The catalog

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.

Demand letter analyzer

You got a patent demand letter. Now what?

Paste the letter — we extract the asserted patents, identify the asserter, characterize their litigation history, flag validity vulnerabilities, and draft a sample response letter your attorney can review. Free, private, ~2-3 minutes.

Analyze a letter →

Analyze a patent

Drop a US patent number — we’ll verify it on Google Patents and generate the full invalidity dossier.

By industry

Software Technology & Computing Systems (T)(1343)Medical (M)(713)High-Tech (T)(550)Wireless Technologies(508)Semiconductor (T)(386)Automotive (A)(298)Industrial Manufacturing (IM)(295)Media & Broadcasting (T)(189)Biotechnology(153)Energy (E)(147)Optical Technology(144)Financial Technology (FT)(132)Sporting Goods (S)(84)Other (O)(73)Audio Technology(66)Consumer Durables(56)Home Appliance (HA)(48)Lighting (L)(47)Footwear(37)Agriculture (AG)(36)Firearms (F)(36)Gaming (G)(36)Food (FD)(35)Railroad(33)Home Security(31)Optical Communication(22)Audience Measurement(19)Plumbing(16)Baby Products(12)Printing Technology(10)Fire Safety (FS)(6)Retail Security(6)Telecommunications(5)Tech (T)(4)Aerospace(3)Aerospace (AS)(3)Printing Technology (P)(3)Aerospace (A)(2)Construction (C)(2)Printing (P)(2)Retail Technology (RT)(2)Telecommunications (T)(2)Telecommunications (TC)(2)Toys(2)Advertising (AD)(1)Aerospace (Ae)(1)Aviation(1)Aviation (AV)(1)Building & Construction(1)Building Construction (BC)(1)Building Materials(1)Chemical (C)(1)Chemical Sensing(1)Cosmetics (C)(1)Data Communication(1)Document Security(1)Electrical Components(1)Environmental Monitoring (EM)(1)Fencing(1)Fire Safety(1)Furniture (F)(1)High-Tech(1)Logistics (L)(1)Logistics & Shipping(1)Marine (M)(1)Maritime Logistics(1)Musical Instruments (MI)(1)Networking (N)(1)Office Equipment(1)Office Equipment (OE)(1)Paints & Coatings(1)Pet Products(1)Printing(1)Printing Technology (PT)(1)Retail Technology(1)Retail Technology (R)(1)Software Technology (T)(1)Textiles(1)Textiles (TX)(1)Tobacco (TB)(1)Vaping (V)(1)Video Surveillance(1)Video Technology(1)Water Treatment(1)
  • US5808894
    0 cases1/8 sections

    Patent Overview — US 5,808,894 Title: Automated ordering method Patent number: US 5,808,894 A Application number: US08/329,725 Inventors: Timothy A. Wiens; Richard A. Burgess Original assignee: Optipat Inc Current assignee (as listed)…

    View full analysis →added 9/24/2026
  • US5809085
    0 cases1/8 sections

    Patent Overview — US 5,809,085 A Title: Apparatus and method for detecting and discriminating various signal types in the presence of impulse distortions Patent number / application: US 5,809,085 A; Application US 08/496,048 Dates…

    View full analysis →added 9/23/2026
  • US5815492
    0 cases1/8 sections

    Patent Overview — US5815492A Title: Dynamic bandwidth estimation and adaptation in high speed packet switching networks Patent number: US5815492A Application number: US08/807,499 Filing date: 1997-02-27 Priority date: 1996-06-20…

    View full analysis →added 9/23/2026
  • US5818447
    0 cases1/8 sections

    Patent Overview — US 5,818,447 Title: System and method for in-place editing of an electronic mail message using a separate program Patent number: US5818447A Application number: US08/660,019 Inventors: Richard J. Wolf; Srinivasa R…

    View full analysis →added 9/23/2026
  • US5819184
    0 cases1/8 sections

    Patent Overview — US 5,819,184 Title: "Portable communications and data terminal operating to optimize receipt of both incoming CDPD and AMPS messages" Patent number / application: US 5,819,184 A; Application US 08/496,282, filed…

    View full analysis →added 9/23/2026
  • US5820062
    0 cases1/8 sections

    Patent Overview — US 5,820,062 A Title: Winding machine Inventor: Carlo Menegatto Assignee: Menegatto S.R.L. (original and current) Application No.: US 08/859,700 Filing date: 1997-05-21 Priority date: 1996-05-24 Publication/grant date…

    View full analysis →added 9/23/2026
  • US5821887
    0 cases1/8 sections

    Patent Overview — US 5821887 A Title: Method and apparatus for decoding variable length codes Patent number: US 5,821,887 A Application number: US 08/747,980 Inventor: Chunrong Zhu Assignee: Intel Corporation (original and current assignee…

    View full analysis →added 9/23/2026
  • US5825419
    0 cases1/8 sections

    Patent Overview: US 5,825,419 A Title: Coding device and decoding device of digital image signal Assignee: Mitsubishi Electric Corp (original assignee per the supplied record) Key dates: Priority date 1995-09-29; application number…

    View full analysis →added 9/23/2026
  • US5825891
    0 cases1/8 sections

    Patent Overview: US5825891A — "Key Management for Network Communication" Title: Key management for network communication Patent number: US5825891A Application number: US08/959,919 Inventors: Roger H. Levesque; Jeffrey A. Kraemer; Ashok P…

    View full analysis →added 9/21/2026
  • US5826014
    0 cases1/8 sections

    Patent Overview: US5826014A Title: Firewall system for protecting network elements connected to a public network Patent number: US5826014A (application US08/595,957) Inventors: Christopher D. Coley; Ralph E. Wesinger, Jr. Original…

    View full analysis →added 9/21/2026
  • US5828322
    0 cases1/8 sections

    Patent Overview: US 5,828,322 A Title: System for controlling delivery and return of printed matter Patent number: US 5,828,322 A Application number: US 08/644,662 Inventor: Hans Joachim Eberhard Assignee: Individual (original and current…

    View full analysis →added 9/24/2026
  • US5828488
    0 cases1/8 sections

    US 5,828,488 A — Reflective Polarizer Display Title: Reflective polarizer display Patent number: US5828488A Application number: US08/402,349 Assignee/current assignee: Minnesota Mining and Manufacturing Co (original); 3M Innovative…

    View full analysis →added 9/23/2026
  • US5831089
    0 cases1/8 sections

    Patent Overview: US5831089A Title: Process to produce midazolam Patent number: US5831089A Application number: US08/864,043 Inventor: Joel E. Huber Original/current assignee: Pharmacia and Upjohn Co Priority date: 1996-07-01 Filing date…

    View full analysis →added 9/23/2026
  • US5832218
    0 cases1/8 sections

    Patent Overview — US 5,832,218 Title: Client/server electronic mail system for providing off-line client utilization and seamless server resynchronization (as rendered in the supplied source, including the "providng" typographical…

    View full analysis →added 9/24/2026
  • US5832503
    0 cases1/8 sections

    Patent Overview — US 5,832,503 A Title: Method and apparatus for configuration management in communications networks Patent number: US 5,832,503 A (application US08/394,143) Original assignee: Cabletron Systems Inc. (the excerpt also lists…

    View full analysis →added 9/23/2026
  • US5835726
    0 cases1/8 sections

    Patent Overview: US 5,835,726 Title: System for securing the flow of and selectively modifying packets in a computer network Patent number: US 5,835,726 A Application number: US 08/664,839 Assignee: Check Point Software Technologies Ltd…

    View full analysis →added 9/23/2026
  • US5835727
    0 cases1/8 sections

    Patent Overview: US 5,835,727 Title: Method and apparatus for controlling access to services within a computer network Patent number: US5835727A | Application: US08/762,393 | Inventors: Thomas K. Wong; Sanjay R. Radia; Swee Boon Lim…

    View full analysis →added 9/24/2026
  • US5835785
    0 cases1/8 sections

    Patent Overview — US 5,835,785 A Title: Multiplexed three line synchronous/full-duplex asynchronous data bus and method therefor Patent number / application: US 5,835,785 A; Application US08/338,993 Inventors: Eric J. Overtoom; Manohar A…

    View full analysis →added 9/23/2026
  • US5838403
    0 cases1/8 sections

    Patent Overview — US 5,838,403 A Title: "Liquid crystal display system with internally reflecting waveguide for backlighting and non-Lambertian diffusing" Patent number / application: US 5,838,403 A (application US 08/601,133) Original…

    View full analysis →added 9/23/2026
  • US5844586
    0 cases1/8 sections

    Patent Overview — US 5,844,586 A Title: "Process for making ink jet heater chips" Patent number / application: US 5,844,586 A; Application No. US 08/628,059. Inventors: Karen L. Berry and Joseph P. Maniaci. Assignee: Originally assigned to…

    View full analysis →added 9/23/2026