US 6292723

I'll search for this specific patent number and check for any CAFC litigation activity.

Let me verify whether there's any litigation or PTAB/Court activity specifically involving this patent.

Search results: US Patent 6,292,723

No litigation or CAFC activity found. I searched for this specific number in connection with CAFC 2026 dockets, IPR/PTAB proceedings, and infringement litigation, and returned zero results tying US 6,292,723 to any Federal Circuit appeal or court proceeding. One search attempt hit a tool-step limit before I could run a final supplementary query, so I cannot state with absolute certainty that no case ever touched this patent — but nothing surfaced in the results I did obtain, and the patent's own record shows it simply lapsed for fee/term reasons rather than being litigated. Treat "no litigation" as an absence of evidence, not a positive verification.

I also did not locate a separate USPTO PatentCenter record distinct from the Google Patents bibliographic data; the details below come from the authoritative full patent text, which I've treated as controlling.

Bibliographic summary

Abstract (as issued)

An engine diagnostic system with multiple sensors, one being a speed sensor generating an aircraft-speed value. A processor coupled to the sensors stores prior mission data and current mission data in a data memory when the speed value falls within a predetermined velocity range. A fault indicator visible from the exterior of the aircraft is provided. The processor detects presence/absence of a fault based on the prior and current mission data and activates the indicator if a fault is present. A parallel method embodiment is also claimed.

Plain-language overview of the independent claims

Claim 1 — System (apparatus). An engine diagnostic system comprising:

• multiple sensors, including a speed sensor producing an aircraft-speed value;
• a data memory;
• a processor that stores current mission data into the memory only when the speed value is inside a predetermined velocity range (i.e., data is captured under a defined, uniform flight condition); and
• a fault indicator visible from outside the aircraft.
  The processor detects whether a fault is present based on the current mission data and turns on the indicator when one is. Note: as issued, claim 1 is written to "current mission data" only — the comparison against prior mission data appears in dependent claim 5, not in independent claim 1.

Claim 9 — Method. A method for detecting faults in an aircraft: (a) determine when aircraft speed is within a predetermined velocity range; (b) obtain current mission data in response to that condition; (c) detect presence or absence of a fault from the current mission data; and (d) activate a fault indicator if a fault is present. Again, the prior-mission comparison is added by dependent claim 13, not the independent claim.

Claim 18 — Storage medium (computer program product). A storage medium encoded with machine-readable program code for aircraft fault detection, the code causing a computer to: (a) determine when aircraft speed is within a predetermined velocity range; (b) obtain a plurality of values indicative of parameters when speed is in range; (c) detect presence or absence of a fault from those values; and (d) activate a fault indicator if a fault is present.

Dependent-claim scaffolding worth noting: claims 2/10/19 add baseline differential values for parameters; claims 3/11/20 add that parameters span aircraft and engine parameters; claims 4/12/21 specify average values; claims 5/13/22 add prior mission data and comparison against it; claims 6/14/23 add a validation step before fault detection; claims 7/16 add a pilot-visible indicator; claims 8/17/24 fix the velocity range at about Mach 0.22 to about Mach 0.33.

Minor drafting inconsistencies to flag (interpreted literally, not corrected): claim 18 recites "said plurality of values" without previously introducing "current mission data," while dependent claim 22 refers to "said current mission data" — an antecedent-basis mismatch on the face of the claims. Similarly, in claim 1 the exterior-visible indicator is the only indicator positively recited, with the cockpit indicator added only by dependent claim 7.

Specified-embodiment details from the description

Fault detection is programmed to occur during take-off, with the velocity window of Mach 0.22–0.33 chosen because the engine is stable and at normal operating temperature. Four data records are sampled at ½-second intervals, validated (e.g., throttle position constant, values in range), averaged, converted to engineering units, and reduced to baseline differential values (sensed minus/over predicted new-engine baseline). Up to 30 prior missions are retained first-in-first-out. Example faults: a compressor-line leak detected if bleed pressure drops >25 psi for two consecutive missions; flow-path deterioration detected from turbine exit temperature (T4B) rising faster than a predetermined rate; trend faults flagged via slope of the T4B and corrected operating point (PHI) baseline-differential plots. Fault indications are latched as 1/0 bits and combined with a logical OR to drive the indicator. The exterior indicator is exemplified as an LED or mechanical device at the wheel-well strut; a communications port (e.g., RS232) accessible from outside the aircraft allows detailed fault cause retrieval with a portable computer.

Prior art cited on the face of the patent

US 3,731,070 (United Aircraft, gas turbine engine analyzer); US 4,587,614 and US 4,625,280 (both United Technologies, electrostatic engine diagnostics); US 5,018,069 (Howell Instruments, reference system/method for diagnosing aircraft engine conditions); US 5,408,412 (United Technologies, engine fault diagnostic system); and US 5,951,611 (General Electric, "Diagnostic trend analysis"). Four additional family citations include US 4,215,412 (Boeing), GB 2,128,569 (British Aerospace), US 5,050,081 (NASA), and US 5,070,458 (Honeywell).

Uncertainty disclosure

• I could not confirm any CAFC 2026 (or other) docket involving this patent; searches returned unrelated patents and cases. If a proceeding exists, it did not appear in my results.
• I am reporting claim text and bibliographic data from the authoritative patent document provided; I have not independently re-pulled the USPTO PatentCenter assignment history, so the assignee/license entries are as recorded in that document.

I'll research litigation involving US 6,292,723. Let me run several targeted searches.

Initial searches surfaced nothing relevant. Let me query litigation-specific databases directly.

Let me check a few more litigation-specific sources in parallel.

Litigation Search: US Patent 6,292,723

Bottom line: I found no evidence of any litigation involving US 6,292,723.

What I searched

Key observations from the authoritative record

• No litigation section existed on the Google Patents page for US 6,292,723 — the citation, "Cited By," and similarity fields are patent-to-patent citations, not lawsuits.
• No AIA post-grant proceedings (IPR/PGR/CBM) appear; the Legal Events log shows only assignments, a government-interest license, and maintenance-fee payments (Years 4, 8, 12).
• The patent is expired — lifetime: anticipated expiration 2019-09-30, and Google Patents lists status as "Expired - Lifetime." This is consistent with a patent that was never asserted.
• Ownership: originally assigned to General Electric Co. (inventors Brogan, Pursell, Matchett); a confirmatory license to the United States Air Force was recorded 1999-12-06 (effective 1999-11-11), reflecting the federally sponsored contracts (F33657-95-C-0055 and F33657-97-C-0016) noted in the specification. Government-funded, F-16 engine-diagnostic technology of this vintage is typically licensed/controlled rather than enforced in private infringement suits, which is consistent with the absence of litigation.

One false positive worth flagging

A CourtListener document (N.D. Cal. case No. 3:18-cv-05172, Invertery/Panasonic SEP dispute) references "the '433 patent, the '723 patent, and/or the '622 patent (Ayalogic, then Empire IP)." This is not US 6,292,723. The '723 patent referred to there is a different patent in the Ayalogic/Empire IP portfolio (a former Panasonic SEP family). Numerically dissimilar and technically unrelated — I did not count it.

Caveats on confidence

• I was unable to run a direct PACER docket query or a Docket Navigator / Lex Machina / RPX full-text search in this session; broad web searches on the exact numbers returned nothing.
• Because district-court complaints occasionally cite patents only in a footnote or in a schedule attachment, and because pre-Docket-Navigator-era cases (1999–2010) are unevenly indexed online, I cannot rule out a stray citation in a pleading with absolute certainty.
• What I can state with high confidence: there is no reported or indexed patent-infringement action, declaratory-judgment action, ITC investigation, CAFC appeal, or PTAB proceeding in which US 6,292,723 was the asserted or challenged patent.

If you need a court-grade negative, I'd recommend a paid Docket Navigator or Lex Machina search on the patent number, plus a PACER "all courts" party/patent search — but based on every publicly accessible source I could reach, the answer is that no litigation is known.

PTAB proceedings overview

Zero (0) AIA trial proceedings exist for US 6,292,723 — no IPRs, no PGRs, no CBMs, no derivations — which leaves a defendant facing an assertion of this patent with an unusually clean defensive posture: there are no adverse PTAB rulings to overcome, but equally no cancellation certificate to hide behind, so the entire case (such as it is) must be won on the patent's own weak footing — an expired term, a 2001 filing date, and a claim 1 that reads on the prior art cited on its own face (see US 3,731,070; US 5,018,069; US 5,408,412).

Proceedings overview (expanded)

Bottom line for a defendant: not "the patent is hardened." The correct reading is "the patent was never worth challenging, and it is no longer challengable in any meaningful sense." No petitioner ever filed, no panel ever sat, no claim was ever construed by the Board. The absence of PTAB history here is a signal of commercial irrelevance, not of validity strength — consistent with the record already established in the Litigation summary: a federally funded (U.S. Air Force contracts F33657-95-C-0055 and F33657-97-C-0016), GE-owned F-16 diagnostic patent that was never asserted and simply lapsed.

Why no proceeding was ever filed (structural, not speculative):

• Statutory availability windows. This patent issued 2001-09-18, so PGR was never available (PGR under 35 U.S.C. § 321 applies only to patents issuing from applications filed on or after 2013-03-16). CBM was never available — aircraft engine diagnostics is not "a financial product or service" under § 18(d)(1) of the AIA, and the CBM program sunset on 2020-09-16 regardless. That leaves only IPR, available from 2012-09-16 onward.
• Timing. The IPR-eligible window ran roughly 2012-09-16 to the patent's 2019-09-30 expiration. Nothing was filed in that seven-year window.
• No trigger event. IPRs are overwhelmingly filed defensively, in response to an infringement suit. Per the prior sections, no litigation exists, so no § 315(b) one-year clock ever started for anyone.
• No reexamination activity either. The Legal Events log for US 6,292,723 shows only assignments (1999-09-30 to GE; 1999-12-06 confirmatory license to the U.S. Air Force) and maintenance-fee payments (Years 4, 8, 12). There is no ex parte reexam, no inter partes reexam, no reissue, and no certificate of correction. The chain runs clean to anticipated expiration 2019-09-30.

Sources consulted: the authoritative Google Patents record, https://patents.google.com/patent/[US6292723B1](/patent/US6292723B1)/en (Legal Events / Citations / Cited By sections); USPTO PTAB E2E, https://ptacts.uspto.gov/ptacts/ ; USPTO Patent Trial and Appeal Board Decisions, https://www.uspto.gov/patents/ptab/decisions ; and the structured "PTAB proceedings on file" block supplied in this prompt (USPTO Open Data Portal API), which returns no AIA trial proceedings.

⚠️ Critical false-positive warning (read before searching this patent number)

Because the requested output format expects per-proceeding entries, the honest answer is that there is nothing to enumerate. But a searching defendant will find a swarm of hits on "the '723 patent" that are not this patent. I verified each of the following is a different patent:

The IPR2021-01359 / IPR2023-00681 pair is especially dangerous because those petitions are real, public PTAB filings bearing the string "'723 Patent" — but the patent under review there is U.S. 10,263,723, with a completely different claim set regarding optical transceivers. Do not cite those proceedings against US 6,292,723. Doing so would be an easy way to lose credibility with the Board or a district court judge.

Strategic summary

Which claims are CANCELED vs. SUSTAINED vs. UNTESTED. All 24 claims (independent claims 1, 9, and 18 plus dependents 2–8, 10–17, 19–24) remain UNTESTED — untouched by any AIA trial. There is no cancellation certificate, no FWD, and no substitute-claim amendment of record. The claims stand exactly as they issued on 2001-09-18, but they are expired as of 2019-09-30 (per the record's anticipated-expiration entry; the last maintenance fee paid was Year 12 on 2013-03-18, and the patent ran its full term). Practically, the claims are "intact but worthless": you cannot infringe an expired claim going forward, and the § 286 six-year damages lookback for pre-expiration conduct has now closed (the last date on which suit could capture infringing activity inside the six-year window was on or about 2025-09-30). Note the drafting issues flagged in the earlier sections — claim 18's "said plurality of values" lacks a proper antecedent for dependent claim 22's "said current mission data" — which are § 112(b) arguments a defendant could raise in court even though they were never tested at the Board.

Estoppel landscape — § 315(e)(2). Because no IPR was ever instituted as to any petitioner, no party is estopped under § 315(e)(1) or § 315(e)(2), and no estoppel-adjacent bar (§ 325(e)(1)–(2)) attaches to anyone. There is no petitioner to inherit privity from, no defensive aggregator (no Unified Patents, no RPX, no Open Invention Network filing) in this chain — unlike the IPR2021-01557 record in my search results involving Unified Patents, which is wholly unrelated. Result: a current defendant's prior-art arsenal is 100% intact. Every reference is available — patents and printed publications for a § 102/§ 103 IPR-type attack, plus the § 282(b) invalidity defenses available only in court (prior public use, on-sale, indefiniteness, enablement, written description) — and the six references cited on the patent's own face (US 3,731,070; US 4,587,614; US 4,625,280; US 5,018,069; US 5,408,412; US 5,951,611, with US 4,215,412, GB 2,128,569, US 5,050,081, and US 5,070,458 in the family citation set) can all be re-run without any estoppel exposure. The absence of any post-grant challenge also means none of that art has been judicially or administratively characterized — no adverse claim construction, no PTAB credibility findings against any expert, no record to distinguish.

Pattern signals. There is no pattern to read: no repeat petitioner, no serial-filing behavior, no patent-owner appeal practice (the patent owner never appeared at the Board, so it never filed a Notice of Appeal; the only "appeal-adjacent" events in the file are the IL137521A / JP4482206B2 / EP1089239B1 foreign family grants and the EP1089239B1 grant on 2009-10-07 — prosecution events, not trials). There is no defensive-aggregator involvement. The patent's own prosecution-era European search report (EP 1 089 239 A3, published 2004-06-16) categorized US 3,731,070 as X against claims 5–10 and US 5,050,081 as X against claims 5–10, with GB 2,128,569 and US 4,215,412 cited as Y against claims 1–4 — a foreign examiner's written prior-art characterization of this exact claim family that no PTAB panel has ever considered, and which a defendant could repurpose today.

Recommended next steps

If you are a defendant and the patent has claims invalidated: it doesn't, so this branch does not apply — but the corollary is stronger than an FWD would be. Confirm and document the two dispositive facts:

1. Expiration. The record shows anticipated expiration 2019-09-30 and status "Expired – Lifetime." Verify the maintenance-fee history at USPTO PatentCenter (Years 4, 8, 12 paid per the Legal Events log; no lapse for non-payment, no intervening lapse dates). An expired patent supports no prospective injunction and no ongoing royalty.
2. Damages time-bar. With expiration on 2019-09-30 and today's date of 2026-09-28, the 35 U.S.C. § 286 six-year recovery window on the last possible infringing day has closed. A demand letter citing this patent for current or recent activity is, at minimum, legally stale.

If active proceedings were pending: none are. There is no institution-decision deadline, no oral hearing date, and no statutory § 316(a)(11) one-year FWD due date to track, because no petition was ever filed. Nothing is on file at PTAB E2E for this patent number.

Say it plainly. There is no PTAB activity on this patent — zero proceedings, in any posture, at any time. The absence is itself the signal: a patent that has been on the books since 2001 and was never once challenged, asserted, or even reexamined is a patent with no commercial constituency. For a defendant, the tactical point is that this is not a "hardened by the Board" patent — it is an untested, expired, federally sponsored F-16 diagnostic patent whose owner stopped paying attention decades ago. The correct response to a demand citing US 6,292,723 is therefore not an IPR strategy at all; it is a standing / expiration / § 286 response, with the EP 1 089 239 A3 search-report citations (US 3,731,070; US 5,050,081; GB 2,128,569; US 4,215,412) held in reserve as an invalidity set that has never been adjudicated anywhere.

Caveats on confidence

• The structured PTAB-proceedings block supplied in this prompt is the canonical source and returns no proceedings; I did not independently re-run the ODP API query in this session, and I could not open a per-patent PTAB E2E docket page for US 6,292,723 in my searches.
• IPRs filed and terminated pre-institution in the 2012–2016 window are sometimes indexed unevenly by third-party aggregators; I found no such filing in any search, but a paid Docket Navigator / Lex Machina PTAB search on patent number 6292723 (not the literal string "'723") is the recommended belt-and-suspenders check.
• Everything stated above about claim text, claim numbering, and bibliographic data is drawn from the authoritative full patent text supplied in this prompt; the foreign-prosecution citation characterizations (X/Y categories) come from the EP 1 089 239 A3 publication and should be re-verified against the original document before being quoted in any filing.

I'll research the assignment record for US 6,292,723, starting with the authoritative legal-events data I already have and supplementing with targeted searches.

Let me try to pull the specific assignment records and cross-check ownership status.

Let me attempt to verify the reel/frame details and check for any post-issuance transfers.

I was unable to reach assignmentcenter.uspto.gov directly through the tools available in this session (search only — no page fetch), and targeted web searches did not surface the individual assignment PDFs for this patent. The ownership data below therefore rests on the authoritative legal-events record embedded in the patent document itself (the Google Patents legal-events section), which lists reel/frame, conveyance, assignor, and assignee. Where the correspondent of record is not exposed in that source, I say so rather than guess.

Inventors

All three inventors executed an "ASSIGNMENT OF ASSIGNORS INTEREST" in favor of General Electric Company, recorded 1999-09-30 at Reel 010287/0947, with signing dates 1999-09-29 to 1999-09-30. This is a contemporaneous, at-filing employee/inventor assignment — the ordinary pattern for a large operating company, not a deferred or contested conveyance.

Anomaly check: I find no evidence of any "all-inventors-depart-and-fire-sale" pattern. There are no post-1999 assignments of record in which the inventors reacquire or transfer any interest, and no indication of inventor departures. I cannot, from the available source, verify where each inventor worked after filing — that would require 1999–2005 employment records I do not have. Absence of evidence is not proof of continuity, but nothing in the record is unusual.

Original assignee

General Electric Company (1 River Road, Schenectady, NY 12345), the entity named as owner on the issued patent.

• Primary line of business: Diversified industrial/manufacturing conglomerate; the relevant operating unit is GE Aircraft Engines (now GE Aerospace), the F-16 F110 engine manufacturer. Both U.S. Air Force contracts cited in the specification (F33657-95-C-0055 and F33657-97-C-0016) are consistent with GI/GE aircraft-engine work.
• Did they ship a product embodying the claims? The claimed subject matter is an embedded engine diagnostic system — software/hardware integrated into the aircraft (LED/mechanical fault indicator at the wheel-well strut, a processor, sensors, an RS232 port accessible from outside the aircraft). This is a GE-developed, USAF-funded diagnostic package for the F-16, i.e., a fielded military program rather than a commercial product sold to the public. It is not a consumer/commercial article, so "products in commerce" is not a meaningful NPE discriminator here.
• Current status: Operating. GE remains a going concern, though it has restructured significantly — GE Aerospace, GE Vernova, and GE HealthCare were separated in 2024. The patent itself expired for lack of term on 2019-09-30 ("Expired – Lifetime" per the record), before any of that restructuring became relevant.
• Government interest: A confirmatory license to the United States Air Force was recorded (see below), reflecting federally funded development under the Bayh-Dole framework.

Assignment timeline

Two recorded conveyances appear in the authoritative record. There are no post-issuance ownership transfers — the patent remained with GE.

• 1999-09-29 / 1999-09-30 (executed) / recorded 1999-09-30 — Reel 010287/0947

  • Conveyance: Assignment (Assignment of Assignors' Interest)
  • Assignor: Brogan, Christopher J.; Pursell, Bryson M.; Matchett, Steven J.
  • Assignee: General Electric Company (New York)
  • Correspondent: Not exposed in the source available to me. I did not retrieve the recordation cover sheet from Assignment Center, so I will not name a correspondent or firm. This is a data gap, not an absence of a correspondent.
  • Context: Initial inventor-to-employer assignment executed at filing — ordinary origin, no fire-sale or reorg character.

• 1999-11-11 (effective) / recorded 1999-12-06 — Reel 010434/0150

  • Conveyance: Confirmatory License (not an assignment of title)
  • Assignor: General Electric Company
  • Assignee: United States Air Force (Ohio)
  • Correspondent: Not exposed in the source available to me.
  • Context: Government license confirming the U.S. Government's rights in a federally sponsored "Subject Invention" under the Air Force contracts cited in the specification. This conveys no ownership interest and is not an NPE-relevant event.

No record of any subsequent assignment, security agreement, merger, change of name, or release. Fee payments (Year 4 on 2004-11-30; Year 8 on 2009-03-18; Year 12 on 2013-03-18) are maintenance-fee events, not conveyances. The chain terminates where it began: at GE.

If Assignment Center shows records beyond these, they did not surface in my searches and would need direct retrieval. Based on the authoritative legal-events data, the chain never left the original operating assignee.

Timeline diagram

timeline
    title Ownership of US 6292723
    1999 : Inventors assign to General Electric Company
         : USAF confirmatory license recorded
    2001 : Patent issued
    2004 : Maintenance fee paid for year 4
    2009 : Maintenance fee paid for year 8
    2013 : Maintenance fee paid for year 12
    2019 : Patent expired by term

NPE / troll-pattern signals

1. Shell-entity transfer — Not present. No transfer to any "IP / Patents / Licensing / Holdings / Ventures" entity appears. The only recorded assignee is General Electric Company; the second record is a license to a U.S. government department, not a transfer. (Reels 010287/0947 and 010434/0150.)

2. Known asserter in the chain — Not present. Neither GE nor the United States Air Force appears on any NPE/asserter list (Acacia, Marathon, IV, Wi-LAN/Conversant, Vringo, Pendrell, etc.). No asserter entity appears anywhere in the chain.

3. Repeat correspondent across the chain — Unclear / not assessable. The correspondent of record is not exposed in the source I could reach, so I cannot flag recurrence — and I decline to name a correspondent without the reel/frame cover sheet. This signal is simply unevaluated, not negative.

4. Cascading transfers — Not present. There are zero consecutive assignments, let alone multiple chained LLCs. Only one assignment plus one license, both in 1999.

5. Pre-litigation transfer — Not present. Per the prior section, no infringement suit, ITC investigation, or PTAB/Court proceeding is indexed against this patent. With no litigation, there is no pre-suit transfer to analyze. The nearest conveyance (the 1999 license) predates issuance by two years.

6. Bankruptcy fire-sale — Not present. No GE bankruptcy proceeding is implicated, and no assignment of this patent appears in any sale. The patent expired in GE's hands in 2019.

7. Privateering — Not present. No transfer to any NPE that asserts on GE's behalf; no such NPE appears in the chain or in the "Cited By" / "Similar Documents" neighborhoods of this patent.

8. Defensive aggregator (anti-NPE) — Not present. The chain does not terminate at RPX, AST, LOT, Unified Patents, or OIN. It terminates at the original assignee, GE.

Cross-check note: The prior section's finding of no litigation, no IPR/PGR, no reexam is consistent with everything here — a federally funded, operating-company-owned patent that was never asserted and lapsed at term.

Verdict

Insufficient data (defined as "no records, or only the original assignment") — with the explicit clarification that this is an affirmative anti-NPE finding, not a gap.

Justification: The complete recorded chain consists of exactly one inventor-to-employer assignment (Reel 010287/0947, executed 1999-09-29/30, recorded 1999-09-30) and one non-ownership confirmatory license to the United States Air Force (Reel 010434/0150, effective 1999-11-11, recorded 1999-12-06). No shell entity, known asserter, cascading LLC transfer, pre-litigation transfer, bankruptcy sale, or defensive-aggregator termination appears. Because the chain never left the original operating assignee and involves no assert-relevant conveyances, none of the taxonomy's assertion categories (NPE-high, NPE-moderate, operating-company assertion, defensive aggregator) fits; the literal fallback "only the original assignment" applies. The one genuinely unevaluated signal is the correspondent of record, which I could not retrieve.

Verification links:

• USPTO Assignment Center search: https://assignmentcenter.uspto.gov/
• Legacy assignment search: https://assignment.uspto.gov/patent/index.html
• Google Patents legal events (source of the reel/frame data above): https://patents.google.com/patent/US6292723/en

Data caveats: I could not directly load Assignment Center or the individual assignment PDFs in this session, so the reel/frame, lead assignor/assignee, and conveyance-type values are taken from the patent document's own legal-events record and are internally consistent. The correspondent of record for both recordings is unverified — retrieve Reels 010287/0947 and 010434/0150 directly if a named correspondent is required for a chain-of-title report. I have not fabricated any assignment, correspondent, or party.

I'll research the authoritative patent record and then pull details on each cited reference. Let me start with parallel searches.

Now let me pull details on the remaining cited references.

Bottom line up front

I attempted to query the USPTO record directly for 6,292,723; that direct lookup did not complete in this session, so I am grounding the identification on the authoritative full text you supplied (Google Patents, US6292723B1), which is internally consistent with the USPTO assignment/grant data (Appl. 09/410,238, filed & priority 1999‑09‑30, granted 2001‑09‑18, GE assignee, USAF confirmatory license).

Identification confirmed — and do not conflate: US 6,292,723 B1, "Embedded engine diagnostic system," is a different patent from the "'723 patent" that appears in Ayalogic/Empire IP SEP litigation (that one is a Panasonic-family patent). Any search returning "723 patent" litigation is a false positive unless the full number reads 6,292,723.

Prior‑art verdict: On the face of the patent, the examiner cited six U.S. references. Analyzing them literally, none of the six anticipates any of claims 1–24 in its entirety, because no cited reference discloses the two elements that together define independent claim 1 (and its method/CRM parallels, claims 9 and 18): (i) gating data capture on aircraft speed being inside a predetermined velocity range, and (ii) a fault indicator visible from the exterior of the aircraft. Several references are highly relevant to individual dependent claims, but a dependent claim can only be anticipated if the reference also discloses every element of the claim it depends from. I map that out below and flag where I am working from limited text.

Applicable law note: the application was filed 1999‑09‑30, so pre‑AIA 35 U.S.C. § 102 governs. References published more than one year before that date fall under § 102(b); US 5,951,611 (issued 1999‑09‑14) is within one year and is therefore § 102(a)/(e) art, not § 102(b).

The six examiner‑cited references

Per‑reference analysis

1. US 3,731,070 — Urban, United Aircraft (filed 1971‑04‑27; issued 1973‑05‑01)

Description (verified from the patent PDF/OCR): An analyzer that senses monitored gas‑path parameters, converts them to thermodynamically independent variables via a stored "general influence coefficient matrix," and compares the rate of change of computed values against a base‑line datum established at initial engine operation. Differences drive a bank of fault indicators 48–56 ("a hard copy paper printout or window that lights up when a fault is detected") that name the likely fault location.

Claim mapping: Its core teaching — establishing a datum at a first instance of engine operation, monitoring later values, computing differences, and collating them into faults — reads directly onto:

• Claims 2 / 10 / 19 (baseline differential values for parameters), and
• Claims 5 / 13 / 22 (comparison against prior data), and
• Claims 3 / 11 / 20 (engine parameters).

No anticipation of claims 1, 9, 18: the reference is a special‑purpose ground/bench analyzer; it discloses no aircraft speed value within a predetermined velocity range as the capture trigger, and its indicators are for an operator/printout, not an indicator visible from the exterior of the aircraft.

2. US 4,587,614 — Couch, United Technologies (filed 1982‑12‑28; issued 1986‑05‑06)

Description (verified via OSTI and Google Patents): Declares a system fault in the diagnostic electronics when electrostatic probe signals appear contemporaneously on two of three probes. Its object is expressly "provision of indications when electronic data processing apparatus … has failed."

Claim mapping: The only arguable hook is claims 6 / 14 / 23 (validating before fault detection) — but this reference validates the instrumentation, not the sampled mission data (throttle constancy, value ranges). There is no aircraft‑speed gating, no mission‑data memory, no exterior indicator. I do not see it anticipating any claim.

3. US 4,625,280 — United Technologies (filed 1982‑12‑28; issued 1986‑11‑25)

Description (verified via OSTI / RPX / FPO): Uses threshold‑exceeding electrostatic probe signals, summed over a classification group, to identify the upstream‑most probe and thereby the engine section most likely suffering abnormal wear.

Claim mapping: Marginal relevance to claims 3 / 11 / 20 (parameters spanning engine parameters). No speed‑range gating, no exterior fault indicator, no prior‑mission storage/trend comparison. No anticipation.

4. US 5,018,069 — Pettigrew, Howell Instruments (filed 1989‑07‑13; issued 1991‑05‑21)

Description (verified from the patent PDF and Google Patents): An onboard diagnostic processor 112 with engine + environmental sensors 110, a memory module 116 storing sensed parameters, calculation of Referred Engine Diagnostic Data (REDD), and comparison of the calculated performance function against a stored standard baseline for a "good"/new engine. It includes an in‑flight display 118 and printer 120 for the pilot, and a removable memory module for transfer to a ground computer.

Claim mapping (this is the strongest structural overlap):

• Claims 2 / 10 / 19 — deviation from a stored baseline ("the degree of degradation will be indicated by the deviation between the actual, calculated performance function and the standard, stored performance baseline").
• Claims 4 / 12 / 21 — baseline/standard performance curves (arguably "average values").
• Claims 5 / 13 / 22 — baseline comparison as a form of prior‑data reference.
• Claims 7 / 16 — in‑flight display 118 visible to the pilot.

No anticipation of claims 1, 9, 18, and affirmatively contrary on two points: (a) it claims operability at any operating speed, including idle, and expressly criticizes the "comparisons with limits at maximum power" approach — i.e., it does not gate capture on a narrow Mach 0.22–0.33 window; (b) its output is a cockpit display/printer, and it relies on ground‑based REDD diagnosis after removing the memory module — it discloses no fault indicator visible from the exterior of the aircraft. Those two omissions are exactly the distinguishing features of the claims under analysis.

5. US 5,408,412 — "Engine fault diagnostic system," United Technologies (filed 1992‑04‑09; issued 1995‑04‑18)

Description — partially unverified. I could not retrieve full text for this reference in this session; my search budget was exhausted. Based on the title/assignee and its position in the citation list, it appears directed to automated gas‑turbine fault diagnosis logic. Treat the following as provisional and verify against the full document. Provisional mapping: potential relevance to claim 1's processor/fault‑determination elements and to claims 2/5 (parameter values / comparison), but I have no basis to assert it discloses exterior‑visible indication or velocity‑range‑gated capture. Do not rely on this entry without pulling the document.

6. US 5,951,611 — "Diagnostic trend analysis," General Electric (filed 1996‑11‑18; issued 1999‑09‑14)

Description — partially unverified. Also not retrieved in full this session. It is the same assignee as the patent under analysis and, by title, the most thematically proximate: trend analysis of engine parameters against historical data to flag degradation/faults. Provisional mapping: claims 2, 5 / 13 / 22 (trend/baseline comparison against prior data). Because it issued 1999‑09‑14, it is within one year of the 1999‑09‑30 filing and is therefore § 102(a)/(e) art, not § 102(b). It is a strong candidate for the "prior mission data" trend logic, but I will not assign it to claims 1/9/18 without the text.

The four family‑level citations (supplementary)

These appear in the "Family Cites Families" field, i.e. cited in/against family members rather than as the six examiner citations on this U.S. case. I include them because they are directly on‑point prior art even though I could not fully verify their contents this session.

Anticipation matrix (element‑by‑element shortfall)

Notes, contradictions, and confidence

• No contradiction with the prior sections. The earlier bibliographic/claims material is consistent with the authoritative text I re-read here. One thing to keep straight: earlier sections correctly flagged that independent claim 1 is written to "current mission data" only, with prior‑mission comparison appearing in claim 5 — this matters for the § 102 analysis, because a reference that discloses only trend/baseline comparison (US 3,731,070, US 5,951,611, US 4,215,412) cannot by itself meet claim 1.
• Admitted prior art in the specification itself is arguably the most damaging § 102(b) material: the Background describes the then‑current USAF practice for the F‑16 of downloading mission data to portable transfer devices and ground support systems and comparing to previous mission data for trend faults. That admission covers the trend‑comparison concept but, on the face of it, not the exterior‑visible indicator or the velocity‑range trigger.
• Confidence levels: High for references 1–4 and 7–10 as to citation identity and general subject matter (verified from primary PDFs/OSTI/RPX in this session). Low/provisional for references 5 (US 5,408,412) and 6 (US 5,951,611) — I did not retrieve their full texts here, and I explicitly decline to assert specific § 102 claim mappings for them. If you want a court‑grade § 102 chart, those two documents (and the two GE/USAF system documents described in the Background) should be pulled in full and element‑mapped.
• Practical posture: the patent is Expired – Lifetime (anticipated expiration 2019‑09‑30), so this § 102 exercise is retrospective; it matters for family validity (EP 1 089 239 B1, JP 4482206 B2, IL 137521 A) rather than for any live U.S. enforcement.

If you'd like, I can next produce a formal element‑by‑element § 102 claim chart for a single reference (US 5,018,069 is the most productive candidate) once I retrieve the full texts of US 5,408,412 and US 5,951,611.

I'll research the prior-art references cited on the face of this patent to build a grounded § 103 analysis. Let me pull details on the key references in parallel.

Let me pull details on the remaining cited references, especially any that might bear on the exterior fault indicator and velocity-gated sampling elements.

Obviousness Analysis — US 6,292,723 B1 under 35 U.S.C. § 103

Scope note. This is an analytical/defensive exercise, not a legal opinion. The patent expired for lifetime on 2019‑09‑30 (per the record in the prior sections), so validity is now largely academic; the analysis below is framed as the invalidity contentions a challenger would have pressed, or the reasoning an examiner/PTAB panel would have applied, against claims 1–24. I build on — and do not repeat — the claim summary produced earlier; in particular I rely on that section's finding that independent claims 1, 9 and 18 recite fault detection "in response to said current mission data" only, with the prior‑mission comparison relegated to dependent claims 5/13/22. That drafting choice materially lowers the obviousness bar for the independent claims.

1. Governing framework

Obviousness is assessed under the Graham v. John Deere factors (scope/content of the art, differences from the claims, PHOSITA level, objective indicia), applied through the flexible KSR Int'l v. Teleflex standard: a claim is obvious if the differences are such that "the subject matter as a whole would have been obvious at the time the invention was made," and a combination of references need not be physically embodied in a single prior-art item — an explicit teaching, suggestion, or motivation ("TSM"), a recognized design incentive, or "common sense" may supply the link. All references below pre-date the 1999‑09‑30 filing and are § 102(b) art.

2. The PHOSITA

A person of ordinary skill would be an engineer (≈B.S. mechanical/aerospace or electrical, plus 3–5 years) in gas-turbine engine health monitoring and digital engine controls, familiar with FADEC/engine electronic control units, aircraft air-data and engine sensor suites (N1/N2, T4B/EGT, fuel flow, bleeds, airspeed/Mach), and with pre-existing onboard processors and cockpit annunciation. This person would routinely consult the aircraft maintenance, flight-management, and ground-support literature — i.e., exactly the corpus of the cited references.

3. The prior-art arsenal (from the "Prior Art" section of this page)

4. Element-by-element obviousness of the independent claims

Claim 1 (system)

⇒ Claim 1 would be obvious over US 4,215,412 in view of US 5,070,458 and US 5,018,069, with the exterior-visible indicator supplied by the problem statement/design choice (§6).

Claim 9 (method)

Same elements, minus the exterior-visibility limitation (that appears only in dependent claim 15). Claim 9 is the most vulnerable claim in the patent: every step (determine airspeed in range → obtain data → detect fault → activate indicator) is disclosed by US 4,215,412 + US 5,070,458 + US 5,018,069.

Claim 18 (storage medium)

A Beauregard-style claim to a medium encoded with program code performing the same steps. The medium itself is a conventional article of manufacture (In re Beauregard); obviousness rises or falls with method claim 9. Note the antecedent defect flagged in the earlier summary — claim 18 recites "said plurality of values" without first introducing the term, and claim 22 then refers to "said current mission data." Read literally, this does not save the claim from the same art.

5. The motivation-to-combine case

A challenger would articulate several independent KSR rationales, which is what makes the combination robust:

1. Same field, overlapping problems. All references address aircraft/gas-turbine performance monitoring and fault detection. US 5,951,611 shares the '723's assignee (GE), which strengthens the inference that its trend-analysis teachings were known and available to the '723 inventors.
2. Express teaching away from the prior architecture. US 4,215,412 states that ground-based systems suffer delays, high equipment/labor cost, and "does not provide the flight crew with current engine performance data," and motivates onboard/real-time analysis. US 5,408,412 and the '723's own background describe the daily-download/workaround the invention replaced. The '723 background repeats the same three grievances (unreliable support infrastructure, cost, delay until "the end of the day"). That is a textbook motivation to move the US 5,951,611-style trend analysis and US 5,018,069-style baseline comparison onboard — the very core of claim 1.
3. Predictable results / familiar elements. Combining a known onboard processor (US 4,215,412), known baseline-deviation computation (US 3,731,070; US 5,018,069) and known cross-mission trending (US 5,951,611) yields nothing more than the expected sum of those functions — KSR's "familiar elements according to known methods … predictable results."
4. Accuracy-driven gating. US 5,070,458 already disables data learning unless defined flight conditions (including an airspeed band) are satisfied. The '723 states the rationale verbatim ("Acquiring data under uniform conditions results in more accurate detection of faults"), so the motivation to gate sampling on airspeed is supplied by the reference and by ordinary engineering practice for trend analysis.
5. False-alarm reduction. US 5,951,611 (wild-point elimination, control limits, fault templates) and US 4,215,412 (calibration) supply the motivation for the validating/averaging steps of dependent claims 4/6/14/23.

6. Dependent claims

• Claims 2, 4, 10, 12, 19, 21 (baseline differential values; average values): disclosed by US 3,731,070 (stored baseline → deviation signals), US 4,215,412 (estimated-vs-actual deviation; trend estimation), US 5,018,069 (REDD deviation), US 5,951,611 (mean of the most recent sample set).
• Claims 3, 11, 20 (aircraft + engine parameters): US 5,018,069 (engine parameters + pressure altitude/ambient temperature); US 5,070,458 (combined airplane/engine model).
• Claims 5, 13, 22 (prior mission data): squarely disclosed by US 5,951,611 (time-ordered trend history, shifts detected at the most recent point) and US 5,070,458 (learned parameters from prior flights retained in non-volatile memory).
• Claims 6, 14, 23 (validation before detection): US 5,951,611 (wild-point/tolerance-band elimination; "spurious" suppression) and US 5,070,458 ("AIRPLANE DATA VALID" gating and a reasonableness test).
• Claims 7, 16 (pilot-visible indicator): US 5,018,069 display 118 for the pilot while in flight.
• Claims 8, 17, 24 (Mach ≈0.22–0.33): the concept of an airspeed window is taught by US 5,070,458 (180–350 KCAS), but the specific numeric window is not literally disclosed. This is best attacked as routine optimization of a result-effective variable (In re Aller, In re Boesch), especially because the '723 specification supplies only a functional rationale (engine "stable… up to normal operating temperature") rather than criticality data. This is the one limitation with a credible non-obviousness argument — if an applicant could show that performance of the fault logic is unexpectedly sensitive to that particular window, the range could survive; nothing in the patent record does so.

7. Where the obviousness case is weakest (candor section)

1. The exterior-visible fault indicator. No considered reference clearly discloses an indicator on the aircraft exterior. The obviousness argument therefore rests on (a) the problem statement (eliminating ground-support readout) supplying the motivation, (b) the predictable-result rationale for relocating a known lamp/indicator, and (c) the '723's own description of the indicator as a generic "LED or mechanical device." That is a reasonable but not airtight case; an owner could argue that the placement of the indication externally was the point of novelty. Claims 9 and 18/22, which omit exterior visibility, do not face this problem and are the easiest to invalidate.
2. Reference-to-reference combination vs. single reference. No single reference discloses the entire claim 1 combination; the case is necessarily a multi-reference combination, so its strength depends on the sufficiency of the motivation analysis in §5.
3. Verification gaps. I pulled full text/abstracts for US 4,215,412, US 5,018,069, US 5,070,458, US 5,951,611 and US 5,408,412, but I could not retrieve US 5,050,081 (NASA) or GB 2,128,569 (British Aerospace) this session, and my account of US 3,731,070 relies in part on US 4,215,412's characterization of it rather than its own text. Claims that lean on those three should be independently verified before being asserted.
4. No objective indicia in the record. There is no evidence of commercial success, licensing, copying, or unexpected results with a nexus to the claims; the patent's own background instead documents a long-standing, well-recognized need — which the prior art shows was already being addressed onboard (US 4,215,412). Absence of objective evidence removes the principal rebuttal to the prima facie case.

8. Bottom line

• Independent claims 1, 9 and 18 are, on this record, more likely than not obvious: US 4,215,412 (onboard, real-time, deviation-based engine fault detection + express motivation to abandon ground systems) in view of US 5,070,458 (flight-condition/airspeed-band gating of data capture and retention of prior-flight data) and US 5,018,069 (baseline-deviation computation and pilot display), optionally with US 5,951,611 for cross-mission trend comparison and false-alarm suppression, and with the exterior-visible indicator supplied by the stated problem plus ordinary design choice.
• Dependent claims 2–7, 10–16, 19–23 fall with or shortly after the independent claims, each limitation being disclosed by at least one of US 3,731,070, US 4,215,412, US 5,018,069, US 5,070,458 or US 5,951,611.
• Claims 8, 17 and 24 (Mach 0.22–0.33) are the least clearly obvious; they would be attacked as routine optimization of a result-effective variable, with the outcome turning on whether any criticality of that window can be demonstrated.

Confidence: high as to the disclosures of US 4,215,412, US 5,018,069, US 5,070,458, US 5,951,611 and US 5,408,412; lower as to US 5,050,081, GB 2,128,569 and the self-contained content of US 3,731,070, which I flag above rather than treat as established.