US 11181432

I'll search for the specific patent number and any related litigation/docket activity.

Let me check for any litigation or CAFC docket activity and verify the bibliographic data.

Search results note

I searched for the literal string 11181432 in patent and litigation contexts. Important caveat up front: my searches returned no USPTO litigation record and no CAFC 2026 docket entry for US Patent 11,181,432. The number "11181432" does appear in other contexts, but these are unrelated and I am not conflating them:

• EP 11181432.3 — a European application number (Oki Data Corporation, "Driving device and image forming apparatus," published as EP 2431815 A2/A3). Different numbering system, different subject matter.
• Random "11181432" hits in Texas county payroll ledgers — not patent records.

No PTAB/Court of Appeals for the Federal Circuit document mentioning this patent appeared in the searches. I cannot affirmatively confirm the absence of litigation; I can only report that no such record surfaced. The bibliographic data below is drawn from the authoritative full text you supplied (Google Patents), cross-checked against Espacenet.

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US 11,181,432 B2 — Bibliographic summary

Family / counterparts: WO 2018/028931 A1 (ceased); EP 3 497 420 A1 (withdrawn); CN 109791085 A (reported active/pending); DE 10 2016 114 846 A1 (withdrawn). Related earlier family: DE 10 2013 110 059 A1 / US 9,683,876 B2, which is cited in the specification as the baseline blockage-detection technique.

Abstract (as issued): A method for diagnosing a differential pressure line of a differential pressure measurement arrangement includes capturing a first set number of differential pressure values representing a difference between a first media pressure and a second media pressure within a process, and checking whether the differential pressure measurement arrangement and/or the process are in a state that allows a diagnosis of the differential pressure line. Where it is determined that they are not in such a state, the differential pressure values are captured anew such that the previously captured values are deleted or overwritten. Otherwise, a diagnostic function to determine whether a differential pressure line is blocked is carried out.

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Plain-language overview of the independent claims

Claim 1 — the apparatus. A differential-pressure measurement setup with the usual hardware: a differential-pressure transducer that produces a differential-pressure value from two media pressures; a high-side pressure line into one inlet; a low-side pressure line into the other inlet. On top of that hardware, a diagnostics unit is programmed to do the following:

1. Take a batch of differential-pressure readings.
2. Decide whether the arrangement and/or the process is in a condition that permits a meaningful blockage diagnosis.
3. If not suitable: throw that batch away (delete or overwrite it), take a fresh batch, and re-test — looping until conditions are suitable.
4. If suitable: run the blockage-diagnosis function on the retained batch.

The claim then closes the loop with a definitional limitation: the "diagnosis-enabling" state is defined as the arrangement being in a stable state, and stability is defined as the captured values falling within a first range at a predefined frequency.

Claim 4 — the method. The same a)–d) logic expressed as method steps for diagnosing a differential-pressure line of such an arrangement: capture a first set of differential-pressure values; determine whether the arrangement/process permits a diagnosis; if not, capture a new set and delete/overwrite the first set, and repeat the determination; if yes, use the retained set to perform a diagnostic function for blockage. Claim 4 carries the same closing limitation as claim 1 — the enabling state is defined as the arrangement being in a stable state, where stability means the captured values are within a first range at a predefined frequency.

Key dependent-claim context (for completeness):

• Claims 2–3 (apparatus) and 10–15 (method) add the second gate: checking whether the process has undergone a significant change, defined as the average of a further set of values falling outside a defined second range; the second range is operator-set or defaults to a triple standard deviation (±3σ) about a mean.
• Claims 5–9 situate the "first range" — it includes a standard deviation of an earlier-captured second set of values taken while the process was known stable (e.g., at initial commissioning).

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Summary of what I could and could not verify

• Verified (high confidence): All bibliographic fields, abstract, claim text, family members, and legal-status events above come from the authoritative full text of US 11,181,432 and are corroborated by Espacenet's bibliographic record (inventors Yang/Jehle/Parrotto; applicant Endress+Hauser SE+Co. KG; application US201716323967; priority DE201610114846).
• Not verified / no record found: Any CAFC 2026 docket activity, district-court case, ITC action, or PTAB proceeding involving US 11,181,432. My searches did not surface one. I state this as "no record found," not as a positive finding that none exists — confirming litigation status reliably requires querying docket-specific databases (PACER, CourtListener/RECAP) directly, which these searches did not reach. The PTAB and PTAB-committee materials that appeared in results concern unrelated patents (e.g., IPR2025-01451, IPR2026-00058, PGR2026-00001) and should not be attributed to this patent.
• Note on the "expired" status: Google Patents shows a maintenance-fee lapse effective 2025-11-23 with an adjusted expiration of 2038-07-05. Since today's date in the query is April 26, 2026, this lapse predates the current date; treat it as the listed status, not as a legal conclusion.

I'll search for litigation involving US patent 11181432 across patent litigation resources.

Let me search additional litigation-specific sources to be thorough.

Let me check a couple more litigation-specific databases to confirm.

Findings: Litigation involving US Patent No. 11,181,432

No litigation is known involving US Patent No. 11,181,432.

I searched patent-litigation-oriented resources (including Google Patents' litigation/legal-events data for the patent, the Unified Patents litigation portal, and general CAFC/PACER-style sources), and I found no district court case, no PTAB proceeding (IPR/PGR/CBM), and no CAFC appeal in which US 11,181,432 has been asserted, challenged, or otherwise at issue.

What I did find (and why it is NOT this patent)

To avoid any confusion, I want to be explicit about the near-miss hits that appeared for the string "11181432," none of which relate to US Patent No. 11,181,432:

I excluded the '814 patent litigation (VirtaMove) because it is a different patent number even though the digits "814" overlap.

Patent status and context (from the authoritative record)

• Patent: US 11,181,432 B2 — "Differential pressure measurement arrangement and method for identifying blocked differential pressure lines"
• Assignee: Endress+Hauser SE+Co. KG
• Inventors: Long Yang, Max Jehle, Davide Parrotto
• Appl. No.: 16/323,967; filed 2017-07-14; granted 2021-11-23
• Priority: DE 10 2016 114 846.6 (2016-08-10); PCT/EP2017/067824
• Status: Per the record, Expired – Fee Related / Lapsed for failure to pay maintenance fees, with an effective lapse date of 2025-11-23 (maintenance-fee lapse events dated 2025-12-29 and 2026-01-20).
• Family: Also published as DE 10 2016 114 846 A1, WO 2018/028931 A1, EP 3497420 A1, CN 109791085 A, US 2019/0242773 A1.

The listed "Cited by / Similar documents" (e.g., US 9,203,932; US 9,683,876; US 10,006,790) are prior-art/related references, not litigation.

Caveats

• I could not access paywalled litigation databases (e.g., Docket Navigator, Lex Machina) directly, and the free "litigation" tab on Google Patents and Unified Patents' case list returned nothing for this patent number. My conclusion rests on those public sources.
• Given the patent lapsed in late 2025, it is unlikely (though not impossible) that any newly filed suit would exist; but if you need a definitive negative, a PACER/lex Machina-confirmed search keyed to the exact 8-digit number 11,181,432 would be the confirming step.
• Per the operating rule, I am interpreting the identifier literally as US 11,181,432 and not substituting any similar number.

Bottom line: No litigation — district court, PTAB, or appellate — is known for US Patent No. 11,181,432.

PTAB Proceedings — US 11,181,432 B2

"Differential pressure measurement arrangement and method for identifying blocked differential pressure lines"
Patent Owner: Endress+Hauser SE+Co. KG (DE) · Priority 2016-08-10 · Filed 2017-07-14 · Granted 2021-11-23

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Proceedings overview

Total AIA trial proceedings on file: 0 (zero). The canonical USPTO Open Data Portal "PTAB proceedings on file" block returns no AIA trial proceedings for US 11,181,432 — no IPR, no PGR, no CBM — so the breakdown is 0 active / 0 claims invalidated / 0 claims sustained / 0 settled / 0 institution denials, and I found no PTAB, Board, or Federal Circuit record of any trial involving this patent in follow-up web searching (searches run 2026‑09‑29; see caveat below on a serious false-positive risk). The bottom-line defensive posture is therefore not "hardened patent" and not "claims canceled" — it is "no PTAB road map exists, and the stronger defense sits outside the PTAB entirely: the patent has lapsed for non‑payment of maintenance fees." Per the legal‑events record, the patent expired on 2025‑11‑23 (lapse posted 2025‑12‑29, "PATENT EXPIRED FOR FAILURE TO PAY MAINTENANCE FEES," entity status large entity). A defendant today should be verifying that lapse in USPTO Patent Center before spending a dollar on prior art — but should also recognize that a § 1.378 petition to revive is still theoretically available to the owner, so "no IPR on file" plus "lapsed" should be confirmed, not assumed.

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Per-proceeding detail

None to report. There are no proceeding numbers to enumerate, and I will not invent any. Specifically:

• No IPR petition was ever filed against US 11,181,432.
• The PGR window (9 months from the 2021‑11‑23 grant) closed on 2022‑08‑23 with no PGR filed. PGR is now statutorily unavailable.
• CBM review is unavailable both on the merits (this is a process‑instrumentation/measurement patent, not a "financial product or service") and because the § 18 CBM program sunset on 2020‑09‑16.
• No ex parte reexamination or reissue record surfaced either.

Important search caveat — do not confuse this patent with U.S. Patent 7,519,814

This is the single biggest trap in researching this asset. The web is saturated with PTAB filings, POPRs, and a Federal Circuit opinion-below relating to U.S. Patent No. 7,519,814 — the VirtaMove Corp. patent asserted against Google, Oracle, Amazon, Microsoft, and IBM (IPR2025‑00487, ‑00488, ‑00489, ‑00490, ‑00561, ‑00563, ‑00566, ‑00591, ‑00599, ‑00849…‑00852, plus Oracle IPR2025‑00964/‑01001/‑01002 and related '058‑patent petitions). The shorthand "'814 patent" in that VirtaMove/Google family refers to 7,519,814, not 11,181,432. A paralegal querying "'814 patent IPR" will get a mountain of hits that have nothing to do with Endress+Hauser's differential‑pressure patent. Treat every "'814" result as a false positive unless the number is spelled out as 11,181,432.

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Strategic summary

Claim status. Because no AIA trial was ever instituted, there is no IPR‑driven narrowing of this patent at all. Claims 1–3 (apparatus) and claims 4–16 (method) stand exactly as granted and as shown in the printed claim set: claim 1 recites the differential‑pressure transducer + first/second differential pressure lines + a diagnostics unit that captures a first set of pressure values, determines whether the arrangement/process is in a diagnosable state, re‑captures and deletes/overwrites the values if not, and otherwise runs the blockage diagnostic function — with the "state enabling a diagnosis" defined by the "first range at a predefined frequency" stability test. None of claims 1–16 is canceled; none is confirmed by a Board; all 16 are UNTESTED at the PTAB. The corollary is that there is also no claim construction, no Board‑tested priority analysis, and no Board‑adopted prior‑art finding you can borrow.

Estoppel landscape. There is no § 315(e)(2) estoppel against anyone — estoppel requires a petitioner and a final written decision, and there is neither. That cuts both ways: no one is estopped, and you are not bound by anyone's failed theories. Every ground is theoretically open if the patent is ever revived: § 102 and § 103 on U.S. Pat. 5,680,109 (Foxboro impulse‑line blockage detector), U.S. Pat. 6,654,697 / 6,532,392 / 6,119,047 and U.S. Pub. 2002/0029130 (Rosemount flow‑diagnostic family), DE 10 2004 058 424 A1 (ABB), DE 10 2006 004 582 A1 (Siemens), JP 2007‑292733 A (Yokogawa), U.S. Pub. 2014/0025318 A1 (Azbil), U.S. Pub. 2016/0054162 A1 (Schlumberger), and CN 101120238 A — all of which appear on the face of the patent's own citation list. Most interesting for an obviousness attack is the patent owner's own earlier work: DE 10 2013 110 059 A1 / U.S. Pat. 9,683,876 B2 (Endress+Hauser, published 2015‑03‑12), which the specification expressly names as the diagnostic function to be run in step d). A reference that the patent itself directs the reader to use is strong § 103 fodder against claims 1 and 4, which arguably add only a gating/stability pre‑check on top of it. Note also the practical bars: the § 315(b) one‑year clock runs from service of a complaint, and Fintiv/the March‑26‑2025 Interim Workload Management memo (heavy expert‑declaration reliance, parallel petitions) are live discretionary‑denial levers for a patent owner here.

Pattern signals. The picture is the opposite of a serial assertion campaign. This is a large German operating company's process‑instrumentation patent (Deltabar product line), part of a family with DE 10 2016 114 846 A1 (withdrawn), EP 3 497 420 A1 (withdrawn), WO 2018/028931 A1 (ceased), and CN 109 791 085 A (pending/active). It was never asserted in a U.S. district court action that I could locate, which is precisely why no IPR ever materialized — the absence of PTAB activity here is a commercial signal, not a defensive shield: nobody challenged it because nobody was being sued on it. There is no defensive aggregator (no Unified Patents involvement), no repeat petitioner, no PTAB appeal record, and therefore no Federal Circuit docket to report. The only post‑grant event of consequence in the file is the maintenance‑fee lapse.

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Recommended next steps

1. Confirm the lapse first. Pull the fee record and current status for US 11,181,432 in USPTO Patent Center (application 16/323,967). The legal‑events data show expiration for non‑payment of maintenance fees effective 2025‑11‑23, posted 2025‑12‑29. If that stands and no § 1.378 petition to revive has been filed, the patent is unenforceable for the unrevived period and any demand letter citing claims 1–16 should be answered on that ground alone — with the caveat that revival on a showing of unintentional delay remains possible and carries intervening‑rights consequences under 35 U.S.C. § 41(c)(2).
2. Do not build a defense around a nonexistent FWD. There is no Final Written Decision to link or quote, and I have deliberately quoted none. If opposing counsel or a demand letter references "the IPR" or "'814 IPR," assume they mean U.S. 7,519,814 (VirtaMove) and call it out.
3. If the patent is revived or reasserted, the IPR clock is your lever. Under § 315(b) you have one year from service of a complaint. Any petition should lead with the Endress+Hauser family art — U.S. Pat. 9,683,876 B2 / DE 10 2013 110 059 A1 — combined with the Rosemount flow‑diagnostic family (U.S. 6,654,697; 6,532,392; 6,119,047) for the "determine whether the arrangement/process is in a diagnosable state before diagnosing" limitation of claims 1 and 4, which is the only feature that distinguishes this patent from its own admitted prior art. Budget for a focused, non‑bloated petition and a single expert declaration to blunt the current discretionary‑denial posture.
4. Standing order of battle: (a) status/enforceability check, (b) invalidity contentions preserved under § 282 for trial, (c) IPR petition only if the patent is revived and you are served — and only inside the § 315(b) window.

Confidence note: I am confident there is no PTAB proceeding of record against US 11,181,432 as of 2026‑09‑29 based on the canonical ODP block plus searches; I cannot rule out an unindexed filing in the last few weeks, and the maintenance‑fee lapse data should be re‑verified at the source before it is relied on in a filing or a demand response.

I'll research the assignment record and check for any NPE activity before compiling the ownership analysis.

I have enough to compile the ownership analysis. One important cross-reference issue to flag up front.

Contradiction flagged: The earlier generated "summary" section states "Since today's date in the query is April 26, 2026…" The current task sets today's date as 2026-09-29. I treat the current instruction as controlling. This does not change the substantive analysis — the maintenance-fee lapse (effective 2025-11-23) predates either date — but the "as of" framing differs.

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Inventors

All three are named on the US grant, the pre-grant publication US 2019/0242773 A1, and the PCT publication WO 2018/028931 A1. Their assignor declarations were executed 2018-12-18 to 2018-12-19 and recorded 2019-02-07.

Pattern assessment — no adverse signals. The usual red flag ("all inventors departing the original assignee within 12 months of filing, preceding a fire-sale") is not present here. The gap between the 2016-08-10 priority filing and the December 2018 execution of the assignment is attributable to the PCT national-stage timing (the US application 16/323,967 is the §371 national stage of PCT/EP2017/067824), not to inventor attrition. There is no evidence of inventors leaving Endress+Hauser, and each inventor assigned to the applicant, not away from it. I found no record of any inventor subsequently forming or joining a licensing entity in connection with this patent.

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Original assignee

Endress+Hauser SE+Co. KG (Hauptstrasse 1, 79689 Maulburg, Germany) — named assignee on the issued patent and on the recorded assignment.

• Primary line of business: Industrial process automation instrumentation — flow, level, pressure, temperature, and liquid-analysis measurement (pressure/differential-pressure devices are marketed under the Deltabar brand, expressly referenced in the specification). Endress+Hauser is a large, family-owned German group with roughly three million sensors/systems shipped annually.
• Does it ship a product embodying the claims? Substantially yes. The claims recite a differential-pressure measurement arrangement (transducer + high/low pressure lines + a diagnostics unit) and a method of blockage diagnosis. Endress+Hauser's Deltabar differential-pressure transmitters are the commercial platform described in the patent's own detailed description, and the assignee holds a large branded portfolio of differential-pressure sensor and transmitter patents in the same class (G01L13/00–13/025, G01F1/34–1/363).
• Current status: Operating company, not acquired, not dissolved, not in bankruptcy. The patent's lapse (see below) reflects a routine maintenance-fee decision on one case, not corporate distress — the assignee is actively filing (its subsidiaries' IP profiles show filings through 2024).

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Assignment timeline

The USPTO record for US 11,181,432 contains exactly one recorded assignment — the standard inventor-to-corporate-assignee conveyance. There are no post-issuance assignments (no relicense, no transfer, no security interest). Full entry:

• 2018-12-18 / 2018-12-19 (executed — signing dates span two days) / recorded 2019-02-07 — Reel 048286 / Frame 0055
  • Conveyance: Assignment of assignors' interest (recorded in the USPTO assignment system as ASSIGNMENT OF ASSIGNORS INTEREST; event code AS, "Assignment")
  • Assignor: YANG, Long; JEHLE, Max; PARROTTO, Davide (individual inventors)
  • Assignee: Endress+Hauser SE+Co. KG (Germany) — entity status recorded as Large Entity / Undiscounted
  • Correspondent: Not retrievable from the sources I could reach. The Google Patents legal-events record for reel 048286/0055 lists the reel/frame, the assignors, the signing dates, and the recording date but does not expose the correspondent attorney/firm. The Assignor name string and the assignment text ("ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:YANG, LONG;JEHLE, MAX;PARROTTO, DAVIDE;SIGNING DATES FROM 20181218 TO 20181219;REEL/FRAME:048286/0055") is all that is indexed. Recovering the correspondent of record requires a direct Patent Assignment Search query (or the recorded PDF wrapper) at https://assignmentcenter.uspto.gov/ for reel 048286 / frame 0055 — I could not pull that field through web search. Note that Endress+Hauser's own German filings in this family name an in-house attorney (cf. Andres, A., c/o Endress+Hauser) as the firm representative — but that is the European prosecution representative, not necessarily the US assignment correspondent, and I will not conflate the two.
  • Context: Internal capture — employment/inventor assignment to the applicant, executed in connection with US national-stage entry of PCT/EP2017/067824. Not a sale, not a fire-sale, not a transfer to an asserter.

No later links exist. Subsequent legal events are prosecution/grant/administrative only: pre-grant publication (2019-08-08), grant (2021-11-23), maintenance-fee reminder (2025-07-14), and lapse for failure to pay maintenance fees (events dated 2025-12-29 and 2026-01-20; effective date 2025-11-23). A fee lapse is an administrative event, not an ownership transfer.

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Timeline diagram

timeline
    title Ownership of US 11181432
    2016 : Priority filing DE 10 2016 114 846
    2017 : PCT filed by Endress Hauser
    2018 : Inventors execute assignment to Endress Hauser
    2019 : Assignment recorded reel 048286 frame 0055
         : US pre-grant publication
    2021 : US patent issued
    2025 : Maintenance fee lapse

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NPE / troll-pattern signals

Additional anti-signal worth recording: the patent was never asserted, and it lapsed for non-payment of maintenance fees effective 2025-11-23 — behavior inconsistent with an entity holding the patent for assertion.

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Verdict

Insufficient data — but note this is a rubric artifact, not genuine ambiguity. Under the forced-choice rubric, "Insufficient data" is the only bucket that fits a chain consisting of only the original assignment (reel 048286/0055, executed 2018-12-18/19, recorded 2019-02-07), since there is no litigation to support "operating-company assertion" and no defensive aggregator to support "defensive/non-asserting." Substantively, the evidence affirmatively shows no NPE activity whatsoever: a single inventor-to-operating-company assignment to Endress+Hauser SE+Co. KG, no shell entity, no known asserter, no cascading transfers, no pre-suit transfer, no bankruptcy, and an unasserted patent that lapsed for non-payment in late 2025. The chain simply terminates at the original operating assignee.

Verify directly (reel 048286 / frame 0055, and the absence of any later recording) at the USPTO Patent Assignment Search: https://assignmentcenter.uspto.gov/ (backup index: https://assignment.uspto.gov/patent/index.html). A direct query is also the only reliable way to recover the correspondent of record for that single assignment, which my sources could not surface.

I'll build on the bibliographic work already completed and now focus specifically on the prior-art citation set for US 11,181,432. Let me verify the key references.

I now have strong detail on several references. Let me verify the remaining key citations — the Endress+Hauser family prior art and the Rosemount/Siemens/Yokogawa/ABB items.

Scope and ground truth

Per the operating rule, I interpreted the identifier literally as US 11,181,432 and did not substitute similar numbers. The specific patent is confirmed by the authoritative full text supplied and corroborated by Espacenet/Google Patents:

• US 11,181,432 B2 — "Differential pressure measurement arrangement and method for identifying blocked differential pressure lines"
• Assignee: Endress+Hauser SE+Co. KG · Inventors: Long Yang, Max Jehle, Davide Parrotto
• Appl. 16/323,967 (PCT/EP2017/067824), filed 2017-07-14 · Priority: DE 10 2016 114 846.6 (2016-08-10) · Granted 2021-11-23
• 16 claims; independent claim 1 (apparatus) and claim 4 (method)

This section builds on the bibliographic/summary sections already generated and does not repeat them. It is confined to the prior-art citation set on the face of US 11,181,432.

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Critical framing before the reference-by-reference analysis

The user asks which claim(s) each reference "potentially anticipates under 35 U.S.C. § 102." I have to be candid about a structural point:

Anticipation requires that a single reference disclose every element of a claim, arranged as in the claim. The point of novelty in US 11,181,432 — the element the specification itself says solves the problem posed by its own earlier work — is the pre-diagnosis validation gate: capture a set of DP values → test whether the arrangement/process is in a diagnosis-enabling state → if not, discard (delete/overwrite) and re-capture, and repeat → only if yes, run the blockage diagnostic. Independent claims 1 and 4 each close on the definitional limitation that the diagnosis-enabling state = the arrangement is stable, and stability = the captured values fall within a first range at a predefined frequency.

None of the cited references discloses that combination. Consequently, strictly under § 102, none of the citations below anticipates independent claim 1 or 4. They are, with one exception (the Applicant's own earlier family art), § 103 obviousness references that supply the diagnostic function element or the statistical-range sub-features. I flag this for every entry rather than overstate § 102 reach.

Caveat on completeness: my search-step budget expired before I could retrieve full text for US 6,119,047 A, US 6,532,392 B1, DE 10 2006 004 582 A1, JP 2007-292733 A, DE 10 2004 058 424 A1, CN 105378451 A, and CN 102989074 A. For those, descriptions rest on the titles/abstracts in the authoritative citation list (noted individually). Everything else is grounded in retrieved text.

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The citation set (union of the two citation tables on the patent)

A. Directly relevant prior art

1. US 9,683,876 B2 / DE 10 2013 110 059 A1 — Endress+Hauser (family citation)

• Full citation: DE 10 2013 110 059 A1, "Differential pressure measuring arrangement with differential pressure lines and method for detecting clogged differential pressure lines"; US counterpart US 9,683,876 B2.
• Dates: DE filed 2013-09-12, published 2015-03-12; US 9,683,876 granted 2017.
• Description (verified from DE/US text): DP transducer with first/second DP lines into two pressure inlets, a temperature sensor, and a processing unit that determines a significant correlation between a change in the temperature signal and the DP signal and treats it as an indication of a clogged DP line (positive correlation ⇒ first line; negative ⇒ second line). It also analyzes noise/fluctuation of the DP signal. This is the art the '432 specification names as the baseline whose weakness (false/unsignificant diagnosis when the arrangement/process is in an unsuitable state) motivated the invention.
• Claim(s) implicated: Supplies the "differential pressure transducer + first/second differential pressure lines + inlets" structure of claims 1 and 4, and the "diagnostic function to determine whether a differential pressure line is blocked" step d) of claim 4 (the '432 specification expressly says step d) may "carry out the method described in DE 10 2013 110 059 A1").
• § 102 assessment: Does not anticipate claims 1 or 4 — it lacks the (a)–(d) gating loop and the stability/first-range definition. It is the primary § 103 starting reference and is the closest single-item art for the generic DP-line blockage-diagnosis concept.

2. US 6,119,047 A and US 6,532,392 B1 — Rosemount Inc. (Eryurek)

• Full citation: US 6,119,047 A and US 6,532,392 B1, both titled "Transmitter with software for determining when to initiate diagnostics."
• Dates: priority 1996-03-28; US 6,119,047 published/granted 2000-09-12; US 6,532,392 published/granted 2003-03-11.
• Description: (from citation title/abstract; full text not retrieved) A process-variable transmitter with software logic determining when to initiate diagnostics — i.e., gating diagnostic execution on a condition rather than running it unconditionally. This is conceptually the nearest Rosemount art to the "check whether the arrangement/process is in a state that allows a diagnosis before running the diagnostic" idea.
• Claim(s) implicated: Bears on the timing/initiation concept underlying steps b)–c) of claims 1 and 4.
• § 102 assessment: Does not anticipate claims 1 or 4 on the present record. To anticipate, it would have to disclose the delete/overwrite-and-re-capture loop and the stable-state = first-range-at-predefined-frequency definition; nothing retrieved shows that. Treat as § 103 material for the "when to initiate diagnostics" motivation. (Verified only to title/abstract level — flag for full-text pull.)

3. US 2016/0054162 A1 — Schlumberger Technology Corp.

• Full citation: US 2016/0054162 A1, "Methodologies and Apparatus for The Recognition of Production Tests Stability" (GB 2531882 B; US 10,309,816 divisional).
• Dates: priority 2014-08-21/22; published 2016-02-25.
• Description (verified): Multiphase flowmeter (with a differential-pressure transmitter across a Venturi) plus a computer that segments flowmeter data into time blocks and analyzes them in time and frequency domains to determine automatically whether a production test is "stable" — using probability-density/kernel-density estimates and variance thresholds; identifies stable periods "without analyst intervention."
• Claim(s) implicated: Directly relevant to the "check whether the process has no significant change" limitation of claims 2, 10, and 11, and to the general notion of quantitatively deciding process stability before trusting a measurement.
• § 102 assessment: Does not anticipate claims 1 or 4 — it is not about DP-line blockage at all, has no discard/re-capture loop, and its "stability" test is time/frequency-domain based rather than "values within a first range at a predefined frequency." It is strong § 103 art against the process-stability dependent claims (2, 10–15) and the broad concept of gating on stability.

4. US 6,654,697 B1 — Rosemount Inc. (Eryurek et al.) — also cited as US 2002/0029130 A1 (Eryurek) and CN 1185841 A / CN 1514928 A family

• Full citation: US 6,654,697 B1, "Flow measurement with diagnostics" (US 2002/0029130 A1 "Flow diagnostic system"; CN 1185841 A; CN 1514928 A).
• Dates: priority 1996-03-28; US 6,654,697 granted 2003-11-25.
• Description (verified): A DP flow meter that diagnoses the condition of its primary element and impulse lines. A difference circuit outputs sensed DP minus a moving average; a calculate circuit computes (i) a "trained output" of historical data obtained during an initial training time and (ii) a "monitor output" of current data during normal operation, and a diagnostic circuit generates a condition output from trained-vs-monitor data.
• Claim(s) implicated: The train-once-in-a-known-good-state then compare current data against the trained baseline architecture maps onto the "capture a second set of DP values while the process is in a stable state (e.g., at initial commissioning) and use its standard deviation as the first range" of claims 5, 6, and 9.
• § 102 assessment: Does not anticipate claims 1 or 4 — no state-gating loop, no deletion/overwrite. Best characterized as § 103 art, and as the clearest anticipation-type disclosure for the statistical baseline sub-feature that claims 5/6/9 add (but those are dependent claims carrying the independent-claim limitations, so no standalone § 102 hit either).

5. US 2014/0025318 A1 / CN 103575466 A — Azbil (Yamatake) Corporation

• Full citation: US 2014/0025318 A1, "Pressure guiding tube blockage diagnosing device and blockage diagnosing method" (CN 103575466 A; related US 8,453,517 B2, US 8,850,870 B2).
• Dates: priority JP 2012-159329 (2012-07-18); published 2014-01-23 (CN 2014-02-12).
• Description (verified): Diagnoses pressure-guiding-tube (impulse-line) blockage by partitioning a time series of pressure/DP data into intervals, computing a "feature quantity" of fluctuation, smoothing it, and evaluating a change rate; evaluation uses a stored reference characteristic "μ ± 3σ" of normal data to decide whether blockage state has changed.
• Claim(s) implicated: Bears on the statistical-range limitations — the "triple standard deviation" second range of claims 3 and 14, and generally the use of an earlier normal-data band as the reference.
• § 102 assessment: Does not anticipate claims 1 or 4 — no diagnosis-enabling gate, no discarding/re-capturing, and its μ±3σ band is applied to a change-rate indicator, not to "the first set or new set of DP values being within a first range at a predefined frequency." § 103 art against claims 3/14 and against the general statistical-threshold approach.

6. US 5,680,109 A — The Foxboro Company

• Full citation: US 5,680,109 A, "Impulse line blockage detector systems and methods" (WO 97/48974).
• Dates: filed 1996-06-21 (App. 08/669,901), granted 1997-10-21.
• Description (verified): DP sensor on high/low impulse lines, each with an absolute-pressure sensor; a processor extracts the noise variance of the absolute-pressure signal and a comparator indicates blockage when the variance falls below a threshold.
• Claim(s) implicated: The "diagnostic function to determine whether a differential pressure line is blocked" step d) of claims 1 and 4.
• § 102 assessment: Does not anticipate claims 1 or 4 — it is a pure blockage-detection technique with no pre-diagnosis state check or re-capture loop. Foundational § 103 art for the diagnostic-function element.

B. Other cited patent documents (diagnostic-function or peripheral art)

(CN 1185841 A and CN 1514928 A are Rosemount family members grouped under entry 4 above; US 2002/0029130 A1 is likewise grouped with US 6,654,697.)

C. Non-patent citations

• International Search Report, PCT/EP2017/067824, WIPO, dated 2017-10-09 (the ISR for this application's PCT — identifies the examiner-cited art; not itself prior art).
• Search Report, German Application 10 2016 114 846.6, German Patent Office, dated 2016-11-15 (the DE search report; the "Stand der Technik" it lists — DE 10 2006 004 582 A1, US 6,532,392 B1, US 6,654,697 B1, US 5,680,109 A — matches entries above).
• Liguo Gao et al., Energy-dispersive X-ray fluorescence method, Chengdu University of Science and Technology Press, Apr. 1998, pp. 187–190 — recorded as a non-patent citation with "concise explanation of relevance." On its face this text concerns X-ray fluorescence metrology, not DP-line diagnostics. I flag this as an apparent subject-matter mismatch and cannot explain its citation on the present record; it does not bear on any claim's patentability and I would not treat it as § 102 art without the examiner's stated relevance.

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Bottom line on the prior art

Most relevant single reference: the Applicant's own earlier DE 10 2013 110 059 A1 / US 9,683,876 B2 (Endress+Hauser) — it supplies the DP-transducer/dual-DP-line hardware and the blockage-diagnostic function that claim 1/claim 4 step d) may invoke, and the '432 specification expressly frames the invention as curing its weak/diagnosis-unsuitable-state behavior.

Most relevant to the actual point of novelty (the gating concept): US 6,119,047 A / US 6,532,392 B1 ("determining when to initiate diagnostics") for the timing/initiation idea, and US 2016/0054162 A1 (Schlumberger "recognition of production tests stability") for the process-stability gate. Neither, on the present record, discloses the delete/overwrite-and-re-capture-then-repeat loop or the specific "within a first range at a predefined frequency" stability definition that the independent claims require.

Overall § 102 conclusion: No cited reference — patent or non-patent — anticipates independent claim 1 or claim 4. The citation set is a § 103 obviousness set assembled against (i) the generic DP-line blockage-diagnosis step and (ii) the statistical-range/threshold sub-features carried by dependent claims 2–3 and 5–15. Any validity attack would rest on combinations (e.g., a Foxboro/Rosemount blockage detector + a Rosemount "when to initiate diagnostics" or Schlumberger "stability recognition" teaching), not on a single anticipatory reference.

Two honesty flags carried forward: (1) I could not retrieve full text for US 6,119,047, US 6,532,392, DE 10 2006 004 582, JP 2007-292733, DE 10 2004 058 424, CN 105378451, or CN 102989074 — those § 102 characterizations are provisional pending full-text review, though the citation titles/abstracts give no indication any of them contains the missing gating loop. (2) I did not reach USPTO Patent Center/Global Dossier directly; the citation and date data are taken from the authoritative patent text supplied (Google Patents rendering) with Espacenet corroboration.

I'll ground this analysis in the prior-art references listed on the patent page, and supplement with targeted lookups on the key references' disclosures.

Let me pull the two most directly on-point references: the admitted baseline (DE 10 2013 110 059 A1 / US 9,683,876 B2) and the Rosemount flow-diagnostics family.

Obviousness Analysis — US 11,181,432 B2 under 35 U.S.C. § 103

Patent under analysis: US 11,181,432 B2, "Differential pressure measurement arrangement and method for identifying blocked differential pressure lines" (Endress+Hauser SE+Co. KG; Yang, Jehle, Parrotto; filed 2017-07-14; priority DE 10 2016 114 846.6, 2016-08-10; issued 2021-11-23).

Prior art relied upon — the references listed in the "Citations," "Patent Citations," "Family Cites Families," and "Non-Patent Citations" sections of the patent page, plus the reference admitted in the specification:

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I. Governing standard and level of ordinary skill

Under Graham v. John Deere and KSR Int'l v. Teleflex, the question is whether the claimed subject matter as a whole would have been obvious to a person of ordinary skill in the art (POSITA) at the critical date (Aug. 10, 2016), given the scope and content of the prior art, the differences between the prior art and the claims, and any objective indicia.

POSITA here would be a controls/instrumentation engineer with a bachelor's degree in electrical, mechanical, or chemical engineering and roughly 2–5 years' experience with industrial differential-pressure transmitters, process diagnostics, and routine statistical signal analysis (means, standard deviations, thresholding, run-time process-condition monitoring). This is a mature, crowded art: all of the cited references sit in the process-instrumentation diagnostic space, and several are the applicant's own or its direct competitors'.

Two threshold observations, flagged up front:

1. The reference designators "US 6,119,047," "US 11,181,432," etc. are read literally per the operating rules. "DE 10 2013 110 059 A1" and "US 9,683,876 B2" are the same Endress+Hauser disclosure — the specification of US 11,181,432 itself calls the German application the starting point, so E+H '876 is admitted prior art.
2. The claims contain a genuine logical-polarity defect that affects claim construction (see §VI). Claims 10 and 16 recite "no significant change" but define it as the average value being outside the second range — the opposite of the intended meaning. Any §103 conclusion must be read subject to that construction ambiguity; it does not, however, change the outcome because the underlying function (a second, mean-based process-change gate) is what the art supplies.

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II. The invention's point of novelty

Stripped to essentials, US 11,181,432 does not claim a new blockage-detection physics. Its independent claims 1 and 4 claim:

• conventional DP-transmitter hardware (transducer + two DP lines to two inlets) — literal to the FIG. 1 embodiment and to every cited reference;
• a diagnostics unit that (a) grabs a batch of DP values, (b) decides whether the arrangement/process is in a diagnosis-enabling state, (c) if not, captures a fresh batch and deletes/overwrites the old one, looping, and (d) if so, runs a blockage diagnostic on the retained batch; and
• a closing definitional limitation: the enabling state is the arrangement being in a stable state, where stability is defined as the captured values falling within a first range at a predefined frequency.

The single point of departure over E+H '876 is therefore the data-admission gate: a pre-diagnostic quality/stability screen with discard-and-reacquire looping. That is where the obviousness contest is decided.

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III. Element-by-element mapping of claim 1 (apparatus)

There is no element of claim 1 for which the page's prior-art record is silent. Claim 4 (method) is the same disclosure viewed as process steps and is disposed of identically.

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IV. The dispositive combinations

Combination A (primary): E+H '876 + Rosemount '047 + Schlumberger '162

Where each reference is applied. E+H '876 supplies the entire hardware claim and the diagnostic function of step (d). Rosemount '047 supplies the pre-diagnostic gate — a transmitter "with software for determining when to initiate diagnostics," in which the reference/trained values are only generated once the process is determined to be stable, and in which the event output is produced "when the process has stabilized after initialization." Schlumberger '162 supplies the quantitative form of the gate — segment data into blocks, determine stability against pre-defined variance thresholds, and identify the stable periods on which a measurement conclusion may be based.

Why a POSITA would combine them. Motivation is explicit and comes from two independent directions:

1. The problem is stated in the primary reference itself. E+H '876's own specification works through a Bayesian reliability calculation and concludes that a fluctuation-based detection has only a P(V|F+) ≈ 1/3 chance of being a true plugging event — i.e., the reference itself teaches that its diagnostic is unreliable in isolation and expressly proposes combining independent tests to raise reliability from 1/3 to 5/6. A POSITA seeking to "increase reliability with respect to determining a blocked differential pressure line" (the stated aim of US '432) is directed by E+H '876 straight to the idea of adding a corroborating/reliability layer to the diagnosis.
2. The specification of US '432 concedes the gap. It states that the E+H '059 approach "has weaknesses with regard to the significance of the differential pressure line to be determined when the differential pressure measurement arrangement and/or process is or are in a state unsuitable for determining a blocked differential pressure line." An applicant's own statement that the starting art fails precisely because it diagnoses under unsuitable conditions is a near-textbook articulation of the problem that the claimed gate solves — and of why the solution was obvious to try.

Same field, same problem, known technique. All three references are process-instrumentation diagnostics. Rosemount '047 and the '392/'697/'130 family are pressure/flow transmitter diagnostics — the identical device class. Schlumberger '162 uses differential-pressure data as one of its monitored signals. Under KSR, where a technique (statistical data-validity gating) has been used to improve one device, "the use of the same technique to improve similar devices is necessarily obvious." Rosemount '047 already teaches the learn-while-stable, then diagnose workflow; applying it in front of the E+H '876 correlation diagnostic is a combination of prior-art elements according to known methods, yielding no more than the predictable result of fewer false diagnostics.

Combination B (alternative, entirely within the blockage-diagnostic art): E+H '876 + Foxboro '109 (+ Azbil '318)

Foxboro '109 discloses the complete architecture claimed in claim 1 save for the gate: DP sensor on HP/LP impulse lines, data acquisition, computation of a noise/variance value, comparison to a threshold, and blockage indication. Azbil '318 and its companion Technical Review paper disclose the stability-baseline technique with particular clarity: establish the normal-condition statistical baseline (mean and standard deviation) by monitoring a properly-operating process, then flag a fault when the statistic departs from the baseline — and set the thresholds from observed normal operation. Combining Foxboro '109's variance-based blockage detector with Azbil's statistical baseline (or with Rosemount '047's "trained values obtained by determining that the process is stable") yields the claim-1 subject matter. Here the art is squarely within impulse-line blockage detection, so the "analogous field" objection is unavailable to the patentee.

The closing limitation ("first range at a predefined frequency")

The final limitation is the weakest point of the claims as a distinguishing feature. The specification itself states that 68% is the "preferred" predefined frequency and that the first range is μ ± σ — that is simply the empirical (68-95-99.7) rule for a normal distribution. Determining whether ~68% of samples fall within one standard deviation of the mean is a conventional statistical stability check, and Rosemount '047 explicitly discloses "generating the statistical parameters" from stable-period data and applying rules to them. A POSITA would recognize the 68%/±1σ criterion as an arbitrary-but-conventional selection among a small number of known stability metrics; under KSR, "when a work is available in one field…, design incentives and other market forces can prompt variations of it," and a predictable, finite set of statistical thresholds is obvious to try.

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V. Dependent claims

The dependent claims add only statistical parameter choices and buffer-management mechanics, all of which are conventional and disclosed in the cited art. They therefore do not impart patentability over Combination A.

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VI. Construction caveat affecting this analysis

Claims 2 and 10 (and the corresponding specification passages) use contradictory polarity. Claim 2 defines a "significant change" as the average being outside the second range — internally coherent. Claim 10, however, defines "no significant change" as the average being outside the range, which is the inverse of the intended test and of the specification's own description (a return to step a) occurs when the average is not within the range). For §103 purposes I have construed both claims as covering the mean-valued, second-range process-change gate that the specification describes. Even under the patentee's most favorable construction, that gate is disclosed by Rosemount '047 and Schlumberger '162; the ambiguity therefore does not rescue the claims.

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VII. Counterarguments and objective indicia

Likely patentee arguments and responses:

1. "The references are from different fields / non-analogous art." Schlumberger '162 is oil-and-gas production testing, but it operates on differential-pressure flow data and addresses the same problem — deciding whether a measurement interval is stable enough to be trusted. Under KSR and In re Bigio, references addressing the same problem are analogous even across industries. Moreover, Combination B (E+H '876 + Foxboro '109 + Azbil '318) stays entirely within impulse-line blockage detection, so the non-analogous-arts defense fails as to at least one complete combination.
2. "The references do not teach discarding/deleting the data and repeating the determination." Discarding unstable data and waiting for a valid window is the express operation of Rosemount '047's stable-period training and Schlumberger '162's stable-block identification. "Delete or overwrite" is also an inevitable consequence of a continuously-fed data buffer — and the specification itself says the buffer is "preferably a ring memory," which overwrites by definition. That is the epitome of a predictable, design-choice limitation.
3. "The 68% frequency within ±1σ is not taught." It is the elementary empirical rule for a normal distribution; the specification presents it as a mere preference. A finite, well-known set of statistical thresholds is obvious to try.
4. "Secondary considerations." No evidence in this record of unexpected results, commercial success, long-felt-but-unsolved need, industry praise, licensing, or copying. Notably, the DE and EP counterparts were withdrawn/the PCT ceased, and US 11,181,432 lapsed for non-payment of maintenance fees effective 2025-11-23 — the family was not pursued to commercial assertion. These facts are consistent with low commercial weight but are not affirmative evidence of non-obviousness; I flag them as context only, not as a legal conclusion.

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VIII. Conclusion on obviousness

Claims 1 and 4 (and their dependent claims) would have been obvious under 35 U.S.C. § 103 at the August 10, 2016 critical date, over:

• Primary: E+H '876 (US 9,683,876 B2 / DE 10 2013 110 059 A1 — admitted prior art) in view of Rosemount '047 (US 6,119,047), further in view of Schlumberger '162 (US 2016/0054162 A1) and, optionally, the Azbil '318 statistical-index teachings; or
• Alternative: E+H '876 in view of Foxboro '109 (US 5,680,109) and Azbil '318.

The sole substantive addition over the admitted baseline — a pre-diagnostic stability gate that discards invalid data and re-acquires — was a known technique (learn-the-stable-process-then-diagnose, with statistical thresholds) applied to the same device class to solve the very reliability problem the primary reference itself identified. The result (fewer false plugging diagnoses) was predictable, and the claims' only narrowing features are conventional statistical parameters and buffer mechanics.

Strength of this opinion: Moderate-to-high on the element mapping (every limitation is disclosed in the cited set) and on the motivation rationale (the primary reference and the patent's own specification both articulate the problem the gate solves). It would be strengthened by full-text verification of the specific claim language of Rosemount '047 and Schlumberger '162's independent claims, which I have not reviewed line-by-line.

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Sourcing and confidence notes

• Grounded in the supplied authoritative text: the claim text, specification, family, citations, and legal-status events of US 11,181,432, including the express admission that "the approach described in DE 10 2013 110 059 A1 has weaknesses… when the differential pressure measurement arrangement and/or process is or are in a state unsuitable for determining a blocked differential pressure line."
• Grounded in retrieved prior-art text: E+H '876 (https://patents.google.com/patent/[US9683876B2](/patent/US9683876B2)/en; https://patents.justia.com/patent/[9683876](/patent/9683876)), US 6,119,047 (https://patents.google.com/patent/US6119047), US 5,680,109 (https://patents.google.com/patent/US5680109), US 2016/0054162 A1 (https://patents.google.com/patent/US20160054162A1), US 2014/0025318 A1 / US 8,850,870 and Azbil Technical Review 2016 (https://www.azbil.com/jp/corporate/pr/library/review/pdf/2016_04_5.pdf), and the Rosemount PowerGen/2000 diagnostics paper (https://www.idc-online.com/technical_references/pdfs/instrumentation/UTILIZING_ADVANCED_MEASUREMENT_DIAGNOSTICS.pdf).
• Not verified: the full claim sets and complete specifications of Rosemount '047/'392/'697/'130, Schlumberger '162, and Azbil '318 were not read in full; the mapping above rests on their abstracts, summaries, and the specific passages quoted. Also unverified is whether any specific office action (US or German) ever articulated this combination — the German search report cited US 6,532,392, US 6,654,697, US 5,680,109, and DE 10 2006 004 582 A1, which is suggestive that these were considered closest art, but I did not retrieve the associated office action or its reasoning.
• Per the operating rules, all identifiers are interpreted literally; I have not substituted any similar patent number.