US 10578437

I'll verify against live sources for litigation/docket activity, then summarize.

Let me check for the actual claim text and any PTAB activity.

Let me try to retrieve the issued claims directly.

US 10,578,437 B2 — Verification Summary

Scope note: I was able to verify bibliographic data, the abstract, and the full description from the authoritative Google Patents copy of the patent. I was not able to retrieve the verbatim granted claim text through the searches available to me, and I found no litigation, PTAB, or CAFC activity tied to this number. Where I could not verify something, I say so explicitly below rather than guessing.

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1. Bibliographic data (verified)

⚠️ One aggregator page (wiki.golden.com) renders the application number as "160265350." That is a machine-generated corruption; the authoritative USPTO-facing application number is 16/026,535. I flag it because the instruction was to interpret identifiers literally, and this one is simply wrong in that source.

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2. Post-grant / litigation check (negative result)

• USPTO / PTAB: I found no IPR, PGR, or other PTAB proceeding naming US 10,578,437 in the results I could reach. The PTAB-related pages returned were unrelated proceedings (e.g., Spero v. Mercedes-Benz, Apple v. Smart Mobile Technologies, Shockwave v. Cardiovascular Systems).
• CAFC 2026 dockets: I found no Federal Circuit appeal, Rule 36 judgment, or docket entry referencing US 10,578,437 in the 2025–2026 materials I retrieved.
• District court: I found no complaint, claim-construction order, or invalidity contention citing this patent.

Confidence caveat: These are negative search results across general web sources, not a direct query of the USPTO Patent Trial and Appeal Board API or the CAFC docket system (PACER/CM/ECF). A docket may exist that is not surfaced by general search. Treat the absence of litigation as unconfirmed rather than established.

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3. Abstract (verbatim from the patent)

"An optical sensor includes an optical device including a microresonator, laid out to guide a light beam along a closed loop optical path, and an injection and/or extraction waveguide, optically coupled to the microresonator; a photodetector, arranged at the output of the injection and/or extraction waveguide; and an analysis device, receiving a signal supplied by the photodetector, and deducing therefrom information relative to a displacement. The microresonator is constituted of a plurality of elementary waveguides spaced apart from each other, and arranged one after the other according to a loop shaped layout. The optical sensor offers increased sensitivity to the measurement of nanometric displacements."

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4. Plain-language overview of the claimed subject matter

Critical caveat: The claim text itself was not available to me. The description (which I do have in full) is consistent with the following claim structure, and the Keywords/tagging metadata confirms that the terms "displacement," "optical sensor," "injection," and "extraction" appear in the claims. But the summaries below are reconstructed from the specification, not read off the granted claims. Do not treat them as verbatim limitations.

Likely independent claim 1 — the optical sensor (apparatus), three cooperating parts:

1. An optical device comprising:
   • a waveguide microresonator that guides light around a closed-loop optical path; and
   • an injection and extraction waveguide (or, alternatively, a separate injection waveguide and a separate extraction waveguide) coupled to the microresonator by evanescent coupling.
2. A photodetector at the output end of the waveguide.
3. An analysis device (electronic/computer comparator, e.g., a processor) that receives the photodetector signal, compares it against reference data, and derives information about a displacement within the optical device.

The point of novelty (the characterizing feature): the microresonator is not a continuous ring. It is built from a plurality of discrete "elementary waveguides" that are spaced apart from one another (separated by free spaces) and arranged end-to-end along a loop-shaped layout — a "segmented ring microresonator."

Why that matters (the stated technical effect):

• A moveable nanobeam positioned in the near field can slip between two elementary waveguides, where it cuts the optical path rather than merely perturbing the evanescent tail. This produces a large jump in resonance loss and/or phase, so the output signal changes sharply — far more sensitive than prior-art evanescent-only sensing.
• When the microresonator is suspended and "breathes" (radial contraction/extension), the interstitial gaps change, which changes the effective index of the guided mode, which shifts resonance wavelength in addition to the length change. The specification quantifies this as an 18% sensitivity improvement (δλ of 9.1 nm vs. 7.7 nm for the same 5.00→5.05 µm radius change; FIGS. 6A/6B).
• Because the elementary waveguides are physically separate, selected ones can be mechanically freed from the others (via trenches in a support plate, FIGS. 9A–9D; or omitted arms, FIGS. 8A/8B) so that external loads displace them, creating a switched/perturbed resonance.

Likely dependent claims / alternative embodiments the specification supports:

• The ancillary moveable element (nanobeam or membrane) is in the near field, dimension < 0.5 µm (preferably 10–300 nm), with paths either in the microresonator plane or vertically (Oz) out of plane.
• Multiple moveable elements acting together for greater signal swing.
• A monochromatic operating variant: the analysis beam sits at a single resonance wavelength and the photodetector is a simple photodiode; comparison is intensity-vs-reference rather than spectrum-vs-spectrum.
• A variant with no moveable element — instead the injection and/or extraction waveguide itself is suspended and displaced.
• Dimensioning rules: distribution pitch P < λ/(2·n_moy), preferably P < λ/(2·n_h), and practically P < 3 µm / 2 µm / 1 µm; wider elementary waveguides than the bus waveguide (w/W ≈ 2, range 1.8–2.2); fill factor l/P ≈ 0.5 (range 0.4–0.6); effective index of the microresonator mode ≈ that of the bus waveguide within 1–10%.
• Materials: silicon for IR (1–10 µm) or silicon nitride (Si₃N₄) for visible (0.4–0.8 µm); no cladding — the surrounding medium is the cladding.
• Suspension structures: central pedestal (D₁ = 0.25–0.75 × D₂), full-disc support plate (thickness ≥3× thinner than the waveguides), or peripheral/internal arms.
• Coupling zone alternatives: a width-tapered bus waveguide, or a segmented bus waveguide with pitch matched to the microresonator (FIGS. 10A/10B).

Note on claim scope: The specification states expressly that "the invention does not relate to the optical device with microresonator as such" — that device is the subject of a separate earlier application (FR 16 57222). So the claims here should be expected to be directed to the sensor (device + photodetector + analysis device), not to a bare microresonator.

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5. Points where I am explicitly uncertain

1. Verbatim claim text — not retrieved. Claim count, exact transitional language ("comprising" vs. "consisting"), and whether an independent claim is also directed to a method of measuring displacement are all unconfirmed.
2. Litigation status — negative result only; not a definitive clearance that no suit or PTAB filing exists.
3. Priority chain — Google Patents shows 2017-07-04 priority while the body cites FR 16 57222 (27 July 2016). The precise French priority document(s) and whether there is a 2016/2017 dual-priority chain is not verified from the material I retrieved.
4. FIG. 11 manufacturing method — described in the specification as part of the disclosure, but whether it was claimed is unknown.

If you need the exact claim set, the reliable next step is a direct pull of the USPTO PatentCenter / Patent Public Search document for application 16/026,535 or the granted B2 text from the USPTO full-text database, which I was unable to reach in this session.

I'll search for litigation involving US patent 10578437 across patent litigation sources.

Let me search more targeted litigation databases and the patent's owner.

Summary of Search Results — Litigation Involving US Patent 10,578,437

No litigation involving US Patent 10,578,437 was found.

I searched for the specific patent number 10,578,437 across general web results, patent-litigation-related sources, and documents referencing the patent's owner (Commissariat à l'Energie Atomique et aux Energies Alternatives, "CEA"). None of the results returned any court case, complaint, docket, or proceeding in which US 10,578,437 is identified as an asserted patent.

What I checked and what came back

1. Direct searches for "10578437" + litigation / lawsuit / infringement / Unified Patents / court case — All returned only the patent's own bibliographic and full-text pages (Google Patents, Justia Patents, Patents-Review, a wiki mirror), plus a UK Gazette company-listing PDF where the digit string "10578437" appears as an unrelated company/registration entry — not the patent and not litigation. No docket, complaint, or case caption referenced the patent.

2. PTAB / IPR petitions (PTAB CTS document search results) — The petitions that surfaced (e.g., Unified Patents petitions) concerned entirely different patents (the '991 patent, the '779 patent, etc.) and different owners (Ozmo Licensing, Nuvoton/Panasonic). None referenced US 10,578,437.

3. CEA as plaintiff/owner — CEA has historically been a prolific litigant (e.g., Commissariat à l'Energie Atomique v. Chi Mei Optoelectronics, Fed. Cir. 2005; Commissariat à l'Energie Atomique v. Samsung Electronics, D. Del. 2007; the MEMC/Soitec - CEA actions in D. Del. around 2008–2010). However, none of those cases involve US 10,578,437 — they concern CEA patents from the 1980s–1990s (LCD, SOI, insulator technologies). I found no case tying this 2020-issued patent to any suit.

Important caveats

• A negative result is not proof of absence. The patent's own Google Patents page shows a "Discuss" link but no litigation tab populated, and it does not list related litigation; Google Patents and the sources I could reach may not be complete for all jurisdictions (e.g., district court cases, ITC Section 337 actions, or foreign proceedings).
• US 10,578,437 issued 2020-03-03 (app. 16/026,535, filed 2018-07-03, priority FR 1756293, 2017-07-04) and is owned by CEA. It has a counterpart EP 3 425 344 B1 and FR 3 068 778 B1. I found no assertion activity for any of these family members either, but I could not exhaustively verify foreign litigation.

Bottom line

Based on the sources I was able to search, there is no known patent litigation involving US 10,578,437. The searches turned up no plaintiff, defendant, jurisdiction, case number, or status because no such case appears in the reachable records. To be fully certain, the definitive checks would be a paid litigation database (e.g., Docket Navigator, Lex Machina) and a direct search of PACER and the ITC EDIS under the patent number and under "Commissariat à l'Energie Atomique" — tools beyond what I could access here.

I'll start by verifying the structured data against live sources, then check for any proceedings the ODP hasn't indexed.

The initial searches surfaced nothing tied to this patent. Let me run more targeted checks.

Let me check a few final angles — assertion history and any Unified Patents / aggregator activity.

Proceedings overview

Zero (0) AIA trial proceedings on file. The structured "PTAB proceedings on file" block supplied with this task — sourced from the USPTO Open Data Portal (ODP) — reports no AIA trial proceedings for US 10578437 as of the most recent ingest, and my independent web checks on 2026-09-29 surfaced none either. There is therefore no breakdown to give: no active proceedings, no claims invalidated, no claims sustained, no settlements, no institution denials.

Bottom-line defensive posture for a defendant: the patent is untested at the PTAB, not "hardened." Every claim stands exactly as issued on 2020-03-03. There is no FWD to hang an estoppel argument on, no cancellation to point to, and no PTAB win for a patent owner to leverage. A defendant here faces a clean-slate validity fight — which cuts both ways: no claim is dead, but the patent owner also has no PTAB validation of any claim.

Per-proceeding detail

None to report. I will not manufacture proceeding numbers, panels, or dispositions. The only IPR-flavored reference anywhere near this technology in my searches (e.g., IPR2025-01098 re US 8,860,337; IPR2025-00372 re US 9,917,563) concerns entirely unrelated patents and must not be attributed to US 10578437.

Strategic summary

Claim status — all claims LIVE and UNTESTED. No claim of US 10578437 has been canceled, disclaimed, or held unpatentable in any AIA trial. The patent issued 2020-03-03 from Application 16/026,535 (filed 2018-07-03), claims priority to 2017-07-04, is currently Active, and carries an anticipated expiration of 2038-07-03. Claim 1, as reproduced in the public claim set, is directed to "[a]n optical sensor comprising: an optical device comprising a waveguide microresonator, laid out to guide a light beam along a closed loop optical path, and an injection and extraction waveguide, or an injection waveguide and an extraction waveguide, optically coupled to the microresonator…" — with the inventive hook being the segmented microresonator "constituted of a plurality of elementary waveguides, spaced apart from each other, and arranged one after the other according to a loop shaped layout." (Caveat: the patent text I was given truncates before the full claim set is reproduced, so I have not independently verified the exact total claim count or the full dependent-claim ladder. Do not rely on a claim count from this memo — pull the issued claims.)

Estoppel landscape — essentially empty. Because no IPR/PGR was ever instituted, 35 U.S.C. § 315(e)(2) estoppel has not attached to anyone. No petitioner, and no privy of any petitioner, is barred from raising any § 102/§ 103 ground in a district court or ITC case. Conversely, there is no prior PTAB record to borrow: a defendant must build its invalidity case from scratch. Practical consequence: every printed publication, patent, and public-use/system art theory is on the table, and the challenger is free to choose between a district-court invalidity defense, a new IPR petition, or both (subject to § 315(b)'s one-year bar from service of a complaint and the Fintiv-successor discretionary-denial practice).

Pattern signals.

• Same-petitioner serial filings: none — there is no petitioner at all.
• Patent owner PTAB aggression: none — CEA has not appealed any PTAB outcome on this patent (there is none to appeal). The owner is a French public research body (Commissariat à l'Énergie Atomique et aux Énergies Alternatives), not a defensive-aggregator target or a serial litigant on this asset. Note for context: CEA has litigated historically — e.g., Commissariat a l'Energie Atomique v. Chi Mei Optoelectronics Corp., 395 F.3d 1315 (Fed. Cir. 2005) — but that was a personal-jurisdiction case on unrelated display technology, and I found no assertion of US 10578437.
• Assertion signal: none found. I found no district court complaint, ITC investigation, or demand-letter campaign citing US 10578437. This is the most plausible explanation for the zero-IPR count: the patent appears unasserted, and unasserted patents do not attract IPRs. It is not evidence that the claims are strong.

Family context worth flagging. US 10578437 sits in a small family: the sibling US 10,677,988 — "Optical device with segmented ring microresonator" shares the segmented-elementary-waveguide disclosure, and the priority chain traces to FR 16 57222 (filed 2016-07-27). The patent's own specification states the optical device "is described in detail, and protected as such, in… FR 16 57222," and expressly disclaims that the earlier application describes the analysis-device aspect. If you ever do mount a validity challenge, the parallel prosecution of US 10,677,988 and the FR priority filing are the first places to look for prosecution-history admissions and for the applicant's own characterization of the "segmented ring" concept versus the prior art (Sauer, Nanotechnology 25 (2014); Tallur, Optics Express 19(24) — both cited on the face of the patent as the closest known art).

Recommended next steps

1. Do not plan around a PTAB win that does not exist. There is no Final Written Decision to cite, no canceled claim to lean on, and no statutory disclaimer in the record. If you are drafting an invalidity contention or an IPR petition, you are starting from zero. If you are defending against a demand letter, demand that the plaintiff identify which claims it reads on your product — with all claims live, a broad assertion is possible.

2. Verify the zero-count yourself before relying on it. ODP ingestion lags. Run these three checks:

   • USPTO PTAB End-to-End / PTAB Center proceeding search: https://ptab.uspto.gov (search by patent number 10578437)
   • Google Patents "PTAB proceedings" and "Legal Events" tabs: https://patents.google.com/patent/US10578437/en
   • CourtListener docket search for the patent number: https://www.courtlistener.com/
     A recently-filed petition can sit unindexed in ODP for weeks; if a § 315(b) one-year window is running against anyone, a just-filed petition may not yet appear.

3. If you are a defendant contemplating an IPR, calendar the statutory clock. Once a petition is filed, institution is due within 6 months, and the PTAB's FWD deadline is a statutory 1 year from the institution decision (extendable ~6 months for good cause). With no prior petition, you are free of § 315(e)(2) estoppel exposure until you file — after which any ground you raised or reasonably could have raised is estopped in the parallel litigation.

4. Watch the sibling. Monitor US 10,677,988 and any continuation filings off the FR 16 57222 chain. A continuation issuing with claims closer to a commercial product is the single most likely trigger for the first-ever IPR against this family.

5. The absence of PTAB activity is a signal about assertion, not validity. Say it plainly to whoever asked: US 10578437 has never been tested at the Board. Treat all issued claims as live, enforceable, and available to a future plaintiff.

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Sources and confidence. Canonical proceeding list: the USPTO ODP-derived "PTAB proceedings on file" block in this prompt (zero proceedings). Patent bibliographic and specification data: https://patents.google.com/patent/US10578437/en (fetched 2026-09-24) and https://patents.justia.com/patent/10578437. Family/sibling confirmation: https://patents.justia.com/patent/[10677988](/patent/10677988) and https://patents.justia.com/patent/20180039024. Web searches for proceeding numbers, petitioner names, FWDs, and CAFC appeals returned no hits tying any AIA trial to US 10578437 as of 2026-09-29. I did not locate any PTAB E2E paper, FWD, or CourtListener docket for this patent, and I have stated no disposition, panel, or date that I could not verify.

I'll research the assignment record for US 10,578,437 directly.

Assignment Record — US Patent 10,578,437

Data-access caveat (read first). The live USPTO Patent Assignment Search / Assignment Center interface (assignmentcenter.uspto.gov, assignment.uspto.gov) does not expose its record contents to the search tooling available in this session. The only assignment event I can positively confirm for this patent comes from the Google Patents legal-events record of the patent itself, which shows a single post-filing assignment. I could not retrieve the reel/frame numbers, the correspondent of record, or the execution date. I am flagging that gap rather than inventing a reel number. If a later pass has direct Assignment Center access, the only thing to verify is the reel/frame and correspondent for that single 2018-08-29 record.

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Inventors

Pattern note: All three inventors appear to be employees of the same institution that took the assignment (CEA), which is the ordinary employee-invention picture for a French public research establishment (CEA is an établissement public à caractère industriel et commercial, EPIC). I found no evidence of any inventor departing the assignee within 12 months of filing, and no evidence of inventor-retained rights — but note this is an absence of evidence in the sources I could reach, not an affirmative verification. No independent-inventor or university-faculty anomaly is present on the face of the record.

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Original assignee

Commissariat à l'Énergie Atomique et aux Énergies Alternatives (CEA) — French Alternative Energies and Atomic Energy Commission, 31/33 rue de la Fédération, 75752 Paris Cedex 15, France (registered office used on CEA patent filings of this era).

• Entity type: French public research body (EPIC), government-mandated. Its micro/nanoelectronics and photonics work is centered at CEA-Leti (Grenoble), which is the practical R&D home of this subject matter.
• Line of business: Government-funded research and technology transfer across nuclear energy, defense, and micro/nanoelectronics; like most national labs, IT does not act as a merchant supplier of the claimed sensor. The commercial route is licensing and industrial partnerships through CEA's tech-transfer arm, not a product SKU.
• Product embodying the claims: No commercial product is known to embody the claims; the sensor is a research demonstrator (the patent's own spectra/simulation data are modeled, not a catalog part). This matters for the NPE analysis below — the assignee is a research institution, not an operating product company, but it is also not a licensing-only shell.
• Current status: Operating (active as of the record). Not acquired, not dissolved, no bankruptcy.
• Family / priority: US app 16/026,535 filed 2018-07-03; priority FR 1756293 filed 2017-07-04; published US 2019/0011261 A1; granted 2020-03-03; anticipated expiry 2038-07-03. Counterparts include EP 3 425 344 B1 and FR 3 068 778 B1. A related earlier CEA application, FR 16 57222 (filed 2016-07-27), is expressly identified in the specification as the source of the underlying optical device; this patent is the sensor/analysis-device follow-on.

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Assignment timeline

Records located: 1 (one) post-filing recorded assignment.

• Execution date: not retrieved / recorded 2018-08-29 — Reel/Frame: not retrieved (see caveat)
  • Conveyance: Assignment (Assignment of Assignors' Interest) — the standard "assignment of inventors' interest" recordation accompanying a newly filed application.
  • Assignor: Boris Taurel; Salim Boutami; Laurent Duraffourg (all three named inventors, jointly).
  • Assignee: Commissariat à l'Énergie Atomique et aux Énergies Alternatives (CEA).
  • Correspondent: Not retrievable from the sources I could reach. No correspondent or law-firm field is exposed by the Google Patents legal-events feed, and the fetched full text of the patent omits the "Attorney, Agent or Firm" front-page field. This is precisely the field the task wants captured, so I am flagging it as an open item — it should be pulled directly from the Assignment Center record or from column 1 of the printed patent. I have not inferred a firm name.
  • Context: Employer/employee assignment of inventors' rights to the original assignee — an internal, pre-issuance capture of title by the filing institution, not an acquisition, fire-sale, securitization, or transfer-to-asserter.

No further recorded assignments were found. In particular there is:

• No assignment to any "IP / Holdings / Licensing / Ventures" entity.
• No security agreement, merger, change-of-name, release, or correction record.
• No assignment away from CEA after issuance (grant date 2020-03-03).

Per the working rule in this exercise, an absence of post-issuance assignments is itself the finding: CEA remains the owner of record, and title never left the original research institution.

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Timeline diagram

timeline
    title Ownership of US 10578437
    2016 : CEA files FR1657222 for the optical device
    2017 : Priority FR1756293 filed 04 Jul
    2018 : US app 16026535 filed 03 Jul
         : Inventors assign to CEA 29 Aug
    2020 : US 10578437 B2 issued 03 Mar

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NPE / troll-pattern signals

1. Shell-entity transfer — Not present. The only transfer is inventors → CEA (recorded 2018-08-29). CEA is a government research body with a published statutory mandate, not an LLC, and no "IP/Patents/Licensing/Holdings/Ventures" successor appears anywhere in the chain.
2. Known asserter in the chain — Not present. CEA does not appear on the Acacia / Marathon / IV / Wi-LAN / Conversant / Pendrell / Round Rock / Spangenberg-type NPE rosters. Note the distinction from the litigation summary already generated for this patent: CEA has institutionally enforced older patents (e.g., the LCD and SOI actions in D. Del. and the Fed. Cir. against Samsung, Chi Mei, MEMC/Soitec), which is normal research-laboratory enforcement, not NPE conduct, and none of those cases involve this patent.
3. Repeat correspondent across the chain — Unclear / not assessable. With only one record and the correspondent field not retrieved, there is no basis to test recurrence. A single appearance would not be a finding anyway; this stays open only because the field is missing.
4. Cascading transfers — Not present. One recorded assignment; no chained LLCs, no shared-address cluster, no sub-24-month cascade.
5. Pre-litigation transfer — Not present. No infringement suit naming this patent was found (consistent with the litigation summary), so there is no assertion date to measure the 2018-08-29 recordation against.
6. Bankruptcy fire-sale — Not present. CEA has not filed Chapter 7/11; no proceedings sale.
7. Privateering — Not present. No transfer to any NPE asserting on CEA's behalf; title stayed with CEA.
8. Defensive aggregator (anti-NPE) — Not present. The chain does not terminate at RPX, AST, LOT, Unified Patents, or OIN.

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Verdict

Insufficient data — under the strict definition supplied ("no records, or only the original assignment"). The record I can confirm consists of exactly one instrument: the inventors' assignment to CEA recorded 2018-08-29 (US app 16/026,535, filed 2018-07-03, priority FR 1756293 of 2017-07-04). Every affirmative NPE signal above is absent, and the single assignment is a routine employer capture of title by a government research institution — so while the category is technically "insufficient data," the data that does exist points away from any NPE pattern: title never left CEA, and no downstream shell, aggregator, or asserter appears in the chain. The residual uncertainty is purely the un-retrieved reel/frame and correspondent on that one record, which is an access limitation, not an evidentiary gap in the ownership story.

Verification links:

• USPTO Assignment Center: https://assignmentcenter.uspto.gov/
• USPTO Patent Assignment Search (index): https://assignment.uspto.gov/patent/index.html
• Patent record (legal events): https://patents.google.com/patent/US10578437/en

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Open items for a follow-up pass with database access

1. Reel/frame for the 2018-08-29 record (should be a 2018-vintage reel in the ~050xxx–051xxx series).
2. Correspondent of record for that recordation, plus the "Attorney, Agent or Firm" field from the printed patent — check against CEA's usual US prosecution firms to confirm the assignment was filed by CEA's prosecution firm, not an unrelated recording agent (which would itself be a mild tell).
3. Confirm whether EP 3 425 344 B1 / FR 3 068 778 B1 show any recorded transfer at the EPO/INPI that is absent from the US record (a divergence would be worth flagging).

I'll research US Patent 10,578,437 and its cited prior art references.

Let me get the full citation list from the patent's Google Patents page and Justia.

Let me look for the specific citation lists on the patent's pages.

Prior-Art Analysis — US Patent 10,578,437 B2

1. Patent identification (verified against the authoritative full text)

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2. Important provenance caveat (read before relying on the list below)

The literal task — "search the USPTO database … look at each patent citation" — requires the USPTO PatentCenter "References Cited" / PTO-892 and applicant IDS for application 16/026,535. I was not able to open PatentCenter or the full PTO-892 in this session. What I retrieved is the citation data as rendered on Google Patents / Justia / Patents-Review mirrors for this exact patent (10,578,437 B2 / US 2019/0011261 A1). Therefore:

• The patent's own page reports "Patent Citations (7)" — i.e., a list of seven U.S. patent documents cited by/against this application. I was able to positively identify three of those seven below.
• I could not confirm the remaining ~four entries of the seven-document list from the sources reachable here. I will not invent them.
• The pre-grant publication's "References Cited" also carries two non-patent-literature items, which I can state with confidence because they are quoted verbatim in the patent's own PRIOR ART section.

I flag this explicitly rather than fabricate a complete twenty-reference list.

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3. Claim scope relevant to the § 102 analysis

The fetched authoritative text did not include the claims verbatim (the HTML capture contains title/abstract/description but not the numbered claim set). Reconstructing from the "DESCRIPTION OF THE INVENTION" statement of the objective, claim 1 is directed to an optical sensor comprising:

1. an optical device including (a) a waveguide microresonator laid out to guide a light beam along a closed-loop optical path, and (b) an injection and extraction waveguide (or a separate injection waveguide + extraction waveguide) optically coupled to the microresonator;
2. a photodetector at the output of that waveguide; and
3. an analysis device receiving the photodetector signal, configured to compare the signal with reference data and deduce information relative to a displacement within the optical device;
4. characterized in that the microresonator is constituted of a plurality of elementary waveguides, spaced apart from each other, and arranged one after the other according to a loop-shaped layout.

Dependent/embodied features that appear in the description and would drive claim differentiation: periodic distribution pitch P with P < λ/(2·n_moy) (eq. 3) and P < λ/(2·n_h) (eq. 4); length/pitch ratio l/P ≈ 0.5; width ratio w/W ≈ 2; suspended microresonator on a pedestal with "respiration" detection; moveable nanobeam/membrane ancillary element entering a free space; segmented or adiabatic-tapered coupling zone on the injection/extraction waveguide (Figs. 10A/10B); trenches isolating individual elementary waveguides (Figs. 9A–9D).

(This reconstruction is my reading of the description; treat the exact claim language as needing confirmation against the granted claims.)

Critical date: anything qualifying as prior art must predate 2017-07-04 (AIA § 102(a)(1)/(a)(2)). Almost everything cited here comfortably does.

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4. U.S. patent citations — item-by-item

4.1 US 2002/0039470 A1 — Braun, Alan Michael

• Full citation: U.S. Patent Application Publication 2002/0039470 A1, "Wavelength selective optical add/drop multiplexer and method of manufacture," inventor Alan Michael Braun; published 2002-04-04.
• Brief description: Ring/disk-type optical resonator add/drop multiplexers and their fabrication — wavelength-selective couplers between bus waveguides and a ring resonator, with detectors/monitors on the outputs. Representative of the generic waveguide-resonator coupling art.
• § 102 relevance: Possible § 102(a)(1)/102(b) art only for the generic elements: an optical microresonator, evanescent/coupled injection–extraction waveguides, and a photodetected output. It does not disclose a microresonator segmented into a plurality of spaced-apart elementary waveguides, nor an analysis device that compares a photodetector signal with reference data to output displacement information. It therefore does not anticipate claim 1 as a whole. At most it is background under § 103.

4.2 US 2009/0220184 A1 — Ramot at Tel-Aviv University Ltd. (Levy et al.)

• Full citation: U.S. Patent Application Publication 2009/0220184 A1, "Electro-Optical Modulator Structure," Ramot at Tel-Aviv University Ltd.; published 2009-09-03 (family including WO 2010/010527, US 7,613,367).
• Brief description: An electro-optical modulator built on a ring micro-ring resonator carrying a periodic defect structure (a periodic array of perturbations/photonic-crystal defects embedded in the ring), evanescently coupled to an input/output ridge waveguide, with a detector at the output. The document expressly notes that "the resonator of the present invention is configured and operable as a sensor," and the related Ramot disclosure (US 2006/0198567 / US 7,613,367, "Optical sensor and modulator") describes a deformable resonating structure in a waveguide channel whose deformation shifts the resonance wavelength, detected as a change in output light — i.e., nanotube/nano-displacement sensing.
• § 102 relevance: This is the most substantive patent reference of the three and the only one that touches (i) a periodically/segmented ring resonator and (ii) use for sensing a deformation. It is a candidate § 102(a)(2)/102(b) reference for the concepts of a periodically structured ring resonator coupled to a waveguide and interrogated optically. However, it does not disclose a ring formed of a plurality of physically separated elementary waveguides with interstitial free spaces in which a moveable element can intrude, nor the specific "respiration"-linked effective-index change of the invention, nor a claimed analysis device producing displacement information by spectral comparison. So it does not appear to anticipate claim 1, but it is the reference to watch for a § 103 obviousness attack on the "periodic structure in a ring" dependent claims.

4.3 US 55,202 A — 1866

• Full citation: U.S. Patent 55,202, "Improvement in sawing-machines," published 1866-05-29.
• Brief description: A 19th-century mechanical sawing machine. It has no technical relationship to waveguide resonators, photonics, or displacement sensing.
• § 102 relevance: None. This entry is almost certainly a Google Patents citation-parsing artifact (this same "US55202A / Improvement in sawing-machines" record recurs in the machine-extracted citation lists of many unrelated patents). I recommend it be disregarded until confirmed against the actual PTO-892. Likewise, the "novaluron" chemical-compound record that appears in the Google Patents keyword/"similar-document" indexing for this patent is a data-processing artifact, not prior art.

4.4 The approximately four unconfirmed entries of "Patent Citations (7)"

I could not retrieve the complete seven-document list. In a family like this, the unconfirmed entries would most plausibly be additional US application publications in the G01D5/353 / G02B6/2935 ring-resonator-sensor space, plus possibly the applicant's own FR 16 57222 counterpart. This must be verified directly in USPTO PatentCenter (see § 7).

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5. Non-patent literature cited (verified verbatim in the patent's PRIOR ART)

5.1 Sauer et al., Nanotechnology 25 (2014) — the closest prior art

• Full citation: V. T. K. Sauer, et al., "Optical racetrack resonator transduction of nanomechanical cantilevers," Nanotechnology, vol. 25 (2014).
• Brief description: Measurement of the displacement of a moveable nanobeam positioned in the near field of a cladding-less ring/racetrack waveguide microresonator; the nanobeam locally changes the cladding and hence the effective index N_eff and the resonance wavelengths λ = N_eff·2πR/m. This is exactly the prior-art architecture the patent opens with and improves upon.
• § 102 relevance: This is the strongest single-reference attack — but it is a § 102(a)(1) printed-publication reference and it fails on the characterizing feature: Sauer's microresonator is a continuous curved waveguide, not a plurality of spaced-apart elementary waveguides. It discloses the preamble of claim 1 (microresonator + waveguide + photodetection + displacement deduction) but not the "plurality of elementary waveguides … spaced apart … loop-shaped layout" limitation. Not anticipatory; highly relevant for § 103.

5.2 Tallur et al., Optics Express 19(24) — prior-art ring-resonator "respiration"

• Full citation: Siddharth Tallur, et al., "A monolithic radiation-pressure driven, low phase noise silicon nitride opto-mechanical oscillator," Optics Express, vol. 19, no. 24 (2011).
• Brief description: A continuous silicon-nitride ring microresonator and its radial contraction/extension ("respiration") modes.
• § 102 relevance: Anticipates only the background phenomenon (radial respiration shifting resonance) that the second embodiment of the '437 patent exploits. It does not teach a segmented ring, and therefore does not anticipate any claim requiring elementary waveguides. Relevant to § 103 and to the "improvement" argument at Figs. 6A/6B (δλ 7.7 nm → 9.1 nm, +18%).

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6. Same-family / related documents — express note

• FR 16 57222 → FR 3 054 664 B1 / EP 3 276 337 A1 (CEA, priority 2016-07-27), "Optical device with segmented ring microresonator." The '437 specification expressly says the optical device "is described in detail, and protected as such, in the patent application FR 16 57222, filed 27 Jul 2016," and expressly states that document "does not describe an optical sensor comprising an analysis device … and does not identify the advantages specific to the use of said optical device to obtain information relative to a displacement." Dates matter here: the EP equivalent (EP 3 276 337 A1) published 2018-01-31, which is after the '437 priority date of 2017-07-04, so it is not § 102 prior art against the '437 on its face. It is best treated as the applicant's own earlier disclosure defining the anticipatory baseline the '437 adds the "analysis device / displacement information" subject matter to. Do not mis-cite it as anticipating the '437.

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7. Bottom-line § 102 assessment

No single cited reference appears to anticipate claim 1, because every reference that teaches the ring-microresonator displacement-sensing preamble (Sauer; Tallur; Ramot/Levy) fails the characterizing limitation — a resonator built from a plurality of mutually spaced elementary waveguides separated by free spaces that a moveable element can intrude, and that close up/open up under "respiration" to change the effective index via eq. (2). That limitation is the novelty core, and it is also the subject of the applicant's own earlier FR 16 57222. Expect any validity challenge grounded in these citations to be run on § 103 (Sauer + Ramot/Levy, or Sauer + periodic-photonic-crystal ring art), not § 102.

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8. Recommended definitive checks (outside what I could reach here)

1. USPTO PatentCenter, application 16/026,535 → "Documents & Transactions" → the PTO-892s and the applicant IDS (SB/08), to obtain the literal, complete "Patent Citations (7)" list and any NPL list beyond Sauer/Tallur.
2. EP 3 425 344 B1 → the EPO European Search Report (and any Rule 71(3) art), which will supply a reviewed prior-art set for the same claims.
3. Global Dossier for the family, to capture the FR/EP search reports and any third-party observations.
4. Confirm that "US 55,202 A (Improvement in sawing-machines)" in the Google-rendered list is a parser artifact and not a genuine PTO-892 entry.

I have not auto-corrected any identifier; where I could not verify an entry, I have said so rather than filling the gap.

I'll ground the obviousness analysis with targeted searches on the key references before building the § 103 combinations.

Obviousness Analysis under 35 U.S.C. § 103

US 10,578,437 B2 — Displacement sensor with segmented ring microresonator (CEA)

Date note / provenance. The task header dates this analysis April 26, 2026 while the session clock reads 2026‑09‑29; nothing below turns on the difference. This memo builds on the four previously generated sections (Patent summary, Litigation summary, PTAB challenges, Assignment history, Prior art) and does not repeat their bibliographic or ownership content. Live searches run for this memo added several references that were not among the citations of record identified earlier; those are flagged as such.

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0. Bottom line

Claim 1 of US 10,578,437 is, on the art I can identify, vulnerable to a § 103 rejection but not to a clean § 102 anticipation. The novelty hook — "the microresonator is constituted of a plurality of elementary waveguides, spaced apart from each other, and arranged one after the other according to a loop shaped layout" — is, on its face, the defining architecture of the sub‑wavelength‑grating (SWG) / segmented‑metamaterial ring resonator, a device class that was mature, published, and applied to ring‑resonator sensing well before the 2017‑07‑04 priority date. The other two legs of the claim (evanescently coupled bus waveguide + photodetector; displacement extraction from the transmission spectrum) are squarely disclosed by Sauer et al., Nanotechnology 25, 055202 (2014), which the patent itself concedes as the starting point.

The strongest available challenge is therefore a three‑reference § 103 combination: Sauer (optomechanical displacement read‑out from a cladding‑less racetrack) + Tallur et al. (pedestal‑released SiN ring with radial "respiration") + SWG/segmented ring‑resonator art (Donzella 2015, Flueckiger 2016, Wang 2016), with US 2009/0220184 A1 (Ramot/Goldring) as a substitute or supplemental teaching that a ring resonator may itself carry a periodic segmented structure and be used as a sensor.

But — and this is the honest caveat — the analysis is reconstruction‑based. The granted claim set was not retrieved in the earlier passes and is not in the fetched full text. Everything below is keyed to the claim‑1 language as (a) parroted in the earlier PTAB section from public sources and (b) mirrored in the French grant FR 3 068 778 B1, whose "Exposé de l'invention" reproduces the claim structure verbatim: dispositif optique (micro‑résonateur à boucle fermée + guide d'injection/extraction couplé optiquement) → photo‑détecteur en sortie → dispositif d'analyse comparant le signal à des données de référence pour en déduire une information relative à un déplacement, caractérisé en ce que le micro‑résonateur est constitué d'une pluralité de guides d'onde élémentaires espacés les uns des autres et disposés les uns à la suite des autres selon un agencement en forme de boucle (FR3068778B1). Treat the mapping as tight on substance, provisional on exact claim numbering.

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1. Framework and assumptions

1.1 Governing standard

Obviousness is decided on the Graham v. John Deere, 383 U.S. 1 (1966), factual predicates (scope and content of the prior art; differences; level of ordinary skill; objective evidence) applied through the flexible KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398 (2007), framework. The relevant question is not whether the features of a secondary reference are "bodily incorporated" into the primary reference, but whether the claimed subject matter as a whole would have been obvious — In re Keller, 642 F.2d 413, 425 (CCPA 1981). MPEP § 2143's exemplary rationales (A)–(G) and § 2144.04 (design choice / optimization) govern.

1.2 Effective date and what counts as prior art

• Effective filing/priority: 2017‑07‑04 (FR 17 56293). Everything cited must predate that. All references in § 3 below do, except where flagged.
• FR 16 57222 (2016‑07‑27) family — do not treat as § 102 art against this patent. It is (i) a French filing, which is not secret prior art under AIA § 102(a)(2) (which reaches only US patents, US application publications, and PCT applications designating the US), and (ii) the applicant's own work, so any US/PCT counterpart would be subject to the § 102(b)(2)(C) common‑ownership exception. The earlier sections already flagged this as unresolved; the FR record now shows the chain cleanly (17 56293, déposé 04.07.17; earlier device work in FR 16 57222), and the EP counterpart of the earlier strand (EP 3 276 337 A1) published 2018‑01‑31 — after the priority date (FR3068778B1). It is the anticipatory baseline, not art.
• One point of internal inconsistency worth flagging: the earlier Prior‑art section named the FR 16 57222 counterpart as "FR 3 054 664 B1," while the Assignment and PTAB sections named "FR 3 068 778 B1" as the counterpart of this patent. Those are two different instruments (different priorities), not a conflict — but do not conflate them, and do not cite the earlier one as art.

1.3 Level of ordinary skill in the art (PHOSITA)

A person with an M.S. or Ph.D. in applied physics/electrical engineering and 2–5 years of hands‑on integrated‑photonics practice, including (a) design/simulation of SOI or Si₃N₄ micro‑ring resonators and evanescent bus coupling, (b) sub‑wavelength‑grating / effective‑medium waveguide design, and (c) at least working familiarity with NEMS/optomechanical transduction and release‑etch fabrication. This is the Sauer/Tallur/Donzella author profile — the art's own practitioners.

1.4 Claim‑construction caveats that matter for § 103

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2. The claimed subject matter, decomposed

Elements 1‑A through 1‑E are, respectively, a preamble, a known optical cavity, a known evanescent coupler, a known detector, and a conventional signal‑comparison step. If the challenge is to succeed, it succeeds on 1‑F, with 1‑E as the secondary battleground.

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3. The prior art of record — § 103‑relevant teachings

Only references that (i) predate 2017‑07‑04 and (ii) are actually reachable are listed. Each row states what it teaches and what it does not.

3.1 Additional art located in live search (not citations of record — a defendant would have to find these)

These matter because they close the 1‑F gap with art in the same field and, in one case, the same purpose:

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4. Gap analysis — one sentence

Every reference that supplies the displacement‑sensing preamble (Sauer; Tallur) uses a continuous ring; every reference that supplies the segmented/periodic ring (Donzella; Flueckiger; Wang; and, in defect form, Ramot/US 2009/0220184) uses it for a different primary purpose (biosensing sensitivity, slow light, or modulation). No single reference supplies both. That is precisely the fact pattern § 103 exists to address, and the case for combining is strong because the reason to segment and the reason to use a ring for displacement sensing converge on a single, shared objective: maximise the interaction between the guided mode and a perturbation in the surrounding medium.

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5. Grounds of rejection

Ground 1 (primary): Sauer + Tallur + Donzella/Wang (SWG ring)

Elements: Sauer → 1‑A, 1‑B, 1‑C, 1‑D, 1‑E. Tallur → pedestal‑released, photodetected ring and its respiration shift (confirming 1‑B/1‑D and supplying the second embodiment). Donzella/Wang (and Flueckiger for motive) → 1‑F.

Rejection logic (rule‑based):

1. Sauer already teaches that a near‑field mechanical element shifts a ring resonance and that the shift is quantitatively read out to yield a displacement (its eq. (8) recovers ||z||_TM,tip). Its own stated limitation is responsivity — the patent's preamble says the same thing ("L'influence de la nano‑poutre… reste cependant assez restreinte"), and Sauer's paper is about how responsivity scales.
2. Donzella/Wang teach that the same kind of ring may be built as a train of spaced silicon segments (sub‑wavelength grating), and Flueckiger teaches doing so expressly to increase the interaction of the resonant mode with the medium surrounding the ring.
3. Substituting the continuous ring of Sauer with a segmented SWG ring of the same footprint and radius is a substitution of one known resonator topology for another, in the same circuit, to achieve the same function — MPEP § 2143 rationale (B) — with a predictable effect (higher external‑field overlap ⇒ greater sensitivity to whatever perturbs the cladding/effective index), § 2143 rationale (A).
4. The '437's own numbers show the effect is one of degree, not kind: with the nanobeam inside a free space, the deepest transmission dip moves by ~8 percentage points and the same resonance family remains resolvable (Fig. 2). The patent itself says the losses "increase with a level of occupancy" — i.e., a monotonic, predictable relationship, not an unexpected result.

Reasonable expectation of success: High. Wang 2016 demonstrates a 5 µm‑radius SWG ring at Q ≈ 11,500 — the exact radius class the '437 uses (5 µm, 500 elements, 40 nm pitch) — so the PHOSITA had a working, low‑loss segmented ring in hand.

Ground 2: Sauer + US 2009/0220184 A1 (Ramot)

Same as Ground 1, but with the Ramot publication supplying the segmentation/periodicity teaching and the sensing‑use teaching. Ramot's express statement that the periodically structured ring is "configured and operable as a sensor" makes this the most on‑point citation for a motivation to modify a ring sensor's cavity. The gap: Ramot's periodic structure is a defect/corrugation scheme within the guide rather than physically separated elements, so the combination requires reading "spaced apart" onto Ramot's periodic voids/corrugations. Strengthened by adding Donzella as to the physical‑separation requirement. This grounds an alternative rejection and is also the natural secondary reference if a plaintiff argues the SWG art is non‑analogous (it is analogous — same field of endeavour: integrated‑optics ring resonators).

Ground 3: Tallur + Donzella/Wang + Sauer (for the respiration claims)

For any claim directed to the suspended microresonator / radial contraction‑extension embodiment (Figs. 5, 6A/6B, 7A–9D): Tallur supplies the pedestal‑released ring and its radial respiration; Donzella/Wang supply the segmented ring; Sauer supplies the "read the resonance shift and call it a displacement" step. The patent's asserted improvement — δλ of 9.1 nm vs. 7.7 nm for the same 5.00→5.05 µm radius excursion, "an improvement of 18%" (Figs. 6A/6B) — is exactly what equation (2)'s effective‑medium average‑index relation predicts once the fill factor l/P can change with pitch. Where the result is calculable from the known physics (Ortega‑Moñux 2017), KSR forecloses a non‑obviousness argument resting on that result. See § 9.

Ground 4: Sauer + Braun (and/or the Ramot detector disclosure)

For 1‑D and any claim reciting spectral dispersion means (prism/grating/filter) or a photodiode array: Braun discloses ring‑resonator add/drop structures with monitors/detectors on the outputs; the '437's own photodetector section ("spectral dispersion means such as a prism or a grating… onto a strip of photodiodes") is textbook spectrometer hardware. Rationale: familiar element, known method, predictable result — MPEP § 2143 rationale (F).

Ground 5: The "isolated zone / trenches" claims (Figs. 9A–9D)

For claims reciting a support plate cut by trenches isolating one or more elementary waveguides whose movement is freed: Tallur teaches that selected regions are released by timed undercut etch while a pedestal is retained for mechanical support; Wang/Donzella teach the segmented ring; Sauer teaches that a freed mechanical element adjacent to the ring is what you sense. Combining them — free one or more segments of the segmented ring instead of adding an external cantilever — is the use of a known technique (selective release) on a known structure to improve it in the same way (§ 2143 rationale (C)), i.e., increased mechanical compliance ⇒ more signal per unit external load. A PHOSITA reading the patent's own consistency requirement (P < λ/2n_h, eq. (3)) is told that displacement of an isolated segment is designed to fail to satisfy the guiding condition — again a predictable consequence of a known relation.

Ground 6: Considered separately — the dimensioning claims

If (and only if) the granted claims recite the pitch/fill‑factor/width relationships:

• P < λ/(2·n_h) (eq. 4) and "pitch less than the central wavelength" are the definition of the sub‑wavelength regime in the SWG literature (Halir 2015; Cheben 2017). A claim reciting this is anticipated/obvious over the SWG ring art standing alone.
• l/P ≈ 0.5 (0.4–0.6) is the canonical ~50 % duty cycle of SWG design (see Chang et al.'s measured DC ≈ 0.64–0.8 as fabrication spread, and the standard design point at 0.5) — design choice / optimization, MPEP § 2144.04, In re Aller.
• w/W ≈ 2 (1.8–2.2) is a width‑ratio arrived at by "electromagnetic simulation tools known to those skilled in the art," per the specification itself — i.e., routine optimization the patent concedes is conventional.

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6. Motivation to combine — the four rationales, with the evidence

(A) Combining prior‑art elements according to known methods to yield predictable results.
Sauer's interrogated ring and the SWG ring are the same component in the same circuit (ring + bus + detector + wavelength sweep). Replacing the ring core with a periodic segment train is a fabrication‑layer change on the same SOI platform (Tallur's and Wang's processes are both two‑mask SOI/SiN processes). Predicted result: same resonance physics, altered field distribution.

(B) Simple substitution of one known element for another to obtain the new element's known benefit.
Flueckiger 2016 is doing this exact substitution — replacing a strip‑waveguide ring with a segment‑based ring — and says why: "enhanced ring resonator biosensor," i.e., to increase the mode's interaction with the medium outside the guide. The '437 wants the same thing for the same reason (more sensitivity to a perturbing body in the near field). The substitution is compelled by the benefit the secondary art asserts for it.

(C) Use of a known technique to improve a similar device in the same way.
"Segment the ring, keep the pitch sub‑wavelength, and engineer the effective index via the fill factor" is a known photonic technique (Halir; Cheben; Donzella; Wang). Applying it to Sauer's optomechanical ring improves it in the identical respect (near‑field interaction strength).

(D) Applying a known technique to a known device ready for improvement, without a change in function.
Sauer's device is expressly a responsivity‑limited NOMS (its abstract and § 5 are about responsivity trade‑offs). A PHOSITA with a device "ready for improvement" and a published technique for improving exactly that property has the motivation.

(E) Market/demand pressure. Biosensing and inertial sensings' push toward higher‑sensitivity chip‑scale ring sensors (the Flueckiger/Yan/Huang body of 2015–2017 work, and the G01C19/727 classification that the USPTO itself placed on this patent, i.e., passive‑ring gyrometry) supplies a concrete, non‑speculative reason a practitioner would pursue a higher‑sensitivity ring displacement sensor.

(F) Finite number of identified, predictable solutions. For "raise near‑field sensitivity of a ring cavity," the field's solution set in mid‑2017 was small and well‑defined: (i) higher Q (already pushed), (ii) reduced mode volume, (iii) increase evanescent overlap via slot/SWG geometries (this path), (iv) photonic‑crystal cavities. A finite‑set case under KSR puts "obvious to try" in play as an alternative to a firm TSM.

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7. The secondary battleground — element 1‑E (the "analysis device")

This is where a well‑drafted claim would live, and a challenger must not ignore it.

• Sauer already performs 1‑E. Its eq. (8) recovers absolute displacement from (a) the slope ∂T/∂φ measured against the DC transmission spectrum and (b) known cavity parameters. That is "compare the photodetector signal with reference data, and deduce information relative to a displacement" in substance. A plaintiff arguing that "reference data" means a stored prior spectrum (the '437's t₀ vs. t₁ comparison) must reckon with Sauer's calibration‑based extraction, which is the same thing reduced to a stored curve.
• Even if the art lacks a literal electronic comparator, "a processor programmed to compare two data sets and output a result" is a classic familiar element deployed per known methods (§ 2143 (F)); see also In re Venner and MPEP § 2144.04 for the automation of a previously manual comparison step. The specification itself says the displacement calculation "will not present any difficult per se for those skilled in the art, specialists in the use of microresonators for measuring a displacement" — an admission that 1‑E's implementation is routine.
• Counter‑risk: if the granted claim 1 recites a specific comparison protocol (e.g., comparing wavelength values at local minima), and if the examiner allowed over the art on that, a challenger must supply an interrogation/lock‑in or WDM reference to reach it. Sauer's use of spectral minima is close, and the "optical down‑mixing"/WDM interrogation techniques in the Sauer group's own follow‑up literature (Sauer 2015 Opt. Lett.; "Optomechanical nanoresonator readout with optical downmixing") are the natural secondary references.

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8. Teaching away, and the patent owner's best rebuttals

A competent patent owner will make four arguments. Each has a designed answer.

(1) "The art taught away from segmenting a resonator, because segmentation destroys Q." Wang 2016 concedes SWG micro‑ring resonators "suffer from large bend losses when miniaturized" and "can only provide a moderate quality factor (∼5600) with a pretty large radius (e.g. 15 µm)."
Answer: that is a problem to be solved, not a categorical discouragement, and the very same reference solves it — trapezoidal pillars yielding Q ≈ 11,500 at r = 5 µm. A reference that discloses the drawback and then removes it cannot be a teaching away. In re Gurley / W.L. Gore v. Garlock: the prior art must criticise, discredit or otherwise discourage the claimed solution; noting a design trade‑off does not.

(2) "The '437's elementary waveguides are cladding‑less; SWG segments sit in cladding."
Answer: Sauer's racetrack is itself cladding‑less (the patent admits this). Suspended SWG structures with air gaps (Penades 2014/2016) and water‑clad SWG rings (Flueckiger; Chang) bracket the requirement, and the specification treats the surrounding medium (including air) as the cladding. The "no cladding" feature is a property of the environment, not a separate structural limitation the art fails to meet.

(3) "The combination is improper because the secondary art is non‑analogous."
Answer: Not so — Donzella/Flueckiger/Wang are integrated‑photonics ring resonators, the identical field of endeavour; and in any event the problem they address (increase the resonant mode's interaction with the environment to raise sensitivity) is the same problem the '437 addresses. In re Bigio / In re Clay.

(4) "Objective evidence rebuts: an 18 % sensitivity gain is unexpected."
Answer: see § 9.

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9. Objective evidence (secondary considerations)

Note: secondary considerations must be commensurate with the claim scope. Here the patent device's measured benefit attaches to the respiration embodiment, while claim 1 (as reconstructed) is the broader sensor claim; any nexus argument must bridge that gap.

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10. Probability assessment and failure modes

Where the challenge is strong: 1‑B/1‑C/1‑D are conceded by the patent's own prior‑art discussion; 1‑F is thin because the segmentation concept was a well‑developed art; the motivation is nearly express (Flueckiger's "enhanced ring resonator" purpose); the objective evidence is weak.

Where the challenge could fail:

1. Claim text. If the granted claims recite features not surfaced in the description‑based reconstruction — a specific comparison regime, a specific "occupancy" threshold, a specific trench‑isolation geometry with claimed numbers — the combination must be extended to reach them. Until the claim set is pulled, the confidence ceiling on any ground is well below "certain."
2. "Spaced apart" vs "periodically patterned." If a court construes 1‑F to require mechanically independent segments with free space between them (not a defect pattern inside a solid guide), a challenger must lead with Donzella/Wang (physical segments) rather than with Ramot, and must establish that the SWG gaps are the "free space" the claim describes. This is a construction fight worth briefing early.
3. Teaching‑away fight over both the Q penalty (Wang's admission) and the fact that both closest art references deliberately avoid segmentation — Sauer's racetrack is continuous and Tallur's ring is continuous. The owner will hammer this. The answer (§ 8(1)) is solid but not risk‑free.
4. 1‑E as a non‑obvious combination. If the examiner allowed precisely because Sauer extracts displacement by calibration while the '437 compares sequential spectra, that distinction — thin as it is — may be the actual reason the patent issued, and it is the limitation most likely to appear in an infringement contention. Attack it with Sauer's spectral methods + a WDM/lock‑in reference.

Net: on the reconstructed claim, I would rate a § 103 challenge as more likely than not to be at least partially successful (i.e., to invalidate or force amendment of the broad claim 1), with meaningful residual uncertainty driven entirely by (a) the un‑retrieved claim text and (b) the "spaced‑apart/free‑space" construction. I am not asserting a § 102 case: no single reference anticipates.

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11. What to verify before anyone files or defends on this

1. Pull the granted claims. USPTO PatentCenter, application 16/026,535 → the granted B2 claim set; and the PTO‑892s/IDS to complete the "Patent Citations (7)" list that the earlier Prior‑art pass could only partially identify. Everything in § 5–§ 7 should be re‑run against the literal claim language.
2. Get the FR/EP search reports. The FR grant shows a "Liste des documents cités dans le rapport de recherche" (FR search report) and the FR record names the agent as BREVALEX (FR3068778B1) — this partly closes the earlier Assignment section's "correspondent not retrieved" open item for the French case; the US correspondent/"Attorney, Agent or Firm" field is still un‑retrieved and should be pulled from the printed patent's front page. The EP search report on EP 3 425 344 B1 will give a reviewed art set for the same claims and may already contain the SWG‑ring citations.
3. Retrieve the SWG ring references in full (Donzella 2015; Flueckiger 2016; Wang CLEO 2016; Ortega‑Moñux 2017; Halir 2015) and pin publication dates against 2017‑07‑04 — especially Ortega‑Moñux, whose 2017 volume predates the date but whose issue date must be confirmed.
4. Confirm the FR 16 57222 family's publication dates and any US/PCT member (family includes US 10,677,988 and US 2018/0039024 per the earlier sections). Do not cite any member as § 102 art unless it published before 2017‑07‑04 or is a US/PCT filing not subject to the § 102(b)(2)(C) common‑ownership exception.
5. Confirm that "US 55,202 A" and the "novaluron" record are parser artifacts and not genuine PTO‑892 entries (per the earlier Prior‑art section, they are artifacts).

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Sources

Patent text and French grant: US10578437B2; FR3068778B1 PDF.
Closest art: Sauer et al. 2014 (PubMed); Hiebert group publication list; Sauer et al. 2012 APL 100, 261102; Sauer 2015 Opt. Lett.; Sauer 2017 AIP Adv. (via CNRC reference list); Tallur et al. 2011 (Optica) and (PubMed).
Patent art: US 2009/0220184 A1 / US 8,195,011 B2 (Ramot), text.
SWG/segmented ring art (not of record): Wang et al., CLEO 2016; IEEE review reference list (Donzella 2015; Flueckiger 2016; Halir 2015; Ortega‑Moñux 2017; Cheben 2017); Flueckiger text mirror; Gao et al., Sci. Rep. 6, 19999 (2016); Penades et al., suspended SWG (2014/2016) via reference list.

Confidence. High on the legal framework and on the content of each reference's teaching (each was located in a primary or publisher‑adjacent source above). Moderate on the claim‑element mapping, because the granted claim text remains un‑retrieved. Low on any prediction of how a particular tribunal would weigh the teaching‑away and objective‑evidence arguments. Where the record contained two different French numbers (FR 3 054 664 vs. FR 3 068 778), I have flagged rather than reconciled them, per the operating rule against auto‑correction.