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)

US5515379
0 cases1/8 sections
Patent Overview — US5515379A Title: Time slot allocation method Patent number: US5515379A | Application: US08/137,541 | Inventors: Kenneth J. Crisler, Michael L. Needham | Original assignee: Motorola, Inc. | Current assignee (as listed)…
View full analysis →added 9/21/2026
US5518139
0 cases1/8 sections
US Patent 5,518,139 — Summary Bibliographic Data (verified against Google Patents, EveryPatent, FreePatentsOnline, and USPTO.report) | Field | Value | |---|---| | Patent number | US5518139A (U.S. Patent 5,518,139) | | Title | Portable…
View full analysis →added 8/27/2026
US5519695
0 cases1/8 sections
Patent Overview — US 5,519,695 A ("Switch element for fiber channel networks") Bibliographic data (from source): Application US08/330,155; filed 1994-10-27; priority 1994-10-27; granted/published 1996-05-21. Inventors: Robin Purohit, Bent…
View full analysis →added 9/23/2026
US5525917
0 cases1/8 sections
Patent Overview — US5525917A Title: Sense amplifier with feedback and stabilization Patent number: US5525917A Application number: US08/358,210 Inventors: Myron W. Wong, Dirk A. Reese, John C. Costello Assignee: Altera Corp (original…
View full analysis →added 9/21/2026
US5528584
0 cases1/8 sections
Patent Overview — US 5,528,584 A Title: High performance path allocation system and method with fairness insurance mechanism for a fiber optic switch. Assignee/Inventor data (from supplied record): Original assignee Hewlett Packard Co…
View full analysis →added 9/23/2026
US5530235
0 cases1/8 sections
Patent Overview: US5530235A Title: Interactive contents revealing storage device Patent number: US5530235A Application number: US08/389,670 Filing date / Priority date: 1995-02-16 Publication (grant) date: 1996-06-25 Original assignee…
View full analysis →added 9/23/2026
US5530626
0 cases1/8 sections
Patent Overview: US 5,530,626 A Title: Athletic shoe and articles of clothing with replaceable unitary assembly for generating and broadcasting an audible signal Patent number: US 5,530,626 A Application number: US 08/304,496 Inventor…
View full analysis →added 9/23/2026
US5533019
0 cases1/8 sections
Patent Overview — US 5,533,019 A Title: "Packet data in an analog cellular radiotelephone system" Assignee / Inventor: Original assignee Motorola, Inc.; inventor Jay P. Jayapalan (recorded as "JAYAPALAN, JAY PURUSHOTHAMAN"). The listing…
View full analysis →added 9/23/2026
US5535035
0 cases1/8 sections
US5535035A — Patent Overview Title: Optical fiber ring communications system and communications method Patent number: US5535035A Application number: US08/306,560 Inventors: Steven M. DeFoster; Horst L. Truestedt; Raymond J. Thatcher…
View full analysis →added 9/23/2026
US5537410
0 cases1/8 sections
Patent Overview — US 5,537,410 Title: Subsequent frame variable data rate indication method Patent number: US 5,537,410 A Application number: US 08/306,777 Inventor: Kaiping Li Original assignee: Oki Telecom Inc. Current assignee (as…
View full analysis →added 9/21/2026
US5544222
0 cases1/8 sections
Patent Overview — US5544222A Title (as listed): "Cellular digtial packet data mobile data base station" (spelling as given in the source). Patent number / application: US5544222A; application US08/152,005, filed 1993-11-12; granted and…
View full analysis →added 9/23/2026
US5544321
0 cases1/8 sections
Patent Overview: US5544321A Title: System for granting ownership of device by user based on requested level of ownership, present state of the device, and the context of the device Patent number: US5544321A | Application number…
View full analysis →added 9/23/2026
US5546196
0 cases1/8 sections
Patent Overview — US 5,546,196 A Title: Supplemental photofinishing data system Patent number: US 5,546,196 A Application number: US 08/394,531 Inventors: Robert D. Huot; John J. Acello Original assignee: Eastman Kodak Company Current…
View full analysis →added 9/24/2026
US5550676
0 cases1/8 sections
US5550676A — Surface Light Source Element: Overview Title: Surface light source element Patent number: US5550676A Application number: US08/300,518 Inventors: Makoto Ohe; Issei Chiba Original assignee: Mitsubishi Rayon Co Ltd (listed…
View full analysis →added 9/23/2026
US5550984
0 cases1/8 sections
Patent Overview: US 5,550,984 A Title: Security system for preventing unauthorized communications between networks by translating communications received in IP protocol to non-IP protocol to remove address and routing services information…
View full analysis →added 9/21/2026
US5554982
0 cases1/8 sections
Patent Overview — US5554982A Title: Wireless train proximity alert system Patent number: US5554982A | Application: US08/283,460 | Inventors: Keith L. Shirkey, Bruce A. Casella Assignee: Original assignee Hughes Aircraft Co; current…
View full analysis →added 9/23/2026
US5555416
0 cases1/8 sections
Patent Overview — US 5,555,416 A Title: Automated software installation and operating environment configuration for a computer system based on classification rules Assignee: Sun Microsystems Inc. (original and current assignee as listed)…
View full analysis →added 9/24/2026
US5556940
0 cases1/8 sections
US5556940A — Patent Overview Title: Parathyroid hormone analogues for the treatment of osteoporosis Patent number: US5556940A Application number: US08/262,495 Assignee: National Research Council of Canada Inventors: Gordon E. Willick…
View full analysis →added 9/23/2026
US5557088
0 cases1/8 sections
Patent Overview — US5557088A Title: Self-scanning POS system, self-scanning registration terminal, control apparatus for self-scanning registration terminal and POS apparatus for self-scanning registration terminal. Assignee: Fujitsu Ltd…
View full analysis →added 9/24/2026
US5557209
0 cases1/8 sections
Patent Overview — US 5,557,209 Title: Identification of pin-open faults by capacitive coupling through the integrated circuit package Patent number: US 5,557,209 A Application number: US 08/400,787 Inventor(s): David T. Crook; Kevin W…
View full analysis →added 9/23/2026