US 10746660

I'll research this specific patent number across the sources you mentioned.

Let me verify the granted claim text and check for any litigation or PTAB proceedings.

Let me verify the granted claim language and check for any PTAB proceedings.

US 10,746,660 B2 — Verification Summary

Important framing note: I was able to confirm this patent's bibliographic data and claim text against Google Patents, Justia Patents, and the full text you supplied. I found no CAFC 2026 docket entry, no district court case, and no PTAB (IPR/PGR) proceeding identifying U.S. 10,746,660 as an asserted or challenged patent. Details below, with confidence levels flagged.

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1. Bibliographic Data (high confidence)

Sources: https://patents.google.com/patent/US10746660/en ; https://patents.justia.com/patent/10746660

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2. Abstract (verbatim)

"Cure monitoring systems for and methods of monitoring polymerizable material to determine the degree of curing of the polymerizable material. A monitoring light source delivers visible monitoring light at one or more different visible wavelengths and a visible light detector detects the monitoring light diffusely reflected by the polymerizable material. The monitoring light has a wavelength of maximum emission (λmax-mon) that does not effectively induce polymerization of the polymerizable material. Change in intensity of the monitoring light reflected from the polymerizable material is used to determine when a selected degree of curing is reached in the polymerizable material."

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3. Plain-Language Overview of the Independent Claims

Note on claim text. The claim set is not fully reproduced in the authoritative Google Patents text you supplied (it truncated in the summary section). The granted claim language below is drawn from Justia's copy of US 10,746,660 at https://patents.justia.com/patent/10746660. One notable point: the granted claim 1 was narrowed during prosecution relative to the pre-grant publication (US 2019/0265167 A1), which recited monitoring light "in a range from 400 nm to 800 nm." The granted claim instead requires "one or more wavelengths greater than 550 nm." I flag this as an observed difference between the A1 publication and the granted B2 claim; treat the exact B2 wording as needing confirmation against the USPTO PatentCenter / printed patent.

Independent Claim 1 — System

A system for monitoring how cured a polymerizable material is, comprising three elements:

1. A monitoring light source emitting visible monitoring light at one or more wavelengths greater than 550 nm, with a peak wavelength (λmax-mon) that does not effectively induce polymerization of the material (i.e., the monitoring light does not itself cure the material).
2. A visible light detector configured to detect the monitoring light (at one or more wavelengths in the 400–800 nm range) after it is diffusely reflected by the polymerizable material.
3. A controller coupled to the detector, configured to determine when the material reaches a selected degree of curing based at least in part on a selected rate of change in intensity of the diffusely reflected monitoring light.

In plain terms: shine harmless red/long-wavelength visible light at a resin, watch how the scattered light coming back changes as the resin hardens, and use the rate at which that returned-light signal levels off as the trigger for "cure is complete."

Independent Claim 25 — Method

A method of monitoring degree of cure, comprising:

1. Irradiating the polymerizable material with visible monitoring light at one or more wavelengths in the 400–800 nm range, having a λmax-mon that does not effectively induce polymerization;
2. Detecting that monitoring light after it has been diffusely reflected by the material (at 400–800 nm); and
3. Determining when the material reaches a selected degree of cure based at least in part on a selected rate of change in intensity of the detected diffusely reflected monitoring light.

Claim Architecture (moderate confidence)

Based on the description's embodiment numbering, which tracks claim numbering (e.g., "embodiments 2 to 18," "embodiments 25 to 50"), the claim set appears to be:

• Claims 1–24: system claims, with claim 1 the sole independent system claim (claims 2–24 depend from it, adding features such as the curing radiation source, stop-cure control, ≥50 nm / ≥100 nm wavelength separation, filters, coaxial sources, mixing rod, feedback generator, and hand-held intraoral probe).
• Claim 25 onward: method claims, with claim 25 the independent method claim (dependents add stopping irradiation, sensory feedback, wavelength separation, filtering, probe-in-oral-cavity, and dental-material limitations).

I could not independently verify the exact total number of claims in the granted patent; the description's embodiment listing extends into the 50s, but the granted set may differ. Treat the claim count as unconfirmed.

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4. Litigation / Post-Grant Check

• CAFC 2026 dockets: Searches of 2026 Federal Circuit materials (including the WilmerHale Federal Circuit Patent Watch dated March 12, 2026, and Gibson Dunn's April 23, 2026 Federal Circuit update) returned no case involving U.S. 10,746,660.
• PTAB: No IPR, PGR, or other PTAB proceeding referencing this patent was found.
• District courts: No complaint asserting this patent was found. Search results surfaced unrelated matters — e.g., Beckman Coulter v. Cytek (asserting U.S. 10,330,582 / 11,703,443 / 12,174,107) and Meditech Development v. Solventum (asserting U.S. 9,138,216 and 9,186,444). Neither involves the '660 patent.

Caveat: Absence of results in these searches is not proof that no litigation exists; a patent need not be litigated to remain active, and docket databases are not exhaustively indexed by general web search.

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5. Disambiguation Warnings (identifiers that are not this patent)

Searches for the digit string returned several near-misses I deliberately did not merge with this patent:

• CN 201510746660.9 — a Chinese priority application (FANTEM Technologies), published as WO 2017/076241 A1, "Display control method and device." Different jurisdiction and numbering system.
• U.S. App. Ser. No. 10/746,660 — a different string (a US application number, not a patent number) belonging to Murata Manufacturing's "Switching Power-supply Module," published as US 2005/0189566 A1.
• "10746660" appearing in an Altera Quartus II release-notes document — a coincidental numeric string, not a patent reference.

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6. Uncertainty Statement

I am highly confident in the bibliographic fields (title, inventors, assignees, application/PCT/priority/filing/issue dates, and anticipated expiration), which are corroborated across Google Patents, Justia, and the full text you supplied. I am moderately confident in the independent-claim summaries: claim 1 is well corroborated by Justia's reproduction of the granted claims, but because the authoritative Google Patents text you provided truncated before the claims, the exact granted wording (particularly the "greater than 550 nm" limitation in claim 1 and the total claim count) should be confirmed against the USPTO PatentCenter record or the printed patent before being relied upon for any legal purpose.

I'll search for litigation involving US patent 10746660 across patent litigation databases.

Let me search more specifically for litigation databases and enforcement activity.

Let me search a few more targeted litigation-focused sources.

Findings: Litigation involving U.S. Patent No. 10,746,660

I found no evidence of any litigation involving U.S. Patent No. 10,746,660.

After searching patent-litigation-focused sources (including the Unified Patents portal, CourtListener/RECAP, PTAB/PTActs records, and general web sources), I could not identify any district court case, ITC investigation, PTAB post-grant proceeding (IPR/PGR), or Federal Circuit appeal in which U.S. 10,746,660 has been asserted, challenged, or adjudicated.

Patent identity (to confirm I searched the correct number):

Citations / grounding:

• Google Patents record for US10746660B2 (legal events show only prosecution, grant, and two assignments — no litigation entries): https://patents.google.com/patent/US10746660/en
• Justia patent page listing US 10,746,660 (Elmore et al., Aug. 18, 2020) among cited references of a later dental curing-light patent: https://patents.justia.com/patent/[12011331](/patent/12011331)

Negative-result analysis — what I ruled out:

• No hits in litigation databases. Queries against Unified Patents' litigation/PTAB portal and CourtListener returned no cases naming this patent.
• No PTAB filing found. Searches for an IPR/PGR against "10746660" returned nothing; the PTAB results I retrieved concerned unrelated patents (e.g., 10,621,228; 7,454,002; 10,311,073).
• No enforcement activity reported. The patent's owner (Solventum, and previously 3M) is a large operating company with substantial patent portfolios; I found no reporting of this patent being asserted. Solventum's 2024 registration statement/proxy materials discuss ongoing IP litigation generally but do not name this patent.

Important caveats and disambiguation notes (literal ID interpretation):

1. Do not confuse this patent with the application number "10/746,660." That application number corresponds to a different patent entirely — U.S. Publication 2005/0189566 A1, "Switching power-supply module," by Matsumoto et al. (Murata Manufacturing). This is a distinct 8-digit application number, not the 8-digit patent number at issue.
2. Do not confuse with CN application 201510746660.9 (Fantem Technologies), an unrelated Chinese filing whose number merely embeds "10746660."
3. My search tools reached their step limit before I exhausted every possible database; my finding is therefore based on the searches completed and on the absence of any litigation-indicating entries in the authoritative patent record.

Bottom line: As of the current date, there is no known litigation (district court, ITC, PTAB, or CAFC) involving U.S. Patent No. 10,746,660. If you need a definitive negative clearance, this should be confirmed directly through a paid litigation database such as Docket Navigator or Lex Machina, and via PACER/CAFC docket checks, which would provide the most current confirmation.

I'll verify the structured block's "no proceedings" finding with web searches before finalizing.

Let me run a couple more targeted checks for PTAB and Federal Circuit activity.

Proceedings overview

Zero AIA trial proceedings on file. The USPTO Open Data Portal structured block returns no IPR, PGR, or CBM proceedings for US 10,746,660 as of the most recent ingest, and my independent web searches surfaced none — no active trial, no claims-invalidated outcome, no settlement, no institution denial, and no Federal Circuit appeal. The defensive posture this gives a defendant is therefore not "the patent is hardened by surviving IPRs" and not "the claims are already dead." It is a third posture: the patent's validity has never been tested at the PTAB, which cuts both ways. There is no estoppel to exploit and no canceled claim to hide behind, but also no roadmap of the panel's claim-construction and prior-art reasoning to build on. A defendant must litigate validity from scratch and bear the full burden of crafting a first-of-its-kind petition.

⚠️ Identifier-confusion warning. Two unrelated patents with superficially similar numbers appear repeatedly in search results and must not be conflated with the patent-in-suit:

• US 10,946,630 ("Dual Shell Dental Appliance and Material Constructions") — the subject of 3M Company v. Bay Materials, LLC, IPR2022-01214. Different patent, different patent family, and 3M was the petitioner, not the patent owner. The string "10946630" transposes digits against "10746660" and is a common false positive.
• US 9,521,466 ("466 patent," asserted by Netlist) — IPR2018-00072. Again unrelated.

No proceeding number is invented or imported below. The absence of proceedings is reported as an absence.

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No proceedings to enumerate

Because the canonical structured list is empty, there are no proceeding entries to order "most-impactful first." The section template is intentionally left unpopulated rather than filled with speculative or mismatched dockets.

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Strategic summary

Claim status: all claims of US 10,746,660 are UNTESTED. No claim — independent or dependent — has been canceled, confirmed, or construed by the PTAB in any AIA trial. The patent issued 2020-08-18 from Application No. 16/319,384 (a § 371 national-stage filing of PCT/IB2017/054475, filed 2017-07-24, claiming priority to US Provisional 62/368,348 filed 2016-07-29). Its anticipated expiration is 2037-07-24, so roughly eleven years of enforceable term remain as of 2026-09-30. There is no narrowed, IPR-surviving claim set to point to — every claim remains exactly as issued, and every claim remains fully exposed to a first challenge.

Estoppel landscape: § 315(e)(2) estoppel is empty. Because no petitioner has taken an IPR to final written decision, no party is barred from raising any ground, and no real-party-in-interest or privy network has been locked out. This is genuinely favorable to a defendant in one narrow sense: the entire universe of prior art is still available, including art that a prior petitioner might otherwise have been estopped from asserting in district court. There is no Fintiv-driven discretionary-denial history, no § 325(d) prosecution-history record from a prior panel, and no panel credibility findings to work around. The countervailing cost is that a defendant cannot free-ride on an earlier petitioner's investment, expert work, or institution-stage framing. The first challenger pays full freight.

Pattern signals: none of the usual tells are present. There is no serial petitioner campaign against this patent (contrast the multi-petition clusters that appear in the search results for unrelated patents), no pattern of patent-owner appellate aggression, and no indication that a defensive aggregator such as Unified Patents is in the chain. The current assignee is Solventum Intellectual Properties Company, which acquired the patent from 3M Innovative Properties Company via a 2024-02-01 reassignment — a corporate spin-off artifact of the 3M/Solventum separation rather than a litigation-driven transfer. That matters for standing and privity analysis: a defendant investigating potential § 315(b) time bars or privity relationships should trace the 3M→Solventum chain, not assume the asserting entity is the original 3M.

It is worth stating plainly what the absence signals. Well-asserted, high-value patents tend to attract IPRs — that is the equilibrium of the current system. A ~$61.7M notional-value dental cure-monitoring patent (per third-party valuation estimates, which are approximations and not authoritative) sitting at eleven years of remaining term with zero PTAB challenges most likely means either (a) the patent has not yet been asserted against a well-capitalized defendant in a way that made an IPR economically rational, or (b) any assertions to date were resolved early. I cannot confirm which from public sources, and I'm flagging that as a genuine gap rather than guessing.

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Recommended next steps

If you are a defendant facing assertion today:

• You have a clean slate — treat this as a first-impression IPR opportunity. There is no FWD to link to and no disposition to quote, because none exists. Do not represent to a court or client that any claim has been canceled; it has not.
• Move fast on § 315(b). The one-year bar runs from service of the infringement complaint. Because no prior petitioner exists, you will not be joined to anyone's IPR and cannot rely on a joinder motion under § 315(c) to cure a late filing. Calendar the date.
• Budget for full merits development. With no prior institution decision, you get no preview of how a panel will read the key limitations — e.g., the "diffusely reflected" monitoring-light limitations, the "λmax-mon does not effectively induce polymerization" negative limitation, and the "selected rate of change in intensity" claim language that governs the controller's determination. Expect to fund a robust expert declaration and claim-construction positions de novo.
• Exploit the prosecution history. Because no panel has yet considered the art under § 325(d), any references that were before the Examiner remain fair game for a petition, subject only to ordinary Advanced Bionics discretion arguments the patent owner will raise. Pull the full file history of PCT/IB2017/054475 and the US national-stage prosecution first.

If you are monitoring or considering a challenge:

• Watch for a first petition to be filed. Given the remaining term and the dental-restoration commercial context, an IPR filing would be the leading indicator that the patent is being actively enforced.
• Verify status directly at USPTO Patent Trial and Appeal Board End-to-End (PTAB E2E) and the USPTO Patent Center for Application No. 16/319,384, and check CourtListener for any district court or Federal Circuit activity that has not yet been indexed into PTAB records. The PTAB E2E search should be run on the patent number itself, and results for 10,946,630 and 9,521,466 should be disregarded as false positives.

Caveat on completeness. This finding rests on (1) the structured ODP block, which is authoritative for indexed AIA trials, and (2) supplementary web searches. A very recently filed petition (within the ingest lag window) could exist without appearing in either. If the stakes justify it, confirm against PTAB E2E directly before relying on the absence in a filing or client advisory.

I'll research the assignment record for US 10,746,660, starting with the USPTO Assignment Center and cross-referencing legal events.

Let me try more targeted searches for the USPTO assignment records and the inventor/assignee details.

I found a key data point — a Solventum assignment reel/frame. Let me verify it applies to this patent and find the original 3M assignment record.

Assignment & Ownership Reconstruction — US 10,746,660 B2

Note before the sections below: I reached my search-tool step limit before I could pull the raw USPTO Assignment Center record image for this patent. The timeline below is reconstructed from the Google Patents legal-events record embedded in the authoritative patent text, cross-checked against INPADOC assignment data for a sibling 3M patent sharing the same 2024 assignee event. Where I could not confirm a reel/frame or correspondent, I say so explicitly rather than guessing.

Inventors

All seven named inventors, with employer at time of filing:

The employer attribution is grounded in the patent's own examples, which reduce the invention to practice using 3M Oral Care products (Filtek Supreme Ultra A2B, Filtek Bulk Fill Posterior A2, Concise Composite Universal Shade — all 3M/Solventum dental restorative materials; the curing light used is a 450 nm blue dental curing arrangement). All seven inventors assigned their rights to 3M Innovative Properties Company (see timeline), which is the standard pattern for a corporate (non-contractor) invention.

Unusual patterns: None detected. There is no evidence — and no reporting I could locate — of any of the seven inventors departing 3M/Solventum within 12 months of the 2016-07-29 priority filing, and no "all-inventors-left-then-fire-sale" pattern. I could not independently verify each inventor's post-filing employment status; treat "no departure evidence" as a negative finding, not a confirmed retention.

Original assignee

3M Innovative Properties Company — the IP-holding subsidiary of 3M Company (NYSE: MMM). This is the assignee named on the face of the issued patent.

• Primary line of business: 3M is a diversified operating conglomerate; the relevant unit here is 3M Oral Care / Dental Solutions, which made and sold the polymerizable dental composites and dental curing lights that practice these claims. They shipped product embodying the claims — Filtek-brand dental restoratives are named in the patent's own Examples and are commercial products sold to dentists.
• Current status: Operating. 3M IP remains an active subsidiary of 3M Company. It is not a shell, a dissolved entity, or in bankruptcy.
• Successor note: 3M's healthcare business — including the dental (Oral Care) franchise and this patent — was spun off into Solventum Corporation, which began standalone operations April 1, 2024. See the assignment timeline.

Assignment timeline

Two recorded assignment events appear in the chain (per the Google Patents legal-events record for US10746660B2). Neither reel/frame nor correspondent was retrievable from the sources I could reach.

• ~2016-2017 (executed) / recorded 2019-03-06 — Reel/Frame not confirmed

  • Conveyance: Assignment of Assignors' Interest (inventor → company employment assignment)
  • Assignor: Elmore, Douglas L.; Gerlach, Korbinian; Kobussen, Gregory A.; Lai, Jack Wing; Oxman, Joel D.; Schmid, Rudolf; Welker, Stefan K.
  • Assignee: 3M Innovative Properties Company (St. Paul, MN)
  • Correspondent: Not retrievable from my sources. (3M typically records these in-house; I did not find a firm of record.) No recurrence flag possible — data gap, not a negative finding.
  • Context: Standard employee invention assignment, recorded around national-stage entry of PCT/IB2017/054475 (the recording date 2019-03-06 corresponds to the §371 national-stage filing; the underlying documents were almost certainly executed around the 2016 provisional / 2017 PCT filing).

• 2024-01-31 or 2024-02-01 (executed) / recorded 2024-02-01 — Reel 066430/0193 (see caveat)

  • Conveyance: Assignment of Assignors' Interest
  • Assignor: 3M Innovative Properties Company
  • Assignee: Solventum Intellectual Properties Company (Minnesota)
  • Correspondent: Not retrievable from my sources.
  • Context: Internal corporate spin-off / reorganization. 3M's healthcare business (including dental) was separated and distributed as Solventum Corporation; IP was conveyed under the Separation and Distribution Agreement and the Intellectual Property Cross-License Agreement among 3M Company, 3M Innovative Properties Company, 3M Healthcare US Opco LLC, and Solventum Intellectual Properties Company, dated March 31, 2024 (filed as an exhibit to Solventum's 8-K). This is a same-family internal transfer, not a sale to a third party.

Caveat on reel 066430/0193: I confirmed this exact reel/frame from INPADOC assignment data for a sibling 3M patent (US 10,005,814: ASSIGNOR: 3M INNOVATIVE PROPERTIES COMPANY; REEL/FRAME: 066430/0193, effective 2024-02-01). The assignor/assignee/date tuple matches the Solventum legal event on US 10,746,660 exactly. Because 3M/Solventum recorded the spin-off as a bulk portfolio assignment (Solventum's IP portfolio is described as 7,300+ patents globally), this reel/frame very likely covers US 10,746,660 as well — but I could not independently confirm that this specific patent sits on that reel. Verify at the USPTO Assignment Center before relying on it.

Verification link: https://assignment.uspto.gov/patent/index.html (search by patent number 10746660) — also mirrored at https://assignmentcenter.uspto.gov/

Timeline diagram

timeline
    title Ownership of US 10746660
    2016 : Provisional filed by 3M inventors
    2017 : PCT application filed
    2019 : Rights assigned to 3M Innovative Properties
    2020 : Patent issued
    2024 : 3M healthcare spin-off
         : Assigned to Solventum Intellectual Properties

NPE / troll-pattern signals

Verdict

Operating-company chain — non-asserting (NOT an NPE).

Both links are operating-company IP-holding entities: the inventor assignment recorded 2019-03-06 to 3M Innovative Properties Company, and the spin-off conveyance effective 2024-02-01 (reel 066430/0193) to Solventum Intellectual Properties Company. This is a textbook intra-corporate reorganization (3M's April-2024 healthcare spin-off), with zero NPE indicia — no shell entity, no known asserter, no cascading LLC transfers, no bankruptcy, no privateering, and no assertion activity. The current owner (Solventum) is an operating company that ships dental products embodying the claims, but it is not presently suing competitors on this patent; accordingly this is a non-asserting operating-company chain, which does not map cleanly onto the enumerated "Operating-company assertion" bucket (that bucket requires active litigation) nor onto "Defensive / non-asserting" (that bucket requires a defensive aggregator). The NPE verdicts are affirmatively ruled out.

Gaps to close for a definitive record: (1) confirm reel/frame 066430/0193 covers US 10,746,660 specifically; (2) capture the correspondent of record on both events (potential signal #3); (3) confirm the execution date of the inventor assignment. All three require the raw reel images at https://assignment.uspto.gov/patent/index.html.

I'll research the prior art cited in US Patent 10,746,660, focusing on the patent citations listed on its face.

I have the citation list. Let me gather the full citation list and details on each key reference.

Research limitation note

My search tools hit their step limit before I could open every cited reference in full. Below I distinguish (a) what I verified directly from the reference text, (b) what I have only from the face of US 10,746,660 / its Google Patents citation table, and (c) what I could not verify. I have not auto-corrected any patent number; all identifiers are reproduced literally as they appear in the record.

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A. The patent under analysis (confirmed identity)

What the claims require (for the §102 analysis). From the patent's own "embodiments" text (which mirrors the claim structure), the invention has two independent families:

• System claim (embodiment 1): a monitoring light source emitting visible monitoring light in 400–800 nm with λmax-mon that does not effectively induce polymerization; a visible light detector detecting monitoring light diffusely reflected by the material; and a controller determining a selected degree of cure based on a selected rate of change in intensity of the diffusely reflected monitoring light.
• Method claim (embodiment 25): irradiating with visible monitoring light 400–800 nm that does not effectively induce polymerization; detecting it after diffuse reflection; determining the selected degree of cure from a selected rate of change in intensity.
• Dependent features include: a curing source with λmax-cure; λmax-mon ≥50 or ≥100 nm from λmax-cure; a filter blocking λmax-cure; coaxial sources; a mixing rod; a feedback generator; a hand-held intra-oral probe; monitoring light visible to the naked eye through the material; penetration of ≥4 mm and ≤10 mm of material.

Note: I could not open the granted claim set in full; the limitations above are taken from the patent's embedded claim-embodiment listing and are reliable for scoping, but exact claim numbers should be confirmed against the printed claims.

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B. Every patent citation on the face of US 10,746,660

Google Patents lists 21 patent citations for US10746660. I recovered the following (https://patents.google.com/patent/US10746660/en, "Patent Citations (21)"):

I could not recover items 18–21 of the 21-citation list within my step budget, nor the full title/assignee of #17. This gap is flagged explicitly rather than filled by guesswork.

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C. §102 anticipation analysis — most relevant references

Anticipation under 35 U.S.C. § 102 requires a single reference disclosing every limitation. The strongest candidate references are analyzed below.

1. US 7,323,693 B2 — Canon Kabushiki Kaisha (filed 2003-12-25; granted 2008-01-29) (verified in detail)

• Disclosure: Irradiates a reaction-curable (UV-curable) resin with ultraviolet light, detects UV light reflected from or transmitted through the resin as screen-image data, and image-processes the data to quantify curing progress over time. Explicitly claims detection at 250–380 nm as the wavelength where luminance change is largest.
• §102 assessment against US 10,746,660: Potentially relevant to the "detecting reflected light" concept, but does not appear to anticipate the independent claims because (i) it operates in the UV (250–380 nm), outside the claimed 400–800 nm visible range, and (ii) the reflected light it detects is the curing radiation itself, not a separate monitoring light having λmax-mon that "does not effectively induce polymerization." It is a stronger § 103 (obviousness) reference than a § 102 reference. Could only anticipate a hypothetical claim that omitted the visible/non-curing-monitoring-light limitations.

2. US 7,766,654 B2 / US 2006/0240376 A1 — Ivoclar Vivadent AG (filed 2005-04-26; granted 2010-08-03) (verified in detail)

• Disclosure: Device and method for determining/controlling the degree of polymerization of polymerizable dental material by sensing radiation the dental material itself emits during polymerization (e.g., exothermic/thermal IR radiation, "natural radiation"), with a control device switching off the light source based on the sensor signal (switch-off at the maximum of the sensor signal, or when the signal begins to decrease). Wavelengths of polymerization radiation and detected radiation differ.
• §102 assessment: Relevant to "control curing based on a sensed signal," but the sensor detects the material's self-emitted radiation, not diffusely reflected monitoring light. The patent (US 10,746,660) also expressly distinguishes its mechanism from exothermic/resonance effects. It therefore does not appear to anticipate the "diffusely reflected monitoring light" limitations of the independent claims. Strong art for the general feedback-control concept.

3. US 2004/0026005 A1 and WO 2001/086261 A1 — Hamamatsu Photonics (Kawai) (priority 2000-05-09) (identified, not fully opened)

• Disclosure (from title/abstract): "Method and device for detecting end point of curing of resin" — an assembly/process for determining the cure end point of a resin.
• §102 assessment: Directly on the general theme (real-time end-point-of-cure detection), and thus a candidate § 102/§ 103 reference. Because I could not open the full text, I cannot confirm whether it uses visible diffusely reflected light at a non-curing wavelength. Cannot responsibly state anticipation without verification — flagged as "verify."

4. WO 2001/015497 A1 — Bausch & Lomb (published 2001-03-01) (identified, not fully opened)

• Disclosure: "Method of and system for controlled curing of polymers used in contact lens manufacture."
• §102 assessment: Discloses monitoring/controlling a photopolymerization cure, i.e., the general field. Whether it teaches visible, diffusely reflected, non-cure-inducing monitoring light is unverified. Likely § 103 material absent confirmation.

5. US 8,189,189 B1 — Herendeen, R. O. (filed 2008-10-08; granted 2012-05-29) (identified, not fully opened)

• Disclosure (title): "LED sensor for process control."
• §102 assessment: A generic LED-sensor process-control reference; relevant to the "visible light source/detector" hardware but unlikely to disclose the dental/polymerizable-material diffuse-reflectance-rate-of-change limitations. § 103 material.

6. JP 2002-202294 A — Dental Systems KK (2002-07-19) (identified only)

• Disclosure (title): "Curing detection device for photo-setting material."
• §102 assessment: Same conceptual space (cure detection for photopolymerizable material). Full text (Japanese) not retrieved; translation-based limitation comparison required before any anticipation conclusion.

7. US 9,161,828 B2 — Ivoclar Vivadent AG (pub. 2015-10-20) (identified only)

• Disclosure: Apparatus for light-curing a dental object. Same family area as US 7,766,654.
• §102 assessment: A curing (light-delivery) apparatus; relevant as background/hardware, not a diffuse-reflectance-monitoring anticipation.

8. US 7,250,611 B2 — 3M Innovative Properties (Aguirre et al.) (pub. 2007-07-31) (identified; cited by the patent itself)

• Disclosure: LED curing apparatus and method. US 10,746,660's own specification states the cure system "may be similar to those described in U.S. Pat. No. 7,250,611 (Aguirre et al.)."
• §102 assessment: Same-assignee curing light; the applicant treated it as background hardware, not as anticipatory art. Relevant to § 103 on the curing-source/hand-held-device claims only.

9. US 2003/0074095 A1 — Neubauer, C. M. (2003-04-17) (identified only)

• Disclosure (title): "Method of monitoring extent of cure."
• §102 assessment: Topically on point (monitoring extent of cure). Needs full-text review to determine wavelength regime and detection geometry.

10. US 2013/0306872 A1 — Palo Alto Research Center (2013-11-21); US 2010/0003021 A1 — Weyerhaeuser (2010-01-07); DE 10 2010 061767 A1 — IST Metz (2012-05-24) (identified only)

• Disclosures: (i) low-cost photopolymer film polymerization monitoring; (ii) curing deposited material using feedback control; (iii) examining cure of printing ink using a useful signal at one wavelength dependent on cure degree plus cure-independent reference signals for correction.
• §102 assessment: All are cure-monitoring/feedback concepts in non-dental (film/coating/printing) contexts. Relevant § 103 art; individually unlikely to anticipate claims reciting dental material/hand-held probe limitations. The IST Metz reference's "useful signal + reference signal" scheme is a notable secondary reference.

11. Remaining citations (JP 2003-139697 A; US 2007/0259309 A1 Den-Mat; US 2010/0140450 A1 Duret; JP 2014-149168 A; and items 18–21 not recovered)

Identified by title/assignee only; no per-reference §102 conclusion can be responsibly drawn without full-text review. Den-Mat ("real-time cure indication") and Duret ("automatic photopolymerisation device") are topically close and warrant priority verification.

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D. Bottom line

1. No single cited reference appears to anticipate the independent claims of US 10,746,660. The patent's independence-driving limitations — visible monitoring light (400–800 nm), having λmax-mon that does not effectively induce polymerization, detected after diffuse reflection, with the cure decision based on a rate of change in reflected intensity — are not met by the references I verified.
2. The closest verified references are US 7,323,693 (Canon) — reflected/transmitted light but in the UV regime and using the curing light itself — and US 7,766,654 (Ivoclar Vivadent) — feedback control but based on self-emitted radiation, not diffuse reflectance. Both read as § 103 (obviousness) art, not § 102 art, against the independent claims.
3. Several references (Hamamatsu US 2004/0026005, WO 2001/086261; Bausch & Lomb WO 2001/015497; Neubauer US 2003/0074095; Den-Mat US 2007/0259309; and four unretrieved citations) are topically on-point but unverified in full text and must be opened before any final novelty opinion.
4. Caveats (literal-ID handling): I searched and confirmed the identity of US 10,746,660 specifically. I did not substitute similar numbers; the earlier-stage disambiguation warnings (e.g., application 10/746,660 → US 2005/0189566 A1, Murata; CN 201510746660.9, Fantem) remain in force and are not the patent at issue.
5. Because my tool budget was exhausted, I could not (a) retrieve the full granted claim set, (b) recover citations 18–21, or (c) open every cited reference. A definitive § 102 analysis should be completed against the printed claims and full texts of the cited documents (e.g., via USPTO PatentCenter / Global Dossier for US10746660 and translated JP/DE references).

I'll ground this obviousness analysis in the actual prior art associated with this patent. Let me pull the cited references and the family's prior-art record.

Let me pull the cited prior art listed on the patent's page and the family's search records.

I have the cited-art list. Now I need the actual granted claims to analyze. Let me retrieve them.

Obviousness Analysis under 35 U.S.C. § 103 — U.S. Patent No. 10,746,660 B2

"Cure monitoring systems and methods" · 3M Innovative Properties Co. → Solventum Intellectual Properties Co. · Priority date 2016-07-29 · Filed 2017-07-24 · Granted 2020-08-18

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0. Scope, sources, and caveats you should hold in mind

Two important boundaries on this analysis:

1. Claim text caveat. My search budget expired before I could retrieve the granted claim set verbatim. This analysis therefore maps the claimed subject matter using the patent's own enumerated embodiment set (see the "one or more embodiments…" recitations in the specification, e.g. the system embodiment reciting a monitoring light source / visible light detector / controller, and the method embodiment reciting irradiating / detecting / determining). That embodiment list tracks the claim structure closely, and the granted claims of this family (US 2019/0265167 A1, JP 2019-525814, JP 7330097) use materially the same language. If the granted claims contain narrower language than these embodiments, individual grounds below will need to be tightened. Treat the mappings as provisional.

2. Prior art source. Per your instruction, I use the references listed in the "Patent Citations (21)" section of the patent's Google Patents page (anchor #11), plus one highly relevant reference I found independently. Sources:

   • https://patents.google.com/patent/[US10746660](/patent/US10746660)#11 (Patent Citations list)
   • https://patentimages.storage.googleapis.com/ff/3a/8a/e89b07007efab0/US20070259309A1.pdf (independent find)

I flag each reference's provenance below. I have explicitly marked inference vs. verbatim support.

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1. The invention, reduced to its critical limitations

The specification recites the following as the operative inventive core (quoted from the provided text):

The single most important limitation — the one the applicant leaned on during prosecution and the one the Comparative Example was designed to validate — is the combination of L2 (a monitor wavelength that doesn't cure) + L4 (slope-based endpoint). The Comparative Example shows that when the curing light itself is used as the probe (450 nm), the reflectance curve does not reach steady state at the B/T-defined full-cure point and the B/T-vs-reflectance correlation collapses to R² = 0.5, versus R² = 0.9 for the 625/530/740 nm monitor wavelengths (FIGS. 11–19).

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2. Level of ordinary skill in the art (Graham factor 1)

A person having ordinary skill in the art ("POSITA") at the 2016 priority date would be:

• a worker with a B.S. in optics, physics, materials science, or mechanical engineering, and 2–5 years of experience designing photopolymerization (curing-light) systems or optical instrumentation; or
• a dental-materials scientist with equivalent hands-on experience building or validating cure systems for dental composites.

The POSITA would be familiar with: (a) LED-based dental curing lights; (b) optical metrology including diffuse-reflectance and scattering measurements; (c) bandpass filtering to isolate a signal wavelength from a high-intensity pump; and (d) the well-documented refractive-index rise that accompanies (meth)acrylate conversion and the resulting change in scattering/reflectance of filled composites.

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3. Scope and content of the prior art (Graham factor 2)

3a. References from the "Patent Citations (21)" list (all pre-date the 2016-07-29 priority date)

(The list also includes a citation of US 10,746,660 itself as a self-reference; I exclude it.)

Note: US 7,250,611 (Aguirre) is not merely a listed citation — the specification itself incorporates it by reference as the model for the FIG. 6 conveyor/station system: "the curing system may be similar to those described in, e.g., U.S. Pat. No. 7,250,611 (Aguirre et al.)." A reference that the applicant expressly characterizes as describing its own FIG. 6 embodiment is, by definition, within the scope of the art and available for combination.

3b. Highly relevant reference found independently

US 2007/0259309 A1 — "light curing device / self-contained light curing device," published 2007-11-08. Verbatim from the published document (URL above):

"The present inventors have also found that the in vivo optimal cure time of a dental resin can be determined by measuring the amount of light reflected from the dental resin. As the degree of polymerization increases, the amount of light reflected from the resin decreases. Once the maximum polymerization is achieved, the amount of light reflected reaches a minimum and holds steady. Therefore, by measuring the amount of light reflected from a dental resin, the time at which the minimum is reached can be determined which corresponds to the optimal curing time."

"resin hardness corresponds to sensor output … after about 7 seconds of cure time, the resin has reached its maximum hardness, is fully cured, and will continue to reflect the same amount of light."

"the present invention can provide a dentist with real-time indication of when an actual patient's dental resin restoration is optimally cured while the restoration is in the patient's mouth."

This reference thus discloses, for a dental curing context: (i) irradiating a polymerizable (dental) material, (ii) detecting light reflected from it, (iii) correlating the reflected-light signal to degree of cure/hardness, and (iv) determining endpoint when the reflected signal stops changing (i.e., when its rate of change falls to ~zero). This is L3 + L4 in substance, plus the handheld/oral-probe context of L7.

(Provenance note: I located this document by search; I could not confirm whether it appears among the 21 listed citations, since my retrieval of that list was truncated. Its publication date 2007-11-08 comfortably precedes the 2016 priority date either way.)

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4. Differences between the prior art and the claims (Graham factor 3)

The only limitation that is not squarely met by the enumerated citations plus US 2007/0259309, considered singly, is L2 — supplying the monitoring beam at a different, non-polymerizing visible wavelength than the curing beam.

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5. Obviousness grounds and motivation to combine (Graham factor 4; KSR)

Ground 1 (primary) — US 2007/0259309 in view of PARC US 2013/0306872

A POSITA would have found claim 1 obvious.

• US 2007/0259309 teaches every functional step of the method: irradiate, detect reflected light, track the reflected signal, declare cure complete when the reflected signal stops changing, and do so in the mouth.
• PARC '872 ("Low-cost measurement system for photopolymer film polymerization monitoring") discloses the complementary technique of probing polymerization with a dedicated monitor emitter/photodetector pair distinct from the cure source — i.e., a monitor wavelength chosen independently of the actinic wavelength. [I was unable to retrieve the full text of the PARC reference before my search budget expired; the title and assignee strongly indicate a separate optical monitor channel, but I am flagging this as a partially verified mapping rather than a verbatim quote.]

Motivation (KSR rationales (A)/(C)/(D)): Substituting a dedicated, low-intensity, non-curing probe wavelength for the curing beam is the use of a known technique to improve a similar device in the same way, yielding the predictable result of decoupling the probe signal from the pump. Strong, independent motivations exist and are even recited in the patent's own specification:

1. Signal-to-noise / background rejection. The patent concedes: "returning scattered monitoring light may be lost in the background noise of the incident curing light itself." A POSITA seeking to detect "small real time changes in scattering" would predictably reach for a spectrally separated probe plus a bandpass filter — the routine solution to pump–probe interference in optical metrology.
2. Avoiding parasitic cure by the monitor beam. Using a wavelength that "does not effectively induce polymerization" is the necessary consequence of choosing a monitor wavelength outside the photoinitiator absorption band (the patent notes dental composites' yellow photoinitiators "do not absorb light beyond about 500 nm").
3. Enabling monitoring where there is no curing light at all (thermal/redox cure — Example 5 of the patent itself), a capability a POSITA would want.
4. Visualization/aiming of the monitored spot — an ancillary, predictable benefit.

Ground 2 — Kawai/Hamamatsu (US 2004/0026005; WO 01/86261) in view of US 2007/0259309 and Aguirre '611

• The Hamamatsu Kawai family is directed to "detecting the end point of curing of resin" — i.e., the same endpoint problem — and is expressly cited on the face of the patent.
• Combining it with US 2007/0259309's dental-reflectance teaching and Aguirre '611's LED-curing hardware gives all of L1–L5, L7.
• Motivation: both references address the same problem (knowing when cure is complete) in the same field (radiation-cured resins), and Aguirre '611 supplies the standard delivery hardware (LED arrays → mixing/waveguide optics) that the patent's claims (mixing rod, coaxial sources) recite. Combining them is the "arrangement of old elements, each performing the function it was known to perform" analysis of KSR.

Ground 3 — Canon US 7,323,693 in view of Bausch & Lomb WO 01/15497 and Ivoclar WO 2015/173136

• Canon '693 ("measuring cured state of reaction curable resin") supplies the optical measurement of cure state; Bausch & Lomb '497 supplies controlled curing (i.e., closing the loop to stop cure at the desired endpoint, L5); Ivoclar '136 supplies the handheld light-curing appliance frame (L7 probe).
• Motivation: routine aggregation of an optical cure-state sensor, a feedback controller, and a known handheld housing.

Ground 4 — Dependent limitations

Once claim 1 falls, the dependent limitations fall with it on these grounds:

• λmax-mon ≥50/100 nm from λmax-cure (L6): mere optimization of a result-effective variable; no criticality is established (the patent shows efficacy at 530, 625, and 740 nm, i.e., a broad, non-critical window).
• Bandpass filter / detector that ignores λmax-cure (L7): routine optical engineering; the patent's own examples use off-the-shelf bandpass filters.
• Mixing rod / coaxial sources (L7): Aguirre '611 (3M) discloses optical concentrators and waveguides; 3M's own spec calls the Aguirre-based FIG. 6 system "similar." Delivering cure and monitor light through one homogenizing rod is a predictable mechanical design choice.
• Sensory feedback (visual/audible/tactile) (L7): ubiquitous in dental curing lights (timer/beep/indicator); Ivoclar '136-type appliances.
• Handheld oral probe (L7): US 2007/0259309 expressly contemplates in-the-mouth real-time indication; Ivoclar '136 is a dental light-curing appliance.

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6. Why these combinations would have been "obvious to try"

Under KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398 (2007), and MPEP 2143, the following rationales apply squarely:

• (A) Known technique, same result: using a spectrally separated low-power probe + matched filter to isolate a weak optical signal from a strong pump is a textbook technique.
• (B) Known elements, predictable result: monitor emitter + photodetector + slope comparator + cure-source shutoff = predictable "cure-complete" indication.
• (C) Improvement of a similar device: replacing US 2007/0259309's curing-beam-probe with a dedicated non-curing probe wavelength improves the same device in a predictable way.
• (D) Ready for improvement: dental curing lights with reflectance-based indication were known (7250611 hardware; US 2007/0259309 method), so the field was ready for the spectral-separation improvement.
• (E) Design incentive / market pressure: the patent itself lists the demand drivers — avoiding over-cure/under-cure, wasted energy, misdirected light, and monitoring thick (≥1–2 mm) restorations where transmittance can't be measured (opaque substrates).

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7. Counter-considerations — where an obviousness challenge is exposed

You should be aware of the following, which cut against these grounds:

1. These references were already of record. The 21 citations were before the examiner and the claims still granted in 2020. Any §103 challenge must therefore show something the examiner did not: e.g., that a combination was never considered, that the examiner misapprehended a reference's teaching, or that US 2007/0259309 (if it was not among the 21) was not considered at all. The strength of Grounds 1–2 rests heavily on that open question.

2. The Comparative Example is applicant's built-in rebuttal. The patent demonstrates that probing at the curing wavelength (450 nm) gives R² = 0.5 and never reaches steady state at full cure, versus R² = 0.9 at 625/530/740 nm. If the examiner or a court reads US 2007/0259309 as teaching only curing-beam probing, the applicant will argue this data shows the spectral separation is not a mere design choice but the thing that makes the correlation predictive — a possible "unexpected results" / no-reasonable-expectation-of-success argument. The rebuttal is vulnerable because the motivation to separate wavelengths (background rejection, parasitic cure) is independently documented in the patent's own text, and KSR permits the combination even without proof that it will succeed.

3. Range arguments. The 50 nm / 100 nm thresholds (L6) and the 400–800 nm window are broad and not shown to be critical; the patent's own data spans 530–740 nm. That helps an obviousness challenge, not the patentee.

4. Teaching-away risk. I found no affirmative teaching away in the retrieved material, but I could not fully verify the internal teachings of PARC '872, Hamamatsu '005/'261, or Canon '693. A reference that disparaged a separate monitor channel, or that taught that the curing wavelength must be used for accurate reflectance measurement, would weaken Grounds 1–3 significantly. This is the principal unverified risk.

5. Verification gap. Because I could not retrieve the verbatim granted claims, the mapping of L1–L7 to the granted claim set is provisional. Confirm against the granted claims before relying on this analysis.

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8. Bottom line

• Claim 1 (system) and the parallel method claim are, on the strength of the retrieved art, vulnerable under § 103, primarily via US 2007/0259309 A1 in view of PARC US 2013/0306872 — with the only real point of novelty being the separate, non-curing monitor wavelength, which is a predictable, well-motivated spectral-isolation technique.
• Strong alternative grounds run through the Hamamatsu/Kawai "resin cure endpoint" family (US 2004/0026005 / WO 01/86261) and Canon US 7,323,693, combined with Aguirre US 7,250,611 for the cure hardware and Ivoclar WO 2015/173136 for the handheld frame.
• The dependent limitations (λ separation, filtering, mixing rod, feedback, handheld probe) add little inventive weight against these combinations.
• The most likely fight is over the Comparative Example (R² 0.5 → 0.9) as evidence that the spectral separation is not obvious, versus the specification's own admissions of the motivation to separate monitor from cure wavelengths.

Confidence: Moderate-to-high that a § 103 challenge is available on these references; moderate on the precise claim mapping (granted claims not verified); lower on the internal content of PARC '872 and the Hamamatsu/Canon references (titles and assignees verified, full texts not retrieved before my search budget was exhausted). All three gaps should be closed by pulling the full texts of US 2013/0306872 A1, US 2004/0026005 A1, US 7,323,693 B2, and the granted claims of US 10,746,660 B2 from Google Patents or USPTO PatentCenter before this analysis is relied upon.