US 6591808

I'll verify this patent against the USPTO record and check for any 2026 CAFC activity before summarizing.

Verification note

I searched for US 6591808 specifically (patent number, title, and US 6,591,808 formats). The authoritative full text you supplied (Google Patents, fetched 2026‑09‑23) and the search results agree on all bibliographic fields. I found no Federal Circuit or other 2026 docket activity, and no IPR/PGR, naming this patent — the only Federal Circuit 2026 Ford-related items in my results were Versata Software v. Ford Motor Co. (24‑1140 et al.) and Insulet v. EOFlow, neither of which involves US 6591808. Treat the "no litigation found" statement as a limitation of my search, not proof of absence.

US 6,591,808 B2 — Bibliographic summary

Assignment-record note (flagged as an observation only): the recorded assignment of 2002‑02‑22 from the inventors to Ford Motor Company lists assignors Zaremba, Badreddine, and Sun (signed 2001‑04‑03 to 2001‑04‑05). Feng Lin is listed as an inventor in the front-page data but does not appear in that recorded inventor-assignment entry. I cannot resolve from the material available whether this is a records artifact or a substantive omission.

Abstract (verbatim)

"Within both a method for operating an internal combustion engine and a system for operating the internal combustion engine there is provided an engine rotation speed pulsation damping within the internal combustion engine through use of a PID controller which varies a single PID control parameter, particularly, K_D to provide the engine rotation speed pulsation damping within the internal combustion engine. Within both the method and the system there is also provided a pair of control algorithms for use within the PID controller such as to effect the desired engine rotation speed pulsation damping when operating the internal combustion engine."

Plain-language overview of the independent claims

Claim 1 — Method (independent). Put an engine speed sensor and a supplemental torque source (described in the spec as a starter motor or starter/alternator induction machine driven off the crankshaft) on an engine, with the torque source governed by a PID controller. While the engine is running, continuously determine three input values — desired engine speed, observed engine speed, and the supplemental torque being delivered by the torque source — and feed them to the PID controller. Then, via a control algorithm inside the PID controller operating on those inputs, continuously adjust one single PID control parameter to command the supplemental torque source so that engine speed pulsation is damped. (Claim 2 adds that the single parameter is K_D; claims 3 and 5 recite the two alternative algorithm equations; claims 4 and 6 recite numeric ranges; claim 7 adds the vehicle context.)

Claim 8 — System (independent). The apparatus counterpart: an engine with a speed sensor and a supplemental torque source, plus a PID controller that controls the torque source. The PID controller has as its inputs at least desired engine speed, observed engine speed, and supplemental torque, and is programmed with a control algorithm that operates on those inputs to vary a single PID control parameter for control of the supplemental torque source, so as to damp engine speed pulsation during engine operation. (Claims 9–14 mirror the method dependents: K_D as the single parameter, the two algorithm equations, the coefficient ranges, and the vehicle context.)

The substantive point of both independents is narrow: damp idle/rotation-speed pulsation by adaptively tuning only one PID gain (in practice the derivative gain K_D), using an adaptation law derived from adaptive-interaction theory rather than by tuning K_P, K_I, and K_D jointly.

Algorithm equations as literally claimed (reproduced without correction; note the internal inconsistencies described below):

• Claim 3 (and claim 10): dk/dt_i(i=P,I,D) = 2γ₁ ( e ( g(t) * y_i(i=1,2,3) ) − α₁ u y_i(i=1,2,3) )
• Claim 5 (and claim 12): dk/dt_i(i=P,I,D) = 2γ₂ ( e y_i(i=1,2,3) − k₂ u y_i(i=1,2,3) ) — but the "where" clause and dependent claims 6/13 refer to α₂.

Uncertainty and internal-text anomalies (reported literally, not corrected)

1. Claim-drafting inconsistency. Claims 5 and 12 write the second coefficient as k₂ in the equation, while their own "where" clauses and dependent claims 6 and 13 refer to α₂. The specification's analogous equation (equation 7) uses α₂. I am reporting the claim text as issued; I am not resolving which symbol was intended.
2. Claim 10 formatting. The equation in claim 10 closes only one parenthesis level and contains an "×" that does not appear in claim 3's otherwise parallel formula. This appears to be a typographical defect in the printed claim.
3. Figure 5 legend discrepancy across renderings. The Google Patents HTML text and the description both describe FIG. 5 as "K_D versus Time illustrating convergence of K_D." One scraped PDF text rendering of the same document instead rendered FIG. 5 as "K_p versus Time illustrating convergence of K_p." Given the description, equations, and worked data (K_D converging to ~17, ~22, and ~35 at 1150, 1050, and 850 rpm), the K_D reading is the coherent one; the K_p rendering appears to be a text-extraction artifact. Flagging because you instructed me not to silently normalize identifiers.
4. Symbol variance in the description. The specification refers to "the PTD controller 16" in one passage where "PID controller" is clearly meant, and uses "w_a" in one place where "w_d" (desired speed) appears elsewhere. These are transcription-level inconsistencies in the source document.
5. No 2026 CAFC docket entry located. My searches returned no appeal, IPR, PGR, or district-court matter identifying US 6591808. I do not have authoritative confirmation that none exists.

Context worth keeping (grounded in the document)

• Two prior-art references are expressly framed as the closest art: US 5,213,077 (Nishizawa et al., gain-adjusting device for a PID controller controlling engine rotational speed, using fuzzy inference) and US 6,039,028 (Stuntz et al., Ford, "Active engine speed pulsation damping," using feedforward + feedback components). Seven references are cited in total (also US 4,656,986; US 4,699,097; US 5,185,543; US 5,537,967; US 6,098,593).
• Two non-patent citations: Badreddine et al., "Active Damping of Engine Idle Speed Oscillation by Applying Adaptive PID Control," SAE World Congress, March 2001; and Brandt et al., "Adaptive Interaction And Its Application To Neural Networks," Information Sciences 121 (1999), pp. 201–215 — the latter being the stated basis for the adaptation law of equation 1.
• Experimental basis: a 1.8 L indirect-injection diesel with an 8 kW starter/alternator induction machine as the supplemental torque source. Reported result: roughly 65% pulsation reduction at 850 rpm, with K_D converging bidirectionally to about 35 (850 rpm), 22 (1050 rpm), and 17 (1150 rpm).
• The patent has been cited by later work on adaptive PID control, notably US 9,507,365 B2 and US 10,359,798 B2 (Woodward, Inc., adaptive PID control for industrial turbines) and US 9,287,817 B2 (Industrial Technology Research Institute).

I'll search for litigation involving US patent 6591808 across the specified sources.

Let me search the specialized litigation databases directly.

Search performed

I ran targeted queries against Google Patents, CourtListener/Justia dockets, Docket Alarm, PACER Monitor, the Unified Patents portal (including its litigation/case-list pages), and general web sources, looking specifically for the literal string 6591808 and its formatted variants ("6,591,808"). I did not search for or include similar/adjacent patent numbers.

Result: No known litigation

I found no litigation, and no post-grant patent-office proceeding, involving U.S. Patent No. 6,591,808.

Specifically, the searches returned no district court case (no plaintiff/defendant pair, no case number, no jurisdiction, no filing date), no ITC Section 337 investigation, no Federal Circuit appeal, and no PTAB proceeding (IPR/PGR/CBM) in which US 6,591,808 was an asserted or challenged patent.

For completeness, the "6591808" hits that did surface were unrelated to this patent and should not be mistaken for litigation:

• An NSA FOIA document ID "6591808" (CLArion newsletter release) — an agency document control number, not a patent.
• A Swiss property-registry publication number in Ticino's official gazette.
• A coordinate pair and a CBC News URL slug.
• Russian-language academic articles citing US 6,591,808 B2 as prior art — these are technical citations, not litigation.

What the record does show about this patent

• Patent: US 6,591,808 B2, "Adaptive PID control method and system for internal combustion engine rotation speed pulsation damping."
• Assignee/owner: Ford Global Technologies, LLC (originally Ford Global Technologies, Inc.; inventor assignment from Ford Motor Company; named inventors Feng Lin, Alexander T. Zaremba, Bader Badreddine, Jing Sun).
• Application: US 09/967,118; filed 2001-10-01; priority 2001-10-01; published as US 2003/0065439 A1 (2003-04-03); granted 2003-07-15.
• Status: Expired – Lifetime; adjusted expiration 2021-10-12. Expiration is corroborated by maintenance-fee records (4th, 8th, and 12th-year fees paid 2006, 2010, and 2014).
• Forward citations (not litigation): US 9,287,817 B2 (Industrial Technology Research Institute), US 9,507,365 B2 and US 10,359,798 B2 (Woodward, Inc.), and CN 113635903 B (Beijing Foton Cummins Engine Co.). These are citations in later patents' specification/prosecution, not lawsuits.
• Family: Single member (US 09/967,118), one country (US) — no foreign counterparts that could have generated foreign enforcement actions.

Important caveats on reliability

1. I could not directly and exhaustively query PACER, Docket Navigator, Lex Machina, or the Unified Patents litigation case-list — those are paywalled or require interactive querying. My searches were web-index-based, so a sealed, very recent, or poorly indexed complaint could theoretically have been missed.
2. The patent's profile makes litigation unlikely: it is a Ford-owned, engine-idle-damping control patent that expired in October 2021. It was never assigned to a non-practicing entity, which is the typical precursor to assertion campaigns.
3. I am not aware of any Federal Circuit decision construing or otherwise addressing US 6,591,808. If you need a definitive negative, the authoritative check is a docket-number search by patent number in Docket Navigator or Lex Machina, plus a PACER "all courts" search — I could not run those directly.

Bottom line: Based on the sources available to me, there is no record of any litigation involving US Patent 6,591,808. State it as "no known litigation" rather than an absolute negative, given the access limitations noted above.

I'll verify the structured "no proceedings" signal against public sources before drafting.

PTAB / AIA Trial Activity — U.S. Patent No. 6,591,808 B2

Patent: Adaptive PID control method and system for internal combustion engine rotation speed pulsation damping
Patent Owner at issue: Ford Global Technologies, LLC (Dearborn, MI) — originally Ford Global Technologies, Inc.; assignment recorded from Ford Motor Company
Inventors: Feng Lin; Alexander T. Zaremba; Bader Badreddine; Jing Sun
App. No.: 09/967,118 · Filed: 2001-10-01 · Granted: 2003-07-15 · 14 claims (claims 1‑7 method; claims 8‑14 system)
Legal status (Google Patents / ODP): Expired – Lifetime; adjusted expiration 2021-10-12

Proceedings overview

Total AIA trial proceedings on file: zero (0). There are no inter partes reviews, no post-grant reviews, and no covered business method reviews — no active proceedings, no claims invalidated, no claims sustained, no settlements, and no institution denials. The USPTO Open Data Portal returns an empty AIA‑trial set for this patent, and my independent web checks (PTAB decision databases, CourtListener/Federal Circuit dockets, Google Patents' "Cited By / Cited By third party" tables) surfaced nothing either. Bottom line for a defendant: this patent was never stress‑tested at the PTAB — but that hardly matters, because it expired 2021‑10‑12 and is not assertable for any prospective conduct. The operative defense is a date defense, not an invalidity defense.

No proceedings to itemize

Because the structured data contains no proceeding numbers, I am not going to manufacture any. What follows is the verified negative plus everything a defendant actually needs to know about this patent's procedural history.

Why the absence is unremarkable here:

• PGR was never available. PGR under 35 U.S.C. §§ 321‑329 applies only to patents with an effective filing date on or after 2013‑03‑16. The '808 patent was filed 2001‑10‑01 and is pre‑AIA; it is outside the PGR window permanently.
• CBM was never available. CBM review is limited to covered business method patents (financial‑services‑related). A diesel idle‑speed pulsation damper controlling a starter/alternator does not qualify.
• IPR was technically available from 2012‑09‑16 onward, but the incentive never materialized. The patent's asserted‑value window overlapped the post‑AIA era only for about nine years, and the PTAB's § 314(a) practice weighs a patent's age and settled expectations against institution — a factor the current Director's office has applied aggressively (see the USPTO's 2025 institution‑policy change, discussed below).
• The patent term ran out before it became a litigation target. Twenty years from the 2001‑10‑01 filing date, plus the recorded adjusted expiration, put the patent out of force on 2021‑10‑12. No IPR against an expired, unasserted patent is worth the filing fee.

Related Ford patents that did attract PTAB attention (context only — not proceedings on the '808 patent): Ford's later engine‑speed / powertrain‑damping portfolio is the family the PTAB has seen, not this one. The prior art cited in the '808 patent itself is all pre‑AIA‑era: US 4,656,986 (Bosch); US 4,699,097 (Mazda); US 5,185,543 (Fichtel & Sachs); US 5,213,077 (Nishizawa/Toyota Chuo Kenkyusho); US 5,537,967 (Nippondenso); US 6,039,028 (Stuntz/Ford Global Technologies); US 6,098,593 (DaimlerChrysler). The two non‑patent citations are Badreddine et al., Active Damping of Engine Idle Speed Oscillation by Applying Adaptive PID Control, SAE World Congress, Mar. 2001, and Brandt et al., Adaptive Interaction And Its Application To Neural Networks, Information Sciences 121 (1999) 201‑215.

Non‑PTAB validity events I could not confirm — flag these for manual verification

The "PTAB proceedings on file" block covers AIA trials only. It does not cover ex parte reexamination, reissue, or district court validity adjudications. I searched for these and found no evidence of any — but absence of search hits is not proof of absence, and the ODP block is not the right instrument for those records. Verify directly at USPTO PatentCenter and via a docket search before relying on it.

Strategic summary

Claim status: all 14 claims UNTESTED, none canceled, none sustained. There is no Final Written Decision covering any claim of the '808 patent, so nothing is dead and nothing is confirmed. Claim 1 (the method claim) and claim 8 (the system claim) stand exactly as issued — never construed by the PTAB, never held unpatentable, never affirmed. Claims 2 and 9 (limiting the single adapted PID parameter to KD), claims 3/10 and 5/12 (the two control algorithms), claims 4/11 and 6/13 (the numeric ranges: γ₁ ≈ 100‑1200, α₁ ≈ 1E‑4 to 1E‑7; γ₂ ≈ 0.01‑5, α₂ ≈ 1E‑1 to 1E‑3), and claims 7/14 (vehicle environment) are likewise untouched. If you are reading this because someone sent a demand letter citing the '808 patent, the single most useful fact is not a claim outcome — it is the expiration date.

Estoppel landscape: there is none. Section 315(e)(2) estoppel attaches only after a Final Written Decision. Because no IPR was ever instituted, let alone decided, no petitioner, real party in interest, or privy is estopped as to any ground on any claim. Any party — including a party that previously considered and abandoned a petition — remains free to raise § 102 and § 103 grounds on patents and printed publications in district court or in a fresh IPR petition, subject only to the ordinary § 315(b) one‑year bar and the newly centralised discretionary‑denial regime. Practically, every prior‑art ground is "still available," but nearly all of them are moot given the patent's expired status. (Caveat: the '808 patent is prior art against others — third parties cite it, and it appears in the prosecution histories of US 9,287,817, US 9,507,365, and US 10,359,798.)

Pattern signals: none of the PTAB patterns apply. The same petitioner never filed multiple IPRs against this patent (no petitioner ever filed one). The patent owner never pursued a PTAB appeal (no FWD to appeal). There is no defensive‑aggregator trial — Unified Patents and similar entities have challenged Ford patents elsewhere, but nothing on the '808 patent appears in the record. The '808 patent's real footprint is citation‑based rather than litigation‑based: it is cited as background art in the Woodward adaptive‑PID turbine patents (US 9,507,365 / US 10,359,798) and in US 9,287,817.

Recommended next steps

1. Lead with expiration, not invalidity. The '808 patent expired 2021‑10‑12 (adjusted expiration; "Expired – Lifetime"). It cannot be infringed by any conduct occurring after that date. Any infringement theory must be built on acts within the six‑year damages lookback of 35 U.S.C. § 286 — and because the patent died in October 2021, the recoverable window closed at the latest on 2021‑10‑12. Compute the actual § 286 window against the filing date of any complaint and demand proof of pre‑expiration, post‑lookback‑cutoff conduct.
2. Confirm the laches/limitations posture. A plaintiff asserting an expired patent today is limited to backward‑looking damages. Section 286's six‑year bar combined with the 2021 expiration means the allegation must rest on conduct in a closed, shrinking historical window.
3. Verify non‑PTAB proceedings manually. PatentCenter and the PTAB E2E system are the right sources for ex parte reexamination, reissue, and any certificate of correction. PTAB E2E: https://ptacts.uspto.gov/ptabweb/ and PatentCenter: https://patentcenter.uspto.gov/ . The ODP AIA‑trial block is silent on these by design.
4. If you nonetheless want an IPR on the merits (e.g., for a co‑pending case where validity is somehow still live): note that no estoppel bars you, but weigh the changed institution landscape. Under Director Squires' 2025‑10‑16 memorandum, institution decisions in all IPR and PGR proceedings are now made by the Director, in consultation with at least three PTAB judges, via a "summary notice" — and settled expectations/patent age are heavily weighted against institution, with roughly 60% of 2025 discretionary‑denial decisions resting at least partly on that factor. An IPR petition against a 2001‑filed, 2021‑expired patent with no litigation history is close to a guaranteed discretionary denial. See https://www.willkie.com/publications/2025/10/ptab-announces-new-institution-policy .
5. If a demand letter cites specific claims, respond by demanding the pre‑expiration damages theory. Since no claim has ever been canceled or adjudicated, the patent owner cannot be attacked on estoppel or on a PTAB record — you must attack the damages window and the infringement showing itself. There is no FWD to link to and no claim to quote as dead; do not represent otherwise in correspondence or briefing.

Confidence and sourcing note. The "no AIA trial proceedings" conclusion is supported by both the structured USPTO ODP block supplied in this prompt (canonical) and independent web searches. Facts about claim count, claim structure, statutory dates, assignees, prior art, and expiration are taken from the full patent text at https://patents.google.com/patent/[US6591808](/patent/US6591808)/en (fetched 2026‑09‑23). I found no Federal Circuit docket and no district court suit involving the '808 patent in the sources searched; I did not locate any opinion to link, and I am not asserting one exists. Where the record is silent, I have said so rather than filling the gap.

I'll pull the assignment-record details from available sources before writing the analysis.

Let me try to surface the recorded correspondents for these specific reel/frame entries.

One more pass to try to pull the correspondent of record for the three Ford recordings.

Ownership Record — US 6,591,808 B2

Patent: Adaptive PID control method and system for internal combustion engine rotation speed pulsation damping
App.: 09/967,118 · filed 2001-10-01 · granted 2003-07-15 · expired 2021-10-12 (adjusted expiration)
Pre-grant pub.: US 2003/0065439 A1 (2003-04-03)
Current assignee of record: Ford Global Technologies, LLC

Sourcing note: everything in the Assignment timeline below is drawn from the legal-events record reproduced on the Google Patents page (which mirrors USPTO assignment data) and the cited reel/frame numbers. I could not retrieve the recorded correspondent of record for any of the three reel/frame entries from the indexed sources I was able to reach — I say so explicitly rather than guess. The one datum I did surface about Ford correspondents is labeled as corroborating context, not as a record for this patent.

Inventors

Determination basis: all three assignors on reel 012639/0770 conveyed to a Ford entity, and the patent's own non-patent citation is Badreddine et al., "Active Damping of Engine Idle Speed Oscillation by Applying Adaptive PID Control," SAE World Congress, Mar. 2001, Detroit, MI — an SAE paper attributed to the same Ford research group. The patent's specification also states the data were taken on a "1.8 liter indirect diesel fuel injected engine" mated to an "8 kilowatt starter/alternator induction machine," i.e., an in-house Ford development mule. That is consistent with all four inventors being Ford employees.

Pattern notes (unusual items, flagged not inferred):

• Inventor assignment recorded ~10 months after execution and ~5 months after filing. Reel 012639/0770 shows signatures executed 2001-04-03 to 2001-04-05, but the instrument was not recorded until 2002-02-22. Routine for large corporate filers; it is not evidence of a distressed transfer.
• Only 3 of 4 inventors appear as assignors on reel 012639/0770. Feng Lin does not appear on that inventor→company instrument. Ford's corporate-to-subsidiary instruments (reel 012264/0425) sweep in all employee inventions regardless, so this is most likely a paperwork split rather than a retained personal interest — but I cannot verify a separate Lin assignment from the records available, so it is an open gap rather than a finding.
• No inventor departure pattern is visible in the assignment record. The 12-month post-filing departure tell cannot be evaluated from assignment data alone; nothing in the record suggests a portfolio fire-sale (which would require a subsequent transfer, and there is none).

Original assignee

• Entity named on the issued patent: Ford Global Technologies, LLC — a Ford Motor Company subsidiary and the captive IP-holding vehicle for Ford's worldwide patent portfolio, at One Parklane Boulevard (Suite 600, Parklane Towers East), Dearborn, Michigan 48126.
• Product embodying the claims: Ford is an operating automaker; the claimed subject matter (adaptive PID damping of engine idle-speed pulsation via a starter/alternator supplemental torque source) was reduced to practice on a Ford-specification 1.8 L indirect-injection diesel engine, per the specification. Whether the specific adaptive-K_D control law ever shipped as a production calibration is not determinable from the patent or the assignment record.
• Primary line of business: vehicle design, manufacture and sale (Ford Motor Company, NYSE: F). The assignee-of-record, Ford Global Technologies, LLC, is an IP-holding subsidiary, not a licensing-only shell — it takes assignments of essentially every Ford-originated application.
• Current status: Operating. No bankruptcy, no Chapter 7/11 event, no sale of this patent is recorded. The patent itself is expired as of 2021-10-12.

Assignment timeline

Three recorded assignments. All are internal Ford corporate-chain instruments. There are no post-issuance transfers and no third-party assignee of any kind.

• 2001-09-06 (executed/effective) / recorded 2001-10-01 — Reel 012264/0425

  • Conveyance: Assignment (Assignment of Assignor's Interest)
  • Assignor: Ford Motor Company, a Delaware corporation
  • Assignee: Ford Global Technologies, Inc., a Delaware corporation
  • Correspondent: not retrievable from the sources I could reach for this reel. Corroborating context only (different reel, same era and same assignee family): Ford's contemporaneous recordings, e.g. reel 12329/553 (recorded 2001-11-06) and the Nov-2001 intake, list correspondent Carlos L. Hanze, Ford Global Technologies, Inc., Suite 600 – Parklane Towers East, One Parklane Blvd., Dearborn, MI — a Ford in-house IP-docketing name rather than an outside NPE-recording firm. Treat as suggestive, not as the record for reel 012264/0425.
  • Context: Internal corporate reorganization — Ford's standing transfer of employee-invention rights from the operating parent to its IP-holding subsidiary.

• 2001-04-03 to 2001-04-05 (executed) / recorded 2002-02-22 — Reel 012639/0770

  • Conveyance: Assignment (Assignment of Assignors' Interest)
  • Assignor: Alexander T. Zaremba; Bader Badreddine; Jing Sun (individual inventors)
  • Assignee: recorded as "Ford Motor Corporation, a corp. of Delaware" (Michigan correspondence address). Flagged as an anomaly: the indexed legal-event text reads "Ford Motor Corporation," where the Ford operating parent is Ford Motor Company. The record as indexed is what it is; I am reporting it literally and not auto-correcting it. Practically this is Ford's standard inventor-to-parent instrument.
  • Correspondent: not retrievable for this reel.
  • Context: Employee-invention assignment — routine employment-agreement conveyance, executed before filing and recorded after.

• 2003-03-01 (effective) / recorded 2003-04-22 — Reel 013987/0838

  • Conveyance: Merger (not a sale)
  • Assignor: Ford Global Technologies, Inc.
  • Assignee: Ford Global Technologies, LLC, Michigan
  • Correspondent: not retrievable for this reel.
  • Context: Internal reorganization / change of entity form only — FGTL, Inc. merged into FGTL, LLC; no change in ultimate beneficial ownership (Ford Motor Company throughout).

• 2006-12-18 / 2010-12-28 / 2014-12-29 — maintenance-fee payments (years 4, 8, 12) recorded against the patent. No conveyance of any kind after 2003-04-22.

• 2021-10-12 — adjusted expiration. No assignment accompanies the lapse.

Timeline diagram

timeline
    title Ownership of US 6591808
    2001 : Filed 01 Oct by Ford Motor Company
         : Inventors assigned rights to Ford
         : Corporate transfer to FGTL Inc
    2002 : Inventor assignment recorded 22 Feb
    2003 : Patent issued 15 Jul
         : Merger into Ford Global Technologies LLC
    2014 : Final maintenance fee paid
    2021 : Patent expired 12 Oct

NPE / troll-pattern signals

1. Shell-entity transfer — Not present. The only LLC in the chain, Ford Global Technologies, LLC (reel 013987/0838, effective 2003-03-01), is a wholly owned Ford Motor Company subsidiary whose address of record is Ford's own Parklane Towers East office, Dearborn, MI — not a registered-agent maildrop. The instrument is a merger, not a sale, and the transferor (FGTL, Inc.) was already Ford's IP holder. No single-purpose Texas/Delaware assertion LLC appears anywhere.

2. Known asserter in the chain — Not present. No assignee in the record matches Acacia, Marathon, Intellectual Ventures, IPNav, Wi-LAN, Mosaid/Conversant, Vringo, Pendrell, Innovatio, MPHJ, Lumen View, Round Rock, Document Generation Corp, or any Spangenberg entity. The chain begins and ends with Ford Motor Company's own subsidiaries.

3. Repeat correspondent across the chain — Unclear / not determinable. I could not obtain the correspondent of record for reels 012264/0425, 012639/0770 or 013987/0838, so recurrence cannot be assessed. What can be said: the assignee addresses are all Ford's Dearborn IP address, and contemporaneous Ford recordings of that era (e.g. reel 12329/553) name an in-house Ford correspondent (Carlos L. Hanze, Ford Global Technologies, Inc.) rather than a serial NPE-recording attorney — the opposite of the pattern this signal is designed to catch. Because this is a different reel, I score the signal unclear, not "not present."

4. Cascading transfers — Not present. Three recordings spread over ~19 months, all intra-Ford, ending in 2003. No chained LLC-to-LLC sequence, no shared-anonymous-principal structure.

5. Pre-litigation transfer — Not present. No infringement suit naming US 6,591,808 surfaced in the sources checked, and there is no transfer after 2003-04-22 to attach to any suit date. Note the reverse of the classic pattern: the first recording (reel 012264/0425) predates issuance by ~21 months and the patent has been expired since 2021.

6. Bankruptcy fire-sale — Not present. No Chapter 7/11 event for Ford Motor Company or Ford Global Technologies in this chain; no sale instrument recorded. (Ford's 2006–2008 restructuring did not involve a patent divestiture recorded against this patent.)

7. Privateering — Not present. No transfer to a third-party assertion vehicle; the patent never left Ford's corporate family.

8. Defensive aggregator (anti-NPE) — Not present. The chain does not terminate at RPX, AST, LOT Network, Unified Patents or OIN. It terminates at Ford Global Technologies, LLC, and then at expiration.

Verdict

Insufficient data — in the specific sense that the record contains only the original assignment chain: three recordings (reels 012264/0425, 012639/0770, 013987/0838) all internal to Ford Motor Company and its captive IP holder, the last of which is a 2003 merger, with zero post-issuance conveyances and no litigation surfaced. There is no NPE evidence to weigh and no third-party assignee to evaluate, so no NPE category can be affirmatively assigned.

It is worth stating plainly what the absence means here: this is a clean captive-portfolio patent. It was never sold, never asserted, and it expired on 2021-10-12 while still held by Ford Global Technologies, LLC. For the record, Ford Global Technologies, LLC is not an NPE — the "IP-holding subsidiary" name suffix is the exact situation in which naming alone would mislead; the entity holds Ford's entire worldwide portfolio and its only recorded transaction here is a merger of Ford's own two holding companies.

Verification links:

• USPTO Patent Assignment Search (Assignment Center): https://assignmentcenter.uspto.gov/ (search 09/967,118 or 6591808)
• Legacy USPTO Assignments on the Web (assignment.uspto.gov): https://assignment.uspto.gov/patent/index.html
• Google Patents record with legal events: https://patents.google.com/patent/US6591808/en (reels 012264/0425, 012639/0770, 013987/0838)
• USPTO Patent Center / ODP for app. 09/967,118: https://patentcenter.uspto.gov/

Caveat on completeness: the correspondents of record for all three reels are genuinely missing from this report because I could not retrieve them, not because they are absent from USPTO's database. Anyone relying on the "repeat correspondent" signal for this chain should pull the three reel/frame PDFs directly from Assignment Center, where the correspondent name and address are printed on the face of each instrument.

I'll verify the citation record and gather details on each prior-art reference for US 6,591,808.

Now let me verify the remaining cited references and the non-patent literature.

Scope note and record confirmation

I searched the USPTO record as mirrored on Google Patents (which reproduces the USPTO front page, "References Cited" / "Patent Citations" and "Non-Patent Citations" sections). The record for US 6,591,808 B2 is confirmed exactly as given in the authoritative full text:

• Application US 09/967,118; filed 2001-10-01; priority 2001-10-01; granted 2003-07-15; published as US 2003/0065439 A1 (2003-04-03).
• Assignee Ford Global Technologies, LLC (orig. Ford Global Technologies, Inc.).
• References Cited = 7 U.S. patents + 2 non-patent publications. Source: https://patents.google.com/patent/US6591808/en

Important framing point before the per-reference analysis: the patent's own Background of the Invention mentions only two references (US 5,213,077 Nishizawa et al. and US 6,039,028 Stuntz et al.). The other five are prosecution/IDS citations that appear on the front page but are not discussed in the specification. This distinction matters for the §102 analysis below — a citation in an IDS is not an admission that it anticipates; it is simply "considered."

Status of every cited reference as §102 art (pre-AIA, since filed 2001-10-01): all seven U.S. patents published between 1987 and 2000 — more than one year before the 2001-10-01 filing — so all seven qualify as §102(b) printed publications.

The seven patent citations — citation, dates, description, §102 relevance

1. US 4,656,986 — Kull et al. (Robert Bosch GmbH)

• Title: "Device for modifying operation of regulator for setting fuel quantity in an internal combustion engine operating with self-ignition"
• Priority 1983-12-03 (DE 3343854); filed (US) 1984-11-09; issued 1987-04-14. Appl. No. 670,144.
• Description: A "jolt damping circuit" for diesel (self-ignition) fuel metering. It includes a guide regulator (PI), a jolt-disturbance signal generator responsive to engine rotary speed, and a summing stage feeding an end-stage regulator — expressly including a PID regulator (block 30) — that positions the fuel-quantity setting member of an injection pump. Purpose is to damp 1–8 Hz jerk/jolt oscillations of the engine on its mounts. Source: https://patents.google.com/patent/[US4656986A](/patent/US4656986A)
• §102 relevance to 6,591,808: Overlaps claims 1/8 only on the abstract notions of engine-speed-responsive closed-loop damping and a PID regulator in the control path. It is missing: (i) a supplemental torque source coupled to the crankshaft (it actuates a fuel-injection pump setting member, not an added torque machine); (ii) continuous input of the supplied supplemental torque u to the PID; (iii) adjustment of a single PID parameter (K_D); (iv) the adaptive-interaction control algorithm. → Not an anticipator; §103/background art.

2. US 4,699,097 — Mazda Motor Corporation

• Title: "Means for suppressing engine output torque fluctuations"
• Priority/filed 1984-08-31; issued 1987-10-13.
• Description: Engine-output torque-fluctuation suppression (anti-torque-oscillation engine control). Descriptive detail is drawn from the title/front-matter only — I was unable to open the full text within the search budget, and I am flagging that rather than paraphrasing content I did not read. Source: https://patents.google.com/patent/[US4699097A](/patent/US4699097A)
• §102 relevance: At most a general §102(b)/§103 showing that suppressing engine torque/speed fluctuations was known. It does not disclose a PID controller, a supplemental torque source, or single-parameter adaptive tuning. → Not an anticipator.

3. US 5,185,543 — Fichtel & Sachs AG

• Title: "Motor vehicle drive line torsional vibration damper"
• Priority/filed 1990-02-27; issued 1993-02-09.
• Description: A drive-line torsional vibration damper — a mechanical/driveline art reference, not an electronic PID control reference. Based on title/front-matter (full text not opened).
• §102 relevance: Relevant only as background showing torsional/driveline vibration damping was known. Discloses none of the control-elements of claims 1–14. → Not an anticipator.

4. US 5,213,077 — Nishizawa et al. (Kabushiki Kaisha Toyota Chuo Kenkyusho; Kabushiki Kaisha Toyoda Jidoshokki Seisakusho)

• Title: "Gain adjusting device for PID controller for controlling rotational speed of internal combustion engine"
• Priority 1991-05-15; filed (US) 1992-05-15, Appl. No. 883,536; issued 1993-05-25.
• Description (verified): A PID controller for engine rotational speed whose gain is adjusted using fuzzy inference. A rule base of IF-THEN rules (settling time, overshoot, damping of oscillations) infers an amount of gain adjustment, applied by weighted average, and the rules are corrected to broaden the permissible range when characteristic variables cannot be held within it. The stated problem is that in low-speed ranges the gain "cannot be made to converge." Source: https://patents.google.com/patent/US5213077 (PDF: https://patentimages.storage.googleapis.com/0a/fd/69/578738c75a87fa/US5213077.pdf)
• §102 relevance: This is the closest "PID-for-engine-speed-damping" reference and is the first reference distinguished in the 6,591,808 Background. It is a plausible §102(b) candidate only against a hypothetical claim stripped of the supplemental-torque-source and single-parameter limitations, because it lacks: (i) a supplemental torque source (it adjusts the PID loop that controls engine speed, not a torque machine on the crankshaft); (ii) a single PID control parameter — it adjusts gains on P, I and/or D (fuzzy rules explicitly adjust proportional, integral and derivative gains); (iii) the adaptive-interaction law that adjusts a parameter as a function of error e and supplied torque u. → Not an anticipator of claims 1–14; primary §103 art.

5. US 5,537,967 — Nippondenso Co., Ltd.

• Title: "Vibration damping control apparatus for vehicle"
• Priority/filed 1992-12-28; issued 1996-07-23.
• Description (verified): A rotary electric machine (generator-motor) connected to the engine produces a torque variation of the same frequency as the vehicle vibration, in opposite phase, to cancel it. Control uses a ROM storing a plurality of operation modes, selected based on the detected primary-frequency vibration component and a crank-angle-relative phase difference (and, in claim variations, on passenger position/payload). The machine may be connected to the engine flywheel. Source: https://patents.google.com/patent/US5537967
• §102 relevance: Notably, this reference does disclose an electric machine supplying a cancelling torque to the engine/crankshaft — i.e., the general concept of an active supplemental torque source. But it is missing: (i) a PID controller controlling that machine; (ii) continuous input of desired speed, observed speed and the supplemental torque into a PID; (iii) adjustment of a single PID control parameter via a control algorithm. Its control is a pre-stored operation-mode / phase-lookup scheme, not an adaptive PID. → Not an anticipator; §103 art supporting the "supplemental torque source for pulsation damping" element.

6. US 6,039,028 — Stuntz et al. (Ford Global Technologies, Inc.)

• Title: "Active engine speed pulsation damping"
• Priority/filed 1999-01-14; issued 2000-03-21.
• Description (verified): Uses a starter/alternator as a supplemental torque source on the engine crankshaft to reduce engine speed pulsations at idle. The control comprises a linear feedback term (a function of the difference between target speed ω_d and actual speed ω) plus a learning feedforward term computed at each crankshaft rotation via a learning rule (gradient-type; u = u_f − u_a), exploiting periodicity in the crank-angle domain. Source: https://patents.google.com/patent/US6039028
• §102 relevance: This is the closest reference on the "field and goal" axis (same assignee, same problem, same supplemental-torque architecture) and is the second reference distinguished in the 6,591,808 Background. It is a potential §102(b) target only for the broadest claims 1/8 if the "PID controller" and "single PID control parameter" limitations were read out of the claim — which they cannot be. It is missing: (i) a PID controller (its controller is a proportional-type feedback law plus iterative learning feedforward, no integral or derivative channel); (ii) adjustment of a single PID parameter K_D; (iii) the specific adaptation equations of claims 3/5/10/12 and the coefficient ranges of claims 4/6/11/13. → Not an anticipator of claims 1–14; the single most important §103 reference, and the closest commercial/technical neighbor.

7. US 6,098,593 — DaimlerChrysler AG

• Title: "Electronic bucking damping device for internal-combustion engines"
• Priority/filed 1997-05-28; issued 2000-08-08.
• Description: Electronic damping of bucking (driveline judder/jerk) via engine control. Based on title/front-matter (full text not opened).
• §102 relevance: Shows electronic damping of engine/driveline oscillations was known. Discloses none of the PID/supplemental-torque/single-parameter elements. → Not an anticipator; §103 background.

The two non-patent citations

NPL-1 — Badreddine et al., "Active Damping of Engine Idle Speed Oscillation by Applying Adaptive PID Control," SAE World Congress, March 2001, Detroit, MI

• This is the most material item in the entire citation list for §102 purposes, because it is the inventors' own paper describing the adaptive PID control of the same system, published about seven months before the 2001-10-01 filing, and it is cited on the face of the patent.
• Timing consequences: Because it published less than one year before filing, it is not a §102(b) statutory bar. It could only be §102(a)/(pre-AIA "printed publication before the invention thereof") art if the invention date post-dates March 2001 — note the assignment execution dates in the record run 2001-04-03 to 2001-04-05, which are after the SAE paper. See https://patents.google.com/patent/US6591808/en (Legal Events; Assignors Zaremba, Badreddine, Sun). I flag this as a prosecution-risk nuance, not a conclusion, since the legal invention date is not established by the assignment signing date.
• §102 relevance: Potentially anticipatory of the algorithm claims (3–6, 10–13) in substance (it discloses the adaptive PID tuning applied to idle-speed pulsation damping), but its self-publication/grace-period posture makes it, in practice, a §102(a) risk / §103 reference rather than a clean §102(b) bar.

NPL-2 — Brandt et al., "Adaptive Interaction And Its Application To Neural Networks," Information Sciences 121 (1999), pp. 201–215

• Cited in the specification as the basis for Equation 1 (the adaptive-interaction adaptation law). Published 1999 → §102(b) art.
• §102 relevance: It discloses the adaptation law itself (the dk/dt = −γ(dE/dw)∘F[u]∘y structure) but not its application to an internal-combustion-engine PID controller driving a supplemental torque source. → §103 art that supplies the missing algorithmic element; not an anticipator of any claim as a whole.
• (The specification also relies on D. G. Luemberger, Optimization By Vector Space Methods, Wiley, 1968, for the Fréchet-derivative background — a further §102(b) general-knowledge reference, not cited on the front page.)

Consolidated claim-mapping (which claims each item could potentially reach under §102)

Claims 3–6 and 10–13 (the specific Equations 6/7 and the α/γ coefficient ranges) are anticipated by none of the cited patent references. The only cited item that comes close in substance is the inventors' own SAE paper (NPL-1). The broadest independent claims 1 and 8 require three things none of the seven patents supplies in a single reference: (a) a supplemental torque source on the crankshaft, (b) a PID controller receiving desired speed, observed speed and the supplemental torque, and (c) adaptation of a single PID parameter via a control algorithm to damp pulsation.

Bottom line for the §102 question

• No cited reference anticipates claims 1–14 as a whole. Each of the seven patents is best characterized as §102(b) prior art usable for §103 obviousness, and the four most technically relevant (US 5,213,077, US 6,039,028, US 5,537,967, US 4,656,986) map onto different, non-overlapping elements.
• The strongest §103 combination would be: US 5,213,077 (PID controller for engine speed with gain adjustment to damp oscillation) + US 6,039,028 or US 5,537,967 (supplemental torque source — starter/alternator or rotary electric machine — providing cancellation torque to the crankshaft for idle-speed pulsation damping) + Brandt et al. 1999 (the adaptive-interaction parameter-adaptation law). That is the combination the patent's own Background and Equation-1 citation effectively concede as the state of the art.
• The single highest-value §102 flag is NPL-1 (Badreddine et al., SAE World Congress, March 2001). It is the inventors' own paper on the same subject and is the only citation that could plausibly read on the algorithm claims — but its <1-year-to-filing timing means it is not a §102(b) bar; treat it as a §102(a) / §103 concern.

Caveats on reliability

1. I opened full text for US 4,656,986, US 5,213,077, US 5,537,967 and US 6,039,028. For US 4,699,097, US 5,185,543 and US 6,098,593 I could retrieve only front-matter/title/date data within the search budget; their descriptions above are drawn from titles and are flagged accordingly — a full-text read is needed for a definitive §102 characterization.
2. This analysis uses the Google Patents mirror of the USPTO record; the authoritative documents are the granted patent PDF and the file wrapper at USPTO Patent Center (https://patentcenter.uspto.gov).
3. Pre-AIA §102/§103 is applied because the application was filed 2001-10-01 (before the AIA first-inventor-to-file provisions).
4. No contradiction found with the previously generated litigation summary: its forward-citation list (US 9,287,817; US 9,507,365; US 10,359,798; CN 113635903 B) and status data match the authoritative text. Minor date note: the task header says "Current Date: April 26, 2026," while the fetched record is timestamped 2026-09-23; this does not affect any conclusion above.

I'll ground the § 103 analysis in the actual prior-art references listed on the patent page before building combinations.

Obviousness Analysis — US 6,591,808 B2 under 35 U.S.C. § 103

Analytical note on the framework. US 09/967,118 was filed 2001‑10‑01 with no earlier priority claim (the Google Patents record shows priority = filing date = 2001‑10‑01). It is therefore governed by pre‑AIA §§ 102/103, including pre‑AIA § 103(c) (common ownership), which materially affects one of the references below. The effective critical date for § 102(b) art is 1999‑10‑01.

This section builds on, and does not repeat, the bibliographic, abstract, claim-construction, and litigation sections already generated. One prior generation must be refined: the earlier section listed the Badreddine SAE paper neutrally among "non-patent citations." I have now verified its byline, and that changes its prior‑art status (see § 2.4 below).

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

For claims 1–14 the PHOSITA is a controls/powertrain engineer holding a B.S. (or M.S.) in mechanical or electrical engineering with roughly 2–5 years of experience in automotive engine control, who is familiar with: (a) PID control and its manual/automatic tuning (Ziegler‑Nichols, one‑gain‑at‑a‑time calibration); (b) direct adaptive control and gradient/"MIT‑rule"‑type parameter adaptation; (c) starter/alternator (integrated starter‑generator) hardware and field‑oriented control of induction machines; and (d) engine idle NVH and crank‑angle‑domain speed‑pulsation measurement. The patent's own specification confirms this level: it treats Frechet derivatives, adaptive interaction, and PID tuning as conventional ("[t]he basis for equation 1 may be found within any of several texts relating to adaptive control methodology… Frechet derivatives are generally also conventional within the context of mathematical control algorithms").

2. The prior art on this page — what actually counts

2.1 References on the face / cited-by that pre‑date 2001‑10‑01

2.2 References that are not prior art (post‑date the critical date)

Everything in the page's "Cited By," "Families Citing this family," and most of "Similar Documents" post‑dates 2001‑10‑01 and is therefore unavailable as § 102/103 art against this patent: US 9,287,817 B2 (2016), US 9,507,365 B2 (2016), US 10,359,798 B2 (2019) (Woodward adaptive PID turbines), CN 113635903 B (2023). The same is true of US 9,908,521 B2, JP 2021080896 A, JP 2005016436 A, US 2004/0107034 A1, US 6,893,377 B2, KR 20040014491 A, JP 4196855 B2 (as issued publications). They are useful only as later evidence of the trajectory of the art and should not be charted into a § 103 rejection. (This is a point I flag because the page's layout invites the error of treating "cited by"/"similar" as prior art.)

For the remaining pre‑2001 "Similar Documents" (KR0154018B1 1998, JPH05312076A 1993, JPH0793037A 1995, JPH04311631A 1992, US 6,189,317 B1, US 6,192,311 B1, EP 0778559 B1, etc.) I have not independently verified claim‑level content, so I do not rely on them below; they are candidates for a secondary "idle‑speed control device" / "vibration‑noise control system" rejection.

2.3 A Ford reference not on the face of the patent (flagged, not relied on)

My search surfaced US 6,286,473 B1 (Zaremba; Ford Global Tech.; filed 2000‑03‑31; issued 2001‑09‑11) — using a starter/alternator as an "active flywheel," measuring engine speed, and applying a variable notch filter + lead compensator with a torque‑command limiter to damp crankshaft oscillations. It is closer art than several references that are cited. Two cautions: (i) it issued less than one year before 2001‑10‑01, so it is at best § 102(a)/(e) art, never § 102(b); and (ii) because it names Zaremba, a common inventor, its "by another" status and pre‑AIA § 103(c) common‑ownership disqualification are both arguable. Use it as state‑of‑the‑art evidence, not as a load‑bearing § 103 reference.

2.4 The SAE paper is not prior art — verified

Prior generations treated the SAE citation neutrally. I verified the byline: Badreddine, B., Zaremba, A., Sun, J. and Lin, F., "Active Damping of Engine Idle Speed Oscillation by Applying Adaptive PID Control," SAE 2001‑01‑0261, published March 5, 2001
(https://saemobilus.sae.org/papers/active-damping-engine-idle-speed-oscillation-applying-adaptive-pid-control-2001-01-0261 ; authors confirmed at https://www.semanticscholar.org/paper/7a02e3788d15c4c06e7e92004a87f63b39df6d62).

Those four authors are exactly the four named inventors of US 6,591,808 (Lin, Zaremba, Badreddine, Sun). Consequences:

• § 102(a): a printed publication by the same inventive entity is not "by others" and is not § 102(a) art (MPEP 2132: "by others" = a different inventive entity).
• § 102(b): publication 2001‑03‑05 is only ~7 months before the 2001‑10‑01 filing — not "more than one year prior."

So the SAE paper is not a prior‑art reference against these claims, even though its abstract discloses essentially the whole commercial embodiment (starter/alternator induction machine on the crankshaft as the actuator; on‑line APID tuning via the theory of adaptive interaction; an error function that is "a weighted combination of the plant states and the required control effort"; Frechet and approximation methods; the 1.8 L Ford diesel plus 8 kW induction machine). Had it been by "others," or filed a month later, a § 102/§ 103 rejection would be nearly automatic. It can still be used as evidence of the inventors' own possession and as an admission of what a PHOSITA knew in March 2001 — but not as a § 102(a)/(b) reference.

3. Element mapping: claim 1 (method) and claim 8 (system)

4. Proposed § 103 grounds

Ground I (primary): US 6,039,028 in view of US 5,213,077; further in view of US 6,098,593

Targets claims 1, 2, 7, 8, 9, 14 (and is the base for the algorithm claims).

• Stuntz supplies the physical architecture (engine + speed sensor + starter/alternator on the crankshaft + controller that continuously reads desired and actual crank speed and commands a supplemental torque u specifically to damp idle speed pulsation) and even the problem statement: "pulsations in the rotational speed of the engine, particularly at engine idle, can be a source of customer dissatisfaction."
• Nishizawa supplies the missing control element: a PID controller for controlling ICE rotational speed with automatic, algorithmic gain adjustment — i.e., the same controlled variable, the same plant class, and an express recognition that ICE speed control suffers "unstable" rotation in low‑speed ranges and that gains must adapt.

Motivation (KSR‑style, articulated):

1. Same field, same problem, same variable. Both references target regulation/damping of ICE rotational speed at idle; the combination is the "simple substitution of one known element (a PID speed controller with adaptive gain adjustment) for another (a linear feedback speed controller)" — KSR, 550 U.S. 398, 416–17 (2007).
2. The substitution is at the exact point of improvement. Stuntz's own summary describes its controller as a linear feedback term plus a learning feedforward term; a POSITA improving that loop would immediately recognize a PID as the standard framework ("[t]he PID Controller is still the most used control system in industries today because of its simplicity, ease of implementation and available tools for tuning," as the 2001 SAE paper — the inventors' own admission of the art — puts it).
3. No teaching away. Stuntz disparages only angular-acceleration estimation (computational complexity/noise), not PID control; Nishizawa stresses the difficulty of multi‑gain convergence, which if anything points toward narrowing what is tuned (see Ground II).
4. Predictable result. Adding proportional/integral/derivative action to a speed‑error feedback loop that already damps pulsation yields damping of the same error signal — a result the art had already achieved in the same plant.

Ground II: Ground I + US 6,098,593 (DaimlerChrysler) — the "single PID control parameter / K_D" limitations (claims 1, 2, 8, 9)

This is the crux limitation, and the record supplies a clean motivation:

• US 6,098,593 expressly reports that a differentiating filter of a specific order was found "most suitable for the bucking damping," while a proportional‑differentiating (PDT1) filter was best for load‑change (quantity) damping — i.e., the field had already identified the derivative channel as the one that damps engine‑speed oscillation, and had already uncoupled the damping functions so each could be "adjusted and optimized independently of one another."
• Nishizawa supplies the contrary teaching that motivates narrowing: its background states that when the object cannot be controlled within a permissible range, "the gain is changed toward a high‑gain side… which increases the magnitude of the oscillations to the contrary, and an attempt is subsequently made to control these oscillations by lowering the gain. This disadvantageously creates a situation in which the gain cannot be made to converge." A POSITA faced with non‑convergence from simultaneously adapting P, I and D gains has an express reason to reduce the number of simultaneously adapted gains to one — a classic "known technique (isolate and tune one loop gain at a time) applied to a known device, ready for improvement."
• Deletion of an element (the P and I adaptation) and its function is an obvious expedient where no new result is obtained — MPEP 2144.04(VI) (see In re Kuhle). Nothing in the claims requires K_P or K_I to be zero; claim 1 requires only that a single parameter be adjusted. Holding the others at fixed values while adapting one is precisely the ordinary one‑variable‑at‑a‑time PID calibration the art practiced.
• "Obvious to try." With exactly three candidate parameters and a known dominant one, the number of identified, predictable solutions is trivially small.

Ground III: Ground I or II + Brandt & Lin (1999) — algorithm claims 3/4, 10/11, 5/6, 12/13

The claimed equations are ordinary mathematics applied to a known control structure:

• Brandt & Lin (the patent's own cited basis) discloses the adaptive‑interaction adaptation rule in the form ∂K_i/∂t = −γ (∂E/∂ω) ∘ F[u] ∘ y_i, applied to decomposition of a controller into proportional, integral and derivative "devices" (this is confirmed, for the same authors' application of it, in the SAE paper's equation (6) and accompanying block diagram of the APID adaptation).
• Apply to the Stuntz plant: ω = F[u], F[u] = dω/du, and the composition F[u] ∘ y_i = g(t) * y_i where g(t) is the impulse response of the engine‑plus‑actuator to supplemental torque (the patent itself concedes the engine has a "nominally smooth impulse response," Fig. 2). Substituting into equation 1 with E = e² + α₁u² gives exactly the equation of claims 3/10 by the chain rule and the definition F[u] = du/dω — routine calculus, not invention.
• Claim 5/12's equation (dropping the convolution and the plant model) is the "approximation method," obtained by presuming a smooth impulse response. A POSITA adopting an on‑line‑computable simplification of an exact model‑dependent rule, for implementation economy and robustness to plant variation, is routine engineering with a predictable direction of effect.
• Motivation for the control‑effort term αu²: the field's concern with actuator limits and torque command saturation (a torque‑command limiter is claimed in the Ford art, and a starter/alternator has finite torque/current capability) supplies a concrete design incentive to penalize control effort in the cost function. Weighted quadratic costs of the form e² + αu² are the textbook norm.

Ground IV: Dependent numeric ranges — claims 4, 6, 11, 13

Claims 4/11 (γ₁ ≈ 100–1200, α₁ ≈ 1×10⁻⁴–1×10⁻⁷) and claims 6/13 (γ₂ ≈ 0.01–5, α₂ ≈ 1×10⁻¹–1×10⁻³) recite adaptation gains and cost weights, not structures. These are results‑effective variables, and the specification gives no evidence of criticality beyond a single 1.8 L engine: "experimentally determined," "more preferably," "most preferably." Where the art discloses the parameter generally and the claim recites a range optimized by routine experimentation, the range is obvious absent a showing of unexpected criticality (In re Aller; In re Applied Materials; KSR). The claimed ranges span one to two orders of magnitude and are preceded by "about."

Ground V: Claims 7 and 14 (transportation vehicle)

Stuntz is expressly a motor‑vehicle idle‑quality system (engine 10, drivetrain 16, starter/alternator); US 5,537,967 and US 6,098,593 are vehicle systems. One‑line rejection.

5. Where the patentee has a plausible rebuttal (and why it probably fails)

6. Statutory and formal caveats that bear on the analysis

1. Pre‑AIA § 103(c) / common ownership. US 6,039,028 is Ford‑owned and is the primary reference. Common ownership does not save the claims here, because § 103(c) disqualifies only subject matter that is prior art solely under § 102(e), (f) or (g). US 6,039,028 issued 2000‑03‑21 — more than one year before the 2001‑10‑01 filing — so it is § 102(b) art and stays fully available for § 103. Conversely, Ford's US 6,286,473 (issued 2001‑09‑11) is at most § 102(a)/(e) art and would be a candidate for § 103(c) disqualification; do not build a rejection on it.
2. Claim 5/12 and claim 10 formal defects (already flagged in the earlier section) matter here: claim 5/12's equation recites k₂ while its own "where" clause and claims 6/13 recite α₂, and claim 10's equation has an unmatched parenthesis and an "×" absent from claim 3. An equation‑based obviousness argument must be run against the claim text as issued; a rejection under § 112(b) (indefiniteness) or § 112(a) (the k₂ term has no antecedent) is the cleaner attack on those specific claims, and it may be the reason those claims would fall first.
3. The SAE paper cuts against the patentee on § 102(a)/(b) only if the byline changes. I verified four authors matching the four inventors; if any additional author were later added, or if a different inventive entity were established (recall the earlier‑flagged assignment‑record gap: the 2002‑02‑22 inventor assignment to Ford lists only Zaremba, Badreddine and Sun, not Lin), the Grace‑period/“by others” analysis should be re‑run — with the possible result that SAE 2001‑01‑0261 becomes anticipatory, not merely obviousness‑bearing.

7. Bottom line

• Claims 1, 7, 8, 9, 14: appear obvious over US 6,039,028 (Stuntz) in view of US 5,213,077 (Nishizawa), with US 6,098,593 (DaimlerChrysler) supplying the derivative‑channel focus that supports the "single PID parameter" limitation. Confidence: moderate‑to‑high, the main soft spot being express disclosure of the supplemental torque as a controller input.
• Claims 2 and 9 (K_D): obvious on the same combination plus US 6,098,593's "D‑function most suitable for the bucking damping" finding.
• Claims 3, 5, 10, 12 (the equations): obvious as the application of the Brandt & Lin (1999) adaptive‑interaction rule (which the patent itself identifies as the basis) and routine chain‑rule calculus to the Stuntz plant with a standard e² + αu² cost — subject to the § 112 defects that make 5/12 and 10 poor vehicles for an obviousness test.
• Claims 4, 6, 11, 13 (ranges): obvious as routine optimization of results‑effective variables with no demonstrated criticality.
• Strongest overall rejection package: Stuntz + Nishizawa + DaimlerChrysler for the independent claims; add Brandt & Lin for the algorithm claims; add a routine‑optimization rationale (or § 112) for the range claims.
• What would change this answer: (a) documentary evidence of an invention date before 2000‑08‑08, which would knock out US 6,098,593 as § 102(a) art (it would remain available under § 102(e)); (b) a showing of unexpected criticality for the α/γ ranges; (c) location of a pre‑1999 reference expressly teaching adaptation of a single PID gain for engine‑speed damping, which would collapse the analysis into anticipation; or (d) any change to the SAE byline analysis at § 2.4. I have not exhaustively searched non‑US/JP art, and I could not verify the content of the pre‑2001 "Similar Documents," so treat the above as the state of the record on this page rather than an exhaustive invalidity opinion.