reflecting year-over-year growth of approximately 23% driven by the adoption of its OWS-400ZR coherent optical chipset by several hyperscale cloud customers. OWS is majority-owned, at approximately 62%, by Vantage Point Capital Partners Fund IV, LP ("Vantage Point"), a venture capital fund managed by Vantage Point Capital Partners LLC. The remaining equity is held by OWS management, employees, and earlier-round investors.
Defendant. Lumos Photonics, Inc. ("Lumos") is a Delaware corporation headquartered in Austin, Texas. Lumos is a publicly traded company listed on the Nasdaq Stock Market under the ticker symbol LMPH. Lumos designs, manufactures, and sells photonic integrated circuits and optical modules for high-speed data communications. For fiscal year 2022, Lumos reported total revenue of approximately $312.8 million, with a market capitalization of approximately $2.24 billion as of the date of this memorandum. Lumos maintains its own fabrication facilities in Austin, Texas and Penang, Malaysia.
Court. This action is pending in the United States District Court for the Northern District of California, San Jose Division, before the Honorable Edward J. Torvelis, under Case No. 5:22-cv-03417-EJD. OWS filed its complaint on June 14, 2022. Lumos answered and asserted counterclaims for declaratory judgments of non-infringement, invalidity, and unenforceability on August 5, 2022.
Patents-in-Suit. OWS asserts infringement of four United States patents:
Accused Products. OWS accuses two Lumos products of infringing the patents-in-suit:
(i) LumosBridge™ 800G Optical Engine — a silicon photonics-based optical engine designed for 800G Ethernet and data center interconnect ("DCI") applications, launched in Q1 2022; and
(ii) LumosEdge™ 400ZR+ Pluggable Transceiver — a QSFP-DD form factor pluggable coherent transceiver for 400G ZR+ applications, launched in Q3 2021.
The combined accused product revenue for calendar year 2022 was approximately $148.6 million, based on publicly available financial disclosures and Lumos's segment reporting. This figure served as the foundation for the royalty base in OWS's pre-Markman damages analysis.
B. The Markman Order (February 17, 2023)
On February 17, 2023, following a two-day Markman hearing held on January 30–31, 2023, the Court issued a 34-page claim construction order construing all eleven disputed claim terms across the four patents-in-suit. The order represents a decisive and overwhelmingly adverse outcome for OWS. The Court adopted Defendant's proposed construction, or substantially Defendant-aligned constructions, on eight of the eleven terms, adopted Plaintiff's construction on only two terms, and adopted a modified construction (which neither party had proposed) on one term. In practical effect, the constructions adopted by the Court exclude the accused Lumos products from the scope of the asserted claims on three of the four patents and severely narrow the scope of the fourth.
The key adverse constructions are summarized below:
'567 Patent — "adiabatically coupled." The Court construed the term "adiabatically coupled" to mean "coupled through a gradual, continuous taper designed and configured to prevent excitation of higher-order modes over the entire transition length." This construction is critical because Lumos's LumosBridge™ 800G Optical Engine employs a segmented, non-continuous taper design with discrete coupling sections — an architecture that falls squarely outside the Court's construction requiring a "gradual, continuous taper." OWS had argued for a broader construction — "coupled through a taper that transitions optical energy between waveguides with low loss" — that would have encompassed both continuous and segmented taper designs. The Court rejected OWS's construction, finding that the specification consistently described "adiabatic coupling" in terms of gradual, continuous transitions and that the prosecution history reflected the applicant's intent to claim only continuous-taper embodiments when distinguishing the Tanaka prior art reference (U.S. Patent No. 9,456,012).
'234 Patent — "graded buffer layer having a continuously varying germanium concentration." The Court construed this term to mean "a buffer layer in which the germanium atomic fraction increases monotonically and without step changes from the silicon substrate interface to the absorber layer." This construction is devastating to OWS's infringement case as to the '234 Patent because Lumos's accused photodetector structure employs a step-graded SiGe buffer with four discrete composition steps, in which the germanium atomic fraction increases in distinct increments of approximately 0.25, 0.50, 0.75, and 1.0. OWS had proposed a construction that would have encompassed buffers with either continuous or step-graded germanium concentration profiles, arguing that the specification disclosed both embodiments. The Court disagreed, finding that the claim language "continuously varying" was unambiguous and that the specification's discussion of step-graded embodiments appeared only in the context of alternative approaches that were distinguished from the claimed invention.
'678 Patent — "monolithically formed on a single silicon die." The Court construed this term to mean "fabricated entirely within the same front-end-of-line and back-end-of-line semiconductor processing sequence on a single silicon substrate without heterogeneous bonding or attachment of separately fabricated optical components." This construction excludes Lumos's manufacturing process for the LumosEdge™ 400ZR+ Pluggable Transceiver, which utilizes micro-transfer-printed III-V (indium phosphide) gain elements that are fabricated separately and then bonded to the silicon photonic integrated circuit ("PIC") substrate. The Court's emphasis on the exclusion of "heterogeneous bonding or attachment of separately fabricated optical components" directly targets the architecture employed by Lumos and a number of other silicon photonics manufacturers. OWS had argued for a broader construction that would have included hybrid integration techniques where the final device exists on a single silicon die regardless of the fabrication process used to place optical components thereon. The Court found that the prosecution history foreclosed this interpretation, noting that the applicant expressly distinguished "heterogeneous integration approaches" in remarks made during prosecution.
'890 Patent — "co-integrated." The Court construed "co-integrated" to require "fabrication in the same semiconductor process, sharing doping profiles and process layers, without bond wires, interposers, or package-level routing." This construction excludes Lumos's design for the LumosBridge™ 800G Optical Engine, which employs a separate CMOS driver die that is flip-chip bonded to the silicon photonic integrated circuit via copper pillar micro-bumps. Under the Court's construction, the use of separately fabricated CMOS and photonic dies connected by flip-chip bonding — even at the die level — falls outside the scope of "co-integrated" because the components do not share doping profiles and process layers and because the copper pillar micro-bumps constitute a form of package-level routing excluded by the construction. Of the four adverse constructions, this one leaves the most residual room for argument, as discussed in Section IV.B.1 below, but the infringement theory is nonetheless highly unlikely to succeed.
It should be noted that the two claim terms on which the Court adopted OWS's proposed construction — "optical waveguide" (plain and ordinary meaning) and "photodetector array" (plain and ordinary meaning) — are terms of minor significance that do not materially advance OWS's infringement theories in light of the adverse constructions on the dispositive terms discussed above.
C. Post-Markman Events
The sequence of events following the Markman Order has moved rapidly:
February 21, 2023 — C&H Post-Markman Assessment. C&H prepared and circulated an internal memorandum assessing the impact of the Markman Order on each of OWS's infringement theories. That memorandum (attached as Appendix A) concluded that the Court's claim constructions render infringement theories untenable as to three of the four patents-in-suit (the '567, '234, and '678 Patents) and significantly weaken the infringement theory as to the '890 Patent. The memorandum recommended that OWS promptly initiate settlement discussions to achieve the best available resolution before the discovery stay lapsed.
February 24, 2023 — OWS Board Meeting. C&H presented its Markman impact assessment to the OWS Board of Directors in a special meeting held by videoconference. Dr. Priya Ramanathan (CEO) and Sandra Ellison (General Counsel) participated along with all six Board members and Douglas Fairbanks III and Rebecca Torres representing Vantage Point Capital Partners. Following the presentation, the Board authorized settlement discussions and delegated negotiating authority to OWS's General Counsel, Sandra Ellison, in consultation with C&H.
March 6, 2023 — Settlement Discussions Initiated. Alan Ngo contacted Victoria Ashworth of Brannick Howell & Stein LLP, lead counsel for Lumos, to initiate settlement discussions. The parties agreed to a 30-day window for good-faith settlement negotiations, with the understanding that either party could terminate the discussions at any time.
March 10, 2023 — Stipulated discovery Stay. The parties filed a joint stipulation, and the Court entered an order, staying all discovery deadlines pending the conclusion of settlement discussions. The stay is effective through April 9, 2023, unless extended by further stipulation or order.
March 15, 2023 — OWS Cross-License Proposal. OWS proposed a settlement consisting of a cross-license covering OWS's full 87-patent portfolio and Lumos's patent portfolio, with a nominal $500,000 one-time royalty payment from Lumos to OWS, a mutual covenant not to sue on all current products, and a dismissal of the litigation with prejudice.
March 20, 2023 (approximately) — Lumos Rejects Cross-License. Lumos rejected OWS's cross-license proposal. Victoria Ashworth communicated that Lumos had no interest in a cross-license arrangement, viewed the Markman Order as vindicating Lumos's independent design position, and saw no commercial need for a license to OWS's patent portfolio.
March 22, 2023 — Lumos Walk-Away Counteroffer. Lumos counteroffered a walk-away settlement consisting of mutual general releases, zero payment in either direction, each side bearing its own attorneys' fees and costs, no license, no admissions, and a joint stipulation of dismissal with prejudice. The walk-away counteroffer was communicated by Victoria Ashworth via email to Alan Ngo and is attached as Appendix D.
D. Settlement Authority
C&H submitted a Settlement Authority Memorandum to the OWS Board in connection with the February 24, 2023 meeting. The Board authorized settlement discussions at that time but did not grant blanket authority to accept specific terms. Formal authority to accept the walk-away terms described in this memorandum must be obtained from the Board and from Vantage Point Capital Partners (specifically, Douglas Fairbanks III, Managing Partner, and Rebecca Torres, General Counsel, of Vantage Point Capital Partners LLC). C&H recommends that this authority be sought promptly, as discussed in Section IX below.
III. Option A: Accept the Walk-Away Settlement
A. Terms of Lumos's Walk-Away Proposal
Lumos's March 22, 2023 walk-away proposal, as communicated by Victoria Ashworth of BHS, consists of the following terms:
1. No Monetary Payment. Zero dollars ($0) to be paid by either party to the other. Each party walks away without making or receiving any payment.
2. Mutual General Releases. Both parties execute mutual general releases of all claims, counterclaims, cross-claims, and causes of action arising from or related to the litigation styled Optiwave Semiconductor Corp. v. Lumos Photonics, Inc., Case No. 5:22-cv-03417-EJD (N.D. Cal.). The releases would cover all claims that were asserted or could have been asserted in connection with the four patents-in-suit and the accused products identified in the litigation.
3. No License. No license is granted by either party to the other under any patent, trade secret, copyright, or other intellectual property right. OWS retains all rights in its patent portfolio. Lumos retains all rights in its patent portfolio.
4. Each Party Bears Its Own Costs. Each party bears its own attorneys' fees, expert fees, costs, and expenses incurred in connection with the litigation. No cost-shifting, fee-shifting, or reimbursement of any kind.
5. No Admissions. Neither party admits infringement, non-infringement, validity, invalidity, enforceability, or unenforceability of any patent. Neither party admits any fault, liability, or wrongdoing of any kind.
6. Dismissal with Prejudice. The parties agree to file a Joint Stipulation of Dismissal with Prejudice under Federal Rule of Civil Procedure 41(a)(1)(A)(ii), dismissing all claims and counterclaims with prejudice, with each party bearing its own costs.
7. Settlement Agreement and Mutual Release. The parties agree to execute a written Settlement Agreement and Mutual Release memorializing the foregoing terms. The agreement would include standard provisions regarding integration, governing law, counterparts, and confidentiality.
The proposed terms are straightforward and customary for walk-away settlements. There are no unusual provisions, restrictive covenants, or hidden obligations that would disadvantage OWS.
B. Financial Impact of Walk-Away
The financial impact of accepting the walk-away is, in practical terms, limited to the sunk costs already incurred. Those sunk costs are irrecoverable under either scenario (walk-away or continued litigation) and therefore do not factor into the marginal cost-benefit analysis. However, for completeness, we summarize the total litigation expenditure below.
Total Litigation Spend to Date (Sunk Costs):
These costs are sunk. They are irrecoverable regardless of whether OWS accepts the walk-away or continues litigating. The walk-away does not change the magnitude of the sunk costs, but it does stop the clock on future expenditures.
No Material Additional Costs Under Walk-Away. Under the walk-away, the only additional costs would be the minor drafting and negotiation expenses associated with finalizing the Settlement Agreement and Mutual Release and preparing the Joint Stipulation of Dismissal with Prejudice. We estimate these costs at less than $10,000 and note that they are within the scope of fees already budgeted for this matter under the current engagement letter.
Retainer Balance. OWS has made cumulative retainer deposits of $400,000, consisting of four quarterly replenishments of $100,000 each. Of this amount, $337,512 has been applied against fees and costs. The remaining retainer balance of approximately $62,488 will be returned to OWS upon matter close, in accordance with the terms of C&H's engagement letter.
C. Non-Financial Considerations of Walk-Away
Beyond the financial analysis, the walk-away offers several significant non-financial benefits to OWS:
Elimination of Management Distraction. The litigation has imposed a meaningful burden on OWS's management team and technical personnel. Dr. Priya Ramanathan (CEO), Dr. Kevin Fong (VP of Engineering), Sandra Ellison (General Counsel), and Ted Marchetti (VP of Business Development) have each invested significant time in providing litigation support, reviewing discovery materials, preparing for depositions, and attending status meetings with C&H. In addition, approximately a dozen members of OWS's engineering staff have been involved in responding to Lumos's 98 document requests and preparing technical explanations for infringement and claim construction positions. The walk-away immediately ends all of these obligations, freeing OWS's leadership and technical team to focus on the company's core business, including the critical OWS-800LR coherent chipset development and commercialization program that is currently in its pre-production qualification phase.
Preservation of Patent Portfolio. The walk-away preserves OWS's patent portfolio intact. The four asserted patents remain issued and enforceable. While the Markman constructions entered in this case are adverse, they are binding only in this litigation and are not binding on other courts in future proceedings. If OWS asserts these patents against other defendants in the future — for example, against competitors whose products employ continuous tapers, continuously graded buffers, true monolithic integration, or genuine co-integration — the claim construction analysis would begin anew, and a different court may adopt different constructions. Importantly, the walk-away avoids the risk that continued litigation in this case would produce published adverse rulings on validity or enforceability, which could be cited by future adverse parties in other proceedings and which could affect OWS's ability to monetize its broader 87-patent portfolio and 14 pending applications.
No Adverse Precedent. A dismissal with prejudice eliminates the case from the docket without any published ruling on the merits of infringement, validity, or enforceability. There will be no jury verdict, no summary judgment ruling, and no published opinion that could be cited against OWS in future proceedings. The Markman Order itself, of course, is already part of the public record and could theoretically be cited by future adverse parties as persuasive authority on claim construction, but its precedential value is limited because claim construction is a case-specific inquiry and because different accused products may raise different construction issues.
No Covenant Not to Sue. Critically, the walk-away terms do not include any covenant not to sue. OWS retains the full right to assert any of its patents — including the four asserted in this case — against Lumos's future products that may fall within the scope of OWS's claims under different or evolving claim constructions. OWS also retains the right to assert any of its other 83 patents and 14 pending applications against Lumos at any time for any products, subject only to the mutual release of claims arising from this specific litigation.
Elimination of Invalidity and Unenforceability Risk. Lumos has asserted counterclaims for invalidity under 35 U.S.C. §§ 102 (anticipation) and 103 (obviousness), and for unenforceability under 35 U.S.C. § 112 (written description and enablement). These counterclaims are supported by several prior art references and, as discussed in Section IV.B.2 below, carry a non-trivial probability of success (estimated at 25–40% for at least one invalidity finding). An adverse invalidity or unenforceability finding would be far more damaging to OWS than the walk-away because it could invalidate or render unenforceable one or more of OWS's patents not only as against Lumos but as against the world. The walk-away eliminates this risk entirely.
Elimination of Exceptional-Case Risk. Although the risk is modest, there is a non-trivial possibility (estimated at 5–10%) that if the case proceeds to trial and OWS fails to prove infringement, the Court could find this to be an "exceptional case" under 35 U.S.C. § 285 and award Lumos its attorneys' fees. An exceptional-case finding would be premised on the argument that OWS continued to prosecute claims that were objectively baseless in light of the Markman constructions. Lumos's attorneys' fees are estimated at $1.5 million to $2.5 million through trial. The walk-away eliminates this risk.
D. Effect on IP Portfolio Valuation
Prior to the commencement of this litigation, OWS engaged Clearpath IP Valuation Services to conduct a portfolio-level valuation of OWS's intellectual property assets. The valuation, prepared by Jennifer Armitage, CFA, CLP, and dated April 2022, assigned a portfolio-level value of approximately $215 million to OWS's total patent portfolio, with the four asserted patents collectively valued at approximately $42.8 million (representing approximately 19.9% of total portfolio value). The valuation summary is attached as Appendix E.
The Markman constructions materially impair the value of the four asserted patents insofar as they relate to Lumos's specific products and architectural choices. However, the patents retain meaningful value against competitors that employ different architectures falling within the scope of the claims as construed — for example, competitors using continuous tapers (as opposed to Lumos's segmented tapers), continuously graded SiGe buffers (as opposed to Lumos's step-graded buffers), true monolithic integration (as opposed to Lumos's micro-transfer-printing), and genuine co-integration (as opposed to Lumos's flip-chip bonding). The silicon photonics industry is diverse, and not all participants have adopted the same design choices as Lumos.
Critically, the walk-away avoids the risk of published invalidity findings that could diminish the value of the four patents — and potentially other patents in OWS's portfolio — far more broadly. An invalidity finding on any of the four patents would reduce its value to zero against all potential infringers, not merely against Lumos. Given that Lumos has identified substantial prior art and that the probability of an adverse invalidity ruling is estimated at 25–40%, this risk is significant and should weigh heavily in the analysis.
From the perspective of any future IP monetization strategy or portfolio licensing program, the walk-away preserves optionality. OWS's patents remain in force, and OWS retains the ability to license, cross-license, or assert them as business circumstances warrant. A post-walk-away updated valuation by Clearpath would likely reflect some downward adjustment to account for the adverse Markman constructions in this proceeding, but the adjustment would be far less severe than the impact of published invalidity rulings.
E. Stakeholder Implications
Vantage Point Capital Partners Fund IV, LP. As the majority shareholder of OWS with approximately 62% equity ownership, Vantage Point bears the predominant economic impact of the litigation costs and any recovery or lack thereof. The total litigation spend of $2,549,568 represents approximately 3.4% of Vantage Point's $74.5 million equity investment in OWS. While this is a meaningful sum, it is not material relative to Vantage Point's overall fund size and is within the range that was contemplated when the Board authorized the litigation. The walk-away avoids further expenditure of approximately $1.65 million with negligible recovery prospects, thereby preserving capital for OWS's core business operations, including the OWS-800LR chipset development program that is critical to OWS's near-term revenue growth trajectory. Vantage Point's primary concern, as communicated by Douglas Fairbanks III and Rebecca Torres, is the preservation of the IP portfolio and the avoidance of adverse validity rulings that could impair portfolio value for any future liquidity event (whether IPO, strategic sale, or portfolio licensing).
First Pacific Commerce Bank, N.A. ("FPCB"). OWS maintains a $40 million revolving credit facility with First Pacific Commerce Bank, N.A. The credit facility includes OWS's intellectual property assets as partial collateral under the security agreement. The loan covenants require notification to FPCB of material litigation developments and resolution of pending litigation. The walk-away avoids any risk of adverse invalidity findings that could impair the value of IP collateral and trigger covenant concerns. Upon acceptance of the walk-away, OWS should issue a notification letter to FPCB as required under the loan covenants, informing the bank of the resolution of the litigation. C&H will prepare a draft notification letter for Sandra Ellison's review and approval.
OWS Board of Directors. A clean resolution of this litigation allows the Board to refocus management attention on OWS's core business priorities. The Board has expressed concern about the time and attention that the litigation has diverted from the company's operational objectives, particularly the OWS-400ZR chipset volume ramp with key hyperscale customers and the OWS-800LR coherent chipset development program. The walk-away provides a clean break and eliminates any lingering uncertainty regarding the litigation's outcome.
IV. Option B: Continue Litigation Through Trial
A. Remaining Litigation Phases and Estimated Costs
If OWS rejects the walk-away and elects to continue litigating, the case will proceed through several remaining phases, each of which will generate substantial additional costs. The following cost estimates are based on C&H's experience in comparable patent cases in the Northern District of California, the specific circumstances of this case, and the anticipated intensity of the remaining proceedings.
Remaining Fact discovery — Estimated $250,000 to $350,000. Although fact discovery was substantially underway when the stipulated stay was entered, significant work remains. OWS has not yet completed its production of documents responsive to Lumos's 98 requests for production, and Lumos has indicated that it intends to serve supplemental requests targeting OWS's design documents, testing data, and communications with foundry partners relating to the accused products' architecture. In addition, several key depositions remain to be taken, including depositions of Lumos technical witnesses Dr. Mei-Lin Chen (Vice President of Photonic Design) and Dr. Nikolai Petrov (Director of Process Engineering), as well as Lumos business witness Jim Harrelson (Senior Vice President of Sales and Marketing). Third-party discovery directed at Drayton & Co. (OWS's fabrication partner) and Calderon Partners LLC (a Lumos supplier) is also contemplated. The cost estimate of $250,000 to $350,000 reflects attorney time for document review, deposition preparation and attendance, third-party subpoena practice, and associated travel and court reporter costs.
Expert discovery — Estimated $400,000 to $500,000. Expert discovery represents the single largest remaining cost category. OWS's technical expert, Dr. Harold Whitfield of Whitfield Technical Consulting Group, would need to prepare a comprehensive opening expert report on infringement (including any surviving doctrine-of-equivalents theories as to the '890 Patent), respond to Lumos's technical expert's non-infringement and invalidity reports, and sit for deposition. Similarly, OWS's damages expert, Dr. Lawrence Kessler of Apex Claim Analytics, would need to prepare an opening damages report (the methodology and conclusions of which would need to be substantially revised from his preliminary analysis in light of the Markman constructions), respond to the damages opinions of Dr. Patricia Moreno of Compass Forensic Accounting LLP (Lumos's damages expert), and sit for deposition. Expert fees alone (exclusive of attorney time for expert coordination, report review, and deposition preparation) are estimated at $200,000 to $275,000 for Dr. Whitfield and Dr. Kessler combined. The balance of the $400,000 to $500,000 estimate reflects attorney time for expert coordination, report drafting support, preparation for and attendance at expert depositions, and preparation and briefing of any Daubert motions.
Summary Judgment and Dispositive Motions — Estimated $200,000 to $300,000. Following the close of expert discovery, Lumos would almost certainly move for summary judgment of non-infringement under the Court's claim constructions as to all four patents. OWS would need to oppose these motions, though the prospects for defeating summary judgment on three of the four patents are poor given the clear exclusion of Lumos's accused product architectures under the Court's constructions. In addition, Lumos may move for summary judgment on its invalidity counterclaims, particularly as to the '567 Patent (based on the Tanaka reference and the Chen & Liu combination) and the '234 Patent (based on the Nordlicht reference). OWS would need to defend against these motions as well. The estimated cost of $200,000 to $300,000 reflects attorney time for briefing both offensive and defensive summary judgment motions, including supporting declarations, claim charts, expert declarations, and oral argument preparation.
Pre-Trial Preparation and Trial — Estimated $400,000 to $500,000. If the case survives summary judgment on any claim or counterclaim, the parties would proceed to trial. Judge Torvelis's current docket suggests a trial date in Q4 2023 or Q1 2024. A patent trial of this nature would typically last five to seven days. Pre-trial preparation would include preparation of proposed jury instructions, proposed verdict form, motions in limine, trial exhibit lists, witness lists, and trial demonstratives. Trial itself would require a team of at least three attorneys (lead counsel, second chair, and a junior associate for real-time support) plus a paralegal and a technical advisor. Witness preparation for OWS's fact and expert witnesses would be extensive. The estimated cost of $400,000 to $500,000 reflects all of these activities.
Total Estimated Remaining Costs.
For purposes of this analysis, we use the high-end estimate of $1,650,000 to ensure a conservative (worst-case from a cost perspective) analysis. It should be noted that this figure aligns almost precisely with the remaining balance of the Board-approved $4.2 million total litigation budget. After $2,549,568 in costs already incurred, the remaining budget is approximately $1,650,432 — essentially leaving no contingency margin for cost overruns, which are common in patent cases that proceed through trial. Any cost overruns beyond the budgeted amount would require additional Board approval and additional funding from OWS.
B. Probability of Recovery Assessment
1. Infringement Viability Post-Markman
The Markman Order has fundamentally undermined OWS's infringement theories. We assess each patent individually below:
'567 Patent — Infringement Untenable. The Court's construction of "adiabatically coupled" as requiring a "gradual, continuous taper designed and configured to prevent excitation of higher-order modes over the entire transition length" directly and unambiguously excludes Lumos's LumosBridge™ 800G Optical Engine, which employs a segmented (non-continuous) taper design with discrete coupling sections. Lumos's segmented taper is fundamentally different from a continuous taper: rather than gradually varying the waveguide geometry over a continuous transition, Lumos uses a series of discrete segments with abrupt geometric changes at each segment boundary. Under the Court's construction, this architecture cannot literally infringe.
The doctrine of equivalents does not provide a viable alternative theory. During prosecution of the '567 Patent, the applicant narrowed the claims to add the limitation "adiabatically coupled" specifically to overcome the Tanaka prior art reference (U.S. Patent No. 9,456,012), which disclosed a segmented coupler design. The prosecution history estoppel doctrine bars OWS from recapturing through the doctrine of equivalents the very subject matter that was surrendered during prosecution to obtain the patent. Festo Corp. v. Fenmore & Co., 535 U.S. 722 (2002). The narrowing amendment was directly responsive to the examiner's rejection based on Tanaka, and the applicant's remarks explicitly distinguished the claimed "adiabatic coupling" from Tanaka's segmented design. None of the narrow exceptions to prosecution history estoppel (unforeseeable, tangential, or other reason) apply here.
Infringement probability: Near zero.
'234 Patent — Infringement Untenable. The Court's construction of "graded buffer layer having a continuously varying germanium concentration" as requiring "a buffer layer in which the germanium atomic fraction increases monotonically and without step changes from the silicon substrate interface to the absorber layer" Squarely excludes Lumos's step-graded SiGe buffer. Lumos employs a buffer with four discrete composition steps at germanium atomic fractions of approximately 0.25, 0.50, 0.75, and 1.0. These are by definition "step changes" that are explicitly excluded by the construction. No reasonable jury could find literal infringement under this construction.
The doctrine of equivalents theory is similarly unavailing. The specification of the '234 Patent discloses both continuously graded and step-graded buffer embodiments. However, the claim language was limited to "continuously varying" — a term the Court found to be unambiguous in excluding step-graded designs. Under the doctrine of claim vitiation, OWS cannot use the doctrine of equivalents to effectively read the "continuously varying" limitation out of the claim. Applying the doctrine of equivalents to cover a step-graded buffer would render the "continuously varying" limitation meaningless, which is impermissible under Federal Circuit precedent. See Sage Prods., Inc. v. Devon Indus., Inc., 126 F.3d 1420, 1424 (Fed. Cir. 1997).
Infringement probability: Near zero.
'678 Patent — Infringement Untenable. The Court's construction of "monolithically formed on a single silicon die" as requiring fabrication "entirely within the same front-end-of-line and back-end-of-line semiconductor processing sequence on a single silicon substrate without heterogeneous bonding or attachment of separately fabricated optical components" explicitly excludes Lumos's manufacturing process for the LumosEdge™ 400ZR+ Pluggable Transceiver. Lumos utilizes micro-transfer-printed III-V (indium phosphide) gain elements — laser diodes and semiconductor optical amplifiers — that are fabricated on a separate InP wafer and then transferred and bonded to the silicon PIC substrate using a micro-transfer printing process. This process constitutes "heterogeneous bonding or attachment of separately fabricated optical components," which is the precise activity excluded by the Court's construction.
Prosecution history estoppel further forecloses any doctrine-of-equivalents argument. During prosecution, the applicant added the "monolithically formed" limitation to distinguish prior art references that disclosed hybrid integration approaches. The applicant's response to the examiner's office action stated: "The claimed invention is distinguished from heterogeneous integration approaches in which separately fabricated optical components are attached to or bonded to the silicon substrate. The claimed transceiver is monolithically formed, meaning all optical and electronic components are fabricated in the same semiconductor processing sequence on a single silicon substrate." This statement constitutes a clear and unambiguous surrender of all heterogeneous integration approaches, including micro-transfer printing.
Infringement probability: Near zero.
'890 Patent — Infringement Highly Unlikely. The Court's construction of "co-integrated" as requiring "fabrication in the same semiconductor process, sharing doping profiles and process layers, without bond wires, interposers, or package-level routing" excludes Lumos's architecture, which employs a separate CMOS driver die that is flip-chip bonded to the silicon PIC via copper pillar micro-bumps. The copper pillar micro-bumps constitute a form of die-to-die interconnect that is analogous to the "interposers" and "package-level routing" excluded by the Court's construction. Literal infringement is not provable.
However, unlike the three patents discussed above, the '890 Patent presents a narrow — though highly speculative — avenue for a doctrine-of-equivalents argument. The argument would be that Lumos's copper pillar micro-bump interconnects perform substantially the same function (providing electrical connectivity between the CMOS driver and the photonic IC), in substantially the same way (through metallic conductive pathways at the die interface), to achieve substantially the same result (enabling the CMOS driver to control the photonic components) as the co-integrated architecture claimed in the '890 Patent. The difficulty with this argument is threefold: (i) the prosecution history includes statements distinguishing the claimed co-integration from "multi-chip module" and "system-in-package" approaches, creating a colorable prosecution history estoppel argument; (ii) the function-way-result test may fail because Lumos's approach functions in a fundamentally different way (through separate fabrication and subsequent bonding rather than shared process fabrication); and (iii) there is a strong claim vitiation argument that applying the doctrine of equivalents to cover flip-chip bonded dies would effectively read the "without bond wires, interposers, or package-level routing" limitation out of the claim.
We estimate the probability of proving infringement on the '890 Patent under the doctrine of equivalents at no more than five percent, and even this estimate may be generous. The argument would face a hostile motion for summary judgment and, if it survived, a skeptical jury that would have heard Lumos's expert explain the fundamental architectural differences between true co-integration and flip-chip bonding.
Overall Assessment. The overall probability of proving infringement on at least one claim of at least one patent is estimated at less than five percent (< 5%). This probability is driven entirely by the speculative doctrine-of-equivalents theory on the '890 Patent; the other three patents present no viable infringement path.
2. Invalidity Risk
Lumos's counterclaims for invalidity under 35 U.S.C. §§ 102 and 103, and for unenforceability under 35 U.S.C. § 112, remain live and pose a meaningful risk to OWS's patent portfolio. The key prior art references and invalidity theories are as follows:
(a) '567 Patent — Tanaka (U.S. 9,456,012). Lumos contends that the '567 Patent is anticipated by the Tanaka reference, which discloses an adiabatic coupler with a continuous taper design for silicon waveguide mode conversion. Although the applicant distinguished Tanaka during prosecution by adding the "adiabatically coupled" limitation, the Court's Markman construction of "adiabatically coupled" is now closely aligned with the Tanaka disclosure, raising a renewed anticipation risk. In addition, Lumos asserts an obviousness theory under § 103 combining Tanaka with Chen & Liu (2016 journal article in Nature Photonics), which discloses optimization of taper geometry to suppress higher-order mode excitation. The combined teaching arguably renders the '567 Patent claims obvious.
(b) '234 Patent — Nordlicht (EP 3,234,567 A1). Lumos contends that the '234 Patent is anticipated or rendered obvious by the Nordlicht European patent application, which discloses a germanium photodetector formed on a silicon substrate using a graded SiGe buffer with a continuously varying germanium concentration. Lumos's technical expert has identified substantial overlap between the Nordlicht disclosure and the '234 Patent claims as construed, and the differences between the two may be insufficient to overcome an anticipation or obviousness challenge.
(c) '890 Patent — Iyer & Patel (2018 IEEE article). Lumos contends that the '890 Patent is anticipated or rendered obvious by a 2018 IEEE conference paper authored by Iyer and Patel, which discloses a co-integrated CMOS/photonic chipset fabricated in a shared semiconductor process on a single die. Lumos argues that Iyer & Patel teaches every limitation of the asserted claims of the '890 Patent and that the differences are merely variations in implementation detail that would have been obvious to one of ordinary skill in the art.
(d) All Patents — § 112 Defenses. Lumos has also asserted § 112 defenses (lack of written description and enablement) against all four patents, contending that the specifications fail to adequately describe and enable the claimed inventions with sufficient specificity to satisfy the written description and enablement requirements. While § 112 defenses in patent cases succeed less frequently than anticipation and obviousness defenses, they cannot be dismissed, particularly given the breadth of some of the claim language relative to the disclosed embodiments.
Overall Invalidity Risk. We estimate the probability that Lumos prevails on at least one invalidity counterclaim at 25–40%. This estimate reflects the strength of the Tanaka and Nordlicht prior art references, the vulnerability of the claims as now construed, and the general tendency of patent juries and courts in the Northern District of California to take invalidity arguments seriously. An adverse invalidity finding would be far more damaging to OWS than the walk-away because it would extinguish the affected patent(s) not only as against Lumos but as against all potential infringers worldwide.
3. Damages Risk Even If Infringement Proven
Even in the unlikely event that OWS were able to prove infringement on one or more claims of the '890 Patent (the only patent with any residual infringement theory), the damages recovery would be dramatically reduced from OWS's original expectations.
OWS's damages expert, Dr. Lawrence Kessler of Apex Claim Analytics, prepared a preliminary damages analysis in Q4 2022 that projected a reasonable royalty of approximately $75 million, based on a royalty rate of 7.5% applied to the full accused product revenue of approximately $148.6 million (CY 2022), with additional consideration given to forward-looking royalties through the remaining patent terms. This analysis was predicated on OWS's broader claim constructions, which would have covered all four of Lumos's accused product architectures across all four patents.
Under the Court's narrower claim constructions, if infringement were somehow proven on the '890 Patent alone under the doctrine of equivalents, the scope of that infringement would be minimal. The accused functionality — the "co-integration" of CMOS driver and photonic IC — represents only a portion of the value of the accused products, and the doctrine-of-equivalents infringement theory, if successful, would cover only the marginal overlap between the accused flip-chip bonding approach and the claimed co-integration, rather than the full accused product architecture. A realistic damages estimate under this scenario would be in the range of $2 million to $5 million — a fraction of the original $75 million claim. Dr. Kessler would need to substantially revise his analysis to account for the narrowed scope of infringement and the reduced royalty base, and even the revised analysis would face vigorous challenge from Lumos's damages expert, Dr. Patricia Moreno of Compass Forensic Accounting LLP.
Furthermore, willfulness enhancement (up to three times damages under 35 U.S.C. § 284) is effectively unavailable. The Markman Order provides Lumos with a strong, good-faith basis for its non-infringement position, and no reasonable jury or court would find willful infringement where the accused infringer's products were designed before the litigation and the claim constructions adopted by the Court support non-infringement on the literal terms. Lumos would also argue, persuasively, that even if some marginal doctrine-of-equivalents infringement were found, the de minimis scope of such infringement warrants only a nominal royalty.
C. Expected Value Calculation
The expected value of continued litigation is calculated by weighting the potential outcomes by their estimated probabilities and netting the result against the remaining litigation costs. This analysis demonstrates that the walk-away is the economically rational choice.
Scenario 1 — Best Case (Infringement Proven, Damages Awarded):
• Probability of proving infringement on at least one claim: < 5% (we use 5% for calculation purposes)
• Estimated recovery if infringement proven: $2 million to $5 million; midpoint $3.5 million
• Expected value of recovery: 5% × $3,500,000 = $175,000
Scenario 2 — Adverse Outcome (Invalidity Found, Potential Fee-Shifting):
• Probability that Lumos prevails on at least one invalidity counterclaim: 25–40%
• Probability that the Court makes an exceptional-case finding under § 285: 5–10% (we use 7.5% for calculation purposes)
• Lumos's estimated attorneys' fees through trial: $1.5 million to $2.5 million; midpoint $2 million
• Expected adverse exposure from fee-shifting: 7.5% × $2,000,000 = $150,000
Net Expected Value of Continued Litigation:
Conclusion. The expected value of continued litigation is approximately negative $1,625,000. Even under the most optimistic assumptions — using a 5% probability of recovery (which may be generous) and a midpoint recovery of $3.5 million (which assumes a favorable damages outcome that is itself highly uncertain) — the expected monetary outcome of continued litigation is deeply negative. The small positive expected recovery of $175,000 is overwhelmed by the combination of the expected adverse fee-shifting exposure and, more significantly, the certain $1.65 million in additional litigation costs that would be incurred regardless of the outcome.
The analysis confirms that the walk-away is the economically rational choice by a margin of approximately $1.6 million.
It should be noted that this expected value calculation does not assign any monetary value to the non-financial risks of continued litigation, including the risk of adverse invalidity rulings, the management distraction costs, the risk of adverse publicity, and the risk of impaired IP collateral value. If these factors were monetized, the expected value of continued litigation would be even more negative.
D. Non-Financial Risks of Continued Litigation
In addition to the negative expected financial value, continued litigation presents several significant non-financial risks:
Continued Management and Engineering Distraction. OWS is in a critical phase of its business. The OWS-800LR coherent chipset program is in pre-production qualification, and the company is ramping volume production of the OWS-400ZR chipset for hyperscale data center customers. Continued litigation would require ongoing time commitments from Dr. Priya Ramanathan, Dr. Kevin Fong, Sandra Ellison, Ted Marchetti, and key engineering personnel for an additional 12 to 18 months. This time has a significant opportunity cost that is not reflected in the financial analysis above.
discovery Burden. Lumos has served 98 requests for production of documents, and OWS's ongoing production obligations are substantial. The stipulated discovery stay temporarily relieved this burden, but if the walk-away is rejected and the stay lapses, OWS will be required to resume its document review and production efforts, including the review of technical design files, simulation data, foundry communications, and business development materials. This burden falls disproportionately on OWS's engineering staff, who are needed for product development.
Risk of Adverse Invalidity Rulings. As discussed in Section IV.B.2 above, there is a 25–40% probability that Lumos will prevail on at least one invalidity counterclaim. An adverse invalidity ruling — whether by summary judgment or at trial — would be a published decision that could be cited by future adverse parties in other proceedings involving OWS's patents. While invalidity determinations are technically limited to the specific claims at issue, as a practical matter, a published finding that one or more of OWS's patents is invalid based on specific prior art references could embolden other potential challengers to attack the same or related patents and could undermine OWS's ability to assert its portfolio in licensing negotiations.
Risk of Adverse Publicity. Lumos is a publicly traded company on the Nasdaq, and the outcome of this litigation may attract attention from industry analysts, trade press, and — most importantly — hyperscale data center customers who are potential or actual customers of both OWS and Lumos. An adverse jury verdict or a published opinion finding OWS's patents invalid could create negative perceptions of OWS's technology differentiation and intellectual property strength, potentially affecting OWS's competitive position in customer engagements.
Potential Negative Signal to FPCB. If continued litigation results in adverse invalidity findings, the value of OWS's IP collateral under the $40 million revolving credit facility with FPCB could be called into question. While it is unlikely that an adverse ruling on one or more patents would trigger a covenant default, it could create friction with FPCB and potentially affect the terms of any future refinancing or extension of the credit facility.
Continued Expert Costs. Dr. Harold Whitfield (Whitfield Technical Consulting Group) and Dr. Lawrence Kessler (Apex Claim Analytics) would need to prepare comprehensive opening and rebuttal expert reports, undergo depositions by Lumos's counsel, and potentially testify at trial. These engagements carry significant costs, as reflected in the budget estimates above, and also carry the risk that the experts' opinions may be challenged under Daubert, potentially resulting in the exclusion of critical testimony.
V. Comparative Summary Table
The following table provides a side-by-side comparison of the two options available to OWS:
The table makes clear that on every dimension — cost, expected recovery, risk, management burden, portfolio impact, and timeline — the walk-away is the superior outcome.
VI. Analysis of Alternative Settlement Structures
Before recommending acceptance of the walk-away as offered, we have considered whether alternative settlement structures might yield a better outcome for OWS. We have identified three theoretical alternatives and assess each below.
A. Cross-License with Nominal Royalty (Previously Proposed and Rejected)
On March 15, 2023, OWS proposed a settlement consisting of a cross-license covering OWS's full 87-patent portfolio and Lumos's patent portfolio, with a nominal $500,000 one-time royalty payment from Lumos to OWS, a mutual covenant not to sue on all current products, and a dismissal of the litigation with prejudice. Lumos rejected this proposal outright on approximately March 20, 2023.
Assessment: Not Achievable. Lumos has no incentive to enter into a cross-license arrangement. The Markman Order has effectively vindicated Lumos's independent design position, and Lumos's counsel, Victoria Ashworth of BHS, has communicated in no uncertain terms that Lumos views its products as non-infringing under the Court's claim constructions and sees no commercial need for a license to OWS's patents. From Lumos's perspective, paying even a nominal $500,000 royalty would constitute a concession that Lumos's products are within the scope of OWS's patents — a concession that Lumos is unwilling to make given its strong position post-Markman. Even a nominal $1 cross-license is unlikely to be achievable for the same reason: it implies that OWS's patents have some claim of relevance to Lumos's products, and Lumos does not wish to validate that implication. We do not recommend re-proposing this structure.
B. Walk-Away with Partial Cost Recovery
A theoretical alternative would be to ask Lumos to contribute to OWS's litigation costs as part of the walk-away settlement — for example, a $250,000 or $500,000 payment from Lumos to OWS in exchange for the mutual releases and dismissal.
Assessment: Not Achievable. Lumos would view any request for cost contribution as an attempt to extract nuisance value from a position of strength. Lumos holds the dominant litigation position following the Markman Order and has no incentive to pay OWS anything. Victoria Ashworth has communicated that the walk-away as proposed represents Lumos's final and best offer. If OWS were to push for a cost contribution, there is a material risk that Lumos would withdraw the walk-away offer entirely, terminate the settlement discussions, and proceed aggressively with dispositive motions — including summary judgment of non-infringement on all four patents and summary judgment on its invalidity counterclaims. We strongly advise against pursuing this alternative, as it risks losing the walk-away offer and triggering a resumption of litigation that would be costly and likely unsuccessful for OWS.
C. Walk-Away with Narrow License
Another theoretical alternative would be a walk-away with mutual releases plus a narrow license from Lumos to OWS under Lumos's patent portfolio, covering OWS's current products.
Assessment: No Value to OWS. OWS does not currently have an identified need for a license from Lumos. C&H and OWS's in-house IP team have not identified any Lumos patents that OWS's current products may infringe. Requesting such a license would add complexity to the settlement negotiations without providing tangible value and could be perceived by Lumos as an admission that OWS has infringement concerns regarding its own products — a perception that could create problems for OWS in the marketplace and in any future interactions with Lumos. We do not recommend pursuing this alternative.
D. Assessment: The Walk-Away as Offered Is the Best Available Outcome
Based on our analysis, the walk-away as proposed by Lumos on March 22, 2023, represents the best available settlement outcome for OWS. Lumos holds the stronger negotiating position by a wide margin following the Markman Order, and its walk-away offer is clean, straightforward, and free of any provisions that would disadvantage OWS. Any attempt by OWS to extract additional concessions — whether monetary, licensing, or otherwise — carries a meaningful risk of prolonging the litigation, increasing costs, and potentially losing the walk-away offer altogether.
The walk-away achieves the core objective of ending the litigation without further cost or risk, while preserving OWS's patent portfolio and eliminating the substantial downside risks of continued litigation. We recommend acceptance of the walk-away as offered, without further negotiation of terms.
VII. Impact on Fee Arrangement and Retainer
The following summarizes the financial status of the matter and the impact of the walk-away on C&H's fee arrangement and r