Invalidity dossier
US 4406266
Added 9/20/2026, 5:21:14 AM
Active provider: DeepSeek · deepseek-flash
Patent summary
Title, assignee, inventors, filing/issue dates, abstract, and a plain-language overview of the claims.
Patent Overview — US 4406266 A
Title: Fuel metering and discharging apparatus for a combustion engine
Patent number / application: US 4406266 A; application US06/297,164
Inventor: Norbert W. Kiesling
Assignee: Colt Industries Operating Corp (original assignee and current assignee as listed); an assignment to Colt Industries Operating Corp. (a Delaware corporation) was recorded 1983-07-20, assigning Kiesling's interest.
Key dates: Priority/filing date 1981-08-28; application granted and published 1983-09-27; anticipated expiration 2001-08-28. Legal status listed as "Expired – Fee Related" (the listing notes legal status is an assumption, not a legal conclusion).
Purpose (per the supplied text): The invention "relates generally to fuel injection systems and more particularly to fuel injection systems and apparatus for metering fuel flow to an associated combustion engine."
Plain-language scope (per the supplied text): The description discusses prior-art efforts to meet NOx emissions standards, including exhaust gas recirculation to lower combustion temperature; overly rich fuel-air metering; ignition-timing retard; lower compression ratios; and a dual-bed catalyst approach (reducing catalyst near the engine, oxidizing catalyst downstream, with extra air supplied between the beds). It notes objections to such systems: high cost, added conduitry, air pump means, an extra catalyst bed, and a tendency to form ammonia that may or may not be reconverted to NOx in the oxidizing bed. The text also discusses fuel injection replacing carbureting apparatus, injecting fuel under superatmospheric pressure through individual nozzles directly into cylinders, and states that such systems are costly and have not proven generally successful because metered fuel flow must be provided over a very wide range — systems accurate at one end of the range being relatively inaccurate at the other.
Source: https://patents.google.com/patent/US4406266/en (fetched 2026-09-20T05:21:14.152Z)
What the excerpt does not establish: It does not provide the claims' text or the full description, the abstract, the figures/drawings, or the detailed structure of the disclosed apparatus. It therefore does not establish the precise metered elements, the injection/discharge configuration, or the claimed scope. Because the text is marked as excerpted with omitted portions, this overview is limited to the material supplied and does not assess prior art, validity, or ownership beyond the recorded assignment noted above.
Generated 10/1/2026, 10:02:46 PM
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Litigation summary
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Proceedings on file (0)
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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.
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.
Prior art
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Obviousness
Combinations of prior art that suggest the claimed invention would have been obvious under 35 U.S.C. § 103.
Extensions
Patent term adjustments, term extensions, continuations, divisionals, family members, and expiration dates.
Derivative works
Defensive disclosure: derivative variations of each claim designed to render future incremental improvements obvious or non-novel.