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Patent invalidity dossiers.

7,247 patents in the database, sorted by number of on-file litigation cases. Of these, 2,988 have at least one tracked case across 6,606 litigations.

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US4965822
0 cases1/8 sections
US4965822A — Full Duplex Speakerphone: Overview Title: Full duplex speakerphone Patent number: US4965822A Application number: US07/335,239 Inventor: Errol R. Williams Original assignee: VideoTelecom Corp (later recorded as VTEL…
View full analysis →added 9/23/2026
US496977
0 cases1/8 sections
Patent Overview: US 496,977 — "Injector" Title: Injector Patent number: US 496,977 A Inventor: Ernst Körting, of Hanover, Germany (a subject of the Emperor of Germany) Assignee: Louis Schütte, of Philadelphia, Pennsylvania Application…
View full analysis →added 9/23/2026
US4975808
0 cases1/8 sections
Patent Overview: US4975808A — "Backlighting Apparatus" Identification. US4975808A (application US07/415,741), filed and granted priority on 1989-10-02, published 1990-12-04. Inventors: David L. Bond and Kevin D. Kaschke. Original assignee…
View full analysis →added 9/23/2026
US4977594
0 cases1/8 sections
Patent Overview: US4977594A — Database usage metering and protection system and method Title: Database usage metering and protection system and method Inventor: Victor H. Shear Original/Current Assignee (as listed): Electronic Publishing…
View full analysis →added 9/23/2026
US4985710
0 cases1/8 sections
Patent Overview — US 4985710 A Title: "Buttable subunits for pagewidth 'Roofshooter' printheads" Patent number / application: US 4985710 A; Application US07/442,641 Assignee: Xerox Corp (original assignee); inventors Donald J. Drake and…
View full analysis →added 9/23/2026
US4991064
0 cases1/8 sections
Patent Overview: US 4,991,064 A Title: Silhouette lightpipe illumination for vehicle instrumentation Patent number / application: US 4,991,064 A (application US07/446,248) Inventor: James M. Clem Assignee: Delco Electronics Corporation (a…
View full analysis →added 9/23/2026
US4998241
0 cases1/8 sections
I'll verify against live sources before summarizing. Verification of identifiers I searched for the exact string 4998241 only (no truncation or normalization). Findings: - US 4,998,241 A — confirmed as "Echo canceller," Google Patents…
View full analysis →added 9/23/2026
US500466
0 cases1/8 sections
Patent Overview — US 500,466 Title: Boiler-flue expander Inventor: Leopold Biddle, of Raton, Territory of New Mexico Patent number: US 500,466 Application filed: January 14, 1893 — Serial No. 453,355 (No model) Granted/Publication date…
View full analysis →added 9/23/2026
US5005108
0 cases1/8 sections
Patent Overview — US 5005108 A Title: Thin panel illuminator Patent number: US 5005108 A Application number: US07/309,424 Inventors: David J. Pristash; Jeffery R. Parker Original assignee: Lumitex Inc. Current assignee listed (per source)…
View full analysis →added 9/23/2026
US5033048
0 cases1/8 sections
Patent Overview — US 5,033,048 A Title: Memory selftest method and apparatus same Source: https://patents.google.com/patent/US5033048/en Bibliographic data (as supplied): Application US07/525,203; filed 1990-04-19; granted and published…
View full analysis →added 9/21/2026
US5050213
0 cases1/8 sections
Patent Overview — US5050213A Title: Database usage metering and protection system and method Assignee: Electronic Publishing Resources Inc (original and current assignee as listed; a 2002 reassignment to InterTrust Technologies Corp. is…
View full analysis →added 9/23/2026
US5050946
0 cases1/8 sections
Patent Overview: US 5,050,946 — "Faceted Light Pipe" Title: Faceted light pipe Patent Number: US 5,050,946 A Inventors: Kevin J. Hathaway; Richard M. Knox, Jr.; Douglas A. Arego; Gaylon R. Kornfuerhrer Original Assignee: Compaq Computer…
View full analysis →added 9/23/2026
US5056892
0 cases1/8 sections
Patent Overview — US 5056892 A Title: Totally internally reflecting thin, flexible film Assignee/Applicant of record: Original assignee Minnesota Mining and Manufacturing Co.; current assignee listed as 3M Innovative Properties Co (per the…
View full analysis →added 9/23/2026
US5072883
0 cases1/8 sections
US5072883A — Full Cone Spray Nozzle with External Air Atomization Title: Full cone spray nozzle with external air atomization Patent number: US 5,072,883 A Inventor: Daniel A. Vidusek Assignee: Spraying Systems Co. (assignment recorded…
View full analysis →added 9/21/2026
US5086429
0 cases1/8 sections
Patent Overview: US 5,086,429 A Title: Fault-tolerant digital computing system with reduced memory redundancy Patent number: US5086429A Application number: US07/506,714 Inventors: Scott L. Gray; Steven R. Thompson Assignee: Honeywell Inc…
View full analysis →added 9/23/2026
US5098925
0 cases1/8 sections
Patent Overview — US5098925A Title: Spiro-dihydroisoindole compounds Patent number: US5098925A Application number: US07/650,503 Inventor: Thomas M. Bare Original assignee: ICI Americas Inc. Current assignee (as listed): Zeneca Inc…
View full analysis →added 9/23/2026
US5099511
0 cases1/8 sections
Patent Overview — US5099511A Title: Exchange system for incoming calls from direct-in lines Patent number: US5099511A (application US07/448,840) Assignee: Fujitsu Ltd (original assignee; assignment recorded 1989-12-12, assignor Masaharu…
View full analysis →added 9/23/2026
US5112298
0 cases1/8 sections
Patent Overview: US 5,112,298 A — "Apheresis Method and Device" Bibliographic data (from supplied text): - Patent number: US 5,112,298 A - Application number: US 07/542,846 - Filing date / priority date: 1990-06-25 - Publication (grant)…
View full analysis →added 9/23/2026
US5114204
0 cases1/8 sections
Patent Overview — US 5,114,204 Title: Collapsible interior sun shade for unoccupied motor vehicle Patent number: US5114204A Application number: US07/405,943 Inventor: Alfredo P. Bernardo Assignee: Individual (original and current assignee…
View full analysis →added 9/23/2026
US5120548
0 cases1/8 sections
Patent Overview — US5120548A Title: Swelling modulated polymeric drug delivery device Patent number: US5120548A | Application: US07/433,056 | Inventors: Gregory A. McClelland; Gaylen M. Zentner | Original assignee: Merck and Co Inc…
View full analysis →added 9/23/2026