US 9464947

I'll run targeted searches for this specific patent number and for any litigation/docket activity.

Now let me check for litigation and CAFC docket activity, plus the USPTO status/assignment record.

US 9,464,947 — search summary

Caveat up front: I ran targeted searches for this exact number (USPO/Google Patents, Justia, FPO-style aggregators, and open-web queries aimed at CAFC 2026 dockets and district-court complaints). I found no CAFC 2026 docket and no litigation filing naming US 9,464,947. The only litigation-adjacent hit was an unrelated Delaware case (Aon Re, Inc. v. Zesty.ai, Inc., No. 25-201) that merely mentions a deponent named "Okazaki" — not related to this patent or this assignee. The Google Patents record carries a boilerplate "Family has litigation" Darts‑IP link, but I could not retrieve any case detail behind it, so treat that flag as unverified rather than as evidence of a suit. Everything below is grounded in the patent document and the bibliographic data returned in search.

Bibliographic data

I could not independently confirm live USPTO Patent Center status/fee data through search; the "Active / 2032‑10‑19 expiration" figures above come from the patent record I was given, and are assumptions, not legal conclusions.

Abstract (as granted)

A cryogenic temperature measuring resistor element comprising a metallic temperature measuring resistor wire, an electric insulator made of a polycrystalline ceramic material, and a filler filled between the insulator and the resistor wire. The filler comprises polycrystalline inorganic electric insulating powder whose particles are connected by glass. The glass has a softening point lower than the respective melting points of the insulating powder, the resistor wire, and the electric insulator.

Claims — plain language

Note a structurally important point: the granted claims are all method claims, six in total, with only one independent claim (claim 1). The apparatus claims that appeared in the pre‑grant publication US 2015/0211942 A1 (element comprising wire + housing + filler with glass‑bonded particles) do not survive in the issued patent. So for US 9,464,947 as granted, the "independent claim" overview is:

• Claim 1 — independent (method of producing the element). Steps: (1) provide a resistor wire and a housing to hold it; (2) mix polycrystalline inorganic electric insulating powder with amorphous glass powder whose softening point is lower than the melting temperatures of the powder, the wire, and the housing; (3) fill that mixture between the housing and the wire; (4) heat above the glass softening point but below the melting temperatures of the wire, housing, and powder so that only the glass melts; and (5) cool so the solidified glass bonds the insulating powder particles to one another. Plain‑language gist: you don't densify or sinter the ceramic — you use a low‑melting glass as a "glue" that welds the ceramic grains into a continuous heat path, without damaging the wire or housing.

• Claim 2 (dep. on 1). The resistor wire is a platinum–cobalt alloy and is coil‑shaped.

• Claim 3 (dep. on 2). The Pt–Co alloy contains 0.5 mol % cobalt, and the glass‑melting temperature is 460 °C to 520 °C and at least 50 °C above the glass softening point.

• Claim 4 (dep. on 3). The insulating powder is alumina; the glass is bismuth oxide as main component + zinc oxide + boron oxide; and the glass is 3.5 wt % to 10.0 wt % of the filler.

• Claim 5 (dep. on 1). Structural packaging limitations folded into the method: lead wires at opposite ends of the resistor wire; housing is a cylindrical electric insulator with two axial through holes; the wire is threaded through both holes with both ends exiting on the same side; the powder/glass mixture sits in the gap between the hole walls and the wire.

• Claim 6 (dep. on 5). The through‑hole end portions are sealed with an electric‑insulating sealer.

Technical problem and the asserted solution (context for the claims)

• The stated problem: with conventional elements (Pt–Co wire loose in polycrystalline insulating powder), below ~90 K the air in the powder voids liquefies and then solidifies, collapsing the gas‑phase heat path; Joule heating from the measurement current is then poorly dissipated and the wire reads too hot, producing a positive error that grows at low temperature and grows with measurement current (Table 1: at 4 K, +1.1 K at 0.2 mA, +4.1 K at 1 mA, +7.9 K at 2 mA).
• The asserted fix: melt only a low‑softening‑point glass mixed into the ceramic powder so the grains become glass‑bonded and retain thermal conductivity even when the residual gas is frozen out. Test 3 (7.7 wt % glass) reports errors of 0.0/+0.1/+0.1 K at 4 K, 8 K, 10 K across 0.2/1/2 mA (Table 4) — i.e., roughly 1 °C or better.
• Claim‑relevant test data: Test 1 (heating temperature) supports the 460–520 °C window of claim 3; Test 2 (mixing ratio) shows the value variation on going 0.2 mA → 2 mA drops to ≤0.1 K at ≥3.5 wt % glass, supporting claim 4's 3.5–10.0 wt % range (1.8 wt % was insufficient; higher ratios risk restraining the wire and adding thermal‑expansion error).

Verification limits

• I did not find any CAFC 2026 appeal or docket for this patent; absence of results is not proof that none exists, but I have no authoritative filing to cite.
• I could not confirm a litigation history beyond the unverified aggregator flag.
• The forward‑citation list (e.g., US 10,897,069 to IBM; later Okazaki/Chino/Endress+Hauser cryogenic sensor filings) indicates continuing technical relevance of the family, but I did not verify the legal effect of any of those references.

I'll search multiple litigation sources for US patent 9464947.

The Google Patents page flags "Family has litigation" for this patent family. Let me dig into specific litigation databases.

I'll verify the structured "no proceedings" signal against public sources before writing anything up.

Search 1 returned unrelated reexamination documents. Let me run more targeted queries.

No PTAB hits. Let me check the litigation signal (the patent page flags Darts-IP family litigation) and any CAFC activity.

Proceedings overview

Zero AIA trial proceedings are on file for US 9,464,947. The structured "PTAB proceedings on file" block — sourced from the USPTO Open Data Portal — returns no IPR, PGR, or CBM for this patent, and my independent searches of PTAB public filings and third-party PTAB trackers surfaced no petition, institution decision, or Final Written Decision naming the '947 patent. The bottom line for a defendant: there is no claims-invalidated shortcut and no estoppel to exploit — the patent stands un-challenged at the Board, all six claims remain live, and any invalidity fight must be built from scratch (at the district court under § 282, or by filing the first IPR yourself and living with a 12-month trial clock).

No per-proceeding entries follow, because there are no proceedings to describe. I am not going to manufacture docket numbers to fill the template.

What the record actually shows

Patent identity (verified against the full text):

• US 9,464,947 B2 — "Cryogenic temperature measuring resistor element"
• Applicant/assignee: Okazaki Manufacturing Company (Kobe, Japan)
• Appl. No. 13/982,700; PCT/JP2012/006718; filed 2012-10-19; granted 2016-10-11; anticipated expiration 2032-10-19
• Family: US13/982,700 / JP5216947B1 / WO2014061069A1
• 6 claims, all method claims ("A method for producing a cryogenic temperature measuring resistor element…") — claims 1–6. There are no apparatus claims in this patent.

Litigation flag — flagging, not characterizing. The Google Patents record for this family carries a Darts-IP litigation indicator: "Family has litigation — First worldwide family litigation filed." I could not identify the case, parties, venue, or filing date from public sources in this pass, and I expressly decline to guess. Two cautions for a defendant: (1) the flag is family-level and may attach to the JP or WO counterpart rather than the US patent; (2) family-level litigation is not evidence of PTAB activity. If you are facing a demand letter, pull the Darts-IP family report or PACER/JP docket directly rather than relying on the Google Patents banner.

Forward citations (relevant because they show who is watching this space, not because they are proceedings): IBM (US10897069B2), Auxitrol (FR3018604B1), Endress+Hauser (DE102017113768A1), Chino (JP2018091642A), Hayashi Denko (JP6934252B2), Yamari (JP7370604B2), Rosemount (US12578237B2). This is a crowded, commercially active cryogenic-sensor field — the absence of IPRs is a signal about litigation posture, not about the patent being unimportant.

Appeal check: No Federal Circuit appeal touching the '947 patent was identified. With no FWD, there is nothing to appeal from — an appeal requires a Board decision, which does not exist here.

Strategic summary

Claim status. All six claims are UNTESTED — not canceled, not sustained, simply never put at issue before the Board. Claims 1 and 5 are the independent method claims; claim 1 recites the core three-step process (mix inorganic insulating powder + glass powder → heat above the glass softening point but below the melting points of the wire/housing/powder → cool to bind the powder particles); claim 5 adds the two-through-hole cylindrical ceramic insulator architecture; claims 2, 3, 4, and 6 are dependent. Notably, claims 3 and 4 carry the narrow numerical limitations (0.5 mol% Co; 460–520 °C; ≥50 °C above softening point; glass at 3.5–10.0 wt%) that the specification's Test 1–Test 3 data were designed to support. Those numeric bounds are the patent's real strength and its vulnerability: claim 1, standing alone, is the broadest and least numerically anchored claim.

Estoppel landscape. There is no § 315(e)(2) estoppel, because estoppel attaches only to a petitioner that filed an IPR/PGR that reached a Final Written Decision. With no petitioners, no bars exist — for anyone. Every prior-art ground is available to a defendant or a would-be petitioner, with the sole substantive constraint being the 2012-10-19 effective filing date: art must qualify under § 102/§ 103 as of that date. A would-be IPR petitioner also faces the ordinary § 315(b) one-year bar running from service of an infringement complaint, if one is ever served.

Pattern signals.

• Repeat petitioner: None — no petitioner has ever filed on this patent, so there is no General Plastic / follow-on-petition exposure.
• Aggressive patent-owner appeals: None at the Federal Circuit. Okazaki is a 1954-founded, 277-employee operating manufacturer with ~50% Japanese domestic share in industrial temperature sensors — this is a practicing-entity patent portfolio, not an assertion vehicle, which is consistent with (though not proof of) the thin assertion record.
• Defensive aggregator: No Unified Patents, RPX, or similar involvement is visible on the record.
• Related-company filings: Okazaki itself filed JP6150971B1 ("Resistance thermometer sensor and manufacturing method thereof," 2017-02-10), showing continued in-house prosecution activity in the same technology — expect further related filings rather than more patents on this exact disclosure.

Recommended next steps

1. Do not plan around an invalidated claim — there isn't one. Any clearance or invalidity opinion must address all six claims, and claim 1 in particular, on their merits. There is no FWD to link to and no Board disposition to quote; be suspicious of any AI-generated summary that purports to quote one.
2. Exploit the method-claim structure. Because every claim is a method of producing claim, infringement requires proof that the defendant (or an entity within its control) actually performs the recited heating step at 460–520 °C with a glass powder meeting the claimed softening-point relationship. That creates (a) a divided-infringement / control defense if manufacture is outsourced, and (b) a detection problem for the patent owner, who must obtain the accused party's process temperatures and filler composition. Conversely, if you are the patent owner, your proof will live in discovery of the competitor's furnace logs and BOM.
3. If you intend to file the first IPR, budget for the full statutory track: petition → § 314(b) institution decision at 6 months → patent owner response, reply, and optional oral hearing → FWD at 12 months from institution (extendable to 18 for good cause). The three strongest art hooks are the numeric ranges in claims 3–4, the pre-existing Pt-Co resistor-wire art (JPS53-53758 and the Yokogawa Technical Report, both cited on the face of the '947 patent), and conventional glass-frit-bound ceramic/insulator art. Note that JPS53-53758 and JPS57-126035 were before the examiner — you will need art the examiner did not consider, or a materially different combination, to clear the Advanced Bionics hurdle.
4. Verify the litigation flag before doing anything else. Pull the Darts-IP family report (the link is embedded in the patent record) or the JP/US/UK dockets. If a real US case exists, the § 315(b) clock may already be running for a defendant named in it — and that, not any PTAB history, is your real timing constraint.

Caveats on my confidence: I have high confidence there are no AIA trial proceedings on US 9,464,947 (two independent sourcing paths agree, and the ODP is the canonical registry). I have low confidence on the identity and status of the flagged family litigation — that is an unresolved open item, not a finding.

I'll verify the assignment record and corporate status before writing. Let me run several searches.

Let me check for litigation records and the assignment center entry.

Ownership Analysis — US 9,464,947 B2 ("Cryogenic temperature measuring resistor element")

Data caveats up front (read before the timeline). I could not complete a live, authenticated query against USPTO Assignment Center (assignmentcenter.uspto.gov) in this session — my searches returned no assignment-cover-sheet PDF or reel/frame record for this patent number. The only assignment event visible to me is the one recorded in the Google Patents legal-events table reproduced in the authoritative patent text you supplied. I therefore cannot supply reel/frame numbers or a correspondent name for this patent, and I will not invent them. Everything below is grounded in (a) the authoritative patent text, (b) the Google Patents legal-events entries quoted in it, and (c) live web results on the assignee. Verify reel/frame directly at Assignment Center or assignment.uspto.gov by searching patent number 9464947.

Inventors

Pattern notes. All three inventors conveyed to the same operating company, consistent with a standard employee-invention assignment at a Japanese manufacturer. The application is a PCT national-phase entry (PCT/JP2012/006718, filed 2012-10-19) with no earlier priority claim — the PCT filing date is the priority date (2012-10-19). The inventors are listed in the same order on the JP family member JP5216947B1.

There is no evidence of inventor departure in any source I could reach, and no SEC or press coverage of these individuals (Okazaki is privately held, so no 10-K/8-K trail exists). I do not know their later employment — flagged as unknown rather than inferred.

Original assignee

Okazaki Manufacturing Company (listed on the face of the patent as "Okazaki Manufacturing Co Ltd"), HQ 3-1-3 Goko-dori, Chuo-ku, Kobe, Hyogo 651-0087, Japan.

• Primary line of business: manufacture and sale of (i) temperature sensors, (ii) industrial electric heaters, and (iii) mineral-insulated (MI) cables. Founded 26 Jan 1954; privately held; paid-in capital ¥86.5 M; 621 employees as of 31 Mar 2026 per the company's own overview page. President: Kazuhide Okazaki.
• Product embodying the claims — yes, clearly. Okazaki's own cryogenic product literature markets the CERACOIL platinum-cobalt resistance thermometer ("PATENTED," cryogenic assemblies accurate to 1.5 K) and explicitly cites Patent No. 5216947 (P5216947) — the JP family member of the patent at issue. The commercial device is a PtCo 100 Ω / 1000 Ω resistance thermometer rated 1.5 K–373 K, i.e., squarely within the 4 K–90 K cryogenic claim scope. Sources: Okazaki cryogenic sensor datasheet, Aerospace brochure.
• Current status: operating, not acquired, not dissolved, not in bankruptcy. Business has expanded into hydrogen/fuel-cell and marine temperature sensing (brochures from 2022–2024 and a Farnborough 2024 trade-show listing). Corporate history also records the 1980 acquisition of ARi Industries Inc. (US) and subsidiaries in Taiwan (1987) and the UK.

Assignment timeline

The record contains exactly one recorded conveyance. There are no post-issuance transfers.

• Executed date: not stated in any source I retrieved / recorded 2013-07-30 — Reel/Frame: not retrieved (see caveat above)
  • Conveyance: Assignment of Assignors' Interest ("ASSIGNMENT OF ASSIGNORS' INTEREST (SEE DOCUMENT FOR DETAILS)" per the Google Patents legal-events line)
  • Assignor: Koichi Ito; Takashi Mihara; Shinichiro Saraie (all three joint inventors)
  • Assignee: Okazaki Manufacturing Company
  • Correspondent: unclear — not retrieved. I could not pull the cover sheet, so I cannot name the recording attorney/firm, and per the instructions I will not infer a recurring correspondent from nothing.
  • Context: inventor-to-employer assignment of the entire right, title and interest, recorded roughly nine months after the 2012-10-19 PCT filing date; the registered assignee is the applicant itself, so this is a housekeeping record, not a transfer of control.

For completeness, the non-assignment legal events (same table) are: 2013-07-30 reassignment to OKAZAKI MANUFACTURING COMPANY; 2015-07-30 publication of US2015/0211942A1; 2016-10-11 grant of US9464947B2; status Active; anticipated expiration 2032-10-19.

No Assignment Center records beyond this single inventor-to-company entry were found. Under your stated rule this is itself a finding: the original assignee still owns the patent.

Timeline diagram

timeline
    title Ownership of US 9464947
    2012 : PCT filed by Okazaki Manufacturing
    2013 : Inventors assign rights to Okazaki
    2015 : US application published
    2016 : US patent issued

NPE / troll-pattern signals

One live flag I could not resolve — flagging it as unclear rather than as a finding. The Google Patents info box supplied in the patent text contains a "Family has litigation — First worldwide family litigation filed" field with a Darts-ip link (family=48778699). Google Patents renders this field inconsistently, and it is often a template artifact rather than proof of a filed case; my targeted litigation searches ("Okazaki Manufacturing" + infringement complaint / district court) returned nothing. I treat this as unclear — unverified. If it is genuine, it would be Okazaki (a product company) as plaintiff, which would move the analysis toward operating-company assertion rather than NPE conduct. It does not change any of the eight NPE signals above, all of which depend on the assignment chain, not on litigation.

Counter-signal worth noting: the patent is cited by later operating-company filings, including US10897069B2 (IBM, 2021) and US12578237B2 (Rosemount Inc., 2026), and sits in a family that third-party operating companies have been building on — JP6150971B1 (Okazaki, 2017), JP6934252B2 (Hayashi Denko, 2021) and JP7370604B2 (Yamari Industries, 2023). That is the footprint of a live technical field occupied by manufacturers, not of an aggregated assertion portfolio.

Verdict

Insufficient data — clean-chain variant (no NPE activity).

By the taxonomy's own definition, "Insufficient data" covers the case of "only the original assignment," which is exactly what the record shows: a single 2013-07-30 inventor-to-employer assignment to Okazaki Manufacturing Company and no post-issuance transfer. On the specific question asked, however, the answer is not ambiguous but negative: zero of the eight NPE signals are present. The patent remains with the same 1954-founded, 621-employee Japanese sensor manufacturer that filed it, and that company sells the claimed subject matter in commerce — the CERACOIL PtCo cryogenic thermometer, which its own datasheet marks with JP Patent 5216947, the family member of this patent. There is no shell entity, no known asserter, no chained LLC transfers, no bankruptcy, and no defensive-aggregator endpoint. The only unresolved items are mechanical (reel/frame and correspondent not retrievable in this session) and the ambiguous Google Patents "family has litigation" flag.

Verify at: USPTO Assignment Center — search patent 9464947; mirrored at assignment.uspto.gov/patent/index.html. Google Patents legal events for this patent: patents.google.com/patent/US9464947B2/en.

I'll research US patent 9464947 and its prior art citations. Let me start with targeted searches.

Let me search for the most technically relevant prior art references cited on this patent.

I've gathered sufficient information to produce the prior-art analysis. Note: one search step hit the tool limit, so I could not retrieve the full text of Japanese reference JPS57124221A directly; I flag that below where relevant.

Prior Art Analysis — US 9,464,947 B2

Cross-reference note: This builds on the previously generated litigation summary. One dating discrepancy to flag explicitly: the litigation section header states "Today's date: 2026-09-29," while this task states "Current Date: April 26, 2026." I do not treat either as affecting the substance below, but the two are inconsistent and should be reconciled in the final compiled document.

1. Verification of the Patent Number (USPTO / Google Patents authoritative text)

No auto-correction was applied to the identifier. The record for US 9,464,947 B2 is confirmed as follows:

The number and its associated identifiers are internally consistent across the patent text, the Google Patents family table, and the onscope record. No similar-number substitution was found, and nothing in the search results contradicts the authoritative patent text.

2. The controlling claim — what prior art must disclose

Claim 1 (independent; the only independent claim) is a method claim requiring, in combination:

1. providing a temperature measuring resistor wire and a housing for accommodating it;
2. preparing a mixture of polycrystalline inorganic electric insulating powder AND glass powder of an amorphous electric insulating material, the glass powder having a softening point lower than the melting temperatures of the powder, the wire, and the housing;
3. filling the mixture between housing and wire;
4. heating to melt ONLY the glass powder (temp above glass softening point, below the melting temps of wire, housing, and powder); and
5. cooling to solidify the melted glass to connect particles of the insulating powder with one another.

Dependent claims narrow: cl. 2 = Pt–Co wire, coil shape; cl. 3 = 0.5 mol% Co, melt temp 460–520 °C and ≥50 °C above glass softening point; cl. 4 = alumina powder + Bi₂O₃/ZnO/B₂O₃ glass + 3.5–10.0 wt% glass; cl. 5 = cylindrical electric-insulator housing with two axial through-holes, ends exposed on the same side; cl. 6 = through-hole ends sealed with an electric-insulating sealer.

Key analytical point: Because every claim is a method claim drawn to a specific ordered combination, single-reference §102 anticipation is difficult to establish. Most of the 28–29 cited references are better characterized as §103 obviousness evidence. I identify below the strongest §102 candidates and then handle the remainder as §103 combinations.

3. Most relevant prior art (highest anticipation risk)

3.1 US 3,477,058 A — Magnesia insulated heating elements and methods of production

• Full citation: US 3,477,058 A; filed 1968-02-01; published 1969-11-04; assignee Gen Electric.
• Related family member: US 4,280,932 (same disclosure lineage; the search surfaced this continuation/improvement text), which describes "a uniform mixture of granular magnesia and a minor but effective amount of a glass which has a glass transition temperature below about 700 °C," where "the glass is believed to bridge between particles of magnesium oxide." The filler may contain 0.1% to 10.0% glass, and the assembled element is "conditioned at an elevated temperature of about 1100 °C."
• Description: Sheathed tubular electric heating elements comprising a coiled resistance wire, compacted magnesia (polycrystalline) powder, and an outer jacket, with a glass additive melted in situ to bridge/bond the magnesia particles to improve thermal conductance while preserving electrical insulation.
• Anticipation assessment: The closest single reference to the core of claim 1. It discloses a coiled resistance wire (cf. claim 2's "coil shape"), polycrystalline magnesia powder (claim 1's inorganic electric insulating powder), and glass of lower transition/softening temperature that is heated in situ to bridge the powder particles while the magnesia and jacket remain solid (the "melt only the glass" step). Its 0.1–10.0% glass range overlaps claim 4's 3.5–10.0 wt%.
• Potentially anticipates: Claim 1 (if the examiner treats the "temperature measuring resistor element" preamble as non-limiting and the resistance wire as reading on the "temperature measuring resistor wire"), and by extension the glass-ratio aspect of claim 4.
• Critical caveat: It is drawn to a heating element, not a temperature-sensing element, and uses Cabal glass (CaO–B₂O₃–Al₂O₃) — the reference expressly avoids zinc oxide and lead oxide ("easily reducible oxides … should be avoided"). Claim 4 of '947 requires ZnO + B₂O₃ + Bi₂O₃. This distinction materially weakens a straight §102 case against claim 4 and pushes the analysis toward §103.

3.2 US 4,586,020 A — Sheathed resistance heater

• Full citation: US 4,586,020 A; filed 1981-05-18; published 1986-04-29; assignee Matsushita Electric Industrial Co., Ltd.
• Description: A sheathed resistance heater having a coil-like heating wire, a metal pipe, and an electrically insulating powder (electrofused magnesia, silica, or alumina) admixed with another powder, the pipe ends optionally sealed with glass 5 and a heat-resistant resin. The stated objective is improved insulation resistance/life via the powder admixture.
• Anticipation assessment: Discloses the structural genus of claim 1 (coiled wire + inorganic insulating powder in a housing + glass). However, its admixture is a metallic/metal-oxide powder (e.g., NiO, Ni), not an amorphous glass powder used to bond the insulating particles. It does not teach "heating to melt only the glass powder" so as to connect the insulating particles.
• Potentially anticipates: Structurally relevant to claim 5 (wire-in-housing, glass-sealed ends) but not claim 1's method steps. Best treated as §103 art.

3.3 US 4,280,932 / US 3,477,058 family (glass-bonded refractory powder filler)

Covered in §3.1. Its express teaching that glass bridges between MgO particles to raise thermal conductivity is the single most on-point disclosure of the functional heart of claim 1.

3.4 US 3,436,713 A — Cryogenic resistance temperature detector

• Full citation: US 3,436,713 A; filed 1966-11-02; published 1969-04-01; assignee Universal Oil Products Co.
• Description: A resistance temperature detector expressly for cryogenic use — directly on point for the claim 1 preamble ("cryogenic temperature measuring resistor element").
• Anticipation assessment: Strong on the field/purpose limitation but (on the record retrieved) does not disclose the glass-powder-bonded inorganic filler or the "melt only the glass" step. Does not anticipate claim 1; is §103/combinatorial art establishing the cryogenic RTD context.

4. Japanese prior art expressly identified as background (Patent Documents 1 and 2)

4.1 JPS 53-53758 A — Material for temperature detector elements (= "Patent Document 1")

• Full citation: JPS 53-53758 A; filed 1976-10-27; published 1978-05-16; assignee Kogyo Gijutsuin (Agency of Industrial Science & Technology). Also indexed as JPS 5353758 A.
• Description: The patent's own specification cites this as the source of the platinum–cobalt alloy temperature-detector material and notes the 0.05–2.0 mol% cobalt range (with 0.5 mol% preferred). See '947 text: "As illustrated in Patent Document 1, the cobalt content may be set between 0.05 mol % and 2.0 mol %."
• Potentially anticipates: Claim 2 and claim 3 — the Pt–Co wire and the 0.5 mol% Co limitation are disclosed here. Claim 3's 460–520 °C melt-temperature window is not disclosed, so anticipation of claim 3 as a whole fails.

4.2 JPS 57-126035 U — Temperature Measuring Resistor Element (= "Patent Document 2")

• Full citation: JPS 57-126035 U (Japanese Unexamined Utility Model); filed 1981-01-31; published 1982-08-06.
• Description: Per '947's background section, this document shows the cylindrical electric insulator with two longitudinal through-holes, coil-shaped resistor wire, inorganic-powder filler, and optional sealer ("as shown in FIG. 1A of Patent Document 2, the sealer is not provided…").
• Potentially anticipates: Claims 5 and 6 — the two-through-hole housing geometry, same-side lead exposure, and sealer structure are disclosed here. It does not disclose the glass-bonded filler, so claims 1–4 are unaffected.

Note on JPS 57-126035: The '947 specification labels this "Patent Document 2" and cites it for the sealer-optional structure. My direct retrieval of this utility-model publication was not completed within the tool budget; the characterization above relies on the '947 specification's own description of it, which is the authoritative source in the supplied text.

5. Additional cited references — role and anticipation status

(Dates, assignees, and titles above are taken verbatim from the "Citations (28/29)" table in the authoritative patent text; I have not auto-corrected any identifier.)

6. Claim-by-claim anticipation summary

7. Analyst conclusions and explicit uncertainties

1. No single retrieved reference anticipates all elements of claim 1. US 3,477,058 / US 4,280,932 is the strongest §102 candidate because it discloses glass-in-situ bonding of polycrystalline powder particles around a coiled resistance wire, but its heating-element purpose and its Cabal (CaO–B₂O₃) glass — which expressly excludes zinc oxide — distance it from claims 1 and 4.

2. The most likely invalidity theory is §103, combining (a) the glass-bonded refractory-powder filler art (US 3,477,058 / US 4,280,932; US 4,586,020) with (b) a cryogenic resistance-thermometer reference (US 3,436,713; US 5,139,858; JPS 57-124221), and (c) the applicant's own Pt–Co and housing disclosures (JPS 53-53758; JPS 57-126035).

3. Highest-value features for the patentee (i.e., least anticipated) are the numerical limitations of claim 3 (0.5 mol% Co; 460–520 °C; ≥50 °C above softening point) and the claim 4 glass chemistry (Bi₂O₃ main component + ZnO + B₂O₃; 3.5–10.0 wt%) — consistent with the Test 1 and Test 2 data (Tables 2–3, FIGS. 3–5) showing the error minimum at ~503 °C and the error floor at ≥3.5 wt%.

4. Explicitly unresolved / requiring direct verification (I do not have high confidence here and will not fabricate):

   • The full disclosure of JPS 57-124221 A — its title ("…cryogenic thermometer and its production") makes it a potentially significant §102 reference, but I could not retrieve its body text within the tool budget.
   • The effective prior-art dates of US 2014/0321508 A1 (2014) and US 9,153,366 B2 (2015): both published after '947's 2012-10-19 priority date and therefore are not prior art to '947 absent an earlier effective filing date; if the final document lists them as "prior art," that listing should be corrected or qualified.
   • US 3,367,765 A ("Method of controlling the growth of noxious plants") appears facially irrelevant to cryogenic thermometry and is likely a citation-listing artifact; I flag it rather than assume its relevance.

5. No identifier corrections were applied, and no search result contradicted the authoritative patent text for US 9,464,947 B2.

I'll ground the analysis in the actual cited references before drawing obviousness conclusions. Let me verify the disclosures of the most probative prior-art citations on the page.

Significant finding on the glass-bonded filler concept. Let me verify the closest structural and glass-bonding references cited on the page.

Obviousness Analysis — US 9,464,947 B2 under 35 U.S.C. § 103

Scope note / flags before the analysis

• This builds on the claim construction and bibliographic sections already produced. As established there, all six granted claims are method claims and independent claim 1 is a method of producing the element. That matters for § 103: the question is not "was the glass-bonded cryogenic RTD known?" but "was the process of glass-bonding a powder filler in a cryogenic RTD obvious?"
• I used the Citations (28/29) and Family Cites Families (2) listed in the Prior Art section of the page as the universe of references, and augmented with targeted verification searches. Two verification cautions: (i) searching US 3,477,058 A surfaced material from its sibling GE patent US 4,280,932, which is not literally on the page's citation list but is the far more on-point disclosure (glass bridging magnesia particles). I treat it as a related reference and say so explicitly rather than pretending it is a cited document. (ii) I could not retrieve the body of JPS 57-124221 A (only its citation listing), so its disclosure is characterized from its title and citation position, not verified text.
• Minor housekeeping: the task header says "Current Date: April 26, 2026" while the environment date is 2026-09-29. Nothing in this analysis turns on that difference.

1. The claim set to be tested

The only genuinely novel-seeming subject matter is the process insight of claim 1 — use a low-softening glass as a "glue" that welds a loose ceramic powder into a persistent solid conduction path — plus the numerical/chemical refinements of claims 3–4. Everything else (Pt–Co wire, coil, two-hole ceramic body, sealer) is admitted prior art in the specification itself.

2. The prior art, grouped by the element it supplies

Group A — Pt–Co wire and its strain sensitivity (supplies claim 2; supports claim 3)

• JPS 53-53758 A ("Material for temperature detector elements," Agency of Industrial Science & Technology, pub. 1978-05-16) — cited as Patent Document 1; the specification states it discloses Pt–Co detector material with Co content settable between 0.05 and 2.0 mol %. This brackets the claimed 0.5 mol %.
• Non-Patent Document 1 — Yokogawa Technical Report (1988) Vol. 32 No. 3, pp. 29–32, "Interchangeable Pt–Co Cryogenic Temperature Measuring Resistor." The specification relies on this for the proposition that the resistance of Pt–Co varies with internal strain, i.e., that anneal history changes the reading.

Group B — The conventional cryogenic RTD architecture (supplies the "prepare wire + housing," "fill," and all of claim 5; claim 6)

• JPS 57-126035 U — cited as Patent Document 2; the specification describes it as the conventional element: coil wire in two longitudinal through-holes of a cylindrical ceramic insulator, powder filler, sealer sealing the through-hole ends (and explicitly notes a sealer-less variant in its FIG. 1A).
• JPS 61-202129 A ("Thermometer resistor / 測温抵抗体," Okazaki Seisakusho, pub. 1986-09-06) — same assignee's own earlier cryogenic RTD patent. It teaches coating a thin Pt resistance wire with glass or ceramic of matched coefficient of expansion and firing it ("さらに…ガラスあるいはセラミックをコーティングし、焼成して"), expressly to avoid mechanical stress and wire breakage from expansion mismatch. Same-assignee art is fully available for § 103.
• JPS 57-124221 A ("Temperature sensitive resistance element of cryogenic thermometer and its production," Japan Atomic Energy Research Institute, pub. 1982-08-03) — a cryogenic thermometer resistance element and a method of producing it. (Characterized from title/citation only.)
• US 3,436,713 A ("Cryogenic resistance temperature detector," Universal Oil Products, 1969-04-01) — a cryogenic RTD in which the sensor is mounted on a refractory glass support and embedded under a glass cement coat that is devitrified by heating (Pyroceram-type, fired to about 800 °F ≈ 427 °C) into a "substantially devitrified, crystalline and non-hygroscopic covering." Expressly motivated by eliminating strain-gage-type errors via matched expansion, and by avoiding porous/hygroscopic ceramic supports that break down when cryogenic fluid freezes in their pores.
• US 3,236,460 A (Malaker Labs, 1966) and US 3,412,359 A (Gen Motors, 1968) — early low-temperature/probe assemblies; general field evidence.

Group C — Particulate ceramic insulation in a wire-in-sheath structure, and its thermal conductance (supplies claim 1's "housing + powder + fill" and the thermal-conductivity rationale)

• US 3,477,058 A ("Magnesia insulated heating elements and methods of production," Gen Electric, 1969-11-04) — coiled resistance wire in compacted polycrystalline magnesia inside a sheath; the patent is expressly about raising the thermal conductance of the particulate insulation and, in the sibling US 4,280,932, about the interfacial heat-transfer barrier.
• US 4,586,020 A (Matsushita, "Sheathed resistance heater," 1986) and US 7,026,909 B2 (Rosemount Aerospace, "Housing for temperature sensing assemblies," 2006) — the sheath/powder-fill packaging in the heater and sensor arts respectively.

Group D — Glass-bonding ceramic powder to raise thermal conductivity (the crux of claim 1)

• US 4,280,932 (Gen Electric, "Magnesia insulated heating elements") — the single most probative reference. It discloses a filler of granular magnesia plus a minor amount (0.1–10 wt %, preferably 0.25–2 wt %) of a glass having a glass-transition temperature below about 700 °C, where the glass is "believed to bridge between particles of magnesium oxide so as to reduce the barrier to heat transfer normally present at such interfaces." That is claim 1's mechanism stated in terms.
• US 3,477,058 A — the same GE family; layer-structure particulate additives to magnesia that "increase the compaction density and the thermal conductivity of the magnesia insulation."
• US 2003/0220185 A1 (Sakamoto / Murata, pub. 2003-11-27) — a glass-ceramic of ceramic powder (TiO₂, CaTiSiO₅) plus 15–50 wt % glass, the glass being SiO₂–B₂O₃–ZnO (with an optional alkaline-earth oxide), fireable at ≤ ~1000 °C. Supplies both the "ceramic powder consolidated by a low-melting boron-zinc glass" concept and a boron-zinc glass chemistry overlapping claim 4's (minus Bi₂O₃).
• US 2008/0222965 A1 (Saint-Gobain Abrasives) — vitrified (glass) bonded ceramic-grain body; shows the generic nature of glass-bonding refractory particulates.
• JPH 10-303004 A (Mitsubishi Materials, "Thermistor element and manufacturing method," pub. 1998-11-13) and JPS 54-118284 A (Kitamura, "Vibration-proof high-temperature measuring resistor and making method," pub. 1979-09-13) — in-family evidence of glass-bonded/glass-encapsulated temperature-sensing elements and their methods.

3. Level of ordinary skill

A designer of record with a mechanical/materials or ceramics background and several years in temperature-sensor or sheathed-element manufacture, familiar with (a) Pt and Pt–Co resistance thermometry, (b) powder-filled sheathed sensor/ heater construction, and (c) the standard ceramic-processing toolbox — including low-melting sealing glasses — available in the relevant literature. The patent's own specification treats all of (a), (b) and (c) as within the ordinary artisan's knowledge, which supports a relatively high skill level and correspondingly lowers the § 103 threshold.

4. The combinations, and why the artisan would have made them

Combination I (primary) — Conventional cryogenic RTD structure + Pt–Co wire + glass-bonded powder filler

JPS 57-124221 A (or JPS 57-126035 U) + JPS 53-53758 A + US 3,477,058 A / US 4,280,932.

Motivation. All references are in the same field of endeavor (temperature sensing / sheathed insulated electrical components) and address the same physical problem — heat transfer through a mass of loose refractory powder. US 4,280,932 supplies an express, articulated reason to glass-bond: the interfacial barrier between powder grains limits conduction, and glass bridging removes it. A POSITA confronting a cryogenic RTD whose reading drifts positive (i.e., the resistor is hotter than its surroundings because heat cannot escape) has a direct, KSR-sanctioned motivation to substitute the known glass-bonded filler for the plain powder filler to restore the conduction path — a predictable use of a known technique to improve a known device, exactly the KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398 (2007) rationales of "known technique, known problem, predictable result." The result — better heat dissipation, hence less self-heating error — is the very result US 4,280,932 promises.

Combination II — Cryogenic RTD + glass directly, from a cryogenic-specific reference

US 3,436,713 A + JPS 57-126035 U (or JPS 61-202129 A).

US 3,436,713 A is already a cryogenic RTD using glass (a refractory glass support plus a devitrified glass cement coating) fired at ~800 °F (≈427 °C) to hold and thermally couple a noble-metal sensor, and it expressly frames the goals as (i) eliminating strain-gage errors via expansion matching and (ii) replacing porous, hygroscopic ceramic supports that fail when cryogenic fluid freezes inside them. Combining it with the through-hole powder-fill architecture (Patent Document 2) yields every step of claim 1: mixing a ceramic powder with a glass-forming component, filling, heating to fuse the glass only, and cooling to a devitrified/bonded solid. JPS 61-202129 A — the assignee's own prior patent — independently teaches coating a cryogenic Pt wire with glass and firing it, so the assignee was on record years earlier that firing glass in intimacy with a cryogenic Pt element was acceptable practice. This alone is a strong § 103 case, and is aggravated by the fact that the assignee's own earlier teachings would have pointed toward the claimed route.

Combination III — Low-melting glass-ceramic chemistry and ratio (for claim 4)

US 2003/0220185 A1 (+ US 4,280,932; + JPS 53-53758 A).

• Claim 4's alumina powder is the admitted conventional filler material in the patent's own Background.
• Claim 4's B₂O₃–ZnO glass components are the glass system of US 2003/0220185 A1 (SiO₂–B₂O₃–ZnO, fireable ≤1000 °C); Bi₂O₃ is the familiar low-softening/lead-free sealing-oxide of the glass art (see § 6 caveat) and its role — depressing the softening point below ~405 °C — is ordinary.
• Claim 4's 3.5–10.0 wt % bracket sits inside US 4,280,932's disclosed 0.1–10 wt % and below US 2003/0220185 A1's 15–50 wt %; selecting a working sub-range between these is routine optimization of a result-effective variable (In re Boesch; KSR).

Combination IV — For claim 3's numerical window

JPS 53-53758 A / Non-Patent Document 1 + US 4,280,932 / US 3,436,713 A.
Given (i) JPS 53-53758 A's 0.05–2.0 mol % Co range and (ii) Non-Patent Document 1's teaching that Pt–Co resistance depends on internal strain, a POSITA would recognize the glass-melt/anneal temperature as a result-effective variable and would bracket it by routine testing between the glass softening point (must melt) and the temperature at which the Pt–Co anneal degrades the reading (must not over-anneal). That is precisely the optimization the patent describes, and KSR makes such optimization obvious absent unexpected results.

5. Element-by-element / claim-by-claim conclusion

6. Counterarguments the patentee will raise (and the weaknesses in each)

A defensible § 103 opinion must state where the prima facie case is softest.

1. The specific Bi₂O₃–ZnO–B₂O₃ glass (claim 4). The closest cited glass references use CaO–B₂O₃–Al₂O₃ (Cabal, US 4,280,932) and SiO₂–B₂O₃–ZnO (US 2003/0220185 A1) — neither is Bi₂O₃-based. If the record contains no reference to a bismuthate low-softening sealing glass, the patentee can argue the 405 °C, lead-free, bismuthate glass is a non-obvious selection. My verification was incomplete on this point and I will not assert the opposite. The examiner's (and the challenger's) counter is that bismuth-oxide-based low-melting, lead-free sealing glasses were a well-known commercial class by 2012, making the selection obvious as a matter of common knowledge — but that argument needs a supporting reference or declaration, which the page's citation list does not appear to provide.

2. Teaching away — US 4,280,932 disparages ZnO (and lead oxide). That reference states the filler "should be substantially free of conductive materials such as iron, alkalis, and/or easily reducible oxides such as lead oxide and zinc oxide. Reducible oxides should be avoided since oxygen pressures of below about 10⁻¹⁵ atmos. can occur." Since the invention's glass uses ZnO, this is the patentee's best teaching-away argument. Rebuttal: the reference's rationale is expressly tied to the high-temperature reducing environment of a sheathed heater operating at 750–1100 °C (oxygen partial pressures of 10⁻¹⁵ atm are simply not present in a 4–90 K sensor), so a POSITA would not carry the caution into a cryogenic sensor; and the reference's own preferred firing ("conditioned at an elevated temperature of about 1100 °C") is far above claim 3's 460–520 °C, so it is not even a same-purpose teaching against the claimed window. Teaching-away arguments fail unless the reference's criticism is directed at the claimed subject matter (In re Fulton).

3. Criticality of the 460–520 °C window (claim 3). The patentee will point to Tables 2–3 / FIGS. 3–5: outside the window the error exceeds ~1 °C, and at 1.8 wt % glass (below the claim 4 range) the error grows to +0.33/+0.48 K on the 0.2→2 mA step. This is a "critical range" argument. Rebuttal: the data show a smooth optimum — a classic result-effective-variable optimization — not an unexpected cliff; and the mechanism (glass must melt; Pt–Co must not over-anneal) was already known from Non-Patent Document 1. KSR and In re Applied Materials make broad-range selection with a discovered optimum presumptively obvious.

4. Secondary considerations. A long-felt but unsolved need arguably exists — the positive-error-at-cryogenic-temperature problem is documented in the field from the 1960s–1980s (US 3,436,713 A; JPS 57-124221 A) and the patent presents a dramatic improvement (Table 1: +7.9 K at 4 K/2 mA → Table 4: +0.1 K). That narrative supports nonobviousness. But the same factors cut the other way: the solution is the textbook "known technique applied to a known problem" (the glass-bridging disclosure of US 4,280,932 says the result is the expected one), and a long-felt need satisfied by an available known technique is ordinarily obvious.

5. The method-vs.-structure wrinkle. Because the claims are process claims, a challenger need only show the steps were known or obvious, not that anyone had previously made this exact device. The near-complete structural overlap with JPS 57-126035 U / JPS 61-202129 A and the near-complete process overlap with US 4,280,932 / US 3,436,713 A make that an unusually low bar.

7. Bottom line

• Strongest prima facie § 103 case (all claims): JPS 57-126035 U (or JPS 57-124221 A) in view of US 4,280,932 (glass bridging ceramic particles to cut interfacial thermal resistance), further in view of JPS 53-53758 A / Non-Patent Document 1 (Pt–Co wire and its strain sensitivity), and US 3,477,058 A (raising thermal conductance of the powder fill). Motivation: same field, same problem (heat transfer through loose refractory powder / self-heating of a resistance element), express statement of the result, and the KSR "known technique, known problem, predictable result" rationale.
• Independent, stronger-on-the-record alternative: US 3,436,713 A (a cryogenic RTD that already fires a glass cement to a devitrified solid and expressly seeks to avoid strain and porous-ceramic problems) in view of JPS 57-126035 U (through-hole powder-fill architecture with sealer) — this combination speaks to the cryogenic application directly and is not merely analogous art.
• Aggravating factor: JPS 61-202129 A is the assignee's own prior cryogenic RTD in which a Pt wire is glass-coated and fired. The assignee's own earlier teachings therefore point toward the claimed route, which weakens any "unexpected/discovery" narrative.
• Where the patent has its best (but not certain) defense: the Bi₂O₃-dominant, ZnO-containing, 405 °C lead-free glass of claim 4, both because no verified reference on the page discloses a bismuthate sealing glass and because US 4,280,932 affirmatively cautions against ZnO. That defense is narrow — it protects, at most, a dependent-claim-bestowed scope and does not rescue independent claim 1.

Verification limits: I confirmed the disclosures of US 3,477,058 A, US 4,280,932, US 3,436,713 A, US 2003/0220185 A1, and JPS 61-202129 A from primary text. I could not retrieve the body of JPS 57-124221 A, and I did not exhaustively verify whether any reference on the page discloses a Bi₂O₃-based sealing glass; both points are flagged rather than assumed. No search result contradicted the patent's own recitation of its prior art.