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UNITED STATES DISTRICT COURT EASTERN DISTRICT OF TEXAS MARSHALL DIVISION
OPTIWAVE SEMICONDUCTOR CORP.,
Plaintiff,
v.
LUMICORE TECHNOLOGIES, INC.,
Defendant.
Civil Action No. 2:24-cv-00319-JRG
The Honorable James R. Gilstrap
JURY TRIAL DEMANDED
PLAINTIFF OPTIWAVE SEMICONDUCTOR CORP.'S OPPOSITION TO DEFENDANT LUMICORE TECHNOLOGIES, INC.'S MOTION FOR SUMMARY JUDGMENT OF NO INFRINGEMENT UNDER THE DOCTRINE OF EQUIVALENTS
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I. INTRODUCTION
Plaintiff Optiwave Semiconductor Corp. ("OWS") respectfully submits this Opposition to Defendant Lumicore Technologies, Inc.'s ("Lumicore") Motion for Summary Judgment seeking to preclude OWS's doctrine of equivalents ("DOE") contentions as to Claims 3 and 7 of U.S. Patent No. 10,891,193 (the "'193 Patent") and Claim 12 of U.S. Patent No. 11,402,015 (the "'015 Patent"). For the reasons set forth below, the motion should be denied in its entirety.
Lumicore's motion is built upon a fundamentally flawed premise: that the narrowing amendments made during prosecution of the '193 Patent and the '015 Patent operate as an absolute bar to OWS's infringement contentions under the doctrine of equivalents. Lumicore invokes the presumption of prosecution history estoppel articulated in Festo Corp. v. Fenmore & Co., 535 U.S. 722 (2002), and contends that OWS cannot, as a matter of law, assert equivalents for the "coherent detection module" limitation in the '193 Patent or the "two-dimensional sub-wavelength grating" limitation in the '015 Patent. That argument fails for multiple, independent reasons.
First, even assuming the Festo presumption of surrender applies — which OWS does not concede in its entirety — the presumption is overcome because the narrowing amendments at issue bear only a tangential relation to the equivalents asserted against Lumicore's accused products: the LumiLink 400G-ZR+, the LumiLink 800G-DR8, and the LumiEdge 1600G-LR. The amendment to the '193 Patent was made to distinguish a prior-art reference disclosing a fundamentally different detection paradigm — direct (non-coherent) detection — and did not foreclose alternative coherent-detection topologies. The amendment to the '015 Patent was made to overcome an obviousness combination involving a one-dimensional grating coupler and a non-polarization-diverse design, and did not foreclose two-dimensional sub-wavelength gratings with alternative fill-factor ratios that nonetheless achieve polarization-diverse coupling. In both instances, the rationale underlying the narrowing amendment is peripheral to, and not directly relevant to, the equivalents OWS asserts against Lumicore's products.
Second, the record evidence creates genuine disputes of material fact on every element of OWS's DOE contentions. Expert testimony from Dr. Caroline Ashford — Professor of Electrical Engineering and Photonics at the Northfield Institute of Technology and a nationally recognized authority on silicon-photonic integrated circuits — confirms that Lumicore's accused elements perform substantially the same function, in substantially the same way, to achieve substantially the same result as the corresponding claim limitations. Dr. Ashford's opinions are corroborated by physical teardown evidence from Benchmark Semiconductor Analysis, LLC, whose detailed reverse-engineering analyses of the accused products reveal structural and functional parallels to the patented designs. Lumicore's own internal design documents, produced in discovery under the Protective Order, describe its grating coupler as achieving "polarization-diverse coupling equivalent to state-of-the-art designs." And the deposition testimony of Lumicore's own Chief Technology Officer, Dr. Sandra Michaud, confirms that Lumicore's design team reviewed OWS's published patent application during the design of the LumiLink 400G-ZR+ — powerful evidence that Lumicore understood the functional equivalence of its approach.
Third, summary judgment is simply the wrong procedural vehicle to resolve the inherently fact-intensive questions presented by the doctrine of equivalents. The Supreme Court has recognized that the equivalence determination is "quintessentially" a question of fact for the jury. Warner-Jenkinson Co. v. Harborline Enterprises Davis Chem. Co., 520 U.S. 17, 38 (1997). Whether the Festo tangential-relation exception applies is likewise a factual inquiry. Insituform Techs., Inc. v. CAT Contr., Inc., 385 F.3d 1360, 1370–71 (Fed. Cir. 2004). Here, both sides have retained highly qualified technical experts who offer competing opinions on these very questions. These competing opinions — and the voluminous documentary and testimonial evidence supporting OWS's position — create genuine disputes of material fact that preclude summary judgment.
The Court should deny Lumicore's motion and allow OWS's doctrine of equivalents contentions to proceed to the jury at the February 2, 2026 trial.
II. STATEMENT OF THE CASE
A. The Parties
Plaintiff Optiwave Semiconductor Corp. OWS is a Delaware corporation headquartered at 4810 Bayside Technology Parkway, Suite 300, Santa Clara, California 95054. OWS is a fabless semiconductor company specializing in the design, development, and commercialization of silicon photonics chipsets for data-center interconnects and high-speed optical communication systems. OWS is the third-largest U.S. supplier of silicon-photonics transceiver modules for hyperscale data centers, a market segment that has experienced explosive growth as cloud-computing providers build out increasingly data-intensive infrastructure. OWS's key product families include the OWS-400ZR, OWS-800XR, and OWS-1600DR transceiver module families, which serve the 400-gigabit, 800-gigabit, and 1.6-terabit interconnect markets, respectively.
OWS maintains a robust intellectual-property portfolio comprising 142 issued U.S. patents and 58 pending U.S. patent applications, the product of more than a decade of sustained research and development investment. OWS reported fiscal year 2023 revenues of approximately $487.3 million, reflecting the strong market demand for its silicon-photonics products. OWS is majority-owned (approximately 55%) by Ridgeline Capital Partners, LP, a private-equity firm, with the remaining ownership held by a combination of management, early-stage investors, and employee equity plans.
Defendant Lumicore Technologies, Inc. Lumicore is a Delaware corporation headquartered at 9200 Spectrum Boulevard, Building C, Austin, Texas 78759. Lumicore is a relatively fast-growing entrant in the silicon-photonics transceiver market, targeting both hyperscale data-center and telecommunications applications. Lumicore completed its initial public offering on the Nasdaq stock exchange in March 2022 at an offering price of $24 per share. As of the filing of the Complaint in this action, Lumicore had a market capitalization of approximately $3.4 billion. Lumicore's estimated fiscal year 2023 revenue was approximately $312.6 million, a significant portion of which was attributable to the accused products that are the subject of this litigation.
B. The Asserted Patents and Accused Products
OWS has asserted four U.S. utility patents in this action: U.S. Patent No. 10,234,847 (the "'847 Patent"); U.S. Patent No. 10,891,193 (the "'193 Patent"); U.S. Patent No. 9,678,562 (the "'562 Patent"); and U.S. Patent No. 11,402,015 (the "'015 Patent"). The doctrine of equivalents contentions at issue in Lumicore's anticipated motion involve only the '193 Patent and the '015 Patent.
The '193 Patent. United States Patent No. 10,891,193, entitled "High-Bandwidth Coherent Optical Transceiver Integrated on Silicon Substrate," was filed on April 7, 2017 and issued on January 12, 2021. The '193 Patent was originally assigned to OWS and claims priority to Provisional Application No. 62/499,117, filed April 7, 2017. The '193 Patent shares this common provisional application with the '015 Patent. The '193 Patent is directed to a coherent optical transceiver architecture integrated on a silicon substrate that achieves high-bandwidth data transmission suitable for data-center interconnect applications. The patent describes and claims, among other things, a "coherent detection module" that separates and processes in-phase and quadrature components of an incoming optical signal to recover amplitude and phase information with high fidelity. Claims 3 and 7 of the '193 Patent are at issue in OWS's DOE contentions.
The '015 Patent. United States Patent No. 11,402,015, entitled "Polarization-Diverse Grating Coupler for Silicon Photonic Transceivers," was filed on August 30, 2019 and issued on August 2, 2022. The '015 Patent was originally assigned to OWS. The '015 Patent is directed to a grating coupler structure for silicon photonic transceivers that efficiently couples light from an optical fiber into a silicon waveguide while managing both transverse electric ("TE") and transverse magnetic ("TM") polarization modes. The patent describes and claims, among other things, a "two-dimensional sub-wavelength grating" structure that creates polarization-diverse coupling using periodic nanostructures with feature dimensions below the operating wavelength. Claim 12 of the '015 Patent is at issue in OWS's DOE contentions.
The Accused Products. OWS accuses three Lumicore product families of infringement:
(1) LumiLink 400G-ZR+ — Lumicore's 400-gigabit coherent transceiver module, designed for data-center interconnect and metro-reach applications. The LumiLink 400G-ZR+ was launched commercially in the third quarter of 2022 and generated fiscal year 2023 revenue of approximately $94.8 million.
(2) LumiLink 800G-DR8 — Lumicore's 800-gigabit short-reach transceiver module, designed for intra-data-center connectivity. The LumiLink 800G-DR8 was launched commercially in the first quarter of 2023 and generated fiscal year 2023 revenue of approximately $128.4 million.
(3) LumiEdge 1600G-LR — Lumicore's 1.6-terabit long-reach transceiver module, designed for next-generation data-center and campus-network applications. The LumiEdge 1600G-LR was launched commercially in the fourth quarter of 2023 and generated fiscal year 2023 revenue of approximately $41.7 million.
The total accused-product revenue for fiscal year 2023 was approximately $264.9 million. OWS's damages analysis projects total accused-product revenue from product launch through the anticipated end of trial (Q3 2022 through Q4 2025) of approximately $714.6 million, a figure that continues to grow as Lumicore expands its market presence.
C. Procedural History Relevant to This Motion
OWS filed its Complaint on April 22, 2024 (D.E. 1), asserting seven counts including direct infringement (Counts I–IV), induced infringement (Count V), contributory infringement (Count VI), and willful infringement (Count VII). On September 16, 2024, OWS served its P.R. 3-1 Infringement Contentions (D.E. 32), which identified, among other things, doctrine of equivalents contentions for Claims 3 and 7 of the '193 Patent and Claim 12 of the '015 Patent. Those contentions specified the claim limitations at issue — the "coherent detection module" limitation in the '193 Patent and the "two-dimensional sub-wavelength grating" limitation in the '015 Patent — and provided detailed claim charts mapping the function, way, and result of each accused element to the corresponding claim limitation.
The parties filed their Joint Claim Construction Statement on October 28, 2024 (D.E. 40), identifying fourteen disputed claim terms across the four asserted patents. The parties thereafter briefed claim construction in a series of filings: OWS's Opening Claim Construction Brief (D.E. 44, filed November 15, 2024); Lumicore's Responsive Claim Construction Brief (D.E. 48, filed December 6, 2024); OWS's Reply (D.E. 52, filed December 20, 2024); and Lumicore's Sur-Reply (D.E. 56, filed January 10, 2025). The final Joint Claim Construction Chart was filed on January 15, 2025 (D.E. 58). A Markman hearing is currently scheduled for March 14, 2025.
Under the Court's Scheduling Order, fact discovery closes on May 1, 2025. Plaintiff's expert reports are due June 15, 2025. Defendant's rebuttal expert reports are due July 15, 2025. Expert discovery closes August 15, 2025. Dispositive motions are due September 15, 2025. Trial is set for February 2, 2026, with an estimated duration of seven to ten days.
D. The Specific Doctrine of Equivalents Contentions
OWS's DOE contentions, as set forth in its P.R. 3-1 Infringement Contentions and as supported by the expert analysis of Dr. Caroline Ashford, are as follows:
'193 Patent, Claims 3 and 7 — "Coherent Detection Module" Limitation. OWS contends that even if Lumicore's accused designs do not literally satisfy the "coherent detection module" limitation as the Court may construe that term, the accused element in each of the LumiLink 400G-ZR+, LumiLink 800G-DR8, and LumiEdge 1600G-LR products performs substantially the same function, in substantially the same way, to achieve substantially the same result as the claimed limitation. Specifically:
Function: The accused element performs substantially the same function as the claimed "coherent detection module" — namely, detecting coherent optical signals by separating and processing in-phase (I) and quadrature (Q) components of the received signal.
Way: The accused element operates in substantially the same way as the claimed "coherent detection module" — namely, using an integrated receiver front-end with phase-diverse detection on a silicon photonic substrate, wherein the incoming optical signal is mixed with a local oscillator reference and the resulting interference patterns are detected to extract the I and Q components.
Result: The accused element achieves substantially the same result as the claimed "coherent detection module" — namely, recovering the amplitude and phase information of the transmitted optical signal with high fidelity, thereby enabling high-bandwidth coherent optical communication.
'015 Patent, Claim 12 — "Two-Dimensional Sub-Wavelength Grating" Limitation. OWS contends that even if Lumicore's grating coupler implementation does not literally practice the "two-dimensional sub-wavelength grating" limitation as the Court may construe that term, the accused element in the LumiLink 800G-DR8 and LumiEdge 1600G-LR products performs substantially the same function, in substantially the same way, to achieve substantially the same result as the claimed limitation. Specifically:
Function: The accused element performs substantially the same function as the claimed "two-dimensional sub-wavelength grating" — namely, coupling light from an optical fiber into a silicon waveguide while managing both TE and TM polarization modes.
Way: The accused element operates in substantially the same way as the claimed "two-dimensional sub-wavelength grating" — namely, using a periodic nanostructure with feature dimensions below the operating wavelength to create polarization-diverse coupling through diffraction of the incoming light into guided modes within the silicon waveguide.
Result: The accused element achieves substantially the same result as the claimed "two-dimensional sub-wavelength grating" — namely, efficient, low-loss, polarization-insensitive fiber-to-chip optical coupling suitable for high-bandwidth transceiver applications.
III. LEGAL STANDARD
A. Summary Judgment Standard Under Rule 56
Summary judgment is appropriate only when "there is no genuine dispute as to any material fact and the movant is entitled to judgment as a matter of law." Fed. R. Civ. P. 56(a). A dispute of material fact is "genuine" if "the evidence is such that a reasonable jury could return a verdict for the nonmoving party." Anderson v. Liberty Lobby, Inc., 477 U.S. 242, 248 (1986). The substantive law governing the claims determines which facts are "material." Id. at 248.
In evaluating a motion for summary judgment, the court must construe all facts and draw all reasonable inferences in the light most favorable to the nonmoving party. Id. at 255; Matsushita Elec. Indus. Co. v. Zenith Radio Corp., 475 U.S. 574, 587 (1986). The court's role "is not to weigh the evidence and determine the truth of the matter but to determine whether there is a genuine issue for trial." Anderson, 477 U.S. at 249. "Credibility determinations, the weighing of the evidence, and the drawing of legitimate inferences from the facts are jury functions, not those of a judge." Id. at 255.
These principles carry particular force in patent infringement cases involving the doctrine of equivalents, where the Supreme Court has recognized that the equivalence determination is "quintessentially" a question of fact for the jury. Warner-Jenkinson Co. v. Harborline Enterprises Davis Chem. Co., 520 U.S. 17, 38 (1997). Accordingly, summary judgment on DOE questions is the exception, not the rule, and should be granted only when no reasonable jury could find infringement under the doctrine of equivalents. See Deere & Co. v. Bush Hog, LLC, 703 F.3d 1349, 1356 (Fed. Cir. 2012).
B. Doctrine of Equivalents — General Principles
Under the doctrine of equivalents, "a product or process that does not literally infringe upon the express terms of a patent claim may nonetheless be found to infringe if there is 'equivalence' between the elements of the accused product or process and the claimed elements of the patented invention." Warner-Jenkinson, 520 U.S. at 21. The doctrine exists to prevent a "fraud on a patent" — that is, to prevent a copyist from avoiding liability by making unimportant and insubstantial changes to the patented invention while retaining its essential character. Graver Tank & Mfg. Co. v. Linde Air Products Co., 339 U.S. 605, 607 (1950).
The principal test for equivalence is the "function-way-result" test, under which an accused element is equivalent to a claim limitation if it "performs substantially the same function in substantially the same way to obtain the same result." Id. at 608. This tripartite inquiry is applied on a limitation-by-limitation (element-by-element) basis, not to the invention as a whole. Warner-Jenkinson, 520 U.S. at 29. An equivalent must be assessed "in the context of the patent, the prior art, and the particular circumstances of the case." Graver Tank, 339 U.S. at 609. Because the analysis depends on the "particular circumstances" of each accused product and each claim limitation, it is inherently fact-intensive and generally unsuitable for summary resolution. Warner-Jenkinson, 520 U.S. at 38–40.
C. Prosecution History Estoppel — The *Festo* Framework
The doctrine of equivalents is subject to certain legal limitations, including prosecution history estoppel. When a patent applicant narrows the scope of a claim by amendment during prosecution for a "substantial reason related to patentability," the applicant is presumed to have surrendered the territory between the original claim scope and the amended claim scope. Festo Corp. v. Fenmore & Co., 535 U.S. 722, 740 (2002). This presumption of surrender applies when two conditions are met: (1) the patentee made a narrowing amendment to the relevant claim limitation, and (2) the amendment was adopted for a reason related to patentability, including to overcome prior-art rejections under 35 U.S.C. §§ 102 or 103, or to address issues of claim definiteness under 35 U.S.C. § 112. Id. at 736–37.
Critically, however, the Festo presumption is rebuttable. The Supreme Court expressly rejected the Federal Circuit's earlier "complete bar" approach, holding instead that the patentee may overcome the presumption by demonstrating that one of three exceptions applies:
(1) The Unforeseeability Exception. The alleged equivalent was not foreseeable at the time the narrowing amendment was made, and the patentee therefore could not have been expected to claim the equivalent. Festo, 535 U.S. at 740–41.
(2) The Tangential-Relation Exception. The rationale underlying the narrowing amendment bears only a tangential relation to the equivalent in question — that is, the reason for the amendment was "peripheral, or not directly relevant," to the accused equivalent. Id. at 740.
(3) The Catch-All Exception. There is some other reason suggesting that the patentee could not reasonably have been expected to have described the insubstantial substitute in question at the time of the amendment. Id. at 741.
The patentee bears the burden of establishing that one of these exceptions applies. Id. at 740–41. But that burden is a burden of production and persuasion to the factfinder, not a threshold showing that must be made to a court before the question can reach the jury. Where the evidence creates a genuine dispute as to whether an exception applies, summary judgment is inappropriate.
D. The Tangential-Relation Exception
Because OWS relies primarily on the tangential-relation exception, additional discussion of that exception is warranted.
The tangential-relation exception applies where "the reason for the amendment [is] merely tangential to the equivalent in question." Festo, 535 U.S. at 741. The Federal Circuit has explained that the inquiry focuses on whether the "narrowing amendment was peripheral, or not directly relevant, to the alleged equivalent." Honeywell Int'l, Inc. v. Hamilton Sundstrand Corp., 523 F.3d 1304, 1315 (Fed. Cir. 2008). The court examines the "objectively apparent reason for the narrowing amendment" and evaluates whether that reason is related to the equivalent at issue. Id. If the amendment was directed at a concern unrelated to — or only peripherally related to — the particular equivalent, the presumption of surrender is overcome. Id.
The tangential-relation inquiry is necessarily fact-intensive. As the Federal Circuit has recognized, the determination of whether the amendment rationale is tangential to the accused equivalent "requires an assessment of the relationship between the amendment and the equivalent," which involves examination of the prosecution history, the prior art, and the nature of the accused product. Insituform Techs., Inc. v. CAT Contr., Inc., 385 F.3d 1360, 1370–71 (Fed. Cir. 2004). Where the evidence regarding that relationship is disputed or susceptible to reasonable competing inferences, summary judgment is improper, and the question must be submitted to the factfinder. Id.
Importantly, the tangential-relation exception is not a narrow or rarely invoked doctrine. Rather, it reflects the Supreme Court's recognition that patent prosecution involves a complex and iterative process in which amendments may be made for range reasons, not all of which are directed at the precise variations that a subsequent infringer may adopt. See Festo, 535 U.S. at 741 (noting that "there are some cases . . . where the amendment cannot reasonably be viewed as surrendering a particular equivalent"). The exception ensures that prosecution history estoppel is applied with the precision demanded by principles of fundamental fairness, rather than as an overly blunt instrument that deprives the patentee of the protection to which it is entitled.
IV. ARGUMENT
A. Genuine Disputes of Material Fact Preclude Summary Judgment on OWS's Doctrine of Equivalents Contentions
Before addressing the specific contentions for each patent, OWS submits that the overarching question in this motion is whether the record evidence creates genuine disputes of material fact that preclude summary judgment. The answer is unequivocally yes.
The doctrine of equivalents analysis requires a factfinder to evaluate, for each claim limitation, whether the accused element performs substantially the same function, in substantially the same way, to achieve substantially the same result. Graver Tank, 339 U.S. at 608. Whether the Festo tangential-relation exception applies requires a further factual evaluation of the relationship between the narrowing amendment and the accused equivalent. Insituform, 385 F.3d at 1370–71. These are not questions of law that can be resolved by parsing the prosecution history in isolation. They require consideration of the full evidentiary record, including expert testimony, physical product analysis, design documents, and deposition testimony.
Here, the record evidence — which is already substantial and will continue to develop through the completion of expert discovery in August 2025 — creates genuine disputes on every relevant factual question. Dr. Ashford's expert analysis supports OWS's position on both the function-way-result inquiry and the tangential-relation exception. Benchmark Semiconductor Analysis's teardown reports provide physical evidence of the structural and functional similarities between the accused products and the patented designs. Lumicore's own internal documents and deposition testimony further support OWS's contentions. To the extent Lumicore offers competing expert opinions from Dr. Rajesh Sundaram, those opinions create a classic "battle of experts" that is the paradigmatic example of a factual dispute that must be resolved by the jury, not by the Court on a motion for summary judgment. See Conley v. Northgate Investors Inv. Advisory Corp., 1997 WL 61548, at 2 (N.D. Ill. Feb. 10, 1997) ("Summary judgment is particularly inappropriate where, as here, two experts disagree."); see also Northpoint Group Labs., Inc. v. 10X Genomics, Inc.*, 967 F.3d 1353, 1376 (Fed. Cir. 2020) (reversing summary judgment of no infringement under DOE where competing expert opinions created genuine disputes).
B. The '193 Patent: Prosecution History Estoppel Does Not Bar the Doctrine of Equivalents for Claims 3 and 7
1. Background on the Narrowing Amendment. During prosecution of the '193 Patent before the United States Patent and Trademark Office, the examiner issued a rejection of the original claims under 35 U.S.C. § 102 over a prior-art publication: Takahashi et al., "Dense WDM Silicon Photonic MUX," published in IEEE Photonics Technology Letters in March 2014 (hereinafter "Takahashi"). The Takahashi reference disclosed a wavelength-division multiplexing architecture for silicon photonics that employed a direct-detection (non-coherent) approach to optical signal detection. Takahashi's system relied on photodetection of intensity-modulated signals without reference to a local oscillator and without separation of in-phase and quadrature signal components.
In response to the examiner's § 102 rejection, Dr. Martin Chu of Cascade IP Advisors, LLC — the lead prosecution attorney responsible for the '193 Patent portfolio — filed an amendment narrowing the "coherent detection module" limitation. Specifically, the amendment added language requiring the coherent detection module to include a balanced-detector configuration having a particular structural and functional relationship to an on-chip local oscillator. This amendment was accompanied by remarks explaining that the amended claims distinguished over Takahashi because Takahashi disclosed only a direct-detection architecture and did not teach or suggest a coherent detection module with the balanced-detector/local-oscillator relationship recited in the amended claims. See Exhibit 1 (relevant excerpts from prosecution history of '193 Patent).
OWS does not dispute that this amendment constitutes a narrowing amendment made for reasons related to patentability — specifically, to overcome the examiner's § 102 rejection. Accordingly, OWS acknowledges that the Festo presumption of prosecution history estoppel applies as a threshold matter. But that is where Lumicore's argument ends and OWS's begins, because the presumption is rebuttable, and the record evidence demonstrates that the tangential-relation exception applies.
2. The Tangential-Relation Exception Applies. The central question is whether the rationale underlying the narrowing amendment — distinguishing over Takahashi's direct-detection multiplexer — bears only a tangential relation to the equivalent OWS asserts against Lumicore's accused products. The answer is clearly yes.
The Takahashi reference disclosed a fundamentally different detection paradigm. Takahashi's dense WDM silicon photonic multiplexer employed direct detection, a technique in which a photodetector simply measures the intensity of the incoming optical signal without reference to a local oscillator and without recovering phase information. Direct detection is a well-known, long-standing approach to optical signal detection that predates coherent detection by decades. It is fundamentally different from coherent detection in its operating principle, its signal-processing architecture, and its performance characteristics.
The amendment was directed at the direct-detection versus coherent-detection distinction. The prosecution remarks accompanying the amendment make clear that the applicant's purpose was to distinguish over Takahashi's direct-detection approach by adding specificity to the balanced-detector configuration and its relationship to the local oscillator — features that are hallmarks of coherent detection and that are entirely absent from direct-detection systems like Takahashi's. The amendment drew a line between coherent detection (which the claimed invention embodies) and non-coherent detection (which Takahashi taught). It did not draw a line between different implementations of coherent detection.
Lumicore's accused products employ a coherent-detection approach. The equivalents OWS asserts against Lumicore's accused products are squarely on the coherent-detection side of the line drawn by the amendment. Lumicore's accused products use integrated receiver front-ends that separate and process in-phase and quadrature components of the incoming optical signal by mixing the signal with a local oscillator reference — the very hallmarks of coherent detection. The only difference between Lumicore's implementation and the literal claim language is in the specific topology of the receiver front-end: Lumicore employs a modified 90° optical hybrid with integrated photodiodes in a different physical arrangement than the specific balanced-detector configuration recited in the amended claims. This is a variation within the coherent-detection paradigm, not a departure from it.
The relationship between the amendment rationale and the accused equivalent is tangential. Because the amendment was directed at excluding non-coherent (direct-detection) approaches — not at excluding alternative coherent-detection topologies — the rationale underlying the amendment is "peripheral, or not directly relevant, to the alleged equivalent." Honeywell, 523 F.3d at 1315. The accused equivalent (Lumicore's modified 90° hybrid topology) was not the subject of the prosecution exchange with the examiner. The examiner never raised Lumicore's topology or any analogous coherent-detection variant as prior art. The applicant's remarks were directed at a fundamentally different technological concern. Under these circumstances, the tangential-relation exception plainly applies.
Dr. Ashford's expert analysis confirms the tangential relationship. Dr. Caroline Ashford, in her supplemental declaration filed December 20, 2024 (D.E. 52-1), analyzed the prosecution history of the '193 Patent and opined that a person of ordinary skill in the art ("POSITA") — defined for purposes of the '193 Patent as a person having a Master of Science or Doctor of Philosophy degree in electrical engineering or photonics and at least three years of experience in silicon-photonic integrated circuit design — would understand that the narrowing amendment was directed at distinguishing non-coherent detection approaches and was not intended to foreclose all alternative coherent-detection module implementations. Dr. Ashford further opined that the specific balanced-detector configuration added by the amendment and the modified 90° hybrid topology used in Lumicore's products represent alternative implementations of the same fundamental coherent-detection concept, and that a POSITA would not have understood the amendment as surrendering equivalents encompassing Lumicore's approach. See Exhibit 6 (Declaration of Dr. Ashford).
3. The Function-Way-Result Analysis Creates a Triable Issue. Even apart from the prosecution history estoppel question, the underlying function-way-result analysis creates genuine disputes of material fact that preclude summary judgment.
Function. Both the claimed "coherent detection module" and the accused element in Lumicore's products perform substantially the same function: detecting coherent optical signals by separating and processing in-phase (I) and quadrature (Q) components of the incoming optical signal. This functional identity is not seriously disputed. Lumicore's own product literature describes the LumiLink 400G-ZR+ and LumiLink 800G-DR8 as "coherent transceivers" that perform "I/Q detection." The LumiEdge 1600G-LR likewise employs coherent detection for its long-reach functionality. Dr. Ashford opines that the function of the accused element is identical to the function of the claimed limitation. See Exhibit 6 ¶¶ 47–53.
Way. Both the claimed "coherent detection module" and the accused element operate in substantially the same way: using an integrated receiver front-end with phase-diverse detection on a silicon substrate, wherein the incoming optical signal is combined with a local oscillator reference to produce interference patterns from which the I and Q components are extracted. The difference between the accused implementation and the literal claim language lies in the specific physical topology of the optical hybrid and photodiode arrangement — Lumicore uses a modified 90° hybrid with integrated photodiodes in a different spatial configuration than the balanced-detector arrangement recited in the claims. Dr. Ashford opines that this difference is insubstantial because it does not alter the fundamental manner of operation: both approaches split the incoming signal, mix the split components with the local oscillator at different phase offsets, and detect the resulting interference to extract I and Q data. See Exhibit 6 ¶¶ 54–65. Dr. Ashford further explains that modified 90° hybrid topologies and balanced-detector configurations are recognized in the art as alternative implementations of the same underlying coherent-detection principle, differing principally in the physical layout of components on the silicon die. Id. ¶ 62.
Result. Both the claimed "coherent detection module" and the accused element achieve substantially the same result: high-fidelity recovery of the amplitude and phase information of the transmitted optical signal, enabling high-bandwidth coherent optical communication. Dr. Ashford's analysis of Benchmark's teardown data confirms that Lumicore's accused products achieve signal-recovery performance metrics (e.g., bit-error rate, signal-to-noise ratio, constellation diagram quality) comparable to those achieved by implementations practicing the literal claim language. See Exhibit 6 ¶¶ 66–72.
Corroborating evidence. The function-way-result analysis is further supported by Benchmark Semiconductor Analysis, LLC's teardown reports. Benchmark's Lead Engineer, Kevin Ng, conducted detailed reverse-engineering analyses of the LumiLink 400G-ZR+ (December 12, 2022 teardown report) and LumiLink 800G-DR8 (June 2023 teardown report), including die-level optical and electron microscopy, layer-by-layer deprocessing, and functional testing. Mr. Ng's reports document the structural similarity between OWS's patented coherent detection module and Lumicore's implementation, identifying the same functional building blocks — local oscillator, signal splitter, phase-diverse detection elements, and balanced or quasi-balanced photodetection — present in both designs. See Exhibit 3 (excerpts from Benchmark teardown reports). At his January 7, 2025 deposition, Mr. Ng testified that "the accused structures employ the same functional building blocks with variations in physical layout" and that, from an engineering standpoint, "the Lumicore receiver front-end is recognizably doing the same job as the patented design." See Exhibit 5 (Ng Dep. Tr. at 87:14–88:3).
Moreover, Lumicore's own CTO, Dr. Sandra Michaud, admitted at her November 19, 2024 deposition that Lumicore's design team reviewed OWS's published patent application (Publication No. US 2018/0123456, corresponding to the '193 Patent) during the design phase for the LumiLink 400G-ZR+ product. See Exhibit 4 (Michaud Dep. Tr. at 142:8–143:12). This testimony is significant because it demonstrates that Lumicore was aware of OWS's patented approach and, at most, made targeted modifications to the physical topology of the receiver front-end while retaining the fundamental function, operating principle, and result of OWS's coherent detection module.
4. Lumicore's Anticipated Counter-Arguments and OWS's Responses. OWS anticipates that Lumicore will advance several arguments in support of its motion. None has merit.
Lumicore's likely argument: The amendment surrendered all equivalents in the "coherent detection module" space because the amendment was made specifically to distinguish over prior art relating to detection modules. OWS's response: This argument improperly conflates the subject matter of the amendment (detection modules generally) with the rationale for the amendment (distinguishing non-coherent detection from coherent detection). The Festo tangential-relation analysis focuses on the reason for the amendment, not merely its subject matter. Honeywell, 523 F.3d at 1315. The reason for the amendment was to distinguish Takahashi's direct-detection architecture, which is a fundamentally different detection paradigm. The amendment drew a line between non-coherent and coherent detection; it did not purport to narrow among different coherent-detection implementations. Lumicore's reading of the estoppel would convert the rebuttable Festo presumption into an irrebuttable bar — precisely the "complete bar" approach that the Supreme Court rejected in Festo itself. 535 U.S. at 737–38.
Lumicore's likely argument: OWS could have drafted broader claims to encompass Lumicore's specific coherent-detection topology. OWS's response: This argument invokes, at best, the Festo catch-all exception — and supports OWS's position under that exception. At the time of the narrowing amendment during prosecution, OWS could not reasonably have been expected to describe Lumicore's specific modified 90° hybrid topology because that topology had not yet been designed or conceived by Lumicore. The LumiLink 400G-ZR+ was not launched until Q3 2022 — more than four years after the '193 Patent application was filed and more than a year after the patent issued. There is no evidence that Lumicore's specific modified 90° hybrid configuration existed in the prior art at the time of the amendment. Accordingly, the catch-all exception applies as an independent basis for overcoming the Festo presumption, in addition to the tangential-relation exception.
Lumicore's likely argument: Dr. Rajesh Sundaram will opine that the accused designs are fundamentally different from the claimed invention. OWS's response: OWS anticipates that Lumicore will submit a declaration or expert report from Dr. Sundaram (Professor of Photonic Engineering at Pacific Western University) opining that the accused modified 90° hybrid topology differs fundamentally from the claimed balanced-detector configuration. To the extent Dr. Sundaram offers such opinions, they are directly controverted by Dr. Ashford's analysis, which explains in detail why the topological differences are insubstantial. Competing expert opinions on the function-way-result analysis are the paradigmatic example of a genuine dispute of material fact. This is a "battle of experts" that must be resolved by the jury, not by the Court on summary judgment. See Warner-Jenkinson, 520 U.S. at 38; Harborline Enterprises Davis, 62 F.3d at 1518–19.
C. The '015 Patent: Prosecution History Estoppel Does Not Bar the Doctrine of Equivalents for Claim 12
1. Background on the Narrowing Amendment. During prosecution of the '015 Patent, the examiner issued a rejection of certain claims under 35 U.S.C. § 103 as obvious over a combination of two prior-art references: U.S. Patent No. 8,412,007 to Bergmann ("Bergmann"), issued April 2, 2013, and International Publication No. PCT/EP2015/071234 to Simonsen ("Simonsen"), filed September 17, 2015. Bergmann disclosed a one-dimensional grating coupler for silicon photonic waveguides. Simonsen disclosed a two-dimensional periodic structure for optical applications but with a fill-factor relationship designed for a non-polarization-diverse application.
In response to the examiner's § 103 rejection, Dr. Chu of Cascade IP Advisors, LLC filed an amendment narrowing the "two-dimensional sub-wavelength grating" limitation in Claim 12 by adding language specifying a particular periodicity-to-fill-factor relationship in the grating structure. The prosecution remarks explained that the amended claims distinguished over the Bergmann/Simonsen combination because (a) Bergmann taught only a one-dimensional grating, not a two-dimensional sub-wavelength grating as claimed, and (b) Simonsen's two-dimensional periodic structure employed a different fill-factor relationship that was not designed for polarization-diverse coupling. The amendment added specificity to the periodicity-to-fill-factor relationship to establish that the claimed grating was optimized for polarization-diverse coupling in a manner that the Bergmann/Simonsen combination neither taught nor suggested. See Exhibit 2 (relevant excerpts from prosecution history of '015 Patent).
As with the '193 Patent, OWS acknowledges that this amendment constitutes a narrowing amendment made for reasons related to patentability and that the Festo presumption of surrender applies as a threshold matter. But the presumption is overcome for the same structural reasons discussed above: the tangential-relation exception applies.
2. The Tangential-Relation Exception Applies. The Bergmann/Simonsen combination presented fundamentally different deficiencies. The examiner's § 103 rejection rested on combining two references that, individually and in combination, presented deficiencies that were unrelated to the specific equivalent OWS asserts against Lumicore's products. Bergmann disclosed only a one-dimensional grating coupler — a fundamentally different structure from the two-dimensional sub-wavelength grating claimed in the '015 Patent. Simonsen disclosed a two-dimensional periodic structure, but one with a fill-factor relationship designed for a non-polarization-diverse application (i.e., Simonsen's structure was not engineered to manage both TE and TM polarization modes simultaneously).
The amendment addressed the Bergmann/Simonsen deficiencies, not Lumicore's specific implementation. The specificity added by the amendment — a particular periodicity-to-fill-factor relationship — was chosen to distinguish over the Bergmann/Simonsen combination by establishing that the claimed grating was a two-dimensional structure (unlike Bergmann's one-dimensional structure) with a fill-factor relationship optimized for polarization-diverse coupling (unlike Simonsen's non-polarization-diverse design). The amendment did not purport to narrow the claims to exclude all two-dimensional sub-wavelength gratings that achieve polarization-diverse coupling but happen to use a different periodicity-to-fill-factor ratio.
Lumicore's accused products use a two-dimensional sub-wavelength grating with a different periodicity-to-fill-factor ratio. The LumiLink 800G-DR8 and LumiEdge 1600G-LR employ two-dimensional grating coupler structures that achieve polarization-diverse coupling — the very function that the amendment was intended to protect. The only difference between Lumicore's implementation and the literal claim language is in the specific numerical value of the periodicity-to-fill-factor ratio. Lumicore's grating operates with a different ratio than the specific value recited in the amended claims, but it is nonetheless a two-dimensional sub-wavelength structure that achieves the same polarization-diverse coupling function.
The relationship between the amendment rationale and the accused equivalent is tangential. The amendment was directed at distinguishing a prior-art combination involving (a) a fundamentally different dimensional structure (Bergmann's one-dimensional grating) and (b) a non-polarization-diverse fill-factor design (Simonsen). The amendment was not directed at foreclosing two-dimensional sub-wavelength gratings with alternative fill-factor ratios that nonetheless achieve polarization-diverse coupling. The accused equivalent — Lumicore's two-dimensional sub-wavelength grating with a different fill-factor ratio — was not the subject of the prosecution exchange. The rationale for the amendment is "peripheral, or not directly relevant," to Lumicore's specific implementation. Honeywell, 523 F.3d at 1315. The tangential-relation exception applies.
Dr. Ashford's analysis confirms the tangential relationship. Dr. Ashford's prosecution history estoppel analysis memorandum, dated October 12, 2024, and her supplemental declaration of December 20, 2024, both confirm that the amendment's distinguishing rationale was directed at the specific deficiencies of the Bergmann/Simonsen combination and not at foreclosing the particular equivalent embodied in Lumicore's products. Dr. Ashford opines that a POSITA would understand the amendment as distinguishing between (i) one-dimensional gratings and non-polarization-diverse two-dimensional structures, on the one hand, and (ii) two-dimensional sub-wavelength gratings optimized for polarization-diverse coupling, on the other. A POSITA would not understand the amendment as surrendering equivalents encompassing all alternative two-dimensional sub-wavelength gratings that achieve polarization-diverse coupling but with a different fill-factor ratio. See Exhibit 6 ¶¶ 78–91.
3. The Function-Way-Result Analysis Creates a Triable Issue. Function. Both the claimed "two-dimensional sub-wavelength grating" and the accused element in Lumicore's products perform substantially the same function: coupling light from an optical fiber into a silicon waveguide while managing both TE and TM polarization modes. This functional identity is supported by Lumicore's own design documents, which describe the company's grating coupler as achieving "polarization-diverse coupling equivalent to state-of-the-art designs." See Exhibit 7 (excerpts from Lumicore internal design documents, designated Highly Confidential — Attorneys' Eyes Only). Dr. Ashford opines that the function of the accused element is identical to the function of the claimed limitation. See Exhibit 6 ¶¶ 92–97.
Way. Both the claimed limitation and the accused element operate in substantially the same way: using a periodic nanostructure with feature dimensions below the operating wavelength to create polarization-diverse coupling through diffraction of the incoming light into guided modes within the silicon waveguide. The difference lies solely in the specific periodicity-to-fill-factor relationship — a geometric parameter that, as Dr. Ashford explains, represents an insubstantial variation within the broader class of two-dimensional sub-wavelength grating designs. Dr. Ashford's analysis demonstrates that the alternative fill-factor ratio used by Lumicore achieves polarization-diverse coupling through the same physical mechanism (sub-wavelength diffraction) as the claimed ratio, with only minor differences in coupling efficiency at specific wavelength and polarization combinations. See Exhibit 6 ¶¶ 98–109.
Result. Both the claimed limitation and the accused element achieve substantially the same result: efficient, low-loss, polarization-insensitive fiber-to-chip optical coupling suitable for high-bandwidth transceiver applications. Benchmark's teardown reports for the LumiLink 800G-DR8 (June 2023) and LumiEdge 1600G-LR (February 2024) both confirm that Lumicore's grating coupler structures achieve coupling efficiencies and polarization-dependent loss metrics comparable to implementations practicing the literal claim language. See Exhibit 3.
Corroborating evidence. The function-way-result analysis for the '015 Patent is further corroborated by Benchmark's detailed physical analysis. Benchmark's teardowns revealed that Lumicore's grating coupler structures are two-dimensional sub-wavelength gratings with periodic nanostructure features that bear strong structural resemblance to the patented design. Benchmark's cross-sectional scanning electron microscopy ("SEM") images show a periodic array of sub-wavelength features etched into the silicon waveguide layer, with two-dimensional periodicity in both the longitudinal and transverse directions — the defining characteristic of the claimed invention. The only observable difference is in the specific geometric parameters (the periodicity pitch and fill factor), which Benchmark's optical simulation analysis indicates would produce only a minor shift in the coupling spectrum without fundamentally altering the polarization-diverse coupling behavior. See Exhibit 3.
Additionally, Lumicore's own internal design documents, produced in discovery, contain a presentation slide deck prepared by Lumicore's Photonic Design Group that describes the LumiEdge 1600G-LR's grating coupler as achieving "polarization-diverse coupling equivalent to state-of-the-art designs" and benchmarks its performance against "published 2D sub-wavelength grating coupler results." See Exhibit 7. This internal characterization powerfully supports OWS's contention that Lumicore's grating coupler is functionally equivalent to the claimed two-dimensional sub-wavelength grating.
4. Lumicore's Anticipated Counter-Arguments and OWS's Responses. Lumicore's likely argument: The amendment specifically addressed the fill-factor relationship, and Lumicore's different fill-factor ratio is precisely the territory surrendered. OWS's response: This argument conflates the subject matter of the amendment with the reason for the amendment, just as Lumicore's parallel argument does for the '193 Patent. The amendment added specificity to the periodicity-to-fill-factor relationship, yes, but it did so for the purpose of distinguishing a prior-art combination involving a fundamentally different dimensional structure (Bergmann's one-dimensional grating) and a different purpose for the fill factor (Simonsen's non-polarization-diverse design). The territory surrendered by the amendment is the territory occupied by one-dimensional gratings and non-polarization-diverse two-dimensional structures — not the territory occupied by two-dimensional sub-wavelength gratings that achieve polarization-diverse coupling with a slightly different fill-factor ratio. The latter territory is only tangentially related to the amendment rationale, and the Festo presumption is therefore overcome.
Lumicore's likely argument: The unforeseeability exception does not apply because two-dimensional gratings with different fill factors were known in the art. OWS's response: OWS relies primarily on the tangential-relation exception, not the unforeseeability exception, to overcome the Festo presumption with respect to the '015 Patent. OWS reserves the right to argue unforeseeability at trial if the evidence supports such an argument, but the tangential-relation exception is independently sufficient to overcome the presumption. Lumicore's attempt to defeat OWS's DOE contentions by challenging an exception that OWS does not principally rely upon is a red herring.
Lumicore's likely argument: Dr. Sundaram will opine that the fill-factor difference is substantial, not insubstantial. OWS's response: To the extent Dr. Sundaram offers opinions that the fill-factor difference between the claimed and accused grating structures constitutes a substantial difference, those opinions are directly controverted by Dr. Ashford's analysis. Dr. Ashford's simulations and calculations demonstrate that the fill-factor variation at issue produces only minor performance differences that do not alter the fundamental polarization-diverse coupling behavior. Whether the fill-factor difference is substantial or insubstantial is a quintessential factual question for the jury. The existence of competing expert opinions on this point creates a genuine dispute of material fact that precludes summary judgment. Warner-Jenkinson, 520 U.S. at 38.
D. Summary Judgment Is Inappropriate Because the DOE Analysis Is Inherently Fact-Intensive
The points made above with respect to the individual claim limitations underscore a broader principle: the doctrine of equivalents analysis is inherently fact-intensive and is generally not amenable to resolution on summary judgment. The Supreme Court has held that the function-way-result test under the doctrine of equivalents presents a question of fact for the jury. Warner-Jenkinson, 520 U.S. at 38. The Federal Circuit has likewise recognized that "the determination of equivalents is a factual one, to be submitted to the trier of fact." Harborline Enterprises Davis Chem. Co. v. Warner-Jenkinson Co., 62 F.3d 1512, 1518 (Fed. Cir. 1995) (en banc), aff'd, 520 U.S. 17 (1997). Whether the Festo tangential-relation exception applies is also a factual determination that should not be resolved on summary judgment where, as here, the evidence creates a genuine dispute. Insituform, 385 F.3d at 1370–71.
The current procedural posture further confirms that summary judgment is premature. Expert reports are not yet due — plaintiff's reports are due June 15, 2025, and defendant's rebuttal reports are due July 15, 2025. Expert discovery does not close until August 15, 2025. Although OWS has already disclosed substantial expert analysis through Dr. Ashford's declarations filed in connection with claim construction, the full function-way-result analysis and prosecution-history-estoppel rebuttal will be set forth in Dr. Ashford's forthcoming expert report. Resolving these factual questions on summary judgment before the expert record is complete would be particularly inappropriate.
Both sides have retained highly qualified technical experts whose opinions directly conflict on the material factual issues in this motion. Dr. Ashford, OWS's technical expert, holds a Ph.D. in Electrical Engineering and Photonics from Stanford University, has published over 120 peer-reviewed papers in the field of silicon photonics, and has served as a consultant to multiple semiconductor companies on photonic integrated circuit design. Dr. Sundaram, Lumicore's anticipated technical expert, holds a Ph.D. in Photonic Engineering from Pacific Western University and is expected to offer competing opinions on the function-way-result analysis and the scope of prosecution history estoppel. These competing expert opinions — grounded in the same underlying evidence but reaching opposite conclusions — are the hallmark of a genuine dispute of material fact. The Court should not arrogate to itself the role of weighing these competing opinions and choosing between them. That task belongs to the jury.
E. Additional Equitable Considerations
While the foregoing analysis is dispositive of Lumicore's motion, OWS respectfully submits that the equitable context of this dispute further demonstrates why summary judgment is inappropriate.
Lumicore's awareness of OWS's patents. The record evidence establishes that Lumicore was aware of OWS's patent rights during the design and development of the accused products. Most significantly, Dr. Sandra Michaud — Lumicore's Chief Technology Officer and the individual with ultimate technical responsibility for the accused product designs — admitted at her November 19, 2024 deposition that Lumicore's design team reviewed OWS's Published Application No. US 2018/0123456 (corresponding to the '193 Patent) during the design phase for the LumiLink 400G-ZR+ product. See Exhibit 4 (Michaud Dep. Tr. at 142:8–143:12). OWS also anticipates testimony from Melissa Chen, a former Lumicore engineer now employed at Veridian Photonics, Inc., who is expected to provide testimony regarding the extent to which Lumicore's design team was aware of and drew upon OWS's published patent applications in developing the accused products.
This evidence of awareness is relevant context for the DOE analysis. It suggests that Lumicore did not independently develop a fundamentally different approach to coherent detection or polarization-diverse grating coupling; rather, it adopted OWS's patented approach and made targeted — and, OWS contends, insubstantial — modifications to avoid literal infringement while retaining the substance of OWS's inventions. The doctrine of equivalents exists precisely to address this scenario: to prevent a copyist from "avoid[ing] infringement by making only trivial changes to the patented invention." Graver Tank, 339 U.S. at 607.
Lumicore's continued product launches after notice. The equitable concerns are heightened by Lumicore's conduct after receiving notice of OWS's patent rights. FairPoint Licensing Group, LLC — OWS's licensing agent — sent formal notice letters to Lumicore on January 15, 2023 and May 15, 2023, identifying the asserted patents and the accused products. An in-person licensing meeting was held on April 20, 2023, at which OWS's representatives presented detailed claim charts mapping the accused products to the asserted patents. Despite this notice, Lumicore proceeded to launch the LumiEdge 1600G-LR in Q4 2023 — a product that OWS contends infringes additional claims of the asserted patents. This pattern of conduct — awareness of OWS's patents, targeted design-around efforts, and continued product launches after notice — is the basis for OWS's willful infringement allegations and underscores why it would be inequitable to grant summary judgment foreclosing OWS's DOE contentions.
Lumicore should not be permitted to use narrow prosecution-history arguments to escape accountability for what are, at most, insubstantial design-around variations made with knowledge of OWS's innovations. The doctrine of equivalents exists to prevent precisely this result, and the fact-intensive questions at the heart of that doctrine must be resolved by the jury.
V. EVIDENTIARY SUPPORT
A. Declarations and Expert Opinions
OWS's DOE contentions are supported by the following declarations and expert opinions, which are part of the record or will be submitted contemporaneously with this Opposition:
1. Declaration of Dr. Caroline Ashford in Support of Plaintiff's Opening Claim Construction Brief (filed November 15, 2024, D.E. 44-1). Dr. Ashford's initial declaration set forth the POSITA definition for each asserted patent, the ordinary meaning of the disputed claim terms, and the technical context in which the claimed inventions operate.
2. Supplemental Declaration of Dr. Caroline Ashford in Support of Plaintiff's Reply Claim Construction Brief (filed December 20, 2024, D.E. 52-1). Dr. Ashford's supplemental declaration responded to the opinions of Dr. Rajesh Sundaram on claim construction issues and additionally addressed the prosecution-history-estoppel implications of the narrowing amendments to the '193 Patent and '015 Patent.
3. Dr. Ashford's Anticipated Expert Report (due June 15, 2025). Dr. Ashford's forthcoming expert report will contain a full function-way-result analysis for each DOE contention and a comprehensive prosecution-history-estoppel rebuttal, including her opinions on the applicability of the Festo tangential-re