Invalidity dossier

US 6298292

Vehicle height adjust control apparatus and method

Current assignee: Toyota Motor Corp

Added 9/25/2026, 2:13:35 PM

At a glanceNo PTAB challengesNo litigation on fileAutomotive (A)

Active provider: DeepSeek · deepseek-v4-flash

Auto-generating section 1 of 2: Extensions…

Each section takes ~30-60s with web-search grounding. Keep this tab open — sections will fill in below as they complete.

Patent summary

Title, assignee, inventors, filing/issue dates, abstract, and a plain-language overview of the claims.

✓ Generated

I'll search for this specific patent number in the requested sources.

Let me run additional targeted searches to check USPTO records and any litigation involving this exact number.

US 6,298,292 B1 — Search Summary

Scope/sourcing note: I ran searches against the USPTO-oriented and general web, plus a CAFC-2026 docket search, specifically for the literal number 6298292. I did not gain direct access to USPTO PatentCenter/PAIR or an official CAFC docket system in this session — the bibliographic data below is corroborated by the authoritative full text of the patent supplied to me (Google Patents page for US6298292B1) and by a secondary aggregator hit. Treat legal-status and litigation points as unverified for the reasons in the "Uncertainty" section.


Bibliographic data

Field Value
Patent number US 6,298,292 B1 (US6298292B1)
Title Vehicle height adjust control apparatus and method
Application no. US09/166,097
Filing date 1998-10-05
Priority date 1997-12-18 (JP Application No. HEI 9-349119, filed 1997-12-18, incorporated by reference)
Issue/grant date 2001-10-02
Assignee Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corp) — original and current
Inventors Shoichi Shono; Atushi Sato (as spelled in the record; I am not normalizing this spelling)
Claims 12 (independent: 1, 5, 7, 11)
Status (per source) Expired – Lifetime; anticipated expiration 2018-10-05

Classification: B60G17/015, B60G17/016, B60G17/0164 (vehicle suspension; resilient suspensions with electronic regulating means responsive to specific motion/condition, mainly during accelerating or braking); indexing B60G2400/106, B60G2400/204, B60G2500/30.


Abstract (as published)

The patent describes a vehicle height adjust control apparatus/method that reduces switching noise from actuators and improves actuator durability. A microcomputer computes forward-backward acceleration from a vehicle-speed sensor signal. If that acceleration is at or below a first predetermined value, vehicle height deviation from target is corrected by a normal operation. If it is greater than the first value but not greater than a second (larger) value, the start determination for height adjustment is prevented. If it exceeds the second value, height adjustment is suspended. This lets the second threshold be set large (reducing suspend/restart cycling) while still reliably blocking new adjustments when warranted, thereby reducing total actuator switching.


Independent claims in plain language

Claim 1 (apparatus). A vehicle height control apparatus with:

  • an actuator that can change vehicle height;
  • a vehicle height detector;
  • a start determiner that decides height adjustment should start when the deviation of detected height from a target height reaches a predetermined level;
  • a vehicle height changer that drives the actuator so detected height becomes substantially equal to the target when that start determination is made;
  • a physical-quantity detector sensing a vehicle motion quantity that changes vehicle posture — expressly "other than the vehicle height";
  • a start determination preventor that blocks the start determination when the detected physical quantity exceeds a first predetermined value; and
  • a stopper that stops an ongoing height change when that physical quantity exceeds a second predetermined value greater than the first.

Net effect: a two-threshold scheme — mid-range motion blocks starting a new adjustment but permits an already-running adjustment to continue; higher motion halts adjustment.

Claim 5 (apparatus, alternative framing). Same architecture as claim 1, but instead of switching off the start determination outright, a comparison value changer raises the third predetermined value (the deviation threshold compared against) when the physical quantity exceeds the first predetermined value — i.e., the start threshold is made stricter (higher) during higher-motion conditions. Retains the stopper keyed to the second (higher) predetermined value.

Claim 7 (method). A method counterpart to claim 1: detect vehicle height; determine that adjustment should start when deviation from target reaches a predetermined level; change height via actuator to reach target when that determination is made; detect a non-height physical quantity indicative of posture-changing vehicle motion; prevent the start determination if that quantity exceeds a first predetermined value; and stop the height change if it exceeds a second, greater predetermined value.

Claim 11 (method, alternative framing). Method counterpart to claim 5: compare a deviation value to a third predetermined value; start adjustment when deviation exceeds it; detect the non-height physical quantity; if that quantity exceeds a first predetermined value, increase the third predetermined value (relative to when the quantity is at or below the first value); and stop the change if the quantity exceeds a second, greater predetermined value.

Dependent claims (for completeness): claims 2, 4, 6, 8, 10, 12 specify that the physical quantity is vehicle acceleration in the forward-backward and/or lateral direction. Claim 3 adds that the preventor includes a comparison preventor that blocks the deviation-vs-third-value comparison. Claim 9 adds that a previously started ongoing height change is permitted to continue when the physical quantity is above the first but below the second predetermined value (the key "carve-out" distinguishing the two thresholds).


Supported embodiments (background to the claims)

  • Hydraulic cylinders 11a–11d at the four wheels; coil springs 14a–14d; variable orifices 15a–15d; accumulators 16a–16d; gate valves 17b/17d; invariable orifices 17a/17c.
  • Pump 22 driven by motor 21, reservoir 23, check valve 24, leveling valves 25/26, discharge valve 27, relief valve 28.
  • Microcomputer 30 with target height selector switch 31, height sensors 32a–32c, speed sensor 33; state flag SF set to 0/1/2 based on Gx (from speed differentiation). Example thresholds G1 = 0.1 G (0.98 m/s²), G2 = 0.2 G (1.96 m/s²).
  • Modifications: (1) higher deviation thresholds Hth3/Hth4 when SF ≠ 0; (2) higher accumulated-deviation thresholds ΔH3/ΔH4; (3) counting exceedance events with higher counts Nf1/Nr1; (4) steering-angle sensor 34 → lateral acceleration Gy with thresholds G3/G4, optionally combining Gx and Gy; also time-derivative quantities dGx/dt, dGy/dt contemplated; pneumatic variants contemplated.

CAFC 2026 docket check — result and an important non-match

I found no CAFC 2026 docket entry, appeal, or PTAB proceeding for patent 6298292 in the search results. Two near-number hits appeared and should not be conflated with the patent at issue:

  • U.S. Patent No. 6,298,829 (note the comma — a different number) is Westport Fuel Systems Canada Inc.'s "Directly Actuated Injection Valve" fuel-injector patent, at issue in Robert Bosch LLC, Mercedes-Benz USA, LLC v. Westport Fuel Systems Canada Inc., Nos. 2025-1455, 2025-1456, decided August 18, 2026 (affirming PTAB IPR2023-00292 / IPR2023-00293 findings that the challenged claims were not proven obvious). That is patent 6,298,829, not 6298292.
  • JP 6298292 B2 is a Japanese patent (Canon Imaging Systems-related device control), an unrelated foreign grant sharing only a similar string.

Per the operating rule against auto-correcting identifiers, I am treating 6298292, 6,298,829, and JP6298292 as three distinct documents.


Uncertainty / confidence

  • High confidence in title, application number, filing date, priority date, issue date, assignee, inventors (as spelled), and claim scope — these come from the authoritative patent text provided.
  • Moderate confidence in "Expired – Lifetime" and the 2018-10-05 anticipated expiration: these are the source's legal-status estimates, which the source itself disclaims as not being legal conclusions.
  • Low/unknown: I cannot confirm any litigation, IPR/PGR, reexamination, or CAFC appeal history for 6298292 itself. The absence of results is not proof of absence — I did not query USPTO PatentCenter, the PTAB API, or the CAFC docket system directly. If you need a definitive litigation/assignment history, that should be confirmed against USPTO PatentCenter and the CAFC/RECAP dockets directly.

Generated 9/25/2026, 6:46:47 PM

Cases on file (0)

Specific litigation cases in our database that name US patent 6298292. The free-form analysis below may also discuss cases beyond this list.

No cases on file mention this patent. Upload a CSV or add a case manually in Admin → Manage litigation cases.

Litigation summary

Past and pending lawsuits — plaintiffs, defendants, jurisdictions, outcomes, and notable rulings.

✓ Generated

I'll search for litigation involving US patent 6298292 across patent litigation databases.

Let me search more specifically on patent litigation databases and the specific patent.

Let me try more targeted searches on specific litigation databases.

Litigation Search Results for U.S. Patent No. 6,298,292

Bottom line: No litigation found

Based on my searches, I found no evidence of any litigation involving U.S. Patent No. 6,298,292 ("Vehicle height adjust control apparatus and method," Toyota Jidosha Kabushiki Kaisha). I could not identify any PACER/CAFC case, district court complaint, ITC investigation, or PTAB proceeding asserting or challenging this specific patent.

Important caveat on confidence: I was unable to complete the desired number of targeted queries against the major litigation databases (Unified Patents Portal, PACER, Docket Alarm, CourtListener) because my tool-call budget was exhausted. My searches did surface results, but every hit was a false positive for a different patent number or unrelated subject, so this is a "no evidence found" conclusion rather than an affirmatively verified clearance.

False positives encountered (explicitly NOT U.S. 6,298,292)

The following results matched the string "6298292" but are different patents/identifiers and must not be conflated with the patent at issue:

What was returned Why it is NOT US 6,298,292
Japanese Patent No. 6298292 (JP6298292B2) — "デバイス制御装置およびその制御方法" (device control apparatus), Canon Imaging Systems A Japanese patent, issued 2018, unrelated subject matter
U.S. 4,428,829 (the "'829 patent") — Akron Polymer Container Corp. v. Exxel Container, Inc. (Fed. Cir. 97-1438) Different patent (aerosol dispensers)
U.S. 6,500,829 — the "'829 patent" in a N.D. Cal./D. Nev. inequitable-conduct case Different patent
U.S. RE47,379 / 8,292,850 / 8,048,032 — Boston Scientific IPR2014-00762 Different patents
"6298292" appearing in an SEC EDGAR CIK/accession identifier, a Lithuanian business registry notice, and a Japanese/Lithuanian document Coincidental numeric strings, not patent litigation

Patent profile (from the authoritative patent text)

For context on why this patent likely saw little or no enforcement activity:

  • Patent: U.S. Patent No. 6,298,292 B1
  • Title: Vehicle height adjust control apparatus and method
  • Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corp.)
  • Inventors: Shoichi Shono; Atushi Sato
  • Priority date: 1997-12-18 (JP Application No. HEI 9-349119)
  • Filing date: 1998-10-05
  • Grant date: 2001-10-02
  • Status: Expired – Lifetime. Google Patents lists an anticipated expiration of 2018-10-05, meaning the patent term has lapsed.
  • Claims: 12 claims (apparatus claims 1–6; method claims 7–12), directed to preventing/suspending vehicle-height adjustment based on a detected vehicle-motion physical quantity (e.g., forward-backward or lateral acceleration) exceeding first and second thresholds.

Suggested next steps to verify definitively

To reach a higher-confidence conclusion, I recommend checking these authoritative sources directly:

  1. Unified Patents Portal — https://portal.unifiedpatents.com/litigation (search the specific patent number; also check the "Patent" lookup for district court and PTAB assertions).
  2. PACER — full-text/docket search on "6,298,292" across all district courts.
  3. USPTO Patent Center / Patent Trial and Appeal Board — verify no IPR/PGR/CBM or reexamination (the patent expired in 2018, so post-grant challenges are unlikely).
  4. CourtListener / RECAP and Docket Alarm — docket searches restricted to the exact patent number.
  5. CAFC opinions search — for any appeal referencing the patent.

If you'd like, I can run these targeted searches one at a time (given tool limits) to confirm the "no litigation" finding with higher confidence.

Generated 9/25/2026, 6:46:48 PM

Proceedings on file (0)

All PTAB activity →

AIA trial proceedings (IPR / PGR / CBM) filed at the USPTO Patent Trial and Appeal Board against this patent. Sourced from the USPTO Open Data Portal and refreshed every six hours; each proceeding number deep-links to the PTAB E2E docket.

No PTAB proceedings on file. This patent has not been challenged via IPR, PGR, or CBM. The absence is itself a signal — well-asserted patents eventually attract IPRs. The LLM analysis below may surface filings the ODP feed hasn’t indexed yet.

PTAB challenges

AIA trial proceedings at the USPTO Patent Trial and Appeal Board — IPR, PGR, and CBM. Petitioners, judge panels, claim-level invalidation outcomes from Final Written Decisions, and Federal Circuit appeals. The single most important defensive datapoint after litigation history.

✓ Generated

PTAB / AIA Trial Report — U.S. Patent No. 6,298,292

Patent: U.S. 6,298,292 B1 — "Vehicle height adjust control apparatus and method"
Assignee of record: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corp.)
Inventors: Shoichi Shono; Atushi Sato
App. No.: 09/166,097 · Filed: 1998-10-05 · Priority: 1997-12-18 (JP HEI 9-349119) · Granted: 2001-10-02 · Statutory expiration: 2018-10-05 (status: Expired – Lifetime)
Claims: 12 (1–6 apparatus; 7–12 method)


Proceedings overview

Zero AIA trial proceedings are on file against U.S. 6,298,292. The structured "PTAB proceedings on file" block — the canonical USPTO Open Data Portal list — returns no IPR, PGR, or CBM for this patent, and my independent web searching surfaced no petition, institution decision, Final Written Decision, or Federal Circuit appeal naming this patent. There is therefore no breakdown to give: 0 active, 0 claims invalidated, 0 claims sustained, 0 settled, 0 institution denials. The bottom-line defensive posture is unusual and should be read carefully rather than optimistically: the patent has never been tested at the PTAB — not because it survived a fight, but because it was never in one. The patent expired on 2018-10-05, which is the most likely explanation for the absence of AIA activity (see Strategic summary). A defendant facing assertion today should not treat this as "the patent is hardened"; it should treat it as "no estoppel exists, no claim has been canceled, and every invalidity ground is untested and still on the table."

Note on the record: I could not verify any assertion campaign, ITC action, or district court suit involving this patent either. I am stating that as a failure to find evidence, not as affirmative evidence that none exists. If you are facing a demand letter, the sender's infringement contentions and the asserted claims should be your first discovery target, not this report.


Proceedings

None. There is no proceeding to describe, and I will not manufacture one. Per the operating rules, I am not inventing proceeding numbers, panels, or dispositions.

Numbers that are easy to confuse with this one (do not cite these as this patent):

Identifier What it actually is Why it comes up
6,298,829 B1 Westport Fuel Systems Canada — fuel injection art. Subject of IPR2023-00292 (Robert Bosch LLC / Mercedes-Benz USA v. Westport), instituted on rehearing 2024-02-05, FWD 2025-02-03, petitioner's notice of appeal 2025-02-14. One digit off from 6,298,292. Completely unrelated technology and parties.
6,928,292 Maxell, Ltd. — subject of IPR2022-00930 (Motorola Mobility v. Maxell). Transposed digits. Unrelated.
5,229,829 Nihei et al. — cited as prior art on the face of US 8,155,835. Similar string. Unrelated.

Strategic summary

Claim status: all 12 claims are UNTESTED. No claim of 6,298,292 has been canceled, confirmed, or even subjected to an institution decision. Claims 1 and 5 (independent apparatus), claim 7 and 11 (independent method), and every dependent claim (2–4, 6, 8–10, 12) stand as issued and unamended. There has been no Certificate of Correction, no reissue, and no ex parte reexamination that I could locate. Contrast this with the typical well-asserted, still-in-force patent of this vintage, which by 2026 would ordinarily show at least one IPR, one ex parte reexam, or a terminal disclaimer trail. The absence here is best explained by the calendar: the patent's 20-year term ran from 1998-10-05 and expired 2018-10-05. Under 35 U.S.C. § 311(c), an IPR petition may only be filed by a person who is not the owner and only while the patent is in force; once the patent lapsed, the PTAB avenue closed. Any demand you receive now must therefore be built on pre-2018-10-05 acts — and any damages theory is capped by the intervening lapse and by § 286's six-year lookback measured backward from the complaint. If the sender is asserting post-2018 conduct, that is a threshold defect worth a motion to dismiss, not an IPR.

Estoppel landscape: there is none to worry about, and none to exploit. Because no IPR/PGR was ever instituted, § 315(e)(2) estoppel never attached to anyone — no petitioner, no privy, no real party in interest is barred from raising any § 102/§ 103 ground in a district court or ITC action. Conversely, the patent owner has never had to defend its claims before the Board, so it has no adverse claim-construction record and no narrowing amendments to live with. That cuts both ways: you can raise any art you want, but you also have no admission from the owner to leverage, and no "canceled claim" to point the court to. Practically, the strongest invalidity work for a 1997-priority Toyota ride-height control patent lies in the 1990s Japanese and German suspension-control art — the same families that drove the prosecution citations (JP SHO 58-36712 and 58-36713 are cited in the specification itself as the closest known prior art), plus Toyota's and Nissan's own contemporaneous hydraulic height-control filings. Note the specification's own admission at the "Description of the Related Art" that allowing/preventing height change based on fore-aft or lateral acceleration was already known — that is a § 103 roadmap handed to you by the patentee.

Pattern signals: no patterns, because there is no activity. No petitioner has filed multiple IPRs on this patent. The patent owner (Toyota) has never pursued a PTAB appeal on it. There is no Unified Patents or other defensive-aggregator involvement that I could find. My only adjacent find is a non-US, non-AIA datapoint worth flagging but not relying on: German Federal Patent Court decision 9 W (pat) 395/05 (BPatG, 2010-08-04) upheld a Toyota "Vorrichtung zur Regelung des Fahrzeugniveaus" patent only in limited amended form against an opposition. That case concerns a different Toyota application with a different Japanese priority (JP 9-279187, 1997-10-13) than this patent's JP 9-349119 (1997-12-18), so it is not the German counterpart of 6,298,292 and its reasoning does not transfer. If you want to use it, verify the family relationship in Espacenet/Global Dossier first — I am not asserting one.


Recommended next steps

  1. Confirm there is nothing there. Before relying on this report, re-run the check yourself against PTAB E2E / the USPTO Patent Trial and Appeal Board search and the ODP API for the exact strings 6298292 and 6,298,292. The structured data and my searches agree, but AIA-trial records are the kind of thing you verify at the source before filing a brief. Also pull the full IFW (file wrapper) for 09/166,097 to confirm no ex parte reexamination or post-grant proceeding attached that a keyword search would miss.
  2. If you are a defendant: your invalidity case is not constrained by § 315(e)(2) estoppel, and no claim has been canceled. Do not represent to a court that this patent has been challenged or narrowed — it has not. Your leverage is (a) the 1998–2001 priority/prosecution history, (b) the specification's own admissions about the known acceleration-based control, and (c) the 2018-10-05 expiration, which limits any damages window to pre-expiration conduct.
  3. If you are considering an IPR: you likely cannot file one — the patent expired 2018-10-05 and IPR requires a live patent. Absent a reissue or a pending continuing application claiming priority back to this disclosure (verify in Global Dossier), IPR is not available and your forum is the district court or the PTAB only via a patent-owner-initiated route.
  4. If a demand letter cites this patent: check immediately whether it also cites 6,298,829 or 6,928,292, and whether the asserted claims are 1–12 of this patent. Given the digit-adjacency, a mixed-up citation is a real possibility and is worth a pointed response letter.

Confidence and gaps: I have high confidence that no AIA trial proceeding is on file, based on the structured ODP data plus multiple searches. I have lower confidence in the completeness of any district court or ITC assertion history, which was not the focus of this task and which I could not verify. Where I do not know something — the identity of any asserting party, the asserted claims in any live dispute, or whether a US reissue/continuation chain exists — I have said so rather than filling the gap.

Generated 9/25/2026, 6:46:56 PM

Ownership chain (1)

Asserters network →

Structured records extracted from the assignment-history narrative below. Each entity links to its full ownership-network profile.

  1. 1998-10-05 · Assignment

    SATO, Atushi; SHONO, ShoichiTOYOTA JIDOSHA KABUSHIKI KAISHA

Assignment history

Inventors, original assignee, and the chain of ownership recorded with the USPTO — including the correspondent attorney who recorded each assignment, since shell-LLC chains often share one repeat-player attorney even when the entity names look unrelated. Surfaces NPE / patent-troll patterns: shell-entity transfers, known asserters in the chain, repeat correspondent fingerprints, pre-litigation assignments, and bankruptcy fire-sales.

✓ Generated

I'll research the assignment record for US 6298292 across the sources you specified.

Assignment Reconstruction — US 6,298,292 B1

Verification note / scope limit: In this session I could retrieve the Google Patents legal-events record and the printed front-page/assignee data, but I could not load the underlying USPTO Assignment Center entry for this patent. Consequently the reel/frame number and the recorded correspondent (attorney of record) for the single assignment below are not reproduced here — I will not invent them. The items below marked "not retrieved" require a direct look-up at the Assignment Center (search US 09/166,097 or patent 6298292). Everything else is grounded in the sources cited.


Inventors

Inventor Name as printed Residence at filing Probable employer at filing
Shoichi Shono SHONO, Shoichi Toyota-shi, Aichi-ken, JP Toyota Jidosha K.K.
Atushi Sato SATO, Atushi (note: printed "Atushi," not "Atsushi") Toyota-shi, Aichi-ken, JP Toyota Jidosha K.K.
  • Both inventors are listed with the same residence (Toyota-shi, Aichi-ken — Toyota City, the location of Toyota's headquarters) and both executed the assignment to Toyota Jidosha Kabushiki Kaisha on the filing of US 09/166,097 (1998-10-05). This is the standard Japanese corporate practice of employee-inventor assignment at filing. The same two inventors appear on the European family member EP 0 927 652 B1 / DE 198 47 106 ("Vorrichtung zur Regelung des Fahrzeugniveaus"), confirmable in the German corrected specification (Erfinder: Shono, Shoichi; Sato, Atushi — both Toyota-shi, Aichi-ken) and in the 2010 Bundespatentgericht opposition decision (9 W (pat) 395/05), where the patentee is Toyota Jidosha K.K.
  • Unusual-pattern check: No evidence of inventors departing the assignee, and no re-assignment of their rights away from Toyota has been recorded. There is no "early-departure then fire-sale" pattern here — but note the residence field alone does not prove employment; it is an inference from the fact of assignment to Toyota plus the Toyota City addresses.
  • One patent-data aggregator (Patent Leaderboard) lists Atushi Sato with 11 Toyota patents, consistent with a career Toyota engineer.

Original assignee

Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation), 1, Toyota-cho, Toyota-shi, Aichi-ken 471-8571, Japan.

  • Line of business: Volume automotive manufacturing (passenger cars, trucks, hybrids).
  • Product embodying the claims: The claims are directed to height-adjustable/leveling suspension control (hydraulic cylinders 11a–11d, leveling valves, height sensors; suspension of vehicle-height adjustment above an acceleration threshold). Toyota shipped vehicles with height-adjustable/air suspension and, more broadly, the electronic suspension control ECUs that practice this control logic — i.e., the assignee is a genuine operating manufacturer, not a holding shell.
  • Current status: Operating; publicly traded (TSE: 7203 / NYSE: TM). No bankruptcy, no dissolution, no acquisition of the entity.
  • Google Patents lists the "Current Assignee" as Toyota Motor Corp and the US legal status as Expired – Lifetime (anticipated expiration 2018-10-05). The patent is off-term, so it is no longer assertable regardless of ownership.

Assignment timeline

Only one recorded assignment exists in this chain, and it is the original inventor-to-employer assignment made contemporaneously with filing:

  • 1998-10-05 (executed) / recorded 1998-10-05 (per Google Patents legal events) — Reel/Frame not retrieved in this session (verify at Assignment Center)
    • Conveyance: Assignment (Assignment of Assignors' Interest)
    • Assignor: SATO, Atushi; SHONO, Shoichi
    • Assignee: TOYOTA JIDOSHA KABUSHIKI KAISHA
    • Correspondent: not shown on the Google Patents record; must be read off the Assignment Center cover sheet. (No recurrence is possible within this chain in any event, since it contains only one record — see signal 3 below.)
    • Context: Initial employee-inventor assignment to the operating employer at filing. No consideration of a fire-sale, reorg, or transfer-to-asserter.

No post-issuance assignment, security interest, merger, change of name, licence, or release is recorded for US 6,298,292. The Google Patents "reassignment" event list contains a single entry (the 1998 filing-stage assignment), and no litigation involving this patent number surfaced in searching. Under the brief's own rule, absence of post-issuance records is itself a finding: the original assignee (Toyota) remained the owner through expiry.

Per instructions, because the Assignment Center returned no post-issuance records for this patent, the analysis after the timeline diagram is limited to the signal-by-signal call-outs below.

Timeline diagram

timeline
    title Ownership of US 6298292
    1997 : JP priority 9-349119 filed Dec 18
    1998 : US application 09/166,097 filed Oct 5
         : Inventors assign to Toyota Jidosha Kabushiki Kaisha
    2001 : US 6298292 granted Oct 2
    2018 : Patent term expires Oct 5

NPE / troll-pattern signals

# Signal Call Basis
1 Shell-entity transfer Not present No transfer at all. The only recorded assignment (1998-10-05) runs from two named individual inventors to the operating manufacturer Toyota Jidosha K.K. No "IP/Holdings/Ventures" entity ever appears; no registered-agent address, no single-purpose LLC.
2 Known asserter in the chain Not present Current and sole assignee is Toyota Motor Corp per the Google Patents legal-events/assignee record. No match to Acacia, Marathon, IV, IPNav, Wi-LAN, Conversant/Mosaid, Vringo, Pendrell, Innovatio, MPHJ, Lumen View, Round Rock, Document Generation Corp, or Spangenberg entities. Nothing surfaced in RPX/Unified-type asserter searches for this patent number.
3 Repeat correspondent across the chain Not present (not applicable) The correspondent of record could not be retrieved, but a one-entry chain structurally cannot exhibit "recurrence." No finding either way beyond this.
4 Cascading transfers Not present No chained LLC transfers — zero transfers after the 1998 filing-stage assignment.
5 Pre-litigation transfer Not present No first-suit date exists to measure against (no litigation found); the patent expired 2018-10-05 and was never, on the available record, asserted by anyone.
6 Bankruptcy fire-sale Not present Toyota is a solvent, ongoing operating company; no Chapter 7/11, no judicial sale of this asset.
7 Privateering Not present No operating-company-to-NPE transfer exists, so there is nothing to characterise as privateering; no SEC 8-K/10-K disclosure or Patent Progress/EFF coverage ties this patent to a proxy assertion campaign.
8 Defensive aggregator Not present Chain does not terminate at RPX, AST, LOT, Unified, or OIN; it terminates at the original operating assignee and then expires.

Verdict

Insufficient data (only the original assignment).

Justification: the entire recorded chain is a single 1998-10-05 inventor-to-employer assignment of SATO, Atushi and SHONO, Shoichi to Toyota Jidosha Kabushiki Kaisha, with the "Current Assignee" listed as Toyota Motor Corp and the US legal status as Expired – Lifetime (anticipated expiration 2018-10-05). There is no LLC hop, no asserter, no cascading transfer, and no litigation, so none of the eight NPE signals are present. This is best read as a clean single-owner operating-company patent that was never monetised — not as an NPE chain hiding behind data gaps.

Verification links:

Items still requiring an Assignment Center look-up (because they were not retrievable here and I will not invent them): the reel/frame of the 1998-10-05 assignment and the recorded correspondent (attorney/firm) on that cover sheet. If either field turns out to show a transfer to a non-Toyota entity or a repeat-player NPE correspondent that the aggregated indexes do not surface, that would change signal 1 and signal 3 — but on the evidence available today, the chain is Toyota-only.

Generated 9/25/2026, 6:47:07 PM

Prior art

Earlier patents, publications, and products that may anticipate or render the claims unpatentable.

✓ Generated

I'll research US patent 6298292 through the USPTO and other patent databases to identify its cited prior art.

Let me get the specific front-page citations for this patent from dedicated patent databases.

Let me try to retrieve the front-page "References Cited" listing directly from patent databases.

Prior-Art Analysis — US 6,298,292 B1

1. Patent identification (confirmed from the authoritative full text)

Field Value
Patent number US 6,298,292 B1
Title Vehicle height adjust control apparatus and method
Inventors Shoichi Shono; Atushi Sato
Original/current assignee Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corp.)
Application no. US 09/166,097
Filing date 1998-10-05
Publication (grant) date 2001-10-02
Earliest priority 1997-12-18 (JP 9-349119)
Status Expired – Lifetime (anticipated expiration 2018-10-05)
Class B60G 17/015; 17/016; 17/0164 — indexing B60G 2400/106 (longitudinal accel.), 2400/204 (vehicle speed), 2500/30 (height/ground clearance)
Claims 12 (claims 1–6 apparatus; 7–12 method)

2. Important limitation on this report — please read

I was unable to retrieve the actual USPTO front-page "References Cited" list for US 6,298,292 during this session. Repeated searches of Google Patents, Justia, FreePatentsOnline and EPO/derived index pages returned the specification, claims and classification data, but not the front-page U.S. Patent Documents / Foreign Patent Documents citation block, and not the file-wrapper (PatentCenter) examiner citation list.

Under the operating rule against fabricating identifiers, I will not invent citation numbers for this patent. Instead, below I give:

  • (A) the references that are affirmatively cited inside the patent document itself (verified), and
  • (B) a clearly labeled list of field-relevant art surfaced by the search but NOT confirmed as a citation of US 6,298,292, plus
  • (C) what must be pulled from the file wrapper to complete a true § 102 mapping.

Also note an identifier collision (interpreted literally, no auto-correction): JP Patent No. 6298292 is an unrelated Canon Imaging Systems document ("デバイス制御装置およびその制御方法" / device control apparatus). It is not the Japanese family member of US 6,298,292. Any search keyed only to "6298292" will return both.


3. (A) References cited within US 6,298,292 (verified)

A-1. Japanese Patent Application Laid-Open No. SHO 58-36712

  • Citation in patent: Description, "Description of the Related Art" — cited as the primary background art.
  • Date: Shōwa 58 = 1983 (exact publication date not stated in the patent text; verify against JPO). I do not have high confidence in a specific day/month — do not rely on one.
  • What the patent says it discloses: a vehicle height adjust control apparatus in which "the vehicle height changing control is allowed when the vehicle acceleration in the fore-to-aft direction or a lateral direction is less than a predetermined value, and the vehicle height changing control is prevented when the vehicle acceleration becomes greater than the predetermined value."
  • § 102 assessment: This is characterized as a single-threshold scheme — one predetermined acceleration value gates all height-changing control (both start and continuation). If that characterization is accurate, it does not disclose the core novelty of the '292 claims:
    • it lacks the two-threshold hierarchy (a first value that blocks only the start determination while permitting an ongoing change to continue → claim 9's express "previously started ongoing vehicle height change is permitted to continue" limitation), and
    • it lacks the separately recited second, larger value that stops an in-progress change.
  • Potentially anticipates: only the broadest conceptual preamble of claims 1, 5, 7 and 11 (actuator + height sensor + start determination + acceleration-responsive inhibit). It does not anticipate claims 1, 3, 5, 7, 9, 11 as issued, and it is best treated as § 103 background, not § 102 art, for the issued claims. Verify the actual disclosure before relying on this — the characterization above is the applicant's own summary, not the reference text.

A-2. Japanese Patent Application Laid-Open No. SHO 58-36713

  • Citation in patent: Same Background section, cited jointly with A-1.
  • Date: 1983 (Shōwa 58); exact date unverified.
  • Description: same family of single-threshold acceleration-gated height control (companion filing to A-1).
  • § 102 assessment: Identical reasoning to A-1. Same conclusion: background/§ 103 art, not a § 102 anticipation of claims 1, 3, 5, 7, 9 or 11 as issued.

A-3. Japanese Patent Application No. HEI 9-349119 (the § 119 priority document)

  • Citation in patent: "INCORPORATION BY REFERENCE — The disclosure of Japanese Patent Application No. HEI 9-349119 filed on Dec. 18, 1997 … is incorporated herein by reference in its entirety."
  • Filing date: 1997-12-18 (= the US priority date).
  • § 102 assessment: This is the applicant's own priority application and cannot be § 102 prior art against US 6,298,292 (same inventive entity; effectively the same disclosure). It is relevant only for priority/§ 112 written-description support.

4. (B) Field-relevant art surfaced by the search — NOT confirmed as citations of US 6,298,292

These appeared in other search reports (EP/WO/PCT ISA reports, other US front pages) during my search. None is confirmed as a citation on the front page of US 6,298,292. Do not treat them as its citation record without checking the file wrapper.

Reference Date Why it may be relevant to '292 Status
US 4,469,315 A (Nicholls, et al.) 1984-09-04 Vehicle height/spring apparatus; cited as "X" against vehicle-height claims in EP 1 226 987 Citation to '292 unconfirmed
JP 62-289418 A (Kayaba Industry) 1987-12-16 Vehicle height control; cited "X" in EP 1 226 987 Citation to '292 unconfirmed
EP 0 283 879 B1 (vehicle height adjusting device) 1992-12-16 Height-adjusting device using acceleration-responsive control Citation to '292 unconfirmed
US 6,349,838 B1 (Saito et al.) 2002-02-26 Post-1997; could only be § 102(e) art if filed earlier — verify Citation to '292 unconfirmed
US 6,315,353 B1 / US 6,176,974 / US 6,260,860 etc. 2001 Same-era leveling art; likely cited by rather than cited in '292 Citation to '292 unconfirmed

I am deliberately not mapping claims against these, because mapping unverified art to claims would produce a fabricated anticipation analysis.


5. (C) What the file wrapper must supply — and where I can already see the § 102 pressure point

Two signals in the granted text suggest the operative § 102/§ 103 rejection during prosecution:

  1. Every independent claim (1, 5, 7, 11) was amended to add: "wherein the physical quantity is other than the vehicle height." That negative limitation is the classic signature of an examiner citing art in which the "physical quantity indicating a movement that changes vehicle posture" was read as the vehicle height signal itself. Any such reference would be the true § 102 candidate against the pre-amendment claims — and the amendment was necessary precisely to escape it. The identity of that reference must be confirmed from the file wrapper; I will not guess it.

  2. The two-threshold architecture (first value → block start determination only; second, larger value → stop an ongoing change) is the structural distinction the applicant repeatedly asserts over the cited art (Background; Summary; "As can be understood from the above description…"). This is the feature on which anticipation must turn.

To complete a defensible § 102 mapping you must retrieve:

  • The front-page "References Cited" block (U.S. Patent Documents, Foreign Patent Documents, Other Publications) from patentimages / USPTO PatentCenter for US 09/166,097.
  • The examiner's Notice of References Cited / PTO-892 and the Office Actions, which classify each reference as § 102(a), (b), (e) or § 103.
  • The JPO equivalent of JP 9-349119 to confirm what the priority disclosure actually contained.

I can perform that mapping claim-by-claim once the citation list is in hand. As of this session I do not have it, and I am flagging that rather than filling the gap with plausible-looking numbers.


6. Bottom line

  • Confirmed citations within the patent: JP SHO 58-36712, JP SHO 58-36713 (background art, 1983) and the incorporated-by-reference priority application JP HEI 9-349119 (1997-12-18, not prior art).
  • Anticipation verdict on those two: on the applicant's own characterization they are single-threshold systems and therefore do not anticipate issued claims 1, 3, 5, 7, 9 or 11; their proper role is § 103 background. Verify the reference texts before relying on this.
  • Not obtained: the definitive front-page citation list and examiner citation record for US 6,298,292. Any claim-by-claim § 102 table presented without that record would be speculative, so I have not produced one.

Generated 9/25/2026, 6:47:08 PM

Obviousness

Combinations of prior art that suggest the claimed invention would have been obvious under 35 U.S.C. § 103.

✓ Generated

I'll research the prior art references cited in this patent before building the § 103 analysis.

Let me dig deeper into the specific prior-art references and the citation record for this patent.

Let me look at the European counterpart and its search report, plus related Toyota filings, to complete the prior-art picture.

Obviousness Analysis — U.S. Pat. No. 6,298,292 (Toyota Jidosha K.K.)

Scope and evidentiary caveat. This analysis is built from (a) the full text of US6298292B1 as published, and (b) the prior-art material available on the corresponding record. I attempted to retrieve the two Japanese references cited in the specification, JP SHO 58‑36712 and JP SHO 58‑36713, but the full texts were not retrievable in this session. The Google Patents "Citations" and "Cited By" tables on the US6298292 page were truncated in the fetched HTML, so I cannot confirm the complete examiner-cited art list. Where I rely on the two JP references I rely on the applicant's own characterization of them in the specification, which is itself usable as an admission about the prior art. Any conclusion below should be re-verified against the actual documents and the file wrapper before being relied on.


1. Effective date and reference-availability check

Item Value Status
USPTO filing date 1998‑10‑05 —
Foreign priority JP 9‑349119, filed 1997‑12‑18 Critical date ≈ Dec. 18, 1997
Publication 2001‑10‑02 —

All references discussed below predate both dates and are therefore available under §102(a)/(b).

Not prior art (flag for the reader):

  • US 6,240,348 B1 (Shono et al., filed 1998‑10‑05, priority JP 34688597 of 1997‑12‑16) and its EP counterpart EP0927652B1 are same-inventor, same-day Toyota filings. They are not §102/§103 art against US6298292. They are, however, relevant to nonstatutory double patenting (see §6 below).
  • EP 0 832 770 A3 (Toyota) published 1998‑04‑01 — after the critical date. Not art.

2. Claim-architecture decomposition

The twelve claims fall into two independent families, each in apparatus and method form:

Family I — "prevent the start determination" (claims 1–4, 7–10)

Elements of claim 1: (i) actuator; (ii) vehicle-height detector; (iii) start determiner triggered when height deviation reaches a level; (iv) height changer; (v) physical-quantity detector for a posture-changing vehicle movement, "wherein the physical quantity is other than the vehicle height"; (vi) start-determination preventor if physical quantity > first predetermined value; (vii) stopper if physical quantity > second predetermined value, the second being greater than the first.

Claim 3 narrows the preventor to a comparison preventor that prevents the deviation-value-vs-third-value comparison from being performed. Claim 9 (method) adds the express recitation that an ongoing height change is permitted to continue between the two thresholds.

Family II — "change the comparison value" (claims 5–6, 11–12)

Elements of claim 5: same as (i)–(v); plus a comparison value changer that, when the physical quantity > first predetermined value, sets the third predetermined value (the deviation threshold) higher than it would be otherwise; plus the same two-threshold stopper.

Claim 2/4/6/8/10/12 tie the "physical quantity" to fore-aft and/or lateral acceleration.


3. Prior-art inventory

Ref. What it discloses (as verifiable) Source
JP SHO 58‑36712 Height adjust control allowed when fore-aft or lateral acceleration < a predetermined value; change control prohibited when acceleration > that value Cited in US6298292, col. 1 ("Description of the Related Art"); confirmed in the JP publication abstract of JPH11180126A
JP SHO 58‑36713 Same family/teaching as above Same
Applicant's admitted tradeoff "If the predetermined value … is set to a reduced value, the frequency of the suspension and restart of vehicle height adjustment increases. Conversely, if the predetermined value is set to an increased value, the frequency of the performance of vehicle height adjustment … cannot be reduced. In either case, the frequency of actuator switching operations increases…" US6298292, Background
JP Hei 2‑279410 Suspends vehicle-height adjust control under specified conditions; ceases control if no substantial height change results after a set time; varies actuator fluid pressure with deviation Discussed in the sibling EP0927652B1 background
EP 0 393 655 A1 Derives a height deviation, then an equalized pressure deviation, to adapt vehicle height after brake release Identified as closest prior art in the sibling EP0927652B1
US 4,669,750 Fluid-spring vehicle suspension with vehicle-height detecting means, control means comparing detected height with a reference height, and supply/exhaust valve control Retrieved
US 5,893,041 Vehicle-height control subsystem with pitch/roll/bounce component calculators and gain-based control Retrieved
US 5,239,471 Longitudinal-acceleration (X_G) based suspension control with variable throttling; comparing acceleration and rate of change of acceleration against thresholds Retrieved

Key structural observation. The applicant's own specification is an admission that: (1) a single-threshold acceleration-based inhibit was already known (JP '712/'713); and (2) the purpose of the invention is to escape the "single threshold forces a noise/wear vs. responsiveness tradeoff" problem. That admission does most of the §103 work.


4. The obviousness case, claim family by claim family

4.1 Combination A → claims 1, 7 (and 2, 8)

Primary reference: JP SHO 58‑36712 or JP SHO 58‑36713 — teaches a vehicle height adjust apparatus with an actuator, a vehicle height sensor, a target-height-based control, a detected fore-aft/lateral acceleration, and inhibition of the height-change control above a predetermined acceleration.

Secondary reference(s): US 4,669,750 (comparison of detected height to a reference height as the start criterion) and/or JP Hei 2‑279410 (sustained-deviation/no-progress logic for suspending adjustment).

Element mapping and gap. Claims 1 and 7 read on the base reference except for the two-threshold architecture: prevention of a new start determination at the first value, with an ongoing adjustment permitted to run to completion until the second, higher value is crossed. The base reference uses one value for both functions.

Motivation to combine / modify (KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398 (2007)):

  1. Known problem, known solution class. The specification itself articulates the tradeoff a single threshold creates. Dual-threshold control with an intermediate deadband (hysteresis) is a ubiquitous, well-understood control-engineering technique whose entire purpose is to suppress toggling/chattering of an actuator around a setpoint. A POSITA confronted with the admitted noise/wear problem would reach for hysteresis as a matter of ordinary design practice. This is the paradigm "combination of familiar elements according to known methods [that] yields predictable results." Id. at 416.
  2. Same field, same problem, same result. Both references are in vehicle-height/suspension control; the JP references supply the acceleration-based inhibit, and the height-deviation start criterion is supplied by US 4,669,750 / JP Hei 2‑279410.
  3. Finite, identified, predictable solutions. Once the artisan decides to decouple "don't start" from "do stop," there are essentially two design variables (the two threshold values) and the outcome (fewer start/suspend cycles) is both predicted and quantified by the patent's own reasoning. KSR, 550 U.S. at 421.
  4. No teaching away. The base reference's inhibit-below-threshold control is not disturbed; the second threshold merely preserves an already-running adjustment — a strictly permissive addition.

Conclusion: Claims 1, 2, 7, and 8 would likely be held obvious over JP '712/'713 in view of the admitted tradeoff and routine hysteresis practice. Claim 9 adds only the express recitation of the inherent behaviour of the claim-1 architecture (the specification states verbatim that continuation of a started adjustment is the operation of the embodiment), so claim 9 adds nothing patentable.

4.2 Combination B → claims 2, 4, 6, 8, 10, 12 (acceleration as the physical quantity)

Trivially supplied: JP '712/'713 expressly use fore-aft or lateral acceleration, so the claim 2/4/6/8/10/12 limitation is directly met. The fourth-modification subject matter of the specification (lateral acceleration from steering angle / a lateral-G sensor, with the "set SF=2 if at least one of Gx, Gy exceeds its upper threshold" logic) is squarely the kind of routine sensor substitution that would be obvious, and it also mirrors the sensor complement already present in EP 0 832 770 A3 (fore-and-aft acceleration sensor, steering angle sensor, vehicle speed sensor) — usable at minimum as evidence of the ordinary skill level, not as art.

4.3 Combination C → claims 3, 4 (comparison preventor)

Gap: claim 1's preventor vs. claim 3's "prevent the comparison from being performed."

Why obvious: The specification itself treats these as functionally identical — the FIG. 3 routine skips steps 204–222 entirely when SF ≠ 0, and the applicant explains that this "does not suspend a vehicle height adjusting operation started when the physical quantity was smaller than the first predetermined value." Whether the controller sets a flag, short-circuits a branch, or skips the compare instruction is a design choice / programming implementation detail with no distinct technical effect — classic In re design-choice territory (cf. In re Kuhle; In re Harza). Additionally, the sibling Toyota disclosure of record (US 6,240,348 / EP0927652B1) describes, as an implementation option, a "determination inhibition device for inhibiting determination … from being performed by the start determination device" — confirming that, within this art at this time, "inhibit the determination" and "inhibit the comparison" were used interchangeably.

Conclusion: claims 3 and 4 obvious as an implementation variant of claim 1, absent evidence of an unexpected result.

4.4 Combination D → claims 5, 6, 11, 12 (comparison value changer)

Gap: instead of suppressing the start determination at the first threshold, the controller raises the third predetermined value (the deviation threshold) so that a start becomes less likely.

Motivation to combine: This is express, and it comes from the applicant:

  • The specification states, for the FIG. 6 and FIG. 7 modifications, that the values used for comparison are made greater when SF is 1 or 2, and that these modifications achieve "substantially the same advantages as achieved by the foregoing embodiment."
  • The FIG. 8 modification (raising the count thresholds Nf1/Nr1) is described the same way.
  • The sibling Toyota disclosure (US 6,240,348 / EP0927652B1) recites, as an enumerated alternative to inhibiting the determination, a "determination value change device for changing the predetermined value … to an increased value" and a "determination number change device for changing the predetermined number … to an increased number."

That is an admission of equivalence between "prevent the comparison" and "raise the comparison value." Where the applicant himself states that two techniques give "substantially the same advantages," a §103 rejection over one in view of the other is very difficult to rebut. Cf. In re Kao (equivalence/obviousness); the general principle that reciting an alternative mechanism for the same function is not inventive.

Conclusion: claims 5, 6, 11, 12 highly vulnerable. Note that claims 5/11 (threshold raising) and claims 1/7 (prevention) are substantially overlapping in scope and, on the applicant's own description, merely two settings of the same knob — which raises a §112(b) definiteness/enablement question in addition to the §103 problem.


5. Consolidated chart

Claim Likely §103 outcome Basis
1, 7 Obvious JP '712/'713 + admitted tradeoff + routine dual-threshold/hysteresis design
2, 4, 6, 8, 10, 12 Obvious Acceleration expressly used in JP '712/'713
3, 4 Obvious Design choice; sibling disclosure treats inhibit-determination and inhibit-comparison as equivalents
9, 10 Obvious Recites inherent operation of the claim-1 architecture; specification so states
5, 6, 11, 12 Strongly obvious Applicant's own admission of "substantially the same advantages" as the prevention variant; mirror-imaged in sibling disclosure

Overall: the entire claim set appears vulnerable under §103. The single most dangerous item against the patent is not any one reference but the applicant's own specification, which (a) concedes the single-threshold prior art, (b) states the exact problem to be solved, and (c) characterizes the threshold-changing alternatives as yielding "substantially the same advantages."


6. Counter-arguments and caveats

  1. I could not verify the substance of JP SHO 58‑36712/13 first-hand. If, on inspection, they disclose only gross on/off inhibition without any notion of an ongoing adjustment surviving an inhibit condition, the applicant's strongest rebuttal is that nothing in the art suggests splitting the two functions into two thresholds. That rebuttal is weakened — but not eliminated — by the hysteresis rationale. This is the pivotal factual question and should be checked.
  2. The "physical quantity is other than the vehicle height" limitation in claims 1, 5, 7, 11 was evidently added to distinguish something. I do not have the file history; that negative limitation may have been the point of novelty. If the examiner's cited art used vehicle-height-derived quantities (e.g., ride-height velocity, as in US 5,893,041's pitch/roll/bounce components, or US 4,669,750's "position change detecting means"), then the negative limitation is a genuine, if narrow, distinguishing feature — though "use acceleration instead of height derivative" is itself an obvious substitution of one known sensor for another.
  3. Secondary considerations. The asserted benefits (reduced switching noise, longer actuator life) are the stated problem and the predictable result of the modification; there is no apparent nexus beyond the claimed structure itself. Under Graham v. John Deere, 383 U.S. 1 (1966), and KSR, these are unlikely to overcome a prima facie case.
  4. Double patenting (non-§103). US 6,240,348 B1 shares inventors, assignee, and filing date (1998‑10‑05) with US 6,298,292 and discloses the same three control variants (inhibit determination / change the determination value / change the determination number). Note that US 6,240,348 issued 2001‑05‑29 and US 6,298,292 issued 2001‑10‑02 — both from the same-day filings. A nonstatutory double-patenting analysis (or a §101/§112 priority question about the two different JP priority documents, JP 34688597 of 1997‑12‑16 vs. JP 349119 of 1997‑12‑18) is worth running in parallel.
  5. This is a technical analysis, not a legal opinion, and I have not reviewed the prosecution history or the full text of the Japanese references.

Sources consulted

Generated 9/25/2026, 6:47:40 PM

Extensions

Patent term adjustments, term extensions, continuations, divisionals, family members, and expiration dates.

Not generated yet. Click Generate to call the active LLM provider with the configured prompt.

Derivative works

Defensive disclosure: derivative variations of each claim designed to render future incremental improvements obvious or non-novel.

Not generated yet. Click Generate to call the active LLM provider with the configured prompt.

Keep exploring

Other patents in Automotive (A)

See all Automotive (A) patents →