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Patent invalidity dossiers.

7,175 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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  • US140327
    0 cases1/8 sections

    Patent Overview: US 140,327 — Improvement in Whiffletrees Title: Improvement in Whiffletrees Patent No.: US 140,327 Inventor: Bailey S. Wescott, of Corning, Steuben County, New York Assignee/Interests: Wescott assigned one-half his right…

    View full analysis →added 9/23/2026
  • US146265
    0 cases1/8 sections

    Patent Overview — US 146,265 Title: Improvement in Combined Bedsteads and Cribs Patentee: Charles Morgan, of Bridgeport, Fairfield County, Connecticut Patent Number: US 146,265 Application Filed: July 17, 1873 Granted/Published: January 6…

    View full analysis →added 9/20/2026
  • US147127
    0 cases1/8 sections

    Patent Overview — US 147,127 Title: Improvement in Lifting-Jacks Patentee: James T. Guthrie, of Leesburg, Ohio. No assignee is named in the supplied text. Dates: Application filed January 6, 1874; Letters Patent dated February 3, 1874 (the…

    View full analysis →added 9/24/2026
  • US153068
    0 cases1/8 sections

    Patent Overview — US 153,068 Title: Improvement in Cotton-Presses Patentee: George W. Grader, of Marblehead, Essex County, Massachusetts (spelled "GEORGE V. GRADER" in the OCR'd heading and "GEORGE XY. GRADER" in the body; the correct…

    View full analysis →added 9/24/2026
  • US1556106
    0 cases1/8 sections

    US1556106A — "Ornament": Patent Overview Title: Ornament Patent number: US1556106A Application number: US635605A Inventor: Arthur L. Hamilton, of Bellaire, Harris County, Texas Assignee: Individual (original assignee listed as Individual)…

    View full analysis →added 9/24/2026
  • US1557270
    0 cases1/8 sections

    Patent Overview — US 1557270 A Title: Vacuum cup for washing machines Inventor: William E. Pinckney, of Portland, Multnomah County, Oregon, a US citizen Assignee (per source): Individual (original assignee: Individual) Application No.: US…

    View full analysis →added 9/23/2026
  • US1592313
    0 cases1/8 sections

    Search Results Summary CAFC 2026 docket search: No results found for patent number 1592313 in any 2026 Federal Circuit docket. This is consistent with the patent's status — it expired by operation of law in 1943 (17-year term from issue)…

    View full analysis →added 8/27/2026
  • US166113
    0 cases1/8 sections

    Patent Overview — US 166,113 Title: Improvement in Nut-Locks Inventor: James M. Kent, of Curtis, Steuben County, New York Patent date: July 27, 1875 Application filed: June 19, 1875 Assignee: None stated in the supplied text Source…

    View full analysis →added 9/23/2026
  • US174931
    0 cases1/8 sections

    Patent Overview — US174931A Title: Improvement in Sectional Steam-Boilers Inventor: Valerius D. Anderson, of Springfield, Ohio Patent number: US 174,931 Dates: Application filed March 6, 1875; patent dated/issued March 21, 1876. (Google…

    View full analysis →added 9/23/2026
  • US175386
    0 cases1/8 sections

    Patent Overview — US 175,386 Title: Improvement in Sewing-Machine Treadles Patentee: William H. Stewart, of Brooklyn, county of Kings, State of New York. No assignee is named in the supplied text. Dates: Application filed September 15…

    View full analysis →added 9/21/2026
  • US176913
    0 cases1/8 sections

    Patent Overview: US176913A — "Improvement in Tuyeres" Title: Improvement in Tuyeres Patent number: US176913A Inventor: Thomas F. Witherbee, of Port Henry, County of Essex, New York Filed: February 28, 1876 Granted/Published: May 2, 1876…

    View full analysis →added 9/23/2026
  • US181074
    0 cases1/8 sections

    Patent Overview: US 181,074 — Improvement in Watch-Keys Title: Improvement in Watch-Keys Patentee: William S. Hicks, of New York, N.Y. Patent Number: US 181,074 Application Filed: July 17, 1876 Date of Patent (Publication/Grant): August…

    View full analysis →added 9/17/2026
  • US185309
    0 cases1/8 sections

    I'll search for authoritative information on this patent number. US Patent 185,309 — Verification Summary Search note: I retrieved the authoritative full text from the Google Patents "en" page for US185309…

    View full analysis →added 9/24/2026
  • US185628
    0 cases1/8 sections

    Patent Overview — US 185,628 Title: Improvement in Combined Handle-Plate and Escutcheon for Doors Patentee: John Collins, of Darlington, township of Hohokus, county of Bergen, New Jersey. Assignee: Hopkins & Dickinson Manufacturing…

    View full analysis →added 9/23/2026
  • US187719
    0 cases1/8 sections

    Patent Overview — US187719A Title: "Improvement in pumps for town and city supply" Inventor: William H. Lang, of Vergennes, Vermont Patent number: US187719A Publication/grant date: February 27, 1877 Application filed: January 18, 1877…

    View full analysis →added 9/21/2026
  • US189679
    0 cases1/8 sections

    Patent Overview — US 189,679 Title: Improvement in Seeding-Machines Patentee: John C. Baker, of Mechanicsburg, Champaign County, Ohio Patent number: US 189,679 Granted: April 17, 1877 Application filed: April 5, 1875 Publication date…

    View full analysis →added 9/23/2026
  • US191088
    0 cases1/8 sections

    Patent Overview — US 191,088 Title: Improvement in Skylight Lifter and Lock Patentee: John F. Wollensak, of Chicago, Cook County, Illinois Dates: Application filed April 23, 1877; patent granted and published May 22, 1877. The source lists…

    View full analysis →added 9/23/2026
  • US206103
    0 cases1/8 sections

    Patent Overview — US 206,103 Title: Improvement in Buttons and Studs Patentee: Carl E. S. Gederen, of Philadelphia, Pennsylvania Patent date: July 16, 1878 Application filed: April 29, 1878 Publication number: US206103A Legal status (as…

    View full analysis →added 9/23/2026
  • US2069960
    0 cases1/8 sections

    Patent Overview — US 2069960 A Title: Apparatus for burning liquid fuel Assignee/Current Assignee (as listed): Universal Oil Burner Co. Inc. (original assignee listed as "Universal Oil Burner Co I") Inventor: Albert A. La Pointe Dates…

    View full analysis →added 9/21/2026
  • US213309
    0 cases1/8 sections

    Patent Overview — US 213,309 Title: Improvement in Pumps Inventor: William O. Wilcox, of San Francisco, California Patent Date: March 18, 1879 Application Filed: December 19, 1877 Publication Number: US213309A Assignee: None identified in…

    View full analysis →added 9/21/2026