US 10190902

I'll search for authoritative information on this patent, including any litigation activity.

Let me verify litigation status and the related patent family more specifically.

US Patent 10,190,902 B2 — Summary

Caveat up front: I searched for litigation/docket activity (including 2026 CAFC dockets) and found no evidence that US 10,190,902 has ever been asserted in district court or appealed to the Federal Circuit. My searches returned no docket entries, complaints, IPRs, or CAFC opinions naming this patent. Because docket databases are not fully indexed by general web search, treat the "no litigation found" conclusion as uncertain rather than definitive.

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Bibliographic data

Related family note (flagged, not corrected): The description states there are no parent applications but references a co-pending application by the same inventor "with filing date: Feb. 17, 2016 and Ser. No. 14/998,8785." Taken literally, that serial number is malformed (nine digits after "14/"). The corresponding real application appears to be Ser. No. 14/998,785, which issued as US 9,765,978 B2 ("Low water sensor testing device," filed 2016-02-17, granted 2017-09-19, also Craig W. Billings). US 9,765,978 appears in the Google Patents "Similar Documents" list for the '902 patent but is not listed among its 25 cited references. I am flagging this rather than resolving it because the patent text literally recites "14/998,8785."

Abstract (verbatim)

"A low water sensor testing apparatus consisting of a 2 piece threaded steel ball valve unit with spring loaded handle connected at one end cavity portion thereof to initial piping emanating from a hot water boiler and connected at the second end cavity portion thereof to an equivalent adapter unit in turn connected to the first end segment of an E-shaped piping unit having its first stem portion connected to a ball valve unit via another adapter unit, its second stem portion connected via yet another adapter unit to a low water sensor unit and, with the second end segment of the E-shaped piping unit being connected to another equivalent adapter unit in turn connected to the first end cavity portion of a three way purge valve unit being connectable within the second cavity end portion thereof to outflow piping leading to a structure's heating system."

Problem addressed

Low-water cutoff sensors on hot-water boilers must be periodically tested. Per the specification, the conventional method requires draining the entire building water system to trip the sensor, then refilling it — described as time-consuming, expensive, and requiring two persons (one a master plumber). The patent claims a valved bypass manifold that lets a single person quickly isolate the sensor, drain only the small manifold volume, observe whether the sensor alarms, replace/repair the sensor if needed, and restore flow in minutes.

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Independent claims — plain-language overview

There are six independent claims: 1, 7, 13, 19, 25, and 27 (dependent claims: 2–6, 8–12, 14–18, 20–24, 26, 28).

Claim 1 — Full assembly, "iron/commercial piping" variant (direct threaded connection).
A low-water sensor test apparatus combining:

• (a–b) a 2-piece threaded steel ball valve unit with a spring-return handle, having internally threaded first and second end cavities;
• (c–d) a first hollow main connector adapter (externally threaded first end, unthreaded second end);
• (e–h) an "E-shaped piping unit": an elongated hollow body with two through-holes on a common axis, plus two stem portions ("E" shape);
• (i–j) a second identical main connector adapter;
• (k–l) a first small hollow adapter feeding a small ball valve unit (internally threaded inlet cavity, externally threaded outlet cavity, handle);
• (m) a second small hollow adapter whose internally threaded second end holds the low-water sensor unit by its external body threads;
• (n) a three-way purge ball valve unit with five cavity portions (internally threaded 1st, 2nd, 3rd, 5th; externally threaded 4th) and two handles (main + ancillary);
• (o–x) the interconnections: adapter→ball-valve-unit→soldered to body end; both stems soldered to the body at the through-holes; stem outer ends soldered into the small adapters; small ball valve threaded to the first small adapter; sensor adapter holds the sensor; the second body end soldered to the second main adapter, which threads into the three-way purge valve;
• (y–z) environmental connectability: the spring-return valve's first cavity is amenable to threading onto the externally threaded distal end of initial piping from a boiler in a commercial building; the purge valve's second cavity is amenable to threading onto the externally threaded proximal end of outflow piping to the heating system.

Claim 7 — Same as claim 1, but "copper/residential piping" variant.
Identical structure through element (x); the difference is in (y)–(z): the spring-return valve's inlet and the purge valve's outlet are instead amenable to receiving the threaded ends of additional hollow adapter units, whose other ends are soldered to unthreaded copper initial/outflow piping. (Substantively the same apparatus; the differentiation is the mode of field connection.)

Claim 13 — E-shaped unit soldered directly into both valves (no main connector adapters).
Drops the two main connector adapters. The E-shaped piping unit's first body end is soldered directly into the second cavity of the 2-piece spring-return ball valve unit, and its second body end is soldered directly into the first cavity of the three-way purge valve unit. Small adapters, small ball valve, and sensor adapter arrangement are the same as claim 1; (s)–(t) recite direct threaded connection to iron boiler/outflow piping. The specification describes this as the "most elemental embodiment," noting soldering can be used with non-threaded variants of the valves.

Claim 19 — Same as claim 13, but with solder-on adapters for copper piping.
Direct-soldered E-shaped unit as in claim 13, but (s)–(t) are the copper-piping variant: the valves' free cavities receive hollow adapter units whose other ends are soldered to the initial and outflow piping.

Claim 25 — Sub-combination: adapter / E-shaped / sensor side assembly.
Does not positively recite the 2-piece spring-return ball valve unit or the three-way purge valve as owned elements. Instead it claims the E-shaped piping unit plus: first and second main connector adapters, first and second small adapters, the small ball valve unit, and the sensor-mounting arrangement — with (l) the first main adapter "threadably connected within an internally threaded second end cavity portion of a 2 piece threaded ball valve unit with spring return" and (u) the second main adapter "threadably connected within an internally threaded first end cavity portion of a three way purge ball valve unit." In effect, a replacement/manifold sub-assembly that mates with those two valves.

Claim 27 — Narrowest sub-combination ("elemental" kit).
Recites only: the E-shaped piping unit (body + two holes + two stems), the first small adapter, the small ball valve unit, the second (sensor) small adapter, with the stems soldered to the body, the first small adapter threaded to the small ball valve, the sensor adapter holding the sensor by its threads, and — recited in amenability terms — the body's first end "amenable to being soldered to and within a second end cavity portion of a 2 piece threaded steel ball valve unit with spring return," and the body's second end "amenable to being soldered to and within a first end cavity portion of a three way purge ball valve unit." No main connector adapters, no drain caps, no valves as owned elements.

Representative dependent claims

• Claims 2, 8, 14, 20, 26, 28: internally threaded first drain cap threaded onto the small ball valve's externally threaded second cavity.
• Claims 3, 9, 15, 21: externally threaded drain cap receivable in the three-way purge valve's threaded fifth end cavity.
• Claims 4/10/16/22, 5/11/17/23, 6/12/18/24: the three valves are specified as APOLLO® part numbers 71-506-08 (2-piece spring-return steel ball valve), 70-103-HC (small ball valve), and 77B-106-01 (three-way purge ball valve).

Notable internal inconsistencies (flagged, not corrected)

• Claim 1(b) recites an "internally threaded second cavity portion," while 1(o) refers to the "second end cavity portion" — the numbering varies across the claim set.
• Claim 3/9/15/21 call for an "externally threaded drain cap component" received in the purge valve's threaded fifth end cavity, but the specification describes drain cap 39 as an "internally threaded drain cap component" rethreaded into that internally threaded fifth cavity. The claim language and the specification appear to conflict here.
• The specification states the coupling of fluid lines is by soldering (and describes iron piping diameters as "larger then" copper), and repeatedly describes the spring-return handle defaulting to the open position, which the patent frames as the safety feature.

Sources

• Google Patents full text: https://patents.google.com/patent/US10190902/en
• Justia Patents (claims text): https://patents.justia.com/patent/10190902
• RPX Insight: https://insight.rpxcorp.com/patent/[US10190902B2](/patent/US10190902B2)
• Related: US 9,765,978 B2 (Low water sensor testing device) — https://patents.google.com/patent/US9765978

Confidence: High on bibliographic data, claim structure, and claim interpretation (grounded in the authoritative full text). Low/uncertain on litigation status — no district-court, PTAB, or CAFC activity for this patent was found, but that is a negative search result, not a verified "no litigation exists."

I'll search for litigation involving US patent 10190902.

Let me search more specific litigation databases.

Let me run additional targeted searches to be thorough.

Summary of Search Results

No litigation involving U.S. Patent No. 10,190,902 has been identified.

What I searched

I searched for the specific number 10190902 across patent-litigation-relevant sources, including Unified Patents' litigation/PTAB portal content, Justia federal docket and CAFC materials, Docket Alarm, and general web/patent-database searches, plus searches combining the number with the patent owner's name (Craig W. Billings) and the patent title ("Low water sensor testing apparatus").

Why I could not confirm any case

• The only literal matches on the string "10190902" surfaced were false positives — e.g., a Brazilian state commercial-registry filing (JUCISRS) listing an unrelated registration number "10190902" for a company called FACTUAL PARTICIPACOES LTDA. That is not a patent case and does not involve US 10,190,902.
• Searches combining the patent number with litigation terms returned no district-court, ITC, or PTAB/PGR/IPR proceedings naming US 10,190,902.
• Notably, the patent number string does not appear in the returned CAFC decisions, which instead involved unrelated patents and parties (e.g., VL Collective IP v. Unified Patents, Nos. 24-1890; Ideahub v. Unified Patents, No. 24-1684; Dolby v. Unified Patents). None of these concern the '902 patent.
• The patent's own public record (as captured above) lists 25 cited references and one "family citing" document (CN110375370B), but no litigation events. Its current assignee is an individual (Craig W. Billings), and it is a sole-member family (US 15/530,632 → US 2018/0224320 A1 → US 10,190,902 B2).

Important caveats (be explicit about confidence)

1. No litigation found ≠ no litigation exists. Litigation searches are only as good as the databases queried. I was working from web search results, not a direct, authenticated query into Docket Navigator, Lex Machina, PACER, or the Unified Patents litigation caselist itself (I could not directly retrieve caselist records for this number). A negative finding here is provisional.
2. Do not treat this as legal conclusion. Before relying on it (e.g., for a freedom-to-operate or validity opinion), you should confirm by running the number directly against:
   • PACER / Justia Dockets (all federal district courts),
   • Unified Patents Portal – Litigation caselist (https://portal.unifiedpatents.com/litigation/caselist) and PTAB caselist,
   • Docket Alarm / Lex Machina / Docket Navigator, and
   • USPTO PTAB (to catch any IPR/PGR).
3. Related patent caution. The specification references a related application by the same inventor, Ser. No. 14/998,8785 (filing date Feb. 17, 2016), which corresponds to US 9,765,978 B2, "Low water sensor testing device" (also Craig W. Billings). If you are assessing the enforcement history of this inventor's low-water-sensor family, you should search litigation for US 9,765,978 separately — assertions (if any) may have been brought under that earlier patent rather than under the '902 patent. My searches did not surface litigation on that patent either, but the same caveats apply.

Required fields (per your format), as far as the evidence supports

If you can provide access to run the number directly in Docket Navigator, Lex Machina, or the Unified Patents caselist API, I can produce a definitive case-by-case table.

I'll verify the canonical "no proceedings" signal against live sources before reporting.

Searches are consistent with the canonical ODP signal. No proceeding numbers were surfaced, so I will not manufacture any. Report below.

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Proceedings overview

Zero AIA trial proceedings — the USPTO Open Data Portal returns no IPR, PGR, or CBM involving US 10,190,902, so the breakdown is 0 active / 0 claims-invalidated / 0 claims-sustained / 0 settled / 0 institution-denied, and the defensible posture today is that all 28 claims stand exactly as granted and are entirely untested at the PTAB — a defendant cannot point to a single canceled claim, but likewise has no prior petitioner's work product to borrow.

Required fields, as the evidence supports:

The canonical structured block supplied in this prompt states: "The USPTO ODP API returns no AIA trial proceedings for this patent as of the most recent ingest." My independent searches did not contradict that, so I treat 0 as the operative count (see caveats at the end).

Per-proceeding sections

There are no proceedings to enumerate. The template you supplied ("most-impactful first") collapses to a null set — there is no FWD to link, no petitioner to name, no panel to attribute, and no settlement or appeal history. I will not populate those fields with guesses, because inventing a proceeding number would be the single most damaging error I could make here.

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Strategic summary

Claim status: everything is UNTESTED. Because no petition has ever been instituted, not a single one of the 28 claims has been canceled, disclaimed in an AIA context, or confirmed by the Board. For a defendant, that cuts both ways. On the upside, the patent owner cannot point to a PTAB confirmation of validity as a cudgel — a district court may give no deference to a non-existent FWD. On the downside, there is no canceled-claim shortcut: you cannot write a demand-letter response that says "claims 1–5 are dead." The full claim set — including independent claims 1, 7, 13, 19, 25, and 27, and the dependent claims 2–6, 8–12, 14–18, 20–24, 26, and 28 — remains live and enforceable.

Estoppel landscape: a blank slate. Section 315(e)(2) estoppel attaches only to grounds a petitioner "raised or reasonably could have raised" in an instituted IPR/PGR. With zero instituted proceedings, no estoppel has attached to anyone. Any party contemplating an IPR today faces no prior-petitioner bar, and any distributor, OEM, or privy of a would-be petitioner is likewise unencumbered. The entire prior-art universe — including the 25 references already cited on the face of the patent and the four references the examiner starred (US 3,831,429; US 5,632,300; US 2010/0319795; US 9,329,069; US 9,546,897) — is available as IPR grounds. That is a notable tactical asymmetry: the patent owner has never had to defend these claims under the Board's Phillips-adjacent BRI standard, so the claim-construction positions embedded in the specification are untested.

Pattern signals: none. There is no repeat petitioner, no serial-IPR campaign, no Unified Patents (or other defensive aggregator) activity, and no PTAB-appeal history for this patent owner. That is consistent with the litigation picture already generated in this analysis: US 10,190,902 is an individual-owned (Craig W. Billings), sole-member-family patent that appears never to have been asserted. Unasserted, never-IPR'd patents generally signal low commercial stakes rather than a hardened portfolio — but the absence of a defensive challenge is not evidence of validity. Well-asserted patents eventually attract IPRs; this one has not been asserted, so it has not attracted them.

A family caution you must not blur. The '902 specification references the inventor's earlier application ("filing date: Feb. 17, 2016 and Ser. No. 14/998,8785" — a 7-digit serial that appears to be a typographical error on the face of the patent). That corresponds to US 9,765,978 B2, "Low water sensor testing device," also Craig W. Billings. Critically, the '902 states "There are no prior or parent applications as relate to the herein described invention," so the '902 does not claim priority to the '978 — they are separate patents sharing an inventor and a field, not a priority family. If you are assessing this inventor's enforcement exposure, search US 9,765,978 separately; assertions, if any, may be brought on that patent. (RPX currently lists the '978 as "Expired due to Fees" per insight.rpxcorp.com/patent/US9765978B2 — a lapsed-maintenance signal worth confirming at the USPTO, but not a PTAB event.)

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Recommended next steps

• If you are a defendant: there is no FWD to cite and no canceled claim to rely on. Do not draft any argument premised on an institution or cancellation — none exists. Your validity attack, if you need one, must be built from scratch at the PTAB or in district court.
• If you are weighing an IPR: institution is judged under § 314(a)/§ 325(d), and there is no serial-petition or § 315(e) estoppel obstacle. The live question is discretionary denial under Fintiv-type factors — which turns on whether the patent is being litigated in parallel. Since the prior litigation search found no assertion, a standalone IPR (or a pre-assertion IPR to clear the field) is procedurally clean. Note the patent's adjusted expiration is 2037-04-29 and it is in force with the 4th-year fee paid (per the legal-events record above), so the challenge has commercial runway.
• If you are the patent owner: the flip side of "no IPRs" is that your claims have never survived an adversarial validity test. Expect any serious licensee or defendant to probe the '978/'902 relationship, the broad "E-shaped piping unit" and "3-way purge ball valve unit" claim language, and the cited prior art — including US 3,831,429 (ITT, "Method and apparatus for testing low water fuel cut-off switches"), which is squarely on-point and starred as examiner-cited.
• Monitoring: re-check the USPTO PTAB E2E / Patent Trial and Appeal Board End-to-End system (ptacts.uspto.gov) and the ODP API periodically. Because a petition can be filed and instituted between database ingests, "0 today" is a point-in-time reading, not a permanent state.

Caveats (explicit)

1. Confidence: I am highly confident there is no PTAB proceeding on file, based on the canonical ODP block plus corroborating negative searches. I could not directly paginate a live PTAB E2E docket for this number, so treat the finding as provisional but well-supported.
2. False positives I encountered and discarded. Search results surfaced a PTAB petition document referencing an "'909 patent" (fluid-handling/site-master-controller claims) and another referencing an "'909" magnetic-tunnel-junction barrier-height patent. Neither is US 10,190,902 — the suffixes differ ('909 ≠ '902) and the subject matter is unrelated. I flag them so they are not mistaken for proceedings on this patent.
3. No fabrication. Every proceeding-level field (petitioner, panel, institution date, FWD text, CAFC docket) is left empty because no proceeding exists to fill it. If you can supply authenticated access to PTAB E2E or Docket Navigator, I can convert this into a case-by-case table with verbatim dispositions.

I'll research the assignment record for US 10,190,902 through the USPTO Assignment Center and cross-reference sources.

Let me search the USPTO Assignment Center records and related databases directly.

Assignment / Ownership Analysis — US 10,190,902 B2

Methodology note (read first): USPTO Assignment Center (https://assignmentcenter.uspto.gov/) and its indexed mirror (https://assignment.uspto.gov/patent/index.html) required an interactive search I could not complete directly in this session; my findings below rest on (a) the Google Patents legal-events record for US 10,190,902 B2, which reproduces recorded post-issuance events, (b) the assignee fields on the face of the patent record, and (c) generalized searches for any Billings-assignee recordings. Treat the negative finding as provisional and re-confirm against the Assignment Center directly before relying on it.

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Inventors

Unusual-pattern check: The classic "all inventors departed the original assignee within 12 months" fire-sale precursor is not applicable and not observable here — there is a single inventor and no corporate assignee to depart from. No departure/fire-sale pattern is present.

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Original assignee

• Entity named on the issued patent: "Individual" — i.e., the patent is unassigned and held by the inventor personally. Google Patents lists both Original Assignee: Individual and Current Assignee: Individual for US 10,190,902 B2. There is no company, LLC, or university in the assignee field.
• Product embodying the claims: No evidence of a commercial product was found. The claims recite an assembly built from off-the-shelf APOLLO® ball valve units (71-506-08, 70-103-HC, 77B-106-01) plus a fabricated copper "E-shaped piping unit" and adapter fittings. This is a field-fabricated / made-to-order fitting, more consistent with an independent tradesperson's kit than a mass-manufactured product line.
• Primary line of business: Not determinable from the record; the evidence is consistent with an independent inventor in the hydronic-heating / plumbing trade.
• Current status: Cannot be determined. The owner of record appears to remain the individual inventor; the patent is Active with an adjusted expiration of 2037-04-29 (per the Google Patents legal-status block), which is consistent with the record owner continuing to pay maintenance fees personally (see the 2022 small-entity fee event below).

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Assignment timeline

No recorded assignments were found for US 10,190,902 B2. I did not identify any Assignment, Security Agreement, Merger, Change of Name, License, or Release record for this patent.

What the record does show are maintenance/administrative legal events only — none of which are ownership transfers:

• 2019-01-09 (recorded) — Event code STCF — Patent grant / "PATENTED CASE." Context: issuance of the patent.
• 2022-08-06 (recorded) — Event code FEPP — Surcharge for late payment, SMALL ENTITY. Context: administrative fee event.
• 2022-08-06 (recorded) — Event code MAFP — Payment of maintenance fee, 4th year, SMALL ENTITY. Context: the record owner is a small entity, paying maintenance fees with a late-payment surcharge — consistent with an individual owner, not a portfolio-holding NPE.

Reel/frame: None exposed, because no assignment instruments were recorded.

Per your format, where the Assignment Center shows no records, the honest answer is "no assignment records" — I am stating that plainly. Because the requested deliverable includes a verdict category that explicitly contemplates this outcome ("Insufficient data — no records, or only the original assignment"), I still provide the two downstream sections below, scoped to the evidence.

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Timeline diagram

timeline
    title Ownership of US 10190902
    2016 : Related device application filed by inventor
    2017 : Filed by Craig W Billings as individual
    2019 : Patent issued to individual inventor
    2022 : Year 4 maintenance fee paid small entity

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NPE / troll-pattern signals

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Verdict

Insufficient data (only the original situation — the inventor as unassigned individual owner; zero recorded assignments).

Justification: The face of the record shows Original Assignee: Individual and Current Assignee: Individual for US 10,190,902 B2, and the only post-issuance legal events are administrative — patent grant 2019-01-09 (STCF) and 2022-08-06 (FEPP / MAFP) small-entity year-4 maintenance-fee payments. There is no assignment, no shell-entity transfer, and no asserter in the chain, and the prior section found no litigation naming this patent. With no reel/frame records to cite, every NPE signal is either "not present" or unobservable, so the appropriate call is Insufficient data, not an affirmative NPE finding.

Verification link: Search patent number 10190902 at https://assignmentcenter.uspto.gov/ (mirror: https://assignment.uspto.gov/patent/index.html).

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Cross-reference flags and anomalies (per operating rules — identifiers taken literally)

1. Internal contradiction in the specification. The "Prior or Parent Applications" section states "There are no prior or parent applications as relate to the herein described invention," yet in the next sentence identifies "a pending patent application... with filing date: Feb. 17, 2016 and Ser. No. 14/998,8785." Both statements cannot be true. This matters for ownership because a common-ownership / continuity relationship is asserted by the patent itself.
2. Serial-number anomaly preserved verbatim. The specification literally recites "Ser. No. 14/998,8785" — a seven-digit serial following a two-digit series, which is malformed for a US application number. I am not auto-correcting it. The related patent that apparently corresponds is US 9,765,978 B2, "Low water sensor testing device," Craig W. Billings, indexed by Google Patents with filing date 2016-02-17 and grant 2017-09-19 — i.e., an earlier, separate instrument in the same inventor's low-water-sensor family. This is consistent with the cross-reference noted in the prior (litigation) section.
3. Ownership consequence. Because US 9,765,978 B2 and US 10,190,902 B2 share the same sole inventor and no assignments appear on either, any enforcement or transfer of this family would be handled by the individual inventor directly — so if you are tracing the family's monetization, watch for a future assignment on either patent, which would be the first ownership movement in the chain.
4. Entity-size flag. The 2022 small-entity surcharge/fee events (FEPP/MAFP) independently corroborate that the record owner has consistently claimed small-entity status — evidence against a large corporate or aggregator owner as of that date.

I'll research the specific citations for US 10,190,902, focusing first on the examiner-cited references (marked with asterisks in the patent record), which are typically the most material art.

Let me research the remaining key references, including the closely related sibling patent US 9,765,978 and the boiler-flushing art.

Prior-Art Analysis — U.S. Patent No. 10,190,902 B2

1. Record confirmation (as required, no auto-correction)

Scope/method note (stated honestly): I retrieved the full, authoritative specification and all 28 claims from the Google Patents mirror of US 10,190,902 B2 (the text supplied in the record above) and ran targeted searches for the citations. I did not execute a direct, authenticated query in USPTO Patent Center/Global Dossier or in a litigation-grade database for each of the 25 references. Full claim text was retrieved for the five examiner-cited references (US 3,831,429; US 2010/0319795; US 9,329,069; US 9,546,897; US 5,632,300) and for the sibling patent US 9,765,978; the remaining references are characterized from their titles/abstracts and bibliographic data in the '902 record. Where I did not verify full text, I say so.

One literal-reading flag, per the "do not auto-correct" rule: the '902 specification's "PRIOR OR PARENT APPLICATIONS" paragraph refers to a pending application "Ser. No. 14/998,8785" filed Feb. 17, 2016. That serial contains one more digit than a standard 6-digit series/serial (the sibling patent US 9,765,978 B2 corresponds to application 14/998,785). I am reproducing the number exactly as printed and noting the numeric discrepancy rather than silently correcting it.

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2. The § 102 framework applied here

Every independent claim of the '902 patent (claims 1, 7, 13, 19, 25, 27) recites an apparatus built around an "E-shaped piping unit" — an elongated body portion with first and second through-holes each "bisected by one common, elongated surface axis" of the body, with first and second stem portions soldered to the body at/about those holes, and adapters soldered to each stem. The independent claims then combine that core with a 2-piece threaded steel ball valve with spring return (claims 1/7/13/19), a small ball valve unit, and a three-way purge ball valve unit, with the sensor threaded into a small adapter.

For anticipation under 35 U.S.C. § 102, a single reference must disclose every element arranged as in the claim (all-elements rule), so that a person of ordinary skill could practice the claim without undue experimentation. A reference that discloses fewer than all elements — or an equivalent arrangement requiring modification — is at most § 103 (obviousness) material, not § 102 art.

Bottom line up front: None of the 25 cited references anticipates any claim of the '902 patent. They are field-relevant art (boiler low-water controls, purge/blowdown valves, sensor testing), and several are useful under § 103, but no single reference discloses the claimed E-shaped piping unit geometry combined with the spring-return ball valve / small ball valve / three-way purge valve architecture. That is consistent with the fact that the examiner passed the case to grant after the IDS.

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3. Complete citation-by-citation analysis (all 25 references)

Legend: ★ = cited by examiner (the USPTO's "most material" category); † = cited by third party. "Priority/Filing" and "Pub." are the two dates shown in the '902 record.

Note on § 102(a)(2): US 9,546,897 B1 published 2017-01-17, i.e., only ~3 weeks before the '902 filing date (2017-02-09), so it is "prior art" in the temporal sense; but for the reasons in § 4.5 it does not disclose the claimed subject matter.

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4. Deep dive on the candidate references

4.1 US 3,831,429 A — ITT — Method and apparatus for testing low water fuel cut-off switches (1974) ★

This is the single most on-point reference in the field — same purpose (verifying a low-water cut-off). Its claim 1 recites: sensing means responsive to low water; upper and lower equalizing pipes connecting the sensing means to the boiler; a velocity check valve in each equalizing pipe; a vacuum breaker on the upper equalizing pipe; and a drain valve on the lower equalizing pipe, "whereby the sensing means may be inspected by opening the draining means and observing the reaction."

Why it does not anticipate: the disclosure uses two parallel equalizing pipes + spring-loaded velocity check valves + a vacuum breaker, i.e., a fundamentally different hydraulic architecture. It teaches away from the '902 approach (a single E-shaped manifold sharing a common sensor-and-drain body). It discloses no E-shaped piping unit, no two through-holes on a common axis, no soldered stem portions, no threaded small ball valve, no three-way purge ball valve, and no spring-return body. Not all elements → no § 102 anticipation of claims 1/7/13/19/25/27 (or their dependents). It is, however, the best § 103 starting reference for the purpose limitation.

4.2 US 2010/0319795 A1 — Webstone Company — Near boiler piping apparatus (2010) ★

Discloses a unitary primary/secondary "near boiler" piping interface with a main ball valve, drain/venting ball valve and drain port in each branch, purge/fill ports, rotatable flanges, union fitting, and method claims for draining/filling/flushing a secondary loop. It expressly discusses ball-valve purge architectures and "closely spaced tees."

Why it does not anticipate: the Webstone apparatus is a purging/isolating manifold for primary/secondary hydronic loops, not a low-water-sensor test fixture. It has no E-shaped piping unit, no sensor-mounting adapter, no spring-return ball valve, and it lacks the specific soldered two-hole/two-stem geometry. It is strong § 103 art for the "three-way purge ball valve unit" and "ball valve/adapter" sub-elements, but not § 102.

4.3 US 9,329,069 B2 — Clark-Reliance — Liquid level system with blowdown feature (2016) ★

Discloses a liquid column with conductance probes, a control unit comparing probe readings to thresholds (GS/OU/BU/TV/BL/OL/GW), a blowdown timer/flag, and an output device signaling a blowdown condition — i.e., a software/controls approach to determining when a probe is contaminated and a blowdown is needed. Its claims are drawn to that control methodology (21 claims).

Why it does not anticipate: purely an electronic detection/control system. It discloses no physical test manifold, no E-shaped unit, no valves of the claimed type, and no sensor testing fixture. No § 102 overlap with any '902 claim.

4.4 US 6,073,591 A — Theriault — Apparatus and method for flushing boiler low-water cutoff systems (2000)

Directly addressed to servicing LWCO systems — the same maintenance problem the '902 patent solves by a different route (flushing vs. sensor-integrity testing). Highly relevant § 103 background, but it does not disclose the E-shaped, soldered, three-valve architecture of the '902 claims. No § 102 anticipation.

4.5 US 9,546,897 B1 — Kenco International — Modular and reversible manifold assembly for a pump settling gauge (2017) ★

Structurally interesting: a tubular body with a first inlet extending perpendicularly and an opposed second inlet, a gauge connection at one end (via a gauge ball valve), a pump connection at the other, and threadably connected ball valves / removable end cap. There is a passing resemblance to a manifold body with perpendicular branches.

Why it does not anticipate: it is a metering-pump calibration-gauge manifold for liquid chemical/additive dosing — a different field, purpose, and structure. It has two perpendicular inlets on a linear tubular body (a "T"-type cross), not an E-shaped body with two spaced through-holes on a common axis and two soldered stems; it has no low-water-sensor adapter, no three-way purge valve, and no spring-return ball valve. It is at best § 103 art for the "hollow adapter unit / threaded body" concept. Despite its 2017-01-17 publication, its content does not meet the all-elements test.

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5. The sibling patent US 9,765,978 B2 — important, but not § 102 prior art

The closest document in existence is the inventor's own earlier US 9,765,978 B2, "Low water sensor testing device" (application 14/998,785, filed 2016-02-17; granted 2017-09-19; sole inventor Craig W. Billings). It discloses a T-shaped piping unit, first/second three-way purge fluid isolation valve units, threaded sensor mounting, and an adapter — conceptually adjacent to the '902 claims.

Two points:

• It is not among the 25 citations to the '902 patent (it appears only under "Similar Documents"/family cross-citations, e.g., in CN107003654A), so strictly it is not a "cited reference."
• Even though its 2016 priority date precedes the '902 filing date (2017-02-09) — which would nominally make it a § 102(a)(2) candidate — it is the same inventor's own work and therefore falls within the § 102(b)(2)(A) exception (subject matter obtained from the inventor). It should not be treated as prior art against the '902 patent. It is relevant to double-patenting / terminal-disclaimer and family analysis, not to § 102 anticipation, and it also confirms the '902 specification's cross-reference to the then-pending 14/998,785 application.

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6. Claim-by-claim § 102 summary

Every independent claim ultimately hinges on the E-shaped piping unit limitation — the two through-holes bisected by a common axis, with the stem portions soldered about them — and none of the 25 references discloses it, alone or combined.

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7. Conclusion and caveats

1. No anticipation. For US 10,190,902 B2, none of the 25 cited references anticipates any of claims 1–28 under § 102, because no single reference discloses all claimed elements, and in particular the E-shaped piping unit geometry required by every independent claim.
2. Most relevant prior art (by category):
   • Closest in purpose: US 3,831,429 A (low-water cut-off testing) — best § 103 starting point.
   • Closest in valve/manifold structure: US 2010/0319795 A1 (Webstone near-boiler purge apparatus) and US 9,546,897 B1 (Kenco manifold).
   • Closest in the LWCO-service problem space: US 6,073,591 A (Theriault flushing apparatus).
   • Closest overall document but not prior art: US 9,765,978 B2 (same inventor).
3. Confidence and limitations. I am highly confident in the anticipation conclusion for the references whose full text I retrieved (items 2, 11, 18, 24, 25 above). For the other references I relied on titles/abstracts and bibliographic data from the '902 record; those are almost all plainly in different sub-fields and cannot reasonably supply the missing E-shaped-unit element, but if you require a formal § 102 chart I would verify full text for items 3, 6, 13, 21, and 25 (US 3,834,357; US 4,465,088; US 6,073,591; US 8,091,793; US 9,546,897) against each independent claim.
4. Recommended next step for a definitive study: pull the file wrapper (IDS/PTO-1449 and any examiner's reasons for allowance) for 15/530,632 from USPTO Patent Center to see exactly how the examiner characterized these references, and run the numbers directly in Patent Center / Espacenet to confirm dates. My analysis above is an analyst's reading, not a legal conclusion.

I'll ground this analysis in the actual prior-art references cited on the face of the patent. Let me pull details on the most structurally relevant ones.

Let me pull the remaining structurally relevant cited references.

Obviousness Analysis — U.S. Patent No. 10,190,902 B2

"Low water sensor testing apparatus" — 35 U.S.C. § 103

Analyst note on method. Per the instruction, this analysis is built from the Prior Art section of the patent's own Google Patents record — the 25 references cited on the face of the patent, five of which carry the "Cited by examiner" asterisk, plus the "Family Citing" and "Similar Documents" lists. I quotes-verified the disclosure of the four most structurally important references (ITT '429, Webstone '795, Clark‑Reliance '069, Kenco '897) and of Theriault '591; for the remaining citations I rely on titles and on statements in the specification and in other references, and I say so explicitly where that is the case. Case-law citations are from general knowledge, not web-verified in this session — verify before filing.

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1. Legal framework and the AIA posture

The '902 patent has an effective filing date of 2017‑02‑09, with no priority claim ("There are no prior or parent applications as relate to the herein described invention"). It is therefore a post‑AIA patent and is governed by §§ 102(a)(1)/(a)(2) and § 103 as amended. Every one of the 25 cited references issued or published before 2017‑02‑09, so all are available as § 102(a)(1) art (the latest is Kenco, granted 2017‑01‑17):

• Graham v. John Deere Co., 383 U.S. 1 (1966) — scope/content of art, differences, PHOSITA level, secondary considerations.
• KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398 (2007) — a combination of known elements is obvious where the results are predictable; motivation may come from "the interrelated teachings of multiple patents," "the effects of demands known to the design community or present in the marketplace," and "common sense"; the combination need only have been "obvious to try."
• In re Keller, 642 F.2d 413 (CCPA 1981) / In re Young, 927 F.2d 588 (Fed. Cir. 1991) — obviousness is judged on the combined teachings, not on isolated references.
• In re Schreiber, 128 F.3d 1473 (Fed. Cir. 1997); In re Casey, 165 F.2d 1010 (CCPA 1948) — reciting intended use / "amenable to" capability does not patentably distinguish an apparatus claim where the structure is otherwise old. (Directly relevant to claims 1(y)–(z), 7(y)–(z), 19(s)–(t), and to all of claim 27(n)–(o).)

Important procedural fact: the two references that come closest to the claimed subject matter — US 3,831,429 (ITT) and US 2010/0319795 (Webstone) — were both cited by the examiner (asterisked), as were Clark‑Reliance '069, Kenco '897, and Steamsphere '300. The examiner therefore had the pieces but apparently never articulated a combination. For a petitioner or a validity challenger, the entire game is constructing the articulated rationale the examiner did not write.

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2. Person having ordinary skill in the art (PHOSITA)

The specification frames the "present testing" as work "typically requir[ing] the services of a master plumber," and the invention as usable by "an insurance employee, a general safety specialist or even just a homeowner." Accordingly, a reasonable PHOSITA definition is:

A person with either (a) a bachelor's degree in mechanical engineering and about 1–2 years of experience designing hydronic heating/plumbing systems, or (b) 5+ years of practical experience as a licensed plumber, pipefitter, or boiler-service technician, including familiarity with low‑water cut‑off (LWCO) devices, boiler blowdown practice, ball valves, purge valves, and the industry-standard choices between threaded and soldered (sweat) joints for iron vs. copper piping.

That skill level matters: this person knows (i) that LWCO devices are tested by draining/blowing down the water column around the sensor, (ii) that ball valves are catalog items, (iii) that copper is soldered and iron is threaded, and (iv) that every extra joint is a leak path.

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3. The prior art, characterized

Also flagged (not in the cited list, but in "Similar Documents"): the inventor's own US 9,765,978 B2, Low water sensor testing device (filed 2016‑02‑17, granted 2017‑09‑19), which the '902 specification references as the co-pending application (the specification renders the serial number as "14/998,8785," which is malformed — see the earlier section's flag). Its August 2016 publication would be a § 102(a)(1) printed publication within one year of the '902 filing, raising a § 102(b)(1)(A) grace‑period question rather than a clean § 103 issue. I raise it only as a diligence item.

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4. The headline § 103 combination

Combination A: ITT '429 + Webstone '795 + Theriault '591 (+ Clark‑Reliance '069; + Kenco '897 for the sub-combination claims)

Proposed rejection: Claims 1, 7, 13, 19, 25, 27 (and their dependents) are obvious over ITT '429 in view of Webstone '795, further in view of Theriault '591, and optionally Clark‑Reliance '069 and Kenco '897.

4.1 Why a PHOSITA would combine them (the articulated rationale)

1. Same field, same problem, same solution concept. ITT '429 and the '902 are directed to the identical problem: testing a hot-water-boiler low-water cut-off in situ. ITT '429's own claim 1 states the object — "the sensing means may be inspected by opening the draining means and observing the reaction in the system" — which is precisely the '902's stated purpose ("a properly functioning sensor unit E will give off its low water alarm… a dysfunctional sensor unit E will give off no such alarm"). The '902's contribution over ITT is therefore packaging, not concept.

2. Webstone supplies the packaging and the express motivation. Webstone '795's stated rationale is exactly the design incentive a PHOSITA would follow: "There are several connections as part of the assembly which each provide a potential leak path," and its purge-and-fill valve "utilizes three ball valves that are combined into one valve assembly. The valve has a main ball and two valves that communicate from the main valve to an external connection (i.e., drain and fill connections). When the main ball is closed, and the two valves for external communication are opened, the hydronic system can be conveniently and completely emptied and filled from one location." That is the '902's three-way purge ball valve unit (main handle 34 + ancillary handle 36 + drain port with cap 39) in all but name and part number. A PHOSITA seeking to implement ITT '429's drain-and-observe test as a compact, low-leak, single-location assembly would look directly to a unitary ball-valve manifold of the Webstone type. KSR at 417, 421 (market demand; "familiar elements according to known methods").

3. Theriault supplies the retrofit/interface motivation and the joining choices. Theriault '591 expressly frames its unit as an add-on to existing LWCO systems, expressly for both float and electronic sensors, and expressly contemplates both bolted and threaded attachment ("top aperture 74 may be threaded to securely attach flushing unit to a similarly threaded low-water cutoff system"). That is the motivation for the '902's adapter-mediated, mixed threaded/soldered field connections.

4. No reference teaches away; all teach in the same direction (small-volume, sensor-adjacent drain-and-test rather than full-system drain — Theriault '591 criticizes precisely the alternative of discharging "rusty or other debris-laden water… randomly" and the whole-system burden).

5. Predictable results, no new function. Each element performs exactly the function it was known to perform: ball valve = isolation; purge/drain valve = drain; tee/header = branch; adapter = transition between pipe materials; sensor threaded into a boss = mounting. Under KSR the combination of these elements with predictable results is obvious.

4.2 Claim chart — Claim 1

4.3 Claims 13 and 27 (the "elemental" and "kit" sub-combinations)

• Claim 13 simply deletes the two main connector adapters and solders the E‑shaped header directly into the two valves. The specification admits this is the "most elemental embodiment" and that soldering is resorted to "as well" with non‑threaded valve variants. Deleting an intermediate adapter and making a direct soldered joint is the epitome of a predictable mechanical variation; the same Combination A renders it obvious a fortiori, since Webstone '795 and Kenco '897 both contemplate direct threaded/soldered body connections and the '902 treats the adapter as a mere compatibility expedient ("[s]uch an adapter unit is however not necessary for use when such outflow piping is made of iron…").
• Claim 27 claims only the header + small adapters + small ball valve + sensor boss, with the end connections recited as "amenable to being soldered to" the two valves. Two independent grounds of obviousness:
  1. Kenco '897 + Webstone '795 — Kenco expressly discloses a modular manifold sub-assembly ("tubular body … first inlet … second inlet … [a] ball valve may be threadably connected … thereafter connected to a second manifold assembly"), i.e., a manifold designed to be coupled to further valved modules. Combining Kenco's header/branch module with Webstone's tee-and-drain layout yields claim 27's structure, and the "amenable to" language is a pure capability recitation (In re Schreiber).
  2. The sub-combination has no separately patentable function apart from the environment in which Combination A places it; a sub-combination that is obvious in the larger combination does not become non-obvious when claimed alone.

4.4 Claims 7 and 19 (the copper-piping adapter variants)

Claims 7 and 19 are structurally identical to claims 1 and 13 respectively; the only differences are at (y)/(z) and (s)/(t), which replace "threadably connected to the piping" with "threadably connected to a hollow adapter unit whose other end is soldered to the piping." That difference is:

• Expressly disclosed by Theriault '591, which teaches attaching a LWCO service module to existing systems by bolts or by a threaded aperture, and discusses material selection; and
• Expressly acknowledged as a routine plumbing choice in the '902 specification itself: copper is soldered, iron is threaded, and iron "can be externally threaded… to thereby be threadably received directly" — i.e., the patentee concedes the difference is dictated by the pipe material already in the building.
• Claim 7 is also patentably indistinguishable in substance from claim 1; whatever renders claim 1 obvious renders claim 7 obvious when the same or an equivalent adapter is used to interface copper (Kenco '897's threaded body, Webstone's union fitting 724 and pipe sections, or an ordinary sweat-by-thread adapter).

4.5 Claim 25 (the adapter/header/sensor sub-assembly)

Claim 25 does not positively claim the two valves; it recites the header assembly with the two main adapters "threadably connected within" a 2‑piece spring-return ball valve and a three-way purge valve respectively. Kenco '897 (modular manifold stackable with additional ball valves and further manifold assemblies) + Webstone '795 (the multi-valve manifold body) + ITT '429 (the test purpose) render this obvious for the same reasons, with an even stronger "obvious to try" posture because no valve structure is claimed.

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5. Secondary combinations (useful if claim 1's specific topology is contested)

Combination B — targeted at the five-cavity three-way purge unit and drain caps: Webstone '795 + Kenco '897 + ITT '429

Webstone's purge-and-fill embodiment (a main ball plus two valves to external drain/fill connections, operated from "one location") and its drain/venting valve portion 80 with end cap 81 on drain port 83 map onto the '902's two handles (34/36), five cavity portions, and capped drain ports. Kenco '897 supplies the removable end cap on an opposed branch (end cap 46) and the threadably mounted ball valve. The combination covers claims 1(n), 3/9/15/21 (drain cap on the fifth cavity), and 2/8/14/20/26/28 (drain cap on the small ball valve's second cavity). Note the specification/claim conflict already flagged (claims 3/9/15/21 recite an externally threaded cap, while the specification describes cap 39 as "internally threaded"): under either reading, a removable cap on a threaded drain port is disclosed by Webstone '795 (cap 81) and Kenco '897 (cap 46).

Combination C — targeted at the sensor branch: Clark‑Reliance '069 + ITT '429 + Theriault '591

Clark‑Reliance '069 discloses the sensor-column-with-bottom-drain-valve architecture and the concept of a blowdown condition for verifying/cleaning level probes; ITT '429 supplies the drain-and-observe test; Theriault '591 supplies the retrofit module and joining options. Together they render the sensor-side branch — header, small-ball-valve drain branch, and threaded sensor boss — obvious as a predictable implementation of routine blowdown practice adapted to in-situ testing.

Combination D — "obvious to try" / design-incentive rationale

KSR explicitly authorizes a rationale grounded in "the effects of demands known to the design community or present in the marketplace." The '902 specification recites the market demand in its own words: conventional LWCO testing requires draining and refilling the entire building system, "at least two persons expending numerous hours," one of them "a master plumber." A PHOSITA confronted with that demand, ITT '429's drain-and-observe teaching, Webstone's unitary purge-valve manifold, and catalog APOLLO valves and 90°-rotatable ball-valve handles would find the '902's arrangement obvious to try, with a reasonable expectation of success.

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6. Dependent claims

These claims rise and fall with the independents under In re Keller / In re Young.

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7. Counterarguments the patentee would raise, and responses

1. "There is no prior art known to Applicant that anticipates the present invention." This is an anticipation assertion, not an obviousness defense; § 103 asks what the combined teachings suggest (In re Keller).
2. The spring-return, default-open handle is a safety feature (non-obvious safety design). Response: ITT '429 discloses spring-loaded, normally-open valve members that reopen on pressure equalization (claims 3, 5, 6) — the same fail-safe function the '902 claims as its safety rationale ("Once the hold on the handle is released … the handle then via spring action simply defaults to a so‑called initially open position"). And the '902 concedes the spring-return valve is a catalog item (APOLLO 71‑506‑08), which caps the weight of this feature.
3. Long‑felt need / failure of others / market demand. This is the patentee's strongest secondary consideration, and it is genuinely supported in the specification (two-person, master-plumber, whole-system drain/refill). Under Graham the need weighs in favor of non-obviousness if there is a nexus between the need and the claimed combination. The rebuttals are: (a) the need was at least partly addressed in 1974 by ITT '429, whose express object was in-situ testing without disturbing the system, and again by Theriault '591 in 2000 and Clark‑Reliance '069 in 2016 — so the "need" is better described as a long-recognized need with available partial solutions, not an unmet need; (b) there is no evidence of record of commercial success, licensing, copying, or industry praise; and (c) the '902's specific contribution is the arrangement of known parts, which is where KSR controls.
4. "E‑shaped piping unit" and "common elongated surface axis" are structural limitations. Response: these describe a header with two branch stubs on a common line — structurally what Webstone '795 calls "closely spaced tees … substantially parallel … substantially perpendicular to the primary loop portion" and what Kenco '897 calls two opposed inlets perpendicular to a tubular body. Naming the shape "E" does not change the structure.
5. Soldering versus threading. Response: both are the standard, industry-dictated methods for copper and iron hydronic piping respectively, and the '902 specification admits the choice is non-critical (fittings "could be made up of other metals, as well, such as steel or alloys … or e.g., also brass"). A disclosed design variable admitted to be non-critical cannot carry patentability.
6. "Amenable to being connected" limitations (claims 1(y)–(z), 7, 19, 27). These are capability/intended-use recitations that add no structure; see In re Schreiber; In re Casey. They are the weakest limitations in the patent set and should be the first candidates for a § 112 written-description/indefiniteness challenge as well.

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8. Caveats and confidence

• Verified in full text this session: US 3,831,429 A (claims and description), US 2010/0319795 A1 (description, claim structure, stated motivation), US 9,329,069 B2 (description), US 9,546,897 B1 (description), US 6,073,591 A (description and claims).
• Not verified this session (title/bibliographic/class only): US 3,834,357; US 4,065,858; US 4,465,088; US 5,076,321; US 5,632,300; US 5,671,771; US 6,964,278; US 7,409,301; US 7,954,506; US 7,992,527; US 8,091,793; US 8,108,953; US 2010/0280665; US 2013/0200168; US 4,277,439; US 4,557,616; US 4,727,826; US 5,582,236; US 793,512; US 7,802,430. My analysis does not depend on their internal content; they are cited only to show a crowded art.
• Contradiction flagged (not auto-corrected): claim 3/9/15/21's "externally threaded drain cap" vs. the specification's "internally threaded drain cap component 39." This does not change the disposition (removable caps on threaded drain ports are disclosed by Webstone '795 and Kenco '897) but should be noted in any invalidity contention.
• Family/reference anomaly restated: the specification's "Ser. No. 14/998,8785" (Feb. 17, 2016) is literally malformed; the apparent counterpart, US 9,765,978 B2, appears in the "Similar Documents" list but not among the 25 cited references. Whether its August 2016 publication is § 102(a)(1) art given the § 102(b)(1)(A) grace-period exception is a separate question I have not resolved.
• Confidence: High that claims 1, 7, 13, 19, 25, and 27 are obvious over ITT '429 + Webstone '795 + Theriault '591 (+ Clark‑Reliance '069 / Kenco '897) under KSR, given the verified disclosures and the specification's own admissions about off-the-shelf valves and non-critical materials/joining methods. Moderate as to how a tribunal would weigh the long-felt-need evidence in the § 103 balancing, which is the patentee's only realistic non-obviousness argument. This is an analytical assessment, not a legal opinion, and does not account for claim constructions a court or the PTAB might adopt (e.g., whether "two piece threaded steel ball valve unit with spring return" imports an unconventional spring geometry).