1014-00004 · Hawthorne Vega & Cruz LLP · Validity Defense Analysis

invalidity-analysis-015.docx DOCUMENT Litigation

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MEMORANDUM

PRIVILEGED AND CONFIDENTIAL — ATTORNEY WORK PRODUCT

To: Alan Ngo, Responsible Partner; Marcus Delgado, Billing Partner

From: Omar Siddiqui, Working Associate; Wendy Schultz, Lead Associate

Date: November 7, 2024

Re: Analysis of Lumicore Technologies, Inc.'s Invalidity Contentions for U.S. Patent No. 11,402,015 ("'015 Patent") — Prior-Conception Defense and Other Invalidity Theories

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

Classification: Attorney-Client Privileged / Attorney Work Product — Do Not Distribute Outside Case Team

This memorandum is protected by the attorney-client privilege and the work-product doctrine. It has been prepared at the direction of counsel and reflects the mental impressions, conclusions, opinions, and legal theories of the attorneys involved. It is intended solely for the use of the individuals identified above and other members of the case team as authorized by the responsible partner. Any unauthorized disclosure may result in waiver of applicable privileges.

I. EXECUTIVE SUMMARY

The purpose of this memorandum is to evaluate Lumicore Technologies, Inc.'s ("Lumicore") invalidity contentions as set forth in its P.R. 3-3 Invalidity Contentions served on October 14, 2024, as they pertain specifically to U.S. Patent No. 11,402,015 (the "'015 Patent"), entitled "Polarization-Diverse Grating Coupler for Silicon Photonic Transceivers." This memorandum analyzes each invalidity theory asserted by Lumicore, evaluates the strength and weakness of the supporting evidence, and provides strategic recommendations for responding to these contentions through discovery, expert preparation, dispositive motions, and trial strategy.

Our key conclusion is as follows: Lumicore's primary invalidity theory for the '015 Patent is a prior-conception defense based on Lumicore's own internal design documents purportedly dated between late 2016 and early 2017. This defense is, in our assessment, the weakest of the invalidity theories asserted across all four asserted patents in this litigation. The defense suffers from several fundamental infirmities. First, the internal documents Lumicore relies upon lack adequate corroboration, as required by well-established Federal Circuit precedent governing prior-conception claims. Second, the documents present serious credibility issues regarding their dating and authorship, including a critical metadata inconsistency in which a Northgate Services Inc. presentation claimed to have been created in January 2017 reflects a "last modified" date of March 2019 — nearly two years after our client Optiwave Semiconductor Corp.'s ("OWS") April 7, 2017 provisional filing date. Third, the defense faces a threshold legal obstacle under the America Invents Act ("AIA") first-inventor-to-file framework, because unpublished internal documents do not constitute prior art under 35 U.S.C. § 102(a)(1) or (a)(2), and Lumicore has not raised a derivation proceeding or clearly articulated any other viable statutory basis for its theory. For these reasons, the prior-conception defense likely cannot survive summary judgment.

In addition to the prior-conception defense, Lumicore asserts obviousness under 35 U.S.C. § 103 by combining certain prior-art references, principally the Bergmann patent (U.S. Patent No. 8,412,007) and the Simonsen PCT application (PCT/EP2015/071234). These combination arguments are addressed in detail below and are found to present moderate but manageable risk. Notably, this exact Bergmann-Simonsen combination was considered by the USPTO examiner during prosecution of the '015 Patent and was overcome through a narrowing amendment and accompanying arguments. The fact that the examiner considered and ultimately rejected this combination before allowing the claims significantly strengthens the presumption of validity and increases the evidentiary burden Lumicore must satisfy.

Our overall risk assessment is that the '015 Patent presents a low risk of being found invalid. Among the four asserted patents in this litigation — the '847 Patent, the '193 Patent, the '562 Patent, and the '015 Patent — the '015 Patent has the strongest validity posture. This assessment is reinforced by the robust secondary considerations of non-obviousness that OWS can present, including substantial commercial success of products practicing the '015 Patent claims, evidence of copying by Lumicore, long-felt but unresolved need in the silicon photonics industry for efficient polarization-diverse coupling solutions, and the failure of other competitors to achieve comparable results prior to OWS's innovation.

This memorandum should be read in conjunction with the companion Invalidity Contentions Analysis memos prepared for the other three asserted patents: the '847 Patent (November 1, 2024), the '193 Patent (November 3, 2024), and the '562 Patent (November 5, 2024). This memorandum also cross-references the comprehensive Prosecution History Review — All Asserted Patents (September 2024), the PHE Analysis — '015 Patent (October 12, 2024), and the IPR Risk Assessment Memorandum (May 15, 2024), each of which addresses related issues relevant to the analysis herein.

II. BACKGROUND ON THE '015 PATENT

A. Patent Overview

U.S. Patent No. 11,402,015 is entitled "Polarization-Diverse Grating Coupler for Silicon Photonic Transceivers." The patent discloses and claims a grating coupler architecture designed to address one of the persistent challenges in silicon photonics: efficiently coupling light of both transverse electric ("TE") and transverse magnetic ("TM") polarization states into and out of silicon photonic waveguides. The claimed architecture employs a two-dimensional sub-wavelength grating structure that achieves polarization-diverse coupling without the need for a separate external polarization-splitting element, representing a significant advance over prior one-dimensional grating coupler designs that were inherently polarization-dependent.

The relevant bibliographic and prosecution data for the '015 Patent is as follows:

• Patent Number: U.S. Patent No. 11,402,015

• Title: "Polarization-Diverse Grating Coupler for Silicon Photonic Transceivers"

• Filing Date: August 30, 2019

• Issue Date: August 2, 2022

• Current Assignee: Optiwave Semiconductor Corp.

• Original Assignee: Optiwave Semiconductor Corp.

• Named Inventors: Dr. Jian-Wei Huang (Chief Technology Officer, OWS) and Dr. Nikolai Petrov (Vice President of Engineering, Photonics Division, OWS)

• Priority Claim: The '015 Patent claims the benefit of Provisional Application No. 62/499,117, filed April 7, 2017. This provisional application is shared with the '193 Patent (U.S. Patent No. 10,891,193).

• Effective Priority Date: April 7, 2017, the filing date of the provisional application.

• Patent Family: The '015 Patent and the '193 Patent both claim priority to Provisional Application No. 62/499,117. However, the two patents are not in a continuation relationship with one another; they were filed as separate non-provisional applications, each claiming independent priority to the same provisional. The '015 Patent is directed to the grating coupler architecture itself, while the '193 Patent is directed to the broader transceiver system incorporating that architecture.

• Prosecution Firm: Cascade IP Advisors, LLC (Lead Prosecution Attorney: Dr. Martin Chu, Reg. No. 52,341, 1550 Crystal Drive, Suite 600, Arlington, VA 22202)

• Maintenance Fees: All maintenance fees are current through the next due date.

The provisional application filed on April 7, 2017 disclosed the polarization-diverse grating coupler concept in substantial detail, including experimental results from prototype devices fabricated on OWS's silicon photonic platform. The provisional disclosed the two-dimensional sub-wavelength grating structure, polarization-splitting functionality, and coupling-efficiency measurements for both TE and TM modes. The non-provisional application filed on August 30, 2019 expanded upon the provisional disclosures with additional embodiments and refined claim language.

B. Asserted Claims

OWS asserts Claims 1, 5, 8, 12, and 16 of the '015 Patent against Lumicore in this litigation. These claims are briefly summarized as follows:

Claim 1 is an independent claim directed to a polarization-diverse grating coupler capable of coupling light of two orthogonal polarization states in a silicon photonic transceiver. Claim 1 recites the fundamental structural and functional elements of the coupler, including the grating structure formed on a silicon substrate, the coupling of both TE and TM polarization modes, and the integration of the coupler with a silicon photonic waveguide. This is the broadest of the asserted claims and establishes the foundational scope of the patented invention.

Claim 5 depends from Claim 1 and adds specific structural features related to the grating coupler geometry. In particular, Claim 5 recites dimensional parameters and periodic structural characteristics of the grating elements that contribute to the coupler's polarization-diverse functionality. These additional limitations narrow the claim scope by requiring particular physical configurations not generically required by Claim 1.

Claim 8 also depends from Claim 1 and specifies coupling-efficiency parameters. Claim 8 requires that the grating coupler achieve specified minimum coupling efficiencies for both TE and TM polarization modes, expressed as numerical thresholds. This performance-based limitation further narrows the claim scope and is relevant to the infringement analysis because it ties the claim to measurable performance metrics of the accused products.

Claim 12 is the second independent claim and is of particular significance in this litigation. Claim 12 recites a specific "two-dimensional sub-wavelength grating" limitation, specifying the structural characteristics of the grating in greater detail than Claim 1. Claim 12 is the claim for which OWS also asserts infringement under the doctrine of equivalents with respect to certain features of the LumiEdge 1600G-LR product. As discussed below, Claim 12 was the subject of a narrowing amendment during prosecution to distinguish over the Bergmann-Simonsen prior-art combination, which has prosecution history estoppel implications for the doctrine of equivalents assertion. These estoppel implications are analyzed in the separate PHE Analysis — '015 Patent memorandum dated October 12, 2024.

Claim 16 depends from Claim 12 and further specifies characteristics of the polarization-splitting element integrated within the two-dimensional sub-wavelength grating. Claim 16 imposes additional structural and functional constraints on the splitting element's geometry and its relationship to the grating's sub-wavelength features.

C. Accused Products

OWS accuses the following Lumicore products of infringing the asserted claims of the '015 Patent:

LumiLink 800G-DR8. This product was launched by Lumicore in Q1 2023 and is Lumicore's flagship 800-gigabit-per-second data-rate silicon photonic transceiver module designed for data center interconnect applications. According to Lumicore's public filings and financial disclosures, the LumiLink 800G-DR8 generated approximately $128.4 million in revenue during FY 2023. OWS accuses this product of infringing Claims 1, 5, 8, 12, and 16 of the '015 Patent based on the polarization-diverse grating coupler architecture incorporated in its silicon photonic engine. The Benchmark Semiconductor Analysis teardown report dated June 2023 confirmed the presence of a two-dimensional grating coupler structure consistent with the '015 Patent claims.

LumiEdge 1600G-LR. This product was launched by Lumicore in Q4 2023 and represents Lumicore's next-generation 1.6-terabit-per-second long-reach transceiver module. The LumiEdge 1600G-LR generated approximately $41.7 million in revenue during FY 2023 (reflecting only a partial year of sales following its Q4 launch). OWS accuses this product of infringing Claims 1, 5, 8, 12, and 16 of the '015 Patent. The Benchmark Semiconductor Analysis teardown report dated February 2024 identified a grating coupler architecture in the LumiEdge that shares key structural features with the LumiLink design but incorporates certain modifications. It is with respect to these modifications in the LumiEdge product that OWS additionally asserts infringement of Claim 12 under the doctrine of equivalents.

It is noteworthy that the LumiLink 400G-ZR+ — which is accused of infringing certain claims of the other asserted patents in this litigation — is not accused of infringing the '015 Patent. The 400G-ZR+ employs a different, conventional one-dimensional grating coupler design that does not meet the "polarization-diverse" limitations of the '015 Patent claims. This product-specific distinction is relevant to Lumicore's prior-conception defense, as discussed in Section IV.C below.

D. Prosecution History Summary Relevant to Invalidity

The prosecution history of the '015 Patent is directly relevant to the invalidity analysis, particularly with respect to Lumicore's obviousness contentions based on the Bergmann-Simonsen combination. The key events in the prosecution history are summarized as follows:

Provisional Application No. 62/499,117 was filed on April 7, 2017 by the named inventors, Dr. Jian-Wei Huang and Dr. Nikolai Petrov, through Cascade IP Advisors, LLC. The provisional disclosed the polarization-diverse grating coupler concept with accompanying experimental results, including fabrication data and coupling-efficiency measurements obtained from prototype devices. The provisional application establishes April 7, 2017 as the effective priority date for the '015 Patent claims.

The non-provisional application was filed on August 30, 2019, with an express priority claim to Provisional Application No. 62/499,117. The non-provisional expanded upon the provisional disclosures with additional embodiments and detailed claim language directed to the specific structural and functional features of the polarization-diverse grating coupler.

During prosecution, the USPTO examiner issued a rejection under 35 U.S.C. § 103, asserting that the claims were obvious in view of the combination of the Bergmann patent (U.S. Patent No. 8,412,007, issued April 2, 2013) and the Simonsen PCT application (PCT/EP2015/071234, published September 17, 2015). The examiner's rejection asserted that Bergmann's disclosure of a grating coupler structure, when combined with Simonsen's teaching of polarization management in optical coupling arrangements, rendered the claimed polarization-diverse grating coupler obvious to a person of ordinary skill in the art.

In response to the examiner's rejection, the applicants — represented by Dr. Martin Chu of Cascade IP Advisors — took a two-pronged approach. First, the applicants amended Claim 12 to narrow the "two-dimensional sub-wavelength grating" limitation by specifying particular structural characteristics that distinguished the claimed grating from both Bergmann's one-dimensional grating coupler and Simonsen's polarization management arrangement. Second, the applicants submitted detailed arguments and a Declaration explaining that neither Bergmann nor Simonsen, alone or in combination, disclosed or suggested a two-dimensional sub-wavelength grating integrated within a silicon photonic transceiver to achieve simultaneous coupling of orthogonal polarization states. The applicants argued that a person of ordinary skill in the art would not have been motivated to combine these references to arrive at the claimed invention, because the references addressed fundamentally different coupling architectures and the technological barriers to implementing polarization-diverse sub-wavelength gratings on silicon substrates were substantial.

The examiner was persuaded by the amendment and arguments, and the claims were allowed. The patent issued on August 2, 2022.

This prosecution history is significant for two reasons. First, the examiner's consideration and rejection of the Bergmann-Simonsen combination strengthens the presumption of validity under 35 U.S.C. § 282 with respect to any invalidity challenge based on that same combination. Second, the narrowing amendment to Claim 12 has implications for prosecution history estoppel under the doctrine of equivalents, which is addressed in the separate PHE Analysis — '015 Patent memorandum dated October 12, 2024. For purposes of this invalidity analysis, the key takeaway is that the Bergmann-Simonsen combination was squarely before the examiner and was found insufficient to render the claims unpatentable.

III. SUMMARY OF LUMICORE'S INVALIDITY CONTENTIONS FOR THE '015 PATENT

A. Overview of Theories Asserted

Lumicore's P.R. 3-3 Invalidity Contentions, served on October 14, 2024, assert invalidity of the '015 Patent on three separate grounds:

1. Prior conception and reduction to practice by Lumicore (primary theory). Lumicore contends that the subject matter of the asserted claims of the '015 Patent was conceived by Lumicore engineers prior to OWS's April 7, 2017 provisional filing date. Lumicore identifies a collection of internal design documents purportedly dated between late 2016 and early 2017 as evidence of this prior conception. Lumicore further contends that it exercised reasonable diligence toward reducing its conception to practice, pointing to internal R&D milestone reports from 2017 and 2018.

2. Obviousness under 35 U.S.C. § 103 — Bergmann combined with Simonsen. Lumicore contends that the asserted claims would have been obvious in view of the Bergmann patent (U.S. Patent No. 8,412,007) in combination with the Simonsen PCT application (PCT/EP2015/071234), and potentially in further combination with other references. This is the same combination that was considered and rejected by the examiner during prosecution.

3. Obviousness under 35 U.S.C. § 103 — Academic publications combined with known design principles. Lumicore contends that certain academic publications on grating coupler design, when combined with known grating coupler design principles and the general state of the art, render the asserted claims obvious. The specific academic references are identified in Section V.B below.

Notably, Lumicore does not assert anticipation under 35 U.S.C. § 102 against the '015 Patent. This stands in contrast to Lumicore's approach to the '847 Patent and '562 Patent, where anticipation by specific prior-art references is a primary invalidity theory. The absence of an anticipation theory against the '015 Patent is itself indicative of the relative strength of this patent's validity position, as it suggests that Lumicore was unable to identify any single reference that discloses all limitations of any asserted claim.

The prior-conception defense is novel in the context of this litigation and raises unique evidentiary and legal issues that are distinct from the prior-art challenges asserted against the other three asserted patents. As discussed in detail in Section IV, this defense confronts significant obstacles under both the AIA statutory framework and the corroboration requirement established by Federal Circuit precedent.

B. Prior-Conception Defense — Lumicore's Identified Evidence

In its P.R. 3-3 contentions, Lumicore identifies the following four categories of internal documents as purported evidence of prior conception:

First, Lumicore identifies internal design notebook entries attributed to Dr. Eric Dalmqvist, Vice President of Product Development at Lumicore. These entries are purportedly dated from November 2016 through February 2017. The entries consist of handwritten notes and sketches reflecting design concepts for a polarization-diverse coupling structure. Lumicore contends that these entries document the conception of the claimed grating coupler architecture during this timeframe.

Second, Lumicore identifies an internal Northgate Services Inc. presentation titled "Next-Gen Grating Coupler Architecture," which Lumicore claims was created in January 2017. The presentation is attributed to Lumicore's photonics design group and consists of 22 slides marked "Lumicore Technologies — Confidential." Lumicore contends the presentation demonstrates that the photonics design group had developed the claimed coupler concept as of January 2017.

Third, Lumicore identifies an email chain among Lumicore engineering staff, including Dr. Sandra Michaud (who was a senior engineer at Lumicore at the time and is now Lumicore's Chief Technology Officer). The email chain is dated December 2016 and discusses polarization-diverse coupler concepts. Lumicore contends this email chain demonstrates that the relevant technical concepts were under active discussion within Lumicore's engineering team prior to OWS's priority date.

Fourth, Lumicore identifies annotated schematic drawings of a two-dimensional grating structure. These drawings are undated, but Lumicore claims they were created in Q4 2016. Lumicore contends the drawings depict a grating structure consistent with the claimed invention.

Lumicore's contentions assert that these documents, collectively, demonstrate conception of the subject matter of Claims 1, 5, 8, 12, and 16 of the '015 Patent prior to OWS's April 7, 2017 provisional filing date. Lumicore further contends that it exercised reasonable diligence toward reduction to practice, pointing to internal R&D milestone reports from 2017 and 2018 that purportedly document ongoing development of the grating coupler technology.

C. Obviousness Theories — Prior-Art References Cited Against the '015 Patent

Among the 23 total prior-art references cited by Lumicore across all four asserted patents, the following references are specifically cited in the invalidity contentions against the '015 Patent:

U.S. Patent No. 8,412,007 (Bergmann), issued April 2, 2013. The Bergmann patent is directed to grating coupler structures for optical interconnects. It discloses a one-dimensional grating coupler with efficiency optimization techniques, including specific grating period designs and apodization methods aimed at improving the coupling efficiency between an optical fiber and a planar waveguide. Importantly, Bergmann does not disclose polarization diversity — that is, Bergmann's grating coupler is designed to couple a single polarization state (TE mode) and does not address the challenge of simultaneously coupling both TE and TM polarization modes. Bergmann also does not disclose a two-dimensional sub-wavelength grating structure.

PCT/EP2015/071234 (Simonsen), published September 17, 2015. The Simonsen PCT application is directed to an optical coupling arrangement with polarization management capabilities. Simonsen teaches the use of polarization-splitting elements in fiber-to-chip coupling, but in the context of a free-space optical system rather than a silicon photonic transceiver with integrated grating couplers. The polarization management approach described by Simonsen employs discrete optical components (e.g., beam splitters and waveplates) that are fundamentally different from the monolithically integrated two-dimensional grating coupler architecture claimed in the '015 Patent.

Lumicore also cites additional academic references on grating coupler design, including conference papers and journal articles discussing two-dimensional gratings in various optics contexts. These references are discussed in Section V.B below. In general, these academic references establish that two-dimensional grating structures were known in the broader field of optics but do not teach the specific application of such structures to polarization-diverse coupling in silicon photonic transceivers as claimed in the '015 Patent.

It is significant that Lumicore's obviousness combinations largely track the same Bergmann-Simonsen combination that was considered and rejected by the USPTO examiner during prosecution. While Lumicore supplements this combination with additional academic references, the core theory remains substantially the same as the rejected theory. This overlap is highly relevant to the strength of the presumption of validity and the evidentiary burden Lumicore must carry at trial.

IV. ANALYSIS OF PRIOR-CONCEPTION DEFENSE

A. Legal Framework — Prior Conception and Reduction to Practice Under the AIA

The legal framework applicable to Lumicore's prior-conception defense requires careful analysis, because this defense raises a threshold statutory question under the AIA that Lumicore's contentions do not adequately address.

The '015 Patent has an effective filing date of August 30, 2019 (the non-provisional filing date) with a priority date of April 7, 2017 (the provisional filing date). Because the effective filing date of the '015 Patent is after March 16, 2013, the patent is subject to the AIA's first-inventor-to-file provisions, codified at 35 U.S.C. § 102(a) as amended by the AIA. Under the AIA framework, the prior-art provisions differ materially from the pre-AIA first-to-invent regime, and these differences have direct implications for the viability of Lumicore's prior-conception defense.

Under AIA § 102(a)(1), "[a] person shall be entitled to a patent unless . . . the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention." Under AIA § 102(a)(2), a U.S. patent or published application constitutes prior art as of its effective filing date. The critical phrase in § 102(a)(1) for present purposes is "otherwise available to the public." Under the AIA's legislative history and subsequent case law, § 102(a)(1) was intended to create a unitary standard requiring public availability. See H.R. Rep. No. 112-98, at 42-43 (2011) (explaining that the phrase "available to the public" was added to "set forth an overarching requirement" for prior art status).

Lumicore's internal documents — the design notebook entries, Northgate Services Inc. presentation, email chain, and annotated schematics — are by their nature unpublished, confidential corporate records that were never made available to the public. They were not patented, described in a printed publication, in public use, on sale, or otherwise available to the public at any time before the '015 Patent's effective priority date. Accordingly, they cannot constitute prior art under § 102(a)(1). They likewise cannot constitute prior art under § 102(a)(2), because they are not U.S. patents, published applications, or WIPO publications.

This presents a fundamental obstacle to Lumicore's prior-conception defense. Under the pre-AIA first-to-invent regime, a defendant could defeat a patent by establishing that it (or another party) had independently conceived and reduced to practice the claimed invention before the patentee's date of invention, thus establishing prior inventorship. See 35 U.S.C. § 102(g) (pre-AIA). Under that regime, unpublished internal documents could be relevant as evidence of prior inventorship. However, § 102(g) was eliminated by the AIA, and the first-inventor-to-file system replaced the first-to-invent system for all patents with effective filing dates on or after March 16, 2013.

Lumicore's characterization of its theory as a "prior-conception defense" thus appears to conflate pre-AIA and AIA concepts. Under the AIA, there is no statutory defense based on prior conception alone. The available theories under which Lumicore might attempt to utilize its internal documents are limited and problematic:

Derivation under 35 U.S.C. § 135. The AIA replaced the pre-AIA interference proceedings with a derivation proceeding, which allows a party to challenge a patent by showing that the named inventor derived the claimed invention from another inventor. However, a derivation proceeding must be filed within one year of the first publication of the challenged claim. See 35 U.S.C. § 135(a). More critically, Lumicore has not raised a derivation theory in this litigation, and a derivation proceeding is brought before the Patent Trial and Appeal Board, not in district court litigation. To the extent Lumicore might argue derivation as a defense, it would need to establish not only that it conceived the invention first, but that the OWS inventors derived the invention from Lumicore — a theory for which Lumicore's contentions offer no factual support whatsoever. There is no allegation that the OWS inventors had access to Lumicore's internal documents or that any information flowed from Lumicore to OWS.

Prior commercial use defense under 35 U.S.C. § 273. The AIA expanded the prior commercial use defense, which permits a party to assert as a defense that it commercially used the subject matter of a patent in the United States at least one year before the effective filing date of the patent or the date of disclosure to the public, whichever is earlier. However, § 273 is an infringement defense, not an invalidity defense. A successful assertion of the § 273 defense does not render the patent invalid; it merely entitles the defendant to continue its prior commercial use. Moreover, the § 273 defense requires actual commercial use — not merely conception or internal documentation — and Lumicore's contentions do not allege that any commercial product embodying the claimed invention was in use before the '015 Patent's priority date. As noted above, Lumicore's first accused product (the LumiLink 800G-DR8) was not launched until Q1 2023, more than five years after the priority date.

General invalidity under 35 U.S.C. § 102(a)(1). As discussed above, this theory fails because Lumicore's internal documents were not publicly available. If Lumicore contends that any aspect of the designs reflected in these documents was disclosed to third parties or otherwise made publicly available before the priority date, its contentions do not clearly identify any such public disclosure. The documents are uniformly described as internal and confidential.

In sum, Lumicore's legal theory for using unpublished internal documents as a basis for invalidity is, at best, strained under the AIA framework. The most viable statutory vehicle — the prior commercial use defense under § 273 — is an infringement defense rather than an invalidity defense, and it requires commercial use that Lumicore has not alleged. Lumicore's characterization of its theory as a "prior-conception defense" reflects a fundamental misapprehension of the AIA statutory scheme, or at least a failure to articulate a coherent legal theory within that scheme. This threshold deficiency is itself a basis for seeking summary judgment on this defense, and it should be raised at the earliest opportunity.

B. Corroboration Requirement

Even setting aside the threshold AIA statutory issue, Lumicore's prior-conception defense is subject to the well-established corroboration requirement. Under Federal Circuit precedent, a party asserting prior conception must provide evidence of conception that is corroborated by evidence independent of the alleged inventor's own testimony. See Mahurkar v. C.R. Bard, Inc., 79 F.3d 1572, 1577-78 (Fed. Cir. 1996); Price v. Symsek, 988 F.2d 1187, 1194 (Fed. Cir. 1993). The corroboration requirement is applied using a "rule of reason" analysis, under which all pertinent evidence is considered to determine whether the inventor's testimony is credible. See Reese v. Hurst, 661 F.2d 1222, 1225 (Fed. Cir. 1981). Physical evidence, such as contemporaneous documents with verifiable dates, laboratory records with corroborating witness signatures, and third-party testimony, provides the strongest form of corroboration. Self-serving testimony by interested witnesses, particularly current employees of a party asserting the defense, is entitled to diminished weight.

We analyze each category of Lumicore's identified documentary evidence below against the corroboration requirement.

1. Design Notebook Entries (Dr. Eric Dalmqvist, November 2016 – February 2017)

Lumicore produced copies of notebook pages attributed to Dr. Eric Dalmqvist, Lumicore's Vice President of Product Development, during discovery. These pages purportedly span from November 2016 through February 2017 and contain handwritten notes and sketches relating to polarization-diverse coupler design concepts.

Our review of the produced copies reveals several significant issues that undermine the corroborative value of these notebook entries:

First, the notebook pages are not from a bound, paginated laboratory notebook with sequential page numbering. Standard scientific and engineering practice — and standard corporate intellectual property policies — typically require that invention disclosures and design concepts be recorded in bound notebooks with pre-numbered pages to prevent insertion, removal, or rearrangement of pages. Instead, the pages produced by Lumicore appear to be loose-leaf pages that were inserted into a ring binder. This format makes it impossible to verify the sequence in which the pages were created and eliminates the integrity safeguard that bound notebooks provide.

Second, none of the notebook pages bears a countersigning witness signature or a witness attestation date. It is standard practice in the research and development context, particularly for companies engaged in technology development in patent-intensive fields, for notebook entries to be reviewed and countersigned by a second person — typically a colleague who did not participate in the inventive work — to provide independent verification of the date and content of the entry. The complete absence of any such countersignatures from any page in Dr. Dalmqvist's purported notebook is a glaring corroboration deficiency.

Third, Lumicore has produced no chain-of-custody documentation for the notebook. In response to OWS's document requests, which specifically sought chain-of-custody documentation, retention records, and storage history for all documents identified in Lumicore's invalidity contentions, Lumicore produced no responsive materials pertaining to the Dalmqvist notebook. This absence raises questions about when the notebook was compiled, whether pages were added or removed at any point, and whether the notebook was maintained in a manner consistent with the claimed dates.

Fourth, Dr. Dalmqvist's deposition has not yet been taken. His deposition is currently scheduled for Q1–Q2 2025, and his testimony regarding the dating, context, authorship, and chain of custody of these notebook entries will be critical to assessing their evidentiary value. At this stage, the notebook entries are entirely self-serving records of a current Lumicore employee who has a direct interest in the outcome of this litigation, and no independent corroboration of their dating or authenticity has been provided.

Fifth, we have not yet completed a forensic analysis of the electronic scans of the notebook pages that were produced in Lumicore's document production. We recommend engaging a forensic document examiner to analyze the ink composition, paper dating, and any other physical characteristics of the original notebook pages if this defense gains traction. Additionally, a comparison of the electronic scan metadata with the claimed creation dates may yield useful information.

The key vulnerability of the notebook entries is clear: without any corroborating witness testimony, countersigning attestation, chain-of-custody records, or forensic verification, the self-serving nature of these entries — created or maintained by a current Lumicore executive with direct responsibility for the accused products — significantly undermines their evidentiary weight. Under the corroboration requirement, these entries alone cannot satisfy Lumicore's burden.

2. Internal Northgate Services Inc. Presentation ("Next-Gen Grating Coupler Architecture," January 2017)

The second category of evidence is a 22-slide Northgate Services Inc. presentation marked "Lumicore Technologies — Confidential" and titled "Next-Gen Grating Coupler Architecture." Lumicore claims this presentation was created in January 2017 by Lumicore's photonics design group.

Our review of this document and its metadata reveals the following issues:

The most significant issue is a critical metadata inconsistency. The file metadata for the Northgate Services Inc. presentation shows a "last modified" date of March 2019. This date is nearly two years after OWS's April 7, 2017 provisional filing date, which serves as the priority date for the '015 Patent. The March 2019 "last modified" date raises a serious and substantiated question as to whether the document was altered, updated, or re-saved after the priority date. If the content of the presentation was modified in March 2019, then its evidentiary value as proof of what Lumicore conceived prior to the priority date is fatally compromised. The content of the presentation as it exists today may reflect post-priority-date revisions that incorporate knowledge of OWS's published patent application or other post-priority-date developments.

The file metadata does show a "created" date of January 12, 2017, which facially supports Lumicore's claimed creation date. However, the "created" date field in Ashbury Holdings Northgate Services Inc. metadata is readily manipulable and is not dispositive of the actual creation date. A file's "created" date can be changed by modifying the file's properties, by using the "Save As" function in a manner that resets certain metadata fields, or by other means. Moreover, the discrepancy between the "created" date (January 2017) and the "last modified" date (March 2019) itself demands explanation: if the file was truly created in January 2017 and never modified, the "last modified" date should reflect the same or a closely proximate date.

Additionally, the presentation lacks any internal distribution records. No email has been produced in which the Northgate Services Inc. file was attached or forwarded with a pre-priority-date timestamp. Without such contemporaneous distribution evidence, there is no independent verification that the presentation existed in its current form at any time before OWS's priority date.

On the substance, our content analysis of the 22 slides reveals that the presentation discusses general polarization-diversity concepts and surveys various grating coupler architectures at a high level. However, the specific two-dimensional sub-wavelength grating structure claimed in Claim 12 of the '015 Patent is not disclosed in the presentation. The coupler designs shown in the slides are conventional one-dimensional grating couplers with polarization-splitting elements positioned at the output, which represents a materially different architecture from the claimed invention. The '015 Patent's innovation lies in achieving polarization diversity within the grating coupler structure itself through a two-dimensional sub-wavelength design — not through separate downstream polarization-splitting elements. The presentation does not disclose this integrated approach.

Even if the Northgate Services Inc. presentation is accepted as authentic and pre-dating OWS's priority date — which the metadata inconsistency calls into serious doubt — the presentation does not disclose all limitations of any asserted claim. At most, it demonstrates that Lumicore was aware of and interested in the general concept of polarization-diverse coupling, which is not the same as conception of the specific invention claimed in the '015 Patent.

3. Email Chain (December 2016)

The third category of evidence is an email chain among Lumicore engineering staff, including Dr. Sandra Michaud (who was then a senior engineer at Lumicore and has since been promoted to Chief Technology Officer). The email chain is dated December 2016 and discusses polarization-diverse coupler concepts.

The email chain was produced from Lumicore's email archives, and the email metadata appears facially consistent with December 2016 dates. Of the four categories of Lumicore's documentary evidence, this is the only one with metadata that does not present an obvious inconsistency. However, the substance of the emails significantly limits their evidentiary value.

Our review reveals that the emails discuss polarization-diverse coupling in general terms, reflecting a high-level technical discussion among engineers about emerging trends and design possibilities in the field. One email references "exploring 2D grating concepts" in the context of identifying research areas for future investigation. However, the emails do not disclose any specific structure, dimensions, materials, design parameters, or implementation approach for a two-dimensional sub-wavelength grating coupler. They do not include any drawings, schematics, or simulation results. They do not describe a definite and permanent idea of a complete and operative invention. At most, the emails constitute evidence of interest in the general field — not evidence of conception of the specific invention claimed in the '015 Patent.

The legal standard for conception requires "the formation in the mind of the inventor of a definite and permanent idea of the complete and operative invention, as it is hereafter to be applied in practice." Hybritech Inc. v. Monoclonal Antibodies, Inc., 802 F.2d 1367, 1376 (Fed. Cir. 1986). A general interest in a technical field, or even a stated intention to explore a particular design approach, does not constitute conception under this standard. The December 2016 emails fall far short of demonstrating that any Lumicore engineer had formed a definite and permanent idea of the polarization-diverse grating coupler architecture claimed in the '015 Patent.

Furthermore, Dr. Michaud's testimony from her November 19, 2024 deposition is highly relevant to the evidentiary significance of this email chain. During her deposition, Dr. Michaud admitted that the Lumicore engineering team reviewed OWS's published patent application No. 2018/0123456 — which corresponds to the '193 Patent and shares the same provisional application as the '015 Patent — during the design phase of the LumiLink product line in 2021–2022. This admission supports an inference that Lumicore's later design work on the grating coupler architecture in its accused products was influenced by OWS's published disclosures rather than by these early December 2016 email discussions. The fact that Lumicore had access to and reviewed OWS's published application materially undermines the narrative that Lumicore independently conceived the claimed invention in late 2016 and then independently developed it over the subsequent years.

Finally, the email chain does not reference any reduction to practice, prototype fabrication, simulation results, or experimental validation of any grating coupler design concept discussed therein. The emails are purely exploratory in nature.

4. Annotated Schematic Drawings (Undated, Claimed Q4 2016)

The fourth and final category of evidence consists of hand-drawn schematics of a grating structure with annotations. Lumicore's contentions assert that these drawings were "created in Q4 2016," but the drawings themselves are completely undated.

The evidentiary deficiencies of these drawings are extensive. No date appears anywhere on the drawings. No authorship attribution appears on the drawings — neither a signature, initials, printed name, nor any other indication of who created them. No file metadata exists to be analyzed, because the drawings are physical documents with no electronic provenance. Lumicore's contentions assert a creation date of Q4 2016, but they provide no verifiable basis for this assertion. The drawings could have been created at any time — before or after OWS's priority date — and there is no independent evidence to pin them to any particular date.

On the substance, the schematics depict a generic two-dimensional periodic structure with annotations indicating grating parameters. However, the structure shown is at a high level of generality and could represent any number of grating configurations for range optical applications. The schematics do not clearly correspond to the specific polarization-diverse grating coupler architecture of the '015 Patent claims. They do not depict a silicon photonic transceiver integration, do not show polarization-splitting functionality, and do not include any dimensional specifications or performance parameters that would correspond to the specific limitations of the asserted claims.

Without any corroboration of the creation date, authorship, or provenance, these undated drawings have virtually no evidentiary value for a prior-conception defense. They are, at best, generic technical sketches of indeterminate origin and vintage.

C. Credibility Assessment

Taking a holistic view of Lumicore's documentary evidence and the surrounding circumstances, the overall credibility of Lumicore's prior-conception defense is poor. The defense suffers from multiple compounding credibility problems:

Self-serving evidence. All four categories of identified documents are internal Lumicore records that were created or maintained by current Lumicore employees who are parties to this litigation. Dr. Dalmqvist, the purported author of the notebook entries, is Lumicore's Vice President of Product Development and has direct oversight responsibility for the accused products. Dr. Michaud, a participant in the email chain, is now Lumicore's CTO. No independent third-party witness has been identified who can corroborate the dating, authenticity, or content of any of these documents. The absence of any third-party corroboration is a significant evidentiary gap that Lumicore is unlikely to be able to fill.

Metadata inconsistencies. The Northgate Services Inc. presentation's "last modified" date of March 2019 raises a strong inference of post-priority-date alteration. This is not a minor technical discrepancy; it is a two-year gap between the claimed creation date and the demonstrated last modification date, with the latter post-dating OWS's priority date. The undated schematics have no verifiable timestamp at all. These metadata issues are not merely technical quibbles — they go to the fundamental question of whether the documents existed in their current form before the priority date, which is the entire basis of the prior-conception defense.

Lack of specificity. Even taking the documents at face value and assuming arguendo that they were created when Lumicore claims, the documents do not disclose the specific claimed inventions with sufficient detail to constitute conception. They reflect general interest in polarization-diverse coupler concepts and, at most, preliminary exploration of two-dimensional grating approaches. They do not describe a definite and permanent idea of the complete and operative invention as required for conception. The December 2016 emails are the most telling in this regard: the phrase "exploring 2D grating concepts" is a statement of aspiration, not a disclosure of a completed inventive concept.

No reduction to practice. Lumicore's contentions vaguely reference R&D milestone reports from 2017 and 2018 as evidence of diligence toward reduction to practice. However, these reports have not been produced in full in discovery. What has been produced relates to general transceiver development at Lumicore during those years, not specifically to the grating coupler architecture at issue. The milestone reports reference product development goals for Lumicore's transceiver product line as a whole and do not document any specific prototyping, simulation, fabrication, or testing of a polarization-diverse grating coupler consistent with the '015 Patent claims.

Inconsistency with Lumicore's product timeline. The timeline of Lumicore's commercial products undermines the prior-conception narrative in a fundamental way. Lumicore's LumiLink 400G-ZR+ transceiver, launched in Q3 2022, does not practice the '015 Patent claims because it employs a conventional one-dimensional grating coupler without polarization-diverse functionality. Only the LumiLink 800G-DR8 (launched Q1 2023) and the LumiEdge 1600G-LR (launched Q4 2023) incorporate the accused polarization-diverse grating coupler architecture. If Lumicore had truly conceived the claimed invention by early 2017, the five-plus-year gap before implementing it in any commercial product is unexplained and inconsistent with Lumicore's purported "reasonable diligence" toward reduction to practice. During this multi-year gap, Lumicore launched the 400G-ZR+ with a different, non-infringing coupler architecture — a fact that suggests Lumicore did not possess the claimed polarization-diverse grating coupler technology until significantly later, likely after reviewing OWS's published patent application.

Michaud deposition admissions. Dr. Michaud's admission during her November 19, 2024 deposition that the Lumicore engineering team reviewed OWS's published patent application No. 2018/0123456 during the LumiLink design phase in 2021–2022 supports an inference of copying rather than independent prior conception. This admission, combined with the anticipated testimony of Melissa Chen — a former Lumicore engineer who is now employed at Veridian Photonics, Inc. and who is expected to provide testimony regarding OWS patent awareness within Lumicore's engineering team — significantly weakens the narrative that Lumicore independently conceived the claimed invention before OWS's priority date. The more plausible inference from the totality of the evidence is that Lumicore's engineering team became aware of OWS's technology through OWS's published applications and subsequently developed the accused products with knowledge of OWS's innovations.

Additionally, the testimony of Raymond Bautista, Lumicore's 30(b)(6) designee on Topic 14 (non-infringing alternatives), further undermines the prior-conception narrative. At his December 3, 2024 deposition, Mr. Bautista confirmed that Lumicore did not conduct any formal design-around analysis prior to the launch of the LumiEdge 1600G-LR. The absence of a design-around effort is inconsistent with the claim that Lumicore independently conceived the same technology years earlier; a company that independently developed the technology would have had no reason to consider a design-around, yet it also would have been expected to have documentation of a complete and well-understood internal development lineage — documentation that is conspicuously absent here.

D. Summary of Prior-Conception Defense Assessment

Risk Level: Low.

Lumicore's prior-conception defense faces fatal obstacles at both the legal and factual levels. At the legal level, the defense lacks a coherent statutory basis under the AIA first-inventor-to-file framework, because unpublished internal documents are not prior art under § 102(a)(1) or (a)(2), and Lumicore has not raised a derivation theory or demonstrated the elements required for the prior commercial use defense under § 273. At the factual level, the documentary evidence is insufficient to establish conception of the specific claimed invention prior to OWS's April 7, 2017 priority date, due to the lack of corroboration, the metadata inconsistencies, the lack of specificity, and the absence of reduction to practice.

The metadata inconsistencies — particularly the Northgate Services Inc. "last modified" date of March 2019 — create an affirmative basis for challenging the authenticity and dating of key documents and for arguing that the documents as they exist today do not accurately reflect their state as of the claimed creation dates.

Recommendation: This defense is a strong candidate for partial summary judgment. We recommend that OWS move for judgment as a matter of law that the '015 Patent is not invalid based on Lumicore's prior-conception defense, arguing that: (1) Lumicore's internal documents are not cognizable prior art under the AIA; (2) even under a prior-conception framework, the documents are uncorroborated as a matter of law; (3) the metadata inconsistencies and other credibility deficiencies preclude Lumicore from satisfying the clear-and-convincing-evidence standard; and (4) even taken at face value, the documents do not disclose all limitations of any asserted claim.

This recommendation is addressed in greater detail in Section VIII.A (Strategic Recommendations — Summary Judgment) below and will be further developed in the Draft Motion for Partial Summary Judgment — Validity of '015 Patent, anticipated for filing September 15, 2025.

discovery follow-up: Before the May 1, 2025 fact discovery close, we recommend pursuing the following discovery actions:

• Depose Dr. Eric Dalmqvist regarding the notebook entries, including authorship, dating methodology, chain of custody, storage history, whether any pages were added or removed, and his awareness of OWS patents.

• Issue a forensic examination request or third-party subpoena for Lumicore's IT department to produce native email server logs, document management system records, and backup tape data corroborating the claimed creation dates of the internal documents.

• Depose Melissa Chen (subpoena issued January 22, 2025, to Veridian Photonics, Inc.) regarding her knowledge of Lumicore's grating coupler development timeline and the extent of OWS patent awareness within Lumicore's engineering team during her tenure.

• Cross-reference Lumicore's 30(b)(6) designee testimony on Topic 14 (non-infringing alternatives). Raymond Bautista's December 3, 2024 deposition confirmation that Lumicore conducted no formal design-around analysis prior to the LumiEdge 1600G-LR launch further undermines the prior-conception narrative and should be preserved for use in summary judgment briefing and at trial.

V. ANALYSIS OF OBVIOUSNESS CONTENTIONS (35 U.S.C. § 103)

A. Bergmann (U.S. Patent No. 8,412,007) Combined with Simonsen (PCT/EP2015/071234)

1. Summary of References

Bergmann (U.S. Patent No. 8,412,007). Issued April 2, 2013, the Bergmann patent is directed to grating coupler structures for optical interconnects. Bergmann discloses a one-dimensional grating coupler designed to optimize coupling efficiency between an optical fiber and a silicon waveguide on a photonic integrated circuit. The patent teaches specific design techniques for the grating period, etch depth, and fill factor to maximize coupling efficiency for a single polarization state (TE mode). Bergmann also teaches apodization of the grating structure to improve the mode-field matching between the fiber mode and the waveguide mode. However, Bergmann is fundamentally limited to one-dimensional grating structures and does not address polarization diversity. The coupler disclosed in Bergmann is inherently polarization-dependent and can only efficiently couple light in a single polarization state. Bergmann does not teach, suggest, or disclose a two-dimensional sub-wavelength grating structure of any kind.

Simonsen (PCT/EP2015/071234). Published September 17, 2015, the Simonsen PCT application is directed to an optical coupling arrangement incorporating polarization management. Simonsen teaches the use of discrete polarization-splitting elements — specifically, polarizing beam splitters and waveplates — to manage the polarization state of light coupled between an optical fiber and a photonic chip. However, Simonsen's optical coupling arrangement operates in the context of a free-space optical system, not a silicon photonic transceiver with monolithically integrated grating couplers. The polarization management approach described by Simonsen relies on external, bulk-optics components positioned in the free-space optical path between the fiber and the chip. This is a fundamentally different architecture from the '015 Patent's approach, which achieves polarization diversity through the design of the grating coupler itself — specifically, through a two-dimensional sub-wavelength grating that inherently couples both TE and TM polarization modes without the need for separate external polarization-splitting components.

2. Examiner's Prior Consideration

This exact combination of Bergmann and Simonsen was raised by the USPTO examiner during prosecution of the '015 Patent. The examiner issued a rejection under 35 U.S.C. § 103, asserting that the combination of Bergmann's grating coupler structure with Simonsen's polarization management teaching would have rendered the claimed polarization-diverse grating coupler obvious to a person of ordinary skill in the art.

In response, the applicants — represented by Dr. Martin Chu of Cascade IP Advisors — overcame the rejection through a combination of claim amendment and argument. Specifically, the applicants amended Claim 12 to specify particular structural characteristics of the "two-dimensional sub-wavelength grating" that were not disclosed or suggested by either Bergmann or Simonsen. The applicants further argued that a person of ordinary skill in the art would not have been motivated to combine these references, because they address fundamentally different coupling architectures: Bergmann addresses one-dimensional grating couplers for single-polarization coupling, while Simonsen addresses free-space polarization management using bulk-optics components. The applicants explained that the technological barrier to integrating polarization-diverse functionality into a sub-wavelength grating on a silicon substrate — rather than using external discrete components — was a significant one that the prior art did not teach or suggest how to overcome. The applicants supported these arguments with Declaration evidence addressing the state of the art and the level of ordinary skill.

The examiner was persuaded by the applicants' response and issued a Notice of Allowance. The claims were allowed without further rejection.

3. Analysis. Lumicore's obviousness contentions based on the Bergmann-Simonsen combination essentially ask the Court and, ultimately, the jury to second-guess the examiner's decision to allow the claims after considering this very combination. While it is well-established that an examiner's decision during prosecution is not preclusive and that invalidity may be proven at trial even for prior art that was before the examiner, see KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398, 426 (2007), the practical significance of the examiner's prior consideration is substantial.

The presumption of validity under 35 U.S.C. § 282 applies to every issued patent, and the burden of proving invalidity by clear and convincing evidence rests on the party asserting it. Kestrel Partners LLC v. i4i Ltd. Partnership, 564 U.S. 91, 95-97 (2011). When the prior art at issue was considered by the examiner during prosecution, the presumption of validity carries enhanced weight. See Am. Hoist & Derrick Co. v. Sowa & Sons, Inc., 725 F.2d 1350, 1359 (Fed. Cir. 1984) (noting that "when the prior art was before the examiner during prosecution . . . the challenger's burden is especially difficult"). The Federal Circuit has consistently held that an invalidity challenge based on art that the examiner considered and rejected faces a particularly high evidentiary hurdle. Lumicore will need to present significantly different analysis, arguments, or evidence than what the examiner considered in order to meet this burden.

Beyond the procedural significance of the examiner's prior consideration, the substantive merits of the Bergmann-Simonsen combination are deficient for the following reasons:

Missing claim limitations. Claims 1 and 12, the two independent claims, require a "polarization-diverse grating coupler" that is "capable of coupling light of two orthogonal polarization states." Berg

MEMORANDUM
PRIVILEGED AND CONFIDENTIAL — ATTORNEY WORK PRODUCT
To: Alan Ngo, Responsible Partner; Marcus Delgado, Billing Partner
From: Omar Siddiqui, Working Associate; Wendy Schultz, Lead Associate
Date: November 7, 2024
Re: Analysis of Lumicore Technologies, Inc.'s Invalidity Contentions for U.S. Patent No. 11,402,015 ("'015 Patent") — Prior-Conception Defense and Other Invalidity Theories
Matter: Optiwave Semiconductor Corp. v. Lumicore Technologies, Inc., Case No. 2:24-cv-00319-JRG (E.D. Tex.)
Classification: Attorney-Client Privileged / Attorney Work Product — Do Not Distribute Outside Case Team
This memorandum is protected by the attorney-client privilege and the work-product doctrine. It has been prepared at the direction of counsel and reflects the mental impressions, conclusions, opinions, and legal theories of the attorneys involved. It is intended solely for the use of the individuals identified above and other members of the case team as authorized by the responsible partner. Any unauthorized disclosure may result in waiver of applicable privileges.
I. EXECUTIVE SUMMARY
The purpose of this memorandum is to evaluate Lumicore Technologies, Inc.'s ("Lumicore") invalidity contentions as set forth in its P.R. 3-3 Invalidity Contentions served on October 14, 2024, as they pertain specifically to U.S. Patent No. 11,402,015 (the "'015 Patent"), entitled "Polarization-Diverse Grating Coupler for Silicon Photonic Transceivers." This memorandum analyzes each invalidity theory asserted by Lumicore, evaluates the strength and weakness of the supporting evidence, and provides strategic recommendations for responding to these contentions through discovery, expert preparation, dispositive motions, and trial strategy.
Our key conclusion is as follows: Lumicore's primary invalidity theory for the '015 Patent is a prior-conception defense based on Lumicore's own internal design documents purportedly dated between late 2016 and early 2017. This defense is, in our assessment, the weakest of the invalidity theories asserted across all four asserted patents in this litigation. The defense suffers from several fundamental infirmities. First, the internal documents Lumicore relies upon lack adequate corroboration, as required by well-established Federal Circuit precedent governing prior-conception claims. Second, the documents present serious credibility issues regarding their dating and authorship, including a critical metadata inconsistency in which a Northgate Services Inc. presentation claimed to have been created in January 2017 reflects a "last modified" date of March 2019 — nearly two years after our client Optiwave Semiconductor Corp.'s ("OWS") April 7, 2017 provisional filing date. Third, the defense faces a threshold legal obstacle under the America Invents Act ("AIA") first-inventor-to-file framework, because unpublished internal documents do not constitute prior art under 35 U.S.C. § 102(a)(1) or (a)(2), and Lumicore has not raised a derivation proceeding or clearly articulated any other viable statutory basis for its theory. For these reasons, the prior-conception defense likely cannot survive summary judgment.
In addition to the prior-conception defense, Lumicore asserts obviousness under 35 U.S.C. § 103 by combining certain prior-art references, principally the Bergmann patent (U.S. Patent No. 8,412,007) and the Simonsen PCT application (PCT/EP2015/071234). These combination arguments are addressed in detail below and are found to present moderate but manageable risk. Notably, this exact Bergmann-Simonsen combination was considered by the USPTO examiner during prosecution of the '015 Patent and was overcome through a narrowing amendment and accompanying arguments. The fact that the examiner considered and ultimately rejected this combination before allowing the claims significantly strengthens the presumption of validity and increases the evidentiary burden Lumicore must satisfy.
Our overall risk assessment is that the '015 Patent presents a low risk of being found invalid. Among the four asserted patents in this litigation — the '847 Patent, the '193 Patent, the '562 Patent, and the '015 Patent — the '015 Patent has the strongest validity posture. This assessment is reinforced by the robust secondary considerations of non-obviousness that OWS can present, including substantial commercial success of products practicing the '015 Patent claims, evidence of copying by Lumicore, long-felt but unresolved need in the silicon photonics industry for efficient polarization-diverse coupling solutions, and the failure of other competitors to achieve comparable results prior to OWS's innovation.
This memorandum should be read in conjunction with the companion Invalidity Contentions Analysis memos prepared for the other three asserted patents: the '847 Patent (November 1, 2024), the '193 Patent (November 3, 2024), and the '562 Patent (November 5, 2024). This memorandum also cross-references the comprehensive Prosecution History Review — All Asserted Patents (September 2024), the PHE Analysis — '015 Patent (October 12, 2024), and the IPR Risk Assessment Memorandum (May 15, 2024), each of which addresses related issues relevant to the analysis herein.
II. BACKGROUND ON THE '015 PATENT
A. Patent Overview
U.S. Patent No. 11,402,015 is entitled "Polarization-Diverse Grating Coupler for Silicon Photonic Transceivers." The patent discloses and claims a grating coupler architecture designed to address one of the persistent challenges in silicon photonics: efficiently coupling light of both transverse electric ("TE") and transverse magnetic ("TM") polarization states into and out of silicon photonic waveguides. The claimed architecture employs a two-dimensional sub-wavelength grating structure that achieves polarization-diverse coupling without the need for a separate external polarization-splitting element, representing a significant advance over prior one-dimensional grating coupler designs that were inherently polarization-dependent.
The relevant bibliographic and prosecution data for the '015 Patent is as follows:
•  Patent Number: U.S. Patent No. 11,402,015
•  Title: "Polarization-Diverse Grating Coupler for Silicon Photonic Transceivers"
•  Filing Date: August 30, 2019
•  Issue Date: August 2, 2022
•  Current Assignee: Optiwave Semiconductor Corp.
•  Original Assignee: Optiwave Semiconductor Corp.
•  Named Inventors: Dr. Jian-Wei Huang (Chief Technology Officer, OWS) and Dr. Nikolai Petrov (Vice President of Engineering, Photonics Division, OWS)
•  Priority Claim: The '015 Patent claims the benefit of Provisional Application No. 62/499,117, filed April 7, 2017. This provisional application is shared with the '193 Patent (U.S. Patent No. 10,891,193).
•  Effective Priority Date: April 7, 2017, the filing date of the provisional application.
•  Patent Family: The '015 Patent and the '193 Patent both claim priority to Provisional Application No. 62/499,117. However, the two patents are not in a continuation relationship with one another; they were filed as separate non-provisional applications, each claiming independent priority to the same provisional. The '015 Patent is directed to the grating coupler architecture itself, while the '193 Patent is directed to the broader transceiver system incorporating that architecture.
•  Prosecution Firm: Cascade IP Advisors, LLC (Lead Prosecution Attorney: Dr. Martin Chu, Reg. No. 52,341, 1550 Crystal Drive, Suite 600, Arlington, VA 22202)
•  Maintenance Fees: All maintenance fees are current through the next due date.
The provisional application filed on April 7, 2017 disclosed the polarization-diverse grating coupler concept in substantial detail, including experimental results from prototype devices fabricated on OWS's silicon photonic platform. The provisional disclosed the two-dimensional sub-wavelength grating structure, polarization-splitting functionality, and coupling-efficiency measurements for both TE and TM modes. The non-provisional application filed on August 30, 2019 expanded upon the provisional disclosures with additional embodiments and refined claim language.
B. Asserted Claims
OWS asserts Claims 1, 5, 8, 12, and 16 of the '015 Patent against Lumicore in this litigation. These claims are briefly summarized as follows:
Claim 1 is an independent claim directed to a polarization-diverse grating coupler capable of coupling light of two orthogonal polarization states in a silicon photonic transceiver. Claim 1 recites the fundamental structural and functional elements of the coupler, including the grating structure formed on a silicon substrate, the coupling of both TE and TM polarization modes, and the integration of the coupler with a silicon photonic waveguide. This is the broadest of the asserted claims and establishes the foundational scope of the patented invention.
Claim 5 depends from Claim 1 and adds specific structural features related to the grating coupler geometry. In particular, Claim 5 recites dimensional parameters and periodic structural characteristics of the grating elements that contribute to the coupler's polarization-diverse functionality. These additional limitations narrow the claim scope by requiring particular physical configurations not generically required by Claim 1.
Claim 8 also depends from Claim 1 and specifies coupling-efficiency parameters. Claim 8 requires that the grating coupler achieve specified minimum coupling efficiencies for both TE and TM polarization modes, expressed as numerical thresholds. This performance-based limitation further narrows the claim scope and is relevant to the infringement analysis because it ties the claim to measurable performance metrics of the accused products.
Claim 12 is the second independent claim and is of particular significance in this litigation. Claim 12 recites a specific "two-dimensional sub-wavelength grating" limitation, specifying the structural characteristics of the grating in greater detail than Claim 1. Claim 12 is the claim for which OWS also asserts infringement under the doctrine of equivalents with respect to certain features of the LumiEdge 1600G-LR product. As discussed below, Claim 12 was the subject of a narrowing amendment during prosecution to distinguish over the Bergmann-Simonsen prior-art combination, which has prosecution history estoppel implications for the doctrine of equivalents assertion. These estoppel implications are analyzed in the separate PHE Analysis — '015 Patent memorandum dated October 12, 2024.
Claim 16 depends from Claim 12 and further specifies characteristics of the polarization-splitting element integrated within the two-dimensional sub-wavelength grating. Claim 16 imposes additional structural and functional constraints on the splitting element's geometry and its relationship to the grating's sub-wavelength features.
C. Accused Products
OWS accuses the following Lumicore products of infringing the asserted claims of the '015 Patent:
LumiLink 800G-DR8. This product was launched by Lumicore in Q1 2023 and is Lumicore's flagship 800-gigabit-per-second data-rate silicon photonic transceiver module designed for data center interconnect applications. According to Lumicore's public filings and financial disclosures, the LumiLink 800G-DR8 generated approximately $128.4 million in revenue during FY 2023. OWS accuses this product of infringing Claims 1, 5, 8, 12, and 16 of the '015 Patent based on the polarization-diverse grating coupler architecture incorporated in its silicon photonic engine. The Benchmark Semiconductor Analysis teardown report dated June 2023 confirmed the presence of a two-dimensional grating coupler structure consistent with the '015 Patent claims.
LumiEdge 1600G-LR. This product was launched by Lumicore in Q4 2023 and represents Lumicore's next-generation 1.6-terabit-per-second long-reach transceiver module. The LumiEdge 1600G-LR generated approximately $41.7 million in revenue during FY 2023 (reflecting only a partial year of sales following its Q4 launch). OWS accuses this product of infringing Claims 1, 5, 8, 12, and 16 of the '015 Patent. The Benchmark Semiconductor Analysis teardown report dated February 2024 identified a grating coupler architecture in the LumiEdge that shares key structural features with the LumiLink design but incorporates certain modifications. It is with respect to these modifications in the LumiEdge product that OWS additionally asserts infringement of Claim 12 under the doctrine of equivalents.
It is noteworthy that the LumiLink 400G-ZR+ — which is accused of infringing certain claims of the other asserted patents in this litigation — is not accused of infringing the '015 Patent. The 400G-ZR+ employs a different, conventional one-dimensional grating coupler design that does not meet the "polarization-diverse" limitations of the '015 Patent claims. This product-specific distinction is relevant to Lumicore's prior-conception defense, as discussed in Section IV.C below.
D. Prosecution History Summary Relevant to Invalidity
The prosecution history of the '015 Patent is directly relevant to the invalidity analysis, particularly with respect to Lumicore's obviousness contentions based on the Bergmann-Simonsen combination. The key events in the prosecution history are summarized as follows:
Provisional Application No. 62/499,117 was filed on April 7, 2017 by the named inventors, Dr. Jian-Wei Huang and Dr. Nikolai Petrov, through Cascade IP Advisors, LLC. The provisional disclosed the polarization-diverse grating coupler concept with accompanying experimental results, including fabrication data and coupling-efficiency measurements obtained from prototype devices. The provisional application establishes April 7, 2017 as the effective priority date for the '015 Patent claims.
The non-provisional application was filed on August 30, 2019, with an express priority claim to Provisional Application No. 62/499,117. The non-provisional expanded upon the provisional disclosures with additional embodiments and detailed claim language directed to the specific structural and functional features of the polarization-diverse grating coupler.
During prosecution, the USPTO examiner issued a rejection under 35 U.S.C. § 103, asserting that the claims were obvious in view of the combination of the Bergmann patent (U.S. Patent No. 8,412,007, issued April 2, 2013) and the Simonsen PCT application (PCT/EP2015/071234, published September 17, 2015). The examiner's rejection asserted that Bergmann's disclosure of a grating coupler structure, when combined with Simonsen's teaching of polarization management in optical coupling arrangements, rendered the claimed polarization-diverse grating coupler obvious to a person of ordinary skill in the art.
In response to the examiner's rejection, the applicants — represented by Dr. Martin Chu of Cascade IP Advisors — took a two-pronged approach. First, the applicants amended Claim 12 to narrow the "two-dimensional sub-wavelength grating" limitation by specifying particular structural characteristics that distinguished the claimed grating from both Bergmann's one-dimensional grating coupler and Simonsen's polarization management arrangement. Second, the applicants submitted detailed arguments and a Declaration explaining that neither Bergmann nor Simonsen, alone or in combination, disclosed or suggested a two-dimensional sub-wavelength grating integrated within a silicon photonic transceiver to achieve simultaneous coupling of orthogonal polarization states. The applicants argued that a person of ordinary skill in the art would not have been motivated to combine these references to arrive at the claimed invention, because the references addressed fundamentally different coupling architectures and the technological barriers to implementing polarization-diverse sub-wavelength gratings on silicon substrates were substantial.
The examiner was persuaded by the amendment and arguments, and the claims were allowed. The patent issued on August 2, 2022.
This prosecution history is significant for two reasons. First, the examiner's consideration and rejection of the Bergmann-Simonsen combination strengthens the presumption of validity under 35 U.S.C. § 282 with respect to any invalidity challenge based on that same combination. Second, the narrowing amendment to Claim 12 has implications for prosecution history estoppel under the doctrine of equivalents, which is addressed in the separate PHE Analysis — '015 Patent memorandum dated October 12, 2024. For purposes of this invalidity analysis, the key takeaway is that the Bergmann-Simonsen combination was squarely before the examiner and was found insufficient to render the claims unpatentable.
III. SUMMARY OF LUMICORE'S INVALIDITY CONTENTIONS FOR THE '015 PATENT
A. Overview of Theories Asserted
Lumicore's P.R. 3-3 Invalidity Contentions, served on October 14, 2024, assert invalidity of the '015 Patent on three separate grounds:
1.  Prior conception and reduction to practice by Lumicore (primary theory). Lumicore contends that the subject matter of the asserted claims of the '015 Patent was conceived by Lumicore engineers prior to OWS's April 7, 2017 provisional filing date. Lumicore identifies a collection of internal design documents purportedly dated between late 2016 and early 2017 as evidence of this prior conception. Lumicore further contends that it exercised reasonable diligence toward reducing its conception to practice, pointing to internal R&D milestone reports from 2017 and 2018.
2.  Obviousness under 35 U.S.C. § 103 — Bergmann combined with Simonsen. Lumicore contends that the asserted claims would have been obvious in view of the Bergmann patent (U.S. Patent No. 8,412,007) in combination with the Simonsen PCT application (PCT/EP2015/071234), and potentially in further combination with other references. This is the same combination that was considered and rejected by the examiner during prosecution.
3.  Obviousness under 35 U.S.C. § 103 — Academic publications combined with known design principles. Lumicore contends that certain academic publications on grating coupler design, when combined with known grating coupler design principles and the general state of the art, render the asserted claims obvious. The specific academic references are identified in Section V.B below.
Notably, Lumicore does not assert anticipation under 35 U.S.C. § 102 against the '015 Patent. This stands in contrast to Lumicore's approach to the '847 Patent and '562 Patent, where anticipation by specific prior-art references is a primary invalidity theory. The absence of an anticipation theory against the '015 Patent is itself indicative of the relative strength of this patent's validity position, as it suggests that Lumicore was unable to identify any single reference that discloses all limitations of any asserted claim.
The prior-conception defense is novel in the context of this litigation and raises unique evidentiary and legal issues that are distinct from the prior-art challenges asserted against the other three asserted patents. As discussed in detail in Section IV, this defense confronts significant obstacles under both the AIA statutory framework and the corroboration requirement established by Federal Circuit precedent.
B. Prior-Conception Defense — Lumicore's Identified Evidence
In its P.R. 3-3 contentions, Lumicore identifies the following four categories of internal documents as purported evidence of prior conception:
First, Lumicore identifies internal design notebook entries attributed to Dr. Eric Dalmqvist, Vice President of Product Development at Lumicore. These entries are purportedly dated from November 2016 through February 2017. The entries consist of handwritten notes and sketches reflecting design concepts for a polarization-diverse coupling structure. Lumicore contends that these entries document the conception of the claimed grating coupler architecture during this timeframe.
Second, Lumicore identifies an internal Northgate Services Inc. presentation titled "Next-Gen Grating Coupler Architecture," which Lumicore claims was created in January 2017. The presentation is attributed to Lumicore's photonics design group and consists of 22 slides marked "Lumicore Technologies — Confidential." Lumicore contends the presentation demonstrates that the photonics design group had developed the claimed coupler concept as of January 2017.
Third, Lumicore identifies an email chain among Lumicore engineering staff, including Dr. Sandra Michaud (who was a senior engineer at Lumicore at the time and is now Lumicore's Chief Technology Officer). The email chain is dated December 2016 and discusses polarization-diverse coupler concepts. Lumicore contends this email chain demonstrates that the relevant technical concepts were under active discussion within Lumicore's engineering team prior to OWS's priority date.
Fourth, Lumicore identifies annotated schematic drawings of a two-dimensional grating structure. These drawings are undated, but Lumicore claims they were created in Q4 2016. Lumicore contends the drawings depict a grating structure consistent with the claimed invention.
Lumicore's contentions assert that these documents, collectively, demonstrate conception of the subject matter of Claims 1, 5, 8, 12, and 16 of the '015 Patent prior to OWS's April 7, 2017 provisional filing date. Lumicore further contends that it exercised reasonable diligence toward reduction to practice, pointing to internal R&D milestone reports from 2017 and 2018 that purportedly document ongoing development of the grating coupler technology.
C. Obviousness Theories — Prior-Art References Cited Against the '015 Patent
Among the 23 total prior-art references cited by Lumicore across all four asserted patents, the following references are specifically cited in the invalidity contentions against the '015 Patent:
U.S. Patent No. 8,412,007 (Bergmann), issued April 2, 2013. The Bergmann patent is directed to grating coupler structures for optical interconnects. It discloses a one-dimensional grating coupler with efficiency optimization techniques, including specific grating period designs and apodization methods aimed at improving the coupling efficiency between an optical fiber and a planar waveguide. Importantly, Bergmann does not disclose polarization diversity — that is, Bergmann's grating coupler is designed to couple a single polarization state (TE mode) and does not address the challenge of simultaneously coupling both TE and TM polarization modes. Bergmann also does not disclose a two-dimensional sub-wavelength grating structure.
PCT/EP2015/071234 (Simonsen), published September 17, 2015. The Simonsen PCT application is directed to an optical coupling arrangement with polarization management capabilities. Simonsen teaches the use of polarization-splitting elements in fiber-to-chip coupling, but in the context of a free-space optical system rather than a silicon photonic transceiver with integrated grating couplers. The polarization management approach described by Simonsen employs discrete optical components (e.g., beam splitters and waveplates) that are fundamentally different from the monolithically integrated two-dimensional grating coupler architecture claimed in the '015 Patent.
Lumicore also cites additional academic references on grating coupler design, including conference papers and journal articles discussing two-dimensional gratings in various optics contexts. These references are discussed in Section V.B below. In general, these academic references establish that two-dimensional grating structures were known in the broader field of optics but do not teach the specific application of such structures to polarization-diverse coupling in silicon photonic transceivers as claimed in the '015 Patent.
It is significant that Lumicore's obviousness combinations largely track the same Bergmann-Simonsen combination that was considered and rejected by the USPTO examiner during prosecution. While Lumicore supplements this combination with additional academic references, the core theory remains substantially the same as the rejected theory. This overlap is highly relevant to the strength of the presumption of validity and the evidentiary burden Lumicore must carry at trial.
IV. ANALYSIS OF PRIOR-CONCEPTION DEFENSE
A. Legal Framework — Prior Conception and Reduction to Practice Under the AIA
The legal framework applicable to Lumicore's prior-conception defense requires careful analysis, because this defense raises a threshold statutory question under the AIA that Lumicore's contentions do not adequately address.
The '015 Patent has an effective filing date of August 30, 2019 (the non-provisional filing date) with a priority date of April 7, 2017 (the provisional filing date). Because the effective filing date of the '015 Patent is after March 16, 2013, the patent is subject to the AIA's first-inventor-to-file provisions, codified at 35 U.S.C. § 102(a) as amended by the AIA. Under the AIA framework, the prior-art provisions differ materially from the pre-AIA first-to-invent regime, and these differences have direct implications for the viability of Lumicore's prior-conception defense.
Under AIA § 102(a)(1), "[a] person shall be entitled to a patent unless . . . the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention." Under AIA § 102(a)(2), a U.S. patent or published application constitutes prior art as of its effective filing date. The critical phrase in § 102(a)(1) for present purposes is "otherwise available to the public." Under the AIA's legislative history and subsequent case law, § 102(a)(1) was intended to create a unitary standard requiring public availability. See H.R. Rep. No. 112-98, at 42-43 (2011) (explaining that the phrase "available to the public" was added to "set forth an overarching requirement" for prior art status).
Lumicore's internal documents — the design notebook entries, Northgate Services Inc. presentation, email chain, and annotated schematics — are by their nature unpublished, confidential corporate records that were never made available to the public. They were not patented, described in a printed publication, in public use, on sale, or otherwise available to the public at any time before the '015 Patent's effective priority date. Accordingly, they cannot constitute prior art under § 102(a)(1). They likewise cannot constitute prior art under § 102(a)(2), because they are not U.S. patents, published applications, or WIPO publications.
This presents a fundamental obstacle to Lumicore's prior-conception defense. Under the pre-AIA first-to-invent regime, a defendant could defeat a patent by establishing that it (or another party) had independently conceived and reduced to practice the claimed invention before the patentee's date of invention, thus establishing prior inventorship. See 35 U.S.C. § 102(g) (pre-AIA). Under that regime, unpublished internal documents could be relevant as evidence of prior inventorship. However, § 102(g) was eliminated by the AIA, and the first-inventor-to-file system replaced the first-to-invent system for all patents with effective filing dates on or after March 16, 2013.
Lumicore's characterization of its theory as a "prior-conception defense" thus appears to conflate pre-AIA and AIA concepts. Under the AIA, there is no statutory defense based on prior conception alone. The available theories under which Lumicore might attempt to utilize its internal documents are limited and problematic:
Derivation under 35 U.S.C. § 135. The AIA replaced the pre-AIA interference proceedings with a derivation proceeding, which allows a party to challenge a patent by showing that the named inventor derived the claimed invention from another inventor. However, a derivation proceeding must be filed within one year of the first publication of the challenged claim. See 35 U.S.C. § 135(a). More critically, Lumicore has not raised a derivation theory in this litigation, and a derivation proceeding is brought before the Patent Trial and Appeal Board, not in district court litigation. To the extent Lumicore might argue derivation as a defense, it would need to establish not only that it conceived the invention first, but that the OWS inventors derived the invention from Lumicore — a theory for which Lumicore's contentions offer no factual support whatsoever. There is no allegation that the OWS inventors had access to Lumicore's internal documents or that any information flowed from Lumicore to OWS.
Prior commercial use defense under 35 U.S.C. § 273. The AIA expanded the prior commercial use defense, which permits a party to assert as a defense that it commercially used the subject matter of a patent in the United States at least one year before the effective filing date of the patent or the date of disclosure to the public, whichever is earlier. However, § 273 is an infringement defense, not an invalidity defense. A successful assertion of the § 273 defense does not render the patent invalid; it merely entitles the defendant to continue its prior commercial use. Moreover, the § 273 defense requires actual commercial use — not merely conception or internal documentation — and Lumicore's contentions do not allege that any commercial product embodying the claimed invention was in use before the '015 Patent's priority date. As noted above, Lumicore's first accused product (the LumiLink 800G-DR8) was not launched until Q1 2023, more than five years after the priority date.
General invalidity under 35 U.S.C. § 102(a)(1). As discussed above, this theory fails because Lumicore's internal documents were not publicly available. If Lumicore contends that any aspect of the designs reflected in these documents was disclosed to third parties or otherwise made publicly available before the priority date, its contentions do not clearly identify any such public disclosure. The documents are uniformly described as internal and confidential.
In sum, Lumicore's legal theory for using unpublished internal documents as a basis for invalidity is, at best, strained under the AIA framework. The most viable statutory vehicle — the prior commercial use defense under § 273 — is an infringement defense rather than an invalidity defense, and it requires commercial use that Lumicore has not alleged. Lumicore's characterization of its theory as a "prior-conception defense" reflects a fundamental misapprehension of the AIA statutory scheme, or at least a failure to articulate a coherent legal theory within that scheme. This threshold deficiency is itself a basis for seeking summary judgment on this defense, and it should be raised at the earliest opportunity.
B. Corroboration Requirement
Even setting aside the threshold AIA statutory issue, Lumicore's prior-conception defense is subject to the well-established corroboration requirement. Under Federal Circuit precedent, a party asserting prior conception must provide evidence of conception that is corroborated by evidence independent of the alleged inventor's own testimony. See Mahurkar v. C.R. Bard, Inc., 79 F.3d 1572, 1577-78 (Fed. Cir. 1996); Price v. Symsek, 988 F.2d 1187, 1194 (Fed. Cir. 1993). The corroboration requirement is applied using a "rule of reason" analysis, under which all pertinent evidence is considered to determine whether the inventor's testimony is credible. See Reese v. Hurst, 661 F.2d 1222, 1225 (Fed. Cir. 1981). Physical evidence, such as contemporaneous documents with verifiable dates, laboratory records with corroborating witness signatures, and third-party testimony, provides the strongest form of corroboration. Self-serving testimony by interested witnesses, particularly current employees of a party asserting the defense, is entitled to diminished weight.
We analyze each category of Lumicore's identified documentary evidence below against the corroboration requirement.
1. Design Notebook Entries (Dr. Eric Dalmqvist, November 2016 – February 2017)
Lumicore produced copies of notebook pages attributed to Dr. Eric Dalmqvist, Lumicore's Vice President of Product Development, during discovery. These pages purportedly span from November 2016 through February 2017 and contain handwritten notes and sketches relating to polarization-diverse coupler design concepts.
Our review of the produced copies reveals several significant issues that undermine the corroborative value of these notebook entries:
First, the notebook pages are not from a bound, paginated laboratory notebook with sequential page numbering. Standard scientific and engineering practice — and standard corporate intellectual property policies — typically require that invention disclosures and design concepts be recorded in bound notebooks with pre-numbered pages to prevent insertion, removal, or rearrangement of pages. Instead, the pages produced by Lumicore appear to be loose-leaf pages that were inserted into a ring binder. This format makes it impossible to verify the sequence in which the pages were created and eliminates the integrity safeguard that bound notebooks provide.
Second, none of the notebook pages bears a countersigning witness signature or a witness attestation date. It is standard practice in the research and development context, particularly for companies engaged in technology development in patent-intensive fields, for notebook entries to be reviewed and countersigned by a second person — typically a colleague who did not participate in the inventive work — to provide independent verification of the date and content of the entry. The complete absence of any such countersignatures from any page in Dr. Dalmqvist's purported notebook is a glaring corroboration deficiency.
Third, Lumicore has produced no chain-of-custody documentation for the notebook. In response to OWS's document requests, which specifically sought chain-of-custody documentation, retention records, and storage history for all documents identified in Lumicore's invalidity contentions, Lumicore produced no responsive materials pertaining to the Dalmqvist notebook. This absence raises questions about when the notebook was compiled, whether pages were added or removed at any point, and whether the notebook was maintained in a manner consistent with the claimed dates.
Fourth, Dr. Dalmqvist's deposition has not yet been taken. His deposition is currently scheduled for Q1–Q2 2025, and his testimony regarding the dating, context, authorship, and chain of custody of these notebook entries will be critical to assessing their evidentiary value. At this stage, the notebook entries are entirely self-serving records of a current Lumicore employee who has a direct interest in the outcome of this litigation, and no independent corroboration of their dating or authenticity has been provided.
Fifth, we have not yet completed a forensic analysis of the electronic scans of the notebook pages that were produced in Lumicore's document production. We recommend engaging a forensic document examiner to analyze the ink composition, paper dating, and any other physical characteristics of the original notebook pages if this defense gains traction. Additionally, a comparison of the electronic scan metadata with the claimed creation dates may yield useful information.
The key vulnerability of the notebook entries is clear: without any corroborating witness testimony, countersigning attestation, chain-of-custody records, or forensic verification, the self-serving nature of these entries — created or maintained by a current Lumicore executive with direct responsibility for the accused products — significantly undermines their evidentiary weight. Under the corroboration requirement, these entries alone cannot satisfy Lumicore's burden.
2. Internal Northgate Services Inc. Presentation ("Next-Gen Grating Coupler Architecture," January 2017)
The second category of evidence is a 22-slide Northgate Services Inc. presentation marked "Lumicore Technologies — Confidential" and titled "Next-Gen Grating Coupler Architecture." Lumicore claims this presentation was created in January 2017 by Lumicore's photonics design group.
Our review of this document and its metadata reveals the following issues:
The most significant issue is a critical metadata inconsistency. The file metadata for the Northgate Services Inc. presentation shows a "last modified" date of March 2019. This date is nearly two years after OWS's April 7, 2017 provisional filing date, which serves as the priority date for the '015 Patent. The March 2019 "last modified" date raises a serious and substantiated question as to whether the document was altered, updated, or re-saved after the priority date. If the content of the presentation was modified in March 2019, then its evidentiary value as proof of what Lumicore conceived prior to the priority date is fatally compromised. The content of the presentation as it exists today may reflect post-priority-date revisions that incorporate knowledge of OWS's published patent application or other post-priority-date developments.
The file metadata does show a "created" date of January 12, 2017, which facially supports Lumicore's claimed creation date. However, the "created" date field in Ashbury Holdings Northgate Services Inc. metadata is readily manipulable and is not dispositive of the actual creation date. A file's "created" date can be changed by modifying the file's properties, by using the "Save As" function in a manner that resets certain metadata fields, or by other means. Moreover, the discrepancy between the "created" date (January 2017) and the "last modified" date (March 2019) itself demands explanation: if the file was truly created in January 2017 and never modified, the "last modified" date should reflect the same or a closely proximate date.
Additionally, the presentation lacks any internal distribution records. No email has been produced in which the Northgate Services Inc. file was attached or forwarded with a pre-priority-date timestamp. Without such contemporaneous distribution evidence, there is no independent verification that the presentation existed in its current form at any time before OWS's priority date.
On the substance, our content analysis of the 22 slides reveals that the presentation discusses general polarization-diversity concepts and surveys various grating coupler architectures at a high level. However, the specific two-dimensional sub-wavelength grating structure claimed in Claim 12 of the '015 Patent is not disclosed in the presentation. The coupler designs shown in the slides are conventional one-dimensional grating couplers with polarization-splitting elements positioned at the output, which represents a materially different architecture from the claimed invention. The '015 Patent's innovation lies in achieving polarization diversity within the grating coupler structure itself through a two-dimensional sub-wavelength design — not through separate downstream polarization-splitting elements. The presentation does not disclose this integrated approach.
Even if the Northgate Services Inc. presentation is accepted as authentic and pre-dating OWS's priority date — which the metadata inconsistency calls into serious doubt — the presentation does not disclose all limitations of any asserted claim. At most, it demonstrates that Lumicore was aware of and interested in the general concept of polarization-diverse coupling, which is not the same as conception of the specific invention claimed in the '015 Patent.
3. Email Chain (December 2016)
The third category of evidence is an email chain among Lumicore engineering staff, including Dr. Sandra Michaud (who was then a senior engineer at Lumicore and has since been promoted to Chief Technology Officer). The email chain is dated December 2016 and discusses polarization-diverse coupler concepts.
The email chain was produced from Lumicore's email archives, and the email metadata appears facially consistent with December 2016 dates. Of the four categories of Lumicore's documentary evidence, this is the only one with metadata that does not present an obvious inconsistency. However, the substance of the emails significantly limits their evidentiary value.
Our review reveals that the emails discuss polarization-diverse coupling in general terms, reflecting a high-level technical discussion among engineers about emerging trends and design possibilities in the field. One email references "exploring 2D grating concepts" in the context of identifying research areas for future investigation. However, the emails do not disclose any specific structure, dimensions, materials, design parameters, or implementation approach for a two-dimensional sub-wavelength grating coupler. They do not include any drawings, schematics, or simulation results. They do not describe a definite and permanent idea of a complete and operative invention. At most, the emails constitute evidence of interest in the general field — not evidence of conception of the specific invention claimed in the '015 Patent.
The legal standard for conception requires "the formation in the mind of the inventor of a definite and permanent idea of the complete and operative invention, as it is hereafter to be applied in practice." Hybritech Inc. v. Monoclonal Antibodies, Inc., 802 F.2d 1367, 1376 (Fed. Cir. 1986). A general interest in a technical field, or even a stated intention to explore a particular design approach, does not constitute conception under this standard. The December 2016 emails fall far short of demonstrating that any Lumicore engineer had formed a definite and permanent idea of the polarization-diverse grating coupler architecture claimed in the '015 Patent.
Furthermore, Dr. Michaud's testimony from her November 19, 2024 deposition is highly relevant to the evidentiary significance of this email chain. During her deposition, Dr. Michaud admitted that the Lumicore engineering team reviewed OWS's published patent application No. 2018/0123456 — which corresponds to the '193 Patent and shares the same provisional application as the '015 Patent — during the design phase of the LumiLink product line in 2021–2022. This admission supports an inference that Lumicore's later design work on the grating coupler architecture in its accused products was influenced by OWS's published disclosures rather than by these early December 2016 email discussions. The fact that Lumicore had access to and reviewed OWS's published application materially undermines the narrative that Lumicore independently conceived the claimed invention in late 2016 and then independently developed it over the subsequent years.
Finally, the email chain does not reference any reduction to practice, prototype fabrication, simulation results, or experimental validation of any grating coupler design concept discussed therein. The emails are purely exploratory in nature.
4. Annotated Schematic Drawings (Undated, Claimed Q4 2016)
The fourth and final category of evidence consists of hand-drawn schematics of a grating structure with annotations. Lumicore's contentions assert that these drawings were "created in Q4 2016," but the drawings themselves are completely undated.
The evidentiary deficiencies of these drawings are extensive. No date appears anywhere on the drawings. No authorship attribution appears on the drawings — neither a signature, initials, printed name, nor any other indication of who created them. No file metadata exists to be analyzed, because the drawings are physical documents with no electronic provenance. Lumicore's contentions assert a creation date of Q4 2016, but they provide no verifiable basis for this assertion. The drawings could have been created at any time — before or after OWS's priority date — and there is no independent evidence to pin them to any particular date.
On the substance, the schematics depict a generic two-dimensional periodic structure with annotations indicating grating parameters. However, the structure shown is at a high level of generality and could represent any number of grating configurations for range optical applications. The schematics do not clearly correspond to the specific polarization-diverse grating coupler architecture of the '015 Patent claims. They do not depict a silicon photonic transceiver integration, do not show polarization-splitting functionality, and do not include any dimensional specifications or performance parameters that would correspond to the specific limitations of the asserted claims.
Without any corroboration of the creation date, authorship, or provenance, these undated drawings have virtually no evidentiary value for a prior-conception defense. They are, at best, generic technical sketches of indeterminate origin and vintage.
C. Credibility Assessment
Taking a holistic view of Lumicore's documentary evidence and the surrounding circumstances, the overall credibility of Lumicore's prior-conception defense is poor. The defense suffers from multiple compounding credibility problems:
Self-serving evidence. All four categories of identified documents are internal Lumicore records that were created or maintained by current Lumicore employees who are parties to this litigation. Dr. Dalmqvist, the purported author of the notebook entries, is Lumicore's Vice President of Product Development and has direct oversight responsibility for the accused products. Dr. Michaud, a participant in the email chain, is now Lumicore's CTO. No independent third-party witness has been identified who can corroborate the dating, authenticity, or content of any of these documents. The absence of any third-party corroboration is a significant evidentiary gap that Lumicore is unlikely to be able to fill.
Metadata inconsistencies. The Northgate Services Inc. presentation's "last modified" date of March 2019 raises a strong inference of post-priority-date alteration. This is not a minor technical discrepancy; it is a two-year gap between the claimed creation date and the demonstrated last modification date, with the latter post-dating OWS's priority date. The undated schematics have no verifiable timestamp at all. These metadata issues are not merely technical quibbles — they go to the fundamental question of whether the documents existed in their current form before the priority date, which is the entire basis of the prior-conception defense.
Lack of specificity. Even taking the documents at face value and assuming arguendo that they were created when Lumicore claims, the documents do not disclose the specific claimed inventions with sufficient detail to constitute conception. They reflect general interest in polarization-diverse coupler concepts and, at most, preliminary exploration of two-dimensional grating approaches. They do not describe a definite and permanent idea of the complete and operative invention as required for conception. The December 2016 emails are the most telling in this regard: the phrase "exploring 2D grating concepts" is a statement of aspiration, not a disclosure of a completed inventive concept.
No reduction to practice. Lumicore's contentions vaguely reference R&D milestone reports from 2017 and 2018 as evidence of diligence toward reduction to practice. However, these reports have not been produced in full in discovery. What has been produced relates to general transceiver development at Lumicore during those years, not specifically to the grating coupler architecture at issue. The milestone reports reference product development goals for Lumicore's transceiver product line as a whole and do not document any specific prototyping, simulation, fabrication, or testing of a polarization-diverse grating coupler consistent with the '015 Patent claims.
Inconsistency with Lumicore's product timeline. The timeline of Lumicore's commercial products undermines the prior-conception narrative in a fundamental way. Lumicore's LumiLink 400G-ZR+ transceiver, launched in Q3 2022, does not practice the '015 Patent claims because it employs a conventional one-dimensional grating coupler without polarization-diverse functionality. Only the LumiLink 800G-DR8 (launched Q1 2023) and the LumiEdge 1600G-LR (launched Q4 2023) incorporate the accused polarization-diverse grating coupler architecture. If Lumicore had truly conceived the claimed invention by early 2017, the five-plus-year gap before implementing it in any commercial product is unexplained and inconsistent with Lumicore's purported "reasonable diligence" toward reduction to practice. During this multi-year gap, Lumicore launched the 400G-ZR+ with a different, non-infringing coupler architecture — a fact that suggests Lumicore did not possess the claimed polarization-diverse grating coupler technology until significantly later, likely after reviewing OWS's published patent application.
Michaud deposition admissions. Dr. Michaud's admission during her November 19, 2024 deposition that the Lumicore engineering team reviewed OWS's published patent application No. 2018/0123456 during the LumiLink design phase in 2021–2022 supports an inference of copying rather than independent prior conception. This admission, combined with the anticipated testimony of Melissa Chen — a former Lumicore engineer who is now employed at Veridian Photonics, Inc. and who is expected to provide testimony regarding OWS patent awareness within Lumicore's engineering team — significantly weakens the narrative that Lumicore independently conceived the claimed invention before OWS's priority date. The more plausible inference from the totality of the evidence is that Lumicore's engineering team became aware of OWS's technology through OWS's published applications and subsequently developed the accused products with knowledge of OWS's innovations.
Additionally, the testimony of Raymond Bautista, Lumicore's 30(b)(6) designee on Topic 14 (non-infringing alternatives), further undermines the prior-conception narrative. At his December 3, 2024 deposition, Mr. Bautista confirmed that Lumicore did not conduct any formal design-around analysis prior to the launch of the LumiEdge 1600G-LR. The absence of a design-around effort is inconsistent with the claim that Lumicore independently conceived the same technology years earlier; a company that independently developed the technology would have had no reason to consider a design-around, yet it also would have been expected to have documentation of a complete and well-understood internal development lineage — documentation that is conspicuously absent here.
D. Summary of Prior-Conception Defense Assessment
Risk Level: Low.
Lumicore's prior-conception defense faces fatal obstacles at both the legal and factual levels. At the legal level, the defense lacks a coherent statutory basis under the AIA first-inventor-to-file framework, because unpublished internal documents are not prior art under § 102(a)(1) or (a)(2), and Lumicore has not raised a derivation theory or demonstrated the elements required for the prior commercial use defense under § 273. At the factual level, the documentary evidence is insufficient to establish conception of the specific claimed invention prior to OWS's April 7, 2017 priority date, due to the lack of corroboration, the metadata inconsistencies, the lack of specificity, and the absence of reduction to practice.
The metadata inconsistencies — particularly the Northgate Services Inc. "last modified" date of March 2019 — create an affirmative basis for challenging the authenticity and dating of key documents and for arguing that the documents as they exist today do not accurately reflect their state as of the claimed creation dates.
Recommendation: This defense is a strong candidate for partial summary judgment. We recommend that OWS move for judgment as a matter of law that the '015 Patent is not invalid based on Lumicore's prior-conception defense, arguing that: (1) Lumicore's internal documents are not cognizable prior art under the AIA; (2) even under a prior-conception framework, the documents are uncorroborated as a matter of law; (3) the metadata inconsistencies and other credibility deficiencies preclude Lumicore from satisfying the clear-and-convincing-evidence standard; and (4) even taken at face value, the documents do not disclose all limitations of any asserted claim.
This recommendation is addressed in greater detail in Section VIII.A (Strategic Recommendations — Summary Judgment) below and will be further developed in the Draft Motion for Partial Summary Judgment — Validity of '015 Patent, anticipated for filing September 15, 2025.
discovery follow-up: Before the May 1, 2025 fact discovery close, we recommend pursuing the following discovery actions:
•  Depose Dr. Eric Dalmqvist regarding the notebook entries, including authorship, dating methodology, chain of custody, storage history, whether any pages were added or removed, and his awareness of OWS patents.
•  Issue a forensic examination request or third-party subpoena for Lumicore's IT department to produce native email server logs, document management system records, and backup tape data corroborating the claimed creation dates of the internal documents.
•  Depose Melissa Chen (subpoena issued January 22, 2025, to Veridian Photonics, Inc.) regarding her knowledge of Lumicore's grating coupler development timeline and the extent of OWS patent awareness within Lumicore's engineering team during her tenure.
•  Cross-reference Lumicore's 30(b)(6) designee testimony on Topic 14 (non-infringing alternatives). Raymond Bautista's December 3, 2024 deposition confirmation that Lumicore conducted no formal design-around analysis prior to the LumiEdge 1600G-LR launch further undermines the prior-conception narrative and should be preserved for use in summary judgment briefing and at trial.
V. ANALYSIS OF OBVIOUSNESS CONTENTIONS (35 U.S.C. § 103)
A. Bergmann (U.S. Patent No. 8,412,007) Combined with Simonsen (PCT/EP2015/071234)
1. Summary of References
Bergmann (U.S. Patent No. 8,412,007). Issued April 2, 2013, the Bergmann patent is directed to grating coupler structures for optical interconnects. Bergmann discloses a one-dimensional grating coupler designed to optimize coupling efficiency between an optical fiber and a silicon waveguide on a photonic integrated circuit. The patent teaches specific design techniques for the grating period, etch depth, and fill factor to maximize coupling efficiency for a single polarization state (TE mode). Bergmann also teaches apodization of the grating structure to improve the mode-field matching between the fiber mode and the waveguide mode. However, Bergmann is fundamentally limited to one-dimensional grating structures and does not address polarization diversity. The coupler disclosed in Bergmann is inherently polarization-dependent and can only efficiently couple light in a single polarization state. Bergmann does not teach, suggest, or disclose a two-dimensional sub-wavelength grating structure of any kind.
Simonsen (PCT/EP2015/071234). Published September 17, 2015, the Simonsen PCT application is directed to an optical coupling arrangement incorporating polarization management. Simonsen teaches the use of discrete polarization-splitting elements — specifically, polarizing beam splitters and waveplates — to manage the polarization state of light coupled between an optical fiber and a photonic chip. However, Simonsen's optical coupling arrangement operates in the context of a free-space optical system, not a silicon photonic transceiver with monolithically integrated grating couplers. The polarization management approach described by Simonsen relies on external, bulk-optics components positioned in the free-space optical path between the fiber and the chip. This is a fundamentally different architecture from the '015 Patent's approach, which achieves polarization diversity through the design of the grating coupler itself — specifically, through a two-dimensional sub-wavelength grating that inherently couples both TE and TM polarization modes without the need for separate external polarization-splitting components.
2. Examiner's Prior Consideration
This exact combination of Bergmann and Simonsen was raised by the USPTO examiner during prosecution of the '015 Patent. The examiner issued a rejection under 35 U.S.C. § 103, asserting that the combination of Bergmann's grating coupler structure with Simonsen's polarization management teaching would have rendered the claimed polarization-diverse grating coupler obvious to a person of ordinary skill in the art.
In response, the applicants — represented by Dr. Martin Chu of Cascade IP Advisors — overcame the rejection through a combination of claim amendment and argument. Specifically, the applicants amended Claim 12 to specify particular structural characteristics of the "two-dimensional sub-wavelength grating" that were not disclosed or suggested by either Bergmann or Simonsen. The applicants further argued that a person of ordinary skill in the art would not have been motivated to combine these references, because they address fundamentally different coupling architectures: Bergmann addresses one-dimensional grating couplers for single-polarization coupling, while Simonsen addresses free-space polarization management using bulk-optics components. The applicants explained that the technological barrier to integrating polarization-diverse functionality into a sub-wavelength grating on a silicon substrate — rather than using external discrete components — was a significant one that the prior art did not teach or suggest how to overcome. The applicants supported these arguments with Declaration evidence addressing the state of the art and the level of ordinary skill.
The examiner was persuaded by the applicants' response and issued a Notice of Allowance. The claims were allowed without further rejection.
3. Analysis.  Lumicore's obviousness contentions based on the Bergmann-Simonsen combination essentially ask the Court and, ultimately, the jury to second-guess the examiner's decision to allow the claims after considering this very combination. While it is well-established that an examiner's decision during prosecution is not preclusive and that invalidity may be proven at trial even for prior art that was before the examiner, see KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398, 426 (2007), the practical significance of the examiner's prior consideration is substantial.
The presumption of validity under 35 U.S.C. § 282 applies to every issued patent, and the burden of proving invalidity by clear and convincing evidence rests on the party asserting it. Kestrel Partners LLC v. i4i Ltd. Partnership, 564 U.S. 91, 95-97 (2011). When the prior art at issue was considered by the examiner during prosecution, the presumption of validity carries enhanced weight. See Am. Hoist & Derrick Co. v. Sowa & Sons, Inc., 725 F.2d 1350, 1359 (Fed. Cir. 1984) (noting that "when the prior art was before the examiner during prosecution . . . the challenger's burden is especially difficult"). The Federal Circuit has consistently held that an invalidity challenge based on art that the examiner considered and rejected faces a particularly high evidentiary hurdle. Lumicore will need to present significantly different analysis, arguments, or evidence than what the examiner considered in order to meet this burden.
Beyond the procedural significance of the examiner's prior consideration, the substantive merits of the Bergmann-Simonsen combination are deficient for the following reasons:
Missing claim limitations. Claims 1 and 12, the two independent claims, require a "polarization-diverse grating coupler" that is "capable of coupling light of two orthogonal polarization states." Berg

MEMORANDUM

I. EXECUTIVE SUMMARY

II. BACKGROUND ON THE '015 PATENT

III. SUMMARY OF LUMICORE'S INVALIDITY CONTENTIONS FOR THE '015 PATENT

IV. ANALYSIS OF PRIOR-CONCEPTION DEFENSE

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