US 5852810

Here's a concise summary of US Patent 5852810:

US Patent 5852810: Geographic specific information search system and method

• Title: Geographic specific information search system and method
• Assignee: STUDENT HOUSING NETWORK Inc FORMERLY KNOWN AS SH NETWORK Inc (Current Assignee); Student Housing Network (Original Assignee)
• Inventors: James P. Sotiroff, Gerald W. Walden
• Filing Date: January 29, 1996
• Issue Date: December 22, 1998
• Abstract: The patent describes a geographic-specific information search system and method that uses a World Wide Web home page and associated script files to search for housing information in a specified geographic region. Users can narrow their search to a desired geographic area by interacting with graphical maps. The system accepts query criteria, searches a database of property listings, and displays a map of the desired region with highlighted points of interest corresponding to properties that meet the search criteria. Users can then select these properties on the map to view detailed information about them.
• Legal Status: Expired - Fee Related (Anticipated expiration date: January 29, 2016).

Plain-Language Overview of Independent Claims:

• Independent Claim 1 (Method): This claim describes a method for a user to find, view, and save geographic-specific housing information. It involves:

  • Displaying a broad graphical map with smaller selectable regions.
  • Allowing the user to progressively zoom in on the map by selecting regions, ultimately reaching a desired geographic area.
  • Showing specific housing locations ("highlighted points of interest") on the detailed map.
  • Retrieving detailed information from a database about any selected housing location.
  • Enabling the user to create a list of interesting properties and submit their contact information to connect with property managers.

• Independent Claim 10 (System): This claim describes a computer system designed to perform the geographic information search. Key components include:

  • A database holding real estate listing data, including property locations defined by map coordinates.
  • Map tables containing various map images and coordinates of predefined features on those maps.
  • An input/output interface for communication over a computer network (like the World Wide Web) to display maps and listings, and receive user queries (e.g., coordinate selections from a pointing device).
  • A query handler that interprets user input coordinates using the map tables to identify a map, and processes user-entered search criteria to retrieve relevant property records from the database.
  • A map compiler that creates a custom map for the user's query, placing the found properties at their correct locations within the map boundaries.
  • A table builder that creates a new map table specific to the query, containing pointers to the found properties and their coordinates on the custom map, which then augments the main set of map tables.
  • This setup allows users to select properties on the custom map using a pointing device, which the system then decodes to display detailed listing data.

• Independent Claim 22 (Method): This claim outlines a method for conducting a search of geographic-specific housing information. It entails:

  • Presenting an initial graphical map.
  • Defining a first search query based on a specific geographic region by interactively narrowing down displayed map subregions.
  • Defining a second search query using real estate listing criteria (e.g., number of bedrooms, price range).
  • Searching a database for properties that satisfy both the geographic and property criteria.
  • Generating and displaying a graphical map of the desired geographic area, with the found properties highlighted at their respective locations.
  • Allowing the user to select these highlighted property features.
  • Displaying detailed housing information for the selected properties.

CAFC 2026 Dockets:
A search of the U.S. Court of Appeals for the Federal Circuit (CAFC) 2026 dockets for patent number US5852810 did not yield specific results indicating any scheduled cases directly involving this patent for April, May, or June 2026, based on the provided search snippets.

As a patent attorney, I have investigated known litigation involving US Patent 5852810.

A search for litigation directly involving US Patent 5852810 across various databases, including Unified Patents and PACER, did not yield any specific case results for this patent number.

It is important to note that while PACER is a valuable resource for federal court records, a recent class-action lawsuit alleged that the U.S. government unlawfully overcharged users for PACER fees between April 21, 2010, and May 31, 2018. This class action, National Veterans Legal Services Program, et al. v. United States, Case No. 1:16-CV-00745-PLF, in the District Court for the District of Columbia, resulted in a $125 million settlement, with final approval granted on March 20, 2024. An appeal of this final approval was filed on April 17, 2024, to the United States Court of Appeals for the Federal Circuit, which heard oral argument on January 7, 2026. This PACER litigation is a general issue with the system and not specific to US Patent 5852810.

Based on the available information, there is no known litigation specifically involving US Patent 5852810.

Proceedings overview

There is no PTAB activity on file for US Patent 5852810. This indicates that the patent has not been subjected to any inter partes review (IPR), post-grant review (PGR), or covered business method (CBM) patent proceedings at the USPTO.

Strategic summary

As of today, 2026-05-16, all claims of US Patent 5852810 remain untested by any AIA trial proceeding before the PTAB. This means there are no claims that have been canceled or sustained in such proceedings. The patent expired on 2016-01-29 due to fee-related issues.

The absence of PTAB proceedings suggests a few possibilities:

• The patent may not have been asserted aggressively in litigation, thus not prompting challenges.
• The claims might be considered sufficiently robust against common prior art challenges under AIA standards, or potential challengers did not find it economically viable to pursue PTAB trials, particularly given the patent's expired status.
• The patent's focus on "geographic specific housing information" and its filing date in 1996 might place it in a technological area where earlier art was less comprehensively digitized or accessible for IPR challenges, or the specific features claimed were not easily challenged under the Alice/Mayo framework for patent eligibility (though the patent predates much of this jurisprudence's impact on CBMs and PGRs).

There is no estoppel landscape to consider as no PTAB trials have occurred.

Recommended next steps

If you are a defendant facing assertion of US Patent 5852810, the absence of PTAB activity means that all claims are currently considered valid as issued by the USPTO, without any re-examination or challenge in an AIA trial. Therefore, any prior-art grounds against this patent remain available for assertion in district court litigation or other venues, subject to the usual procedural rules and statutory bars (e.g., 35 U.S.C. § 102, 103).

Given the patent's expired status (2016-01-29), any potential infringement would be limited to activities occurring before that date. This significantly limits the scope of damages in any new litigation.

Inventors

• James P. Sotiroff: Employer not determinable from the patent document.
• Gerald W. Walden: Employer not determinable from the patent document.

Original assignee

The original assignee was Student Housing Network. Based on the patent title and abstract, their primary line of business appears to be providing a system and method for listing and locating housing, specifically tailored for geographic-specific searches, like student housing. Their current status is "STUDENT HOUSING NETWORK Inc FORMERLY KNOWN AS SH NETWORK Inc" as the current assignee, which implies they are still operating, potentially under a changed name or corporate structure.

Assignment timeline

• 1996-01-29 (executed) / recorded 1996-01-29 — Reel 007693/0942
  • Conveyance: Assignment
  • Assignor: James P. Sotiroff, Gerald W. Walden
  • Assignee: Student Housing Network
  • Correspondent: Price, Heneveld, Cooper, De Witt & Litton (Grand Rapids, MI).
  • Context: Original assignment from inventors to the initial assignee.
• 1999-05-27 (executed) / recorded 1999-05-27 — Reel 010074/0616
  • Conveyance: Assignment
  • Assignor: SHN, L.L.C. FORMERLY KNOWN AS STUDENT HOUSING NETWORK, L.L.C.
  • Assignee: STUDENT HOUSING NETWORK, INC., FORMERLY KNOWN AS S.H. NETWORK, INC.
  • Correspondent: Howard & Howard Attorneys, P.C. (Kalamazoo, MI).
  • Context: Internal reorganization / change of name.
• 1999-05-27 (executed) / recorded 1999-05-27 — Reel 010074/0617
  • Conveyance: Assignment
  • Assignor: STUDENT HOUSING NETWORK
  • Assignee: STUDENT HOUSING NETWORK, INC., FORMERLY KNOWN AS S.H. NETWORK, INC.
  • Correspondent: Howard & Howard Attorneys, P.C. (Kalamazoo, MI). This correspondent also appeared on reel 010074/0616.
  • Context: Internal reorganization / change of name.

Timeline diagram

timeline
    title Ownership of US 5852810
    1996 : Assigned to Student Housing Network
    1998 : Issued
    1999 : Assigned to Student Housing Network Inc (reorg)
         : Assigned to Student Housing Network Inc (reorg)
    2016 : Patent expired

NPE / troll-pattern signals

1. Shell-entity transfer — Not present. The assignments recorded appear to be internal reorganizations or name changes of the original operating company, "Student Housing Network" to "Student Housing Network, Inc." or "SHN, L.L.C.". There is no indication of transfer to an entity with typical shell-entity naming conventions (e.g., "IP," "Licensing") or a registered-agent address as the primary place of business.

2. Known asserter in the chain — Not present. None of the assignees (Student Housing Network, SHN, L.L.C., or STUDENT HOUSING NETWORK, INC.) are recognized on common NPE lists.

3. Repeat correspondent across the chain — Present. Howard & Howard Attorneys, P.C. (Kalamazoo, MI) appears as the correspondent for two consecutive assignments on reels 010074/0616 and 010074/0617, both executed and recorded on 1999-05-27.

4. Cascading transfers — Present. There are two consecutive assignments recorded on the same date (1999-05-27) to the same assignee, related to a change of name/reorganization, as indicated by reels 010074/0616 and 010074/0617. While not a typical NPE cascading transfer to different entities, it shows multiple transfers in a short period.

5. Pre-litigation transfer — Not present. There is no indication of any litigation associated with this patent.

6. Bankruptcy fire-sale — Not present. There is no information to suggest the original assignee or any subsequent assignee went through bankruptcy proceedings that resulted in the sale of this patent.

7. Privateering — Unclear. There is no information available from the assignment records or the patent itself to suggest privateering activity.

8. Defensive aggregator (anti-NPE) — Not present. The chain does not terminate at any known defensive aggregators.

Verdict

Insufficient data. While there are instances of repeat correspondents and cascading transfers related to internal corporate reorganization (Reel 010074/0616 and 010074/0617), there is no evidence of transfer to a shell entity or a known patent asserter. Therefore, based solely on the assignment records, there is insufficient data to definitively label this patent as being involved in NPE activity.

USPTO Assignment Center search page: https://assignmentcenter.uspto.gov/patent/index.html

To identify the most relevant prior art for US Patent 5852810, I will search the USPTO database for the patent and then review its cited references. I will specifically look for the "Cited by Examiner" section, as these are typically considered the most pertinent prior art by the patent office.

According to the USPTO website, the "Patent Public Search" tool is a web-based search application for patents and patent application publications that provides enhanced access to prior art.

USPTO Search for Patent 5852810

The patent text provided already includes a "Citations" section, which lists prior art cited by the examiner. I will use this section to extract the relevant information.

Most Relevant Prior Art for US Patent 5852810

Here's an analysis of the prior art cited in US Patent 5852810, focusing on those marked as "Cited by examiner":

1. US4870576A

   • Full Citation: US4870576A - Real estate search and location system and method.
   • Publication Date: September 26, 1989.
   • Priority Date: March 19, 1986.
   • Assignee: Realpro, Ltd.
   • Brief Description: This patent describes a real estate search and location system and method. While the full text isn't provided here, the title suggests a system for finding real estate, which is broadly related to US5852810's objective of locating housing.
   • Potential Anticipation (35 U.S.C. § 102): Potentially anticipates elements of claims 1, 10, and 22, specifically concerning a "search system and method" for "real estate" or "housing information." The extent of anticipation would depend on whether US4870576A discloses the specific interactive graphical map features and recursive narrowing of geographic areas as claimed in US5852810.

2. US5032989A

   • Full Citation: US5032989A - Real estate search and location system and method.
   • Publication Date: July 16, 1991.
   • Priority Date: March 19, 1986.
   • Assignee: Realpro, Ltd.
   • Brief Description: Similar to US4870576A, this patent also describes a real estate search and location system and method, likely being a continuation or related patent from the same assignee.
   • Potential Anticipation (35 U.S.C. § 102): Similar to US4870576A, it potentially anticipates aspects of claims 1, 10, and 22, depending on the level of detail regarding graphical map interaction and geographic search refinement.

3. US5179652A

   • Full Citation: US5179652A - Method and apparatus for storing, transmitting and retrieving graphical and tabular data.
   • Publication Date: January 12, 1993.
   • Priority Date: December 13, 1989.
   • Assignee: Anthony I. Rozmanith.
   • Brief Description: This patent focuses on handling graphical and tabular data, which is relevant to US5852810's use of graphical maps and database information.
   • Potential Anticipation (35 U.S.C. § 102): Could potentially anticipate aspects of claims 1 and 10 related to "presenting a graphical map" and "storing a plurality of database records of real estate listing data," particularly concerning the technical mechanisms for storing, transmitting, and retrieving such data.

4. US5185857A

   • Full Citation: US5185857A - Method and apparatus for multi-optional processing, storing, transmitting and retrieving graphical and tabular data in a mobile transportation distributable and/or networkable communications and/or data processing system.
   • Publication Date: February 9, 1993.
   • Priority Date: December 13, 1989.
   • Assignee: Rozmanith A Martin.
   • Brief Description: This patent describes a system for processing, storing, transmitting, and retrieving graphical and tabular data, emphasizing multi-optional processing and networkability. This is highly relevant given US5852810's reliance on a networked system (World Wide Web) and database.
   • Potential Anticipation (35 U.S.C. § 102): Strong potential to anticipate aspects of claims 1, 10, and 22, particularly regarding the underlying data handling, networking, and user interaction with graphical data in a system. The "multi-optional processing" might relate to various search criteria or display options.

5. US5283731A

   • Full Citation: US5283731A - Computer-based classified ad system and method.
   • Publication Date: February 1, 1994.
   • Priority Date: January 19, 1992.
   • Assignee: Ec Corporation.
   • Brief Description: This patent describes a computer-based system for classified advertisements. This directly relates to the concept of listing and searching for housing information, which is a core function of US5852810.
   • Potential Anticipation (35 U.S.C. § 102): Could potentially anticipate the broader concept of a system for listing and searching information (e.g., housing), as covered in claims 1, 10, and 22. The specific method of "geographic specific" searching via interactive maps would need to be compared in detail.

6. US5325297A

   • Full Citation: US5325297A - Computer implemented method and system for storing and retrieving textual data and compressed image data.
   • Publication Date: June 28, 1994.
   • Priority Date: June 25, 1992.
   • Assignee: System Of Multiple-Colored Images For Internationally Listed Estates, Inc.
   • Brief Description: This patent describes a computer-implemented method for storing and retrieving textual and compressed image data, particularly for listed estates. This is highly relevant to US5852810's database storage of property information, including digitized pictures and video.
   • Potential Anticipation (35 U.S.C. § 102): High potential to anticipate aspects of claims 1, 5, 6, 10, and 22 regarding the storage and retrieval of property listing data, including graphical elements (digitized pictures and video clips). The "internationally listed estates" aspect suggests a broad geographic scope.

7. US5335323A

   • Full Citation: US5335323A - Computer human interface with multiapplication display.
   • Publication Date: August 2, 1994.
   • Priority Date: January 5, 1987.
   • Assignee: Motorola, Inc.
   • Brief Description: This patent focuses on a computer-human interface with multi-application display capabilities. While general, a sophisticated user interface is critical to US5852810's interactive map system.
   • Potential Anticipation (35 U.S.C. § 102): Could anticipate general aspects of user interface design and display of information, as mentioned in claims 1, 10, and 22, but likely not the specific geographic search and map interaction features.

8. US5371845A

   • Full Citation: US5371845A - Technique for providing improved user feedback in an interactive drawing system.
   • Publication Date: December 6, 1994.
   • Priority Date: April 27, 1990.
   • Assignee: Ashlar, Inc.
   • Brief Description: This patent describes a technique for improved user feedback in an interactive drawing system. The interactive nature of US5852810's graphical maps suggests some overlap in principles.
   • Potential Anticipation (35 U.S.C. § 102): Might anticipate general concepts of "interactive graphical maps" or user feedback mechanisms, as mentioned in claims 1, 10, and 22, but likely not the specific application to geographic-specific information searching for housing.

9. US5532838A

   • Full Citation: US5532838A - Method & apparatus for dynamically creating and transmitting documents via facsimile equipment.
   • Publication Date: July 2, 1996.
   • Priority Date: December 27, 1993.
   • Assignee: Barbari; Edward P.
   • Brief Description: This patent describes a method and apparatus for dynamically creating and transmitting documents via facsimile equipment. While it deals with document transmission, it's less directly related to the core geographic search and display of housing information than other references.
   • Potential Anticipation (35 U.S.C. § 102): Unlikely to directly anticipate core claims of US5852810, as the focus is on fax transmission rather than interactive geographic search. It might be cited for broader concepts of dynamic document generation or transmission, which are peripheral to the invention.

10. US5664115A

    • Full Citation: US5664115A - Interactive computer system to match buyers and sellers of real estate, businesses and other property using the internet.
    • Publication Date: September 2, 1997.
    • Priority Date: June 7, 1995.
    • Assignee: Fraser; Richard.
    • Brief Description: This patent describes an interactive computer system for matching buyers and sellers of real estate and other properties using the Internet. This is highly relevant, as it describes a system for real estate transactions over the Internet, which is the underlying domain of US5852810.
    • Potential Anticipation (35 U.S.C. § 102): High potential to anticipate aspects of claims 1, 10, and 22, particularly concerning the use of the Internet for real estate listings and matching users with properties. The key distinction for US5852810 would lie in the specific interactive graphical map interface and recursive geographic narrowing.

11. US5721851A

    • Full Citation: US5721851A - Transient link indicators in image maps.
    • Publication Date: February 24, 1998.
    • Priority Date: July 31, 1995.
    • Assignee: International Business Machines Corporation.
    • Brief Description: This patent describes transient link indicators in image maps. US5852810 explicitly uses "image maps" for user interaction and selection of geographic areas.
    • Potential Anticipation (35 U.S.C. § 102): Strong potential to anticipate aspects of claims 1, 10, and 22 related to the use of "graphical maps" and "image maps" for user selection and interaction. This reference could anticipate the technical implementation of how selectable regions on a map are handled, which is a fundamental part of US5852810's user interface.

Obviousness Analysis of US Patent 5852810 Under 35 U.S.C. § 103

This analysis examines the obviousness of US Patent 5852810, "Geographic specific information search system and method," under 35 U.S.C. § 103. The analysis will consider the patent's independent claims (Claims 1, 10, and 22) in light of prior art available before the patent's priority date of January 29, 1996.

A person having ordinary skill in the art (PHOSITA) at the time of the invention would have possessed knowledge of foundational internet technologies (e.g., HTTP, HTML, CGI), database management (e.g., SQL), and graphical user interface design. They would also have been aware of the growing need for efficient online systems for real estate search and property management.

Combination of Prior Art References: US5664115A and US5721851A

The primary combination of prior art references that would render the independent claims of US5852810 obvious is US5664115A (Fraser) and US5721851A (IBM).

• US5664115A (Priority Date: June 7, 1995): This patent describes an "Interactive computer system to match buyers and sellers of real estate, businesses and other property using the internet." Fraser discloses an internet-based system where property owners or agents can list properties, and potential buyers or renters can search through listings in a database. The system allows for searching by various criteria, including geographic location (e.g., state) and property attributes such as price range, property type, number of bedrooms, and bathrooms. It enables users to view properties that fit their needs and implies a mechanism for matching interested parties.

• US5721851A (Priority Date: July 31, 1995): This patent discloses "Transient link indicators in image maps." It describes the use of image maps on a computer display, where regions of an image can be selected by a pointing device to activate associated links or retrieve information.

Motivation to Combine US5664115A and US5721851A

A PHOSITA, seeking to enhance the user experience and effectiveness of an internet-based real estate search system (as taught by Fraser, US5664115A), would have been motivated to integrate the interactive graphical map technology described by IBM (US5721851A). While Fraser teaches searching by geographic area (e.g., state), it does not detail a highly visual, interactive map-based method for narrowing that geographic scope. The burgeoning World Wide Web environment in 1996 increasingly emphasized graphical interfaces and intuitive "point-and-click" interactions.

Therefore, it would have been obvious for a PHOSITA to combine Fraser's online real estate search functionality with IBM's image map technology. This combination would allow users of an internet-based real estate system to visually select geographic regions on a map, providing a more engaging and user-friendly way to refine their search location compared to text-based input. Furthermore, once properties meeting the search criteria were identified, displaying them directly on an interactive map, where each property is a clickable "point of interest" (leveraging the image map's linking capability), would be an obvious and desirable improvement for visualizing property locations relative to landmarks and other properties.

Obviousness of Independent Claims

Claim 1: Method of presenting, searching, selecting and maintaining geographic specific housing information

Claim 1 describes a method involving:

• Presenting a graphical map and narrowing the geographic area by recursively selecting smaller regions using a graphical tree structure: Fraser (US5664115A) teaches searching for real estate by geographic location (e.g., state). IBM (US5721851A) teaches displaying an image map where users can select specific regions with a pointing device to retrieve associated information or activate links. A PHOSITA, aiming to improve the geographic search in Fraser's system, would find it obvious to use interactive image maps (IBM) to represent different geographic levels (ee.g., starting with a high-level map, then recursively displaying more detailed maps upon user selection). This hierarchical navigation implicitly forms a "graphical tree structure" for narrowing the search.
• Displaying a desired geographic region with individual highlighted points of interest corresponding to available housing: Fraser describes retrieving "available housing" listings based on search criteria. Once a geographic area is defined using the interactive maps (from the combination), a PHOSITA would find it obvious to visually represent these retrieved properties as "highlighted points of interest" on the displayed map, a natural extension of combining property data with a graphical map interface.
• Recursively selecting highlighted points of interest and retrieving from the database information related to each selected point of interest: IBM teaches selecting points on an image map to retrieve associated information. Fraser teaches storing and retrieving detailed property information from a database. Therefore, the ability to select a highlighted property on the map (using IBM's image map functionality) and retrieve its specific details from Fraser's database would be an obvious integration.
• Compiling an interest list of interesting properties and user information for contacting interested persons: Fraser's system aims to "match buyers and sellers" and enables users to view properties fitting their needs. The creation of an "interest list" (a common feature in online catalogs and search systems for saving items) and collecting user information to facilitate contact with property managers are obvious steps for enabling the "matching" purpose described in Fraser.

Claim 10: Geographic-specific information search system

Claim 10 describes a system including:

• A database for storing real estate listing data with property locations as map coordinates: Fraser's system includes a database for property listings. Storing property locations with coordinates is standard practice for any system intending to display locations on a map.
• A set of map tables identifying map images, geographic boundaries, and coordinate data: Such map tables are fundamental to any geographical information system or interactive map display, as described by IBM (image maps).
• An input/output interface for network communication, displaying maps/listing data, and receiving user queries including input coordinates from a pointing device: Fraser details an internet-based system with a user interface. IBM teaches using a pointing device to enter coordinates on an image map for selection. The combination directly supports this functionality.
• A query handler for decoding input coordinates and accessing map tables and a database to retrieve records that satisfy user queries: Fraser's system includes a query handling mechanism for searching the property database. Integrating the decoding of image map coordinates (from IBM) to dynamically refine the geographic component of the query is a straightforward design choice for a PHOSITA.
• A map compiler for constructing a query-specific map by placing query-specific properties (from retrieved database records) at defined coordinates within the map boundary: Given properties with coordinate data (Fraser) and the capability to display interactive maps (IBM), it would be obvious to generate a map that plots the locations of the retrieved properties. The "map compiler" refers to the known process of overlaying points of interest on a base map.
• A table builder for building a query-specific map table and adding it to the set of map tables: This represents the conventional data management aspect of dynamically generated interactive maps, a routine task for a PHOSITA.
• Whereby the user may view selected real estate listing data by selecting from said query-specific map one of said query-specific properties using a pointing device to enter coordinates for decoding by said query handler: This "whereby" clause describes the user interaction of clicking on a property on the map to view its details, which is the direct combination of IBM's interactive image map selection and Fraser's retrieval of property listing data.

Claim 22: Method of conducting a search of a database of geographic-specific housing information

Claim 22 outlines a method involving:

• Displaying a graphical representation of an initial geographic region and defining a first query by recursively selecting and displaying geographic subregions using a graphical tree structure: This is rendered obvious by the combination of Fraser's geographic search capabilities and IBM's interactive image map technology, as explained for Claim 1. The recursive selection on maps to narrow a geographic area is an obvious application of image maps in a hierarchical context.
• Defining a second query including real estate listing information to form a desired property criteria: Fraser explicitly teaches "searching for listings by state, price, property type, number of bedrooms, bathrooms, and other features," which directly covers this step.
• Searching the database for properties which meet said first and second queries: Fraser teaches searching a database for properties meeting criteria. Combining geographic criteria (first query) with property criteria (second query) into a single database search is a fundamental function of any advanced search system and would be obvious.
• Creating and displaying a query-specific graphical representation of said desired geographic search area having features corresponding to properties found during said database search, displayed at their locations: As explained for Claim 10, given the ability to retrieve properties with location data (Fraser) and display interactive maps (IBM), visually plotting these properties on the relevant map is an obvious enhancement.
• Selecting features from said query-specific graphical representation and displaying geographic-specific housing information describing properties represented by said selected features: This interaction—clicking on a map feature (IBM) to reveal associated property details (Fraser)—is directly derivable from the combination of the two prior art references.

Other Claims Dependent on Independent Claims:

• Claims 2, 3, 4, 18, 19 (Adding, Editing, Deleting Listings): Fraser's system allows "property owner or real estate agent to list property for sale or rent." The ability to add, edit, and delete listings is an inherent, fundamental requirement for maintaining any property listing database and would be obvious to implement in an online system.
• Claims 5, 6, 20, 21 (Displaying digitized pictures/video): While not directly mentioned in Fraser, US5325297A teaches "Computer implemented method and system for storing and retrieving textual data and compressed image data." Given this, and the increasing multimedia capabilities of the internet by 1996, a PHOSITA would find it obvious to include digitized pictures and full-motion video clips in property listings, especially for a system designed to "show" available housing.
• Claims 7, 9, 17, 23 (Notifying property managers, e-mail): Fraser aims to "match buyers and sellers" and implies communication. Sending notifications via "e-mail" was a well-established and obvious method of communication on the internet by 1996 to facilitate such matching.

In summary, the combination of US5664115A and US5721851A, alongside the general knowledge of a PHOSITA at the time, renders the independent claims of US5852810 obvious. The motivation to combine these references would stem from the desire to create a more intuitive, visually rich, and interactive online real estate search experience.

US Patent 5852810: Further Details

As of April 26, 2026, here are further details regarding US Patent 5852810:

Patent Term Adjustments (PTA)

Patent Term Adjustments (PTA) are additions to the 20-year lifespan of a U.S. patent, intended to compensate for delays caused by the USPTO during the prosecution of a utility or plant patent application. The America Inventors Protection Act of 1999 established PTA, providing day-for-day adjustments for certain USPTO administrative delays. These delays include, for example, the USPTO failing to:

• Issue an office action within 14 months after application filing.
• Respond to a reply or appeal within four months.
• Issue a patent within four months after payment of an issue fee.
• Issue a patent within 36 months from the filing date.

The PTA calculation is performed at the time the patent is issued and is included in the Issue Notification Letter.

Based on the provided information, US Patent 5852810 has an issue date of December 22, 1998, and a filing date of January 29, 1996. PTA provisions were established in 1999 and generally apply to applications filed on or after May 29, 2000. Since US5852810 was filed on January 29, 1996, it predates the effective date for PTA. Therefore, there are no patent term adjustments for US Patent 5852810.

Patent Term Extensions (PTE)

Patent Term Extensions (PTE) are available under the Hatch-Waxman Act (35 U.S.C. § 156) for patents on certain human drugs, food or color additives, medical devices, animal drugs, and veterinary biological products. The purpose of PTE is to restore a portion of the patent term lost while the patent holder awaits premarket government approval from a regulatory agency. The maximum length of a PTE is five years.

US Patent 5852810 relates to a "Geographic specific information search system and method" for housing information. This patent does not fall into the categories of products eligible for PTE (human drugs, food/color additives, medical devices, animal drugs, or veterinary biological products). Therefore, there are no patent term extensions for US Patent 5852810.

Continuation Applications

A continuation application is a second application for the same invention claimed in a prior non-provisional application and is filed before the original application is abandoned, withdrawn, or patented. This allows for new claims to be added or old claims to be further prosecuted. The filing of continuation applications is subject to the co-pending requirements of 35 U.S.C. § 120, meaning each subsequent application cannot be filed after the parent application has issued, expired, or been abandoned.

The provided patent text and Google Patents information for US5852810 does not explicitly list any continuation applications.

Divisional Applications

A divisional application is a type of continuing application that can be filed when a parent application claims two or more independent and distinct inventions, and the USPTO requires the application to be restricted to one of them. The divisional application benefits from the filing date of the original application, provided it complies with the requirements of 35 U.S.C. § 120 and is directed solely to subject matter described and claimed in the original application as filed. A divisional application must be filed before the issuance of the patent on the other application.

The provided patent text and Google Patents information for US5852810 does not explicitly list any divisional applications.

Related Family Members

The term "patent family" refers to a set of patent applications and patents filed in various countries to protect the same invention. The provided Google Patents page for US5852810 lists one "Priority Application" and one "Family Application," both referring back to US08/591,927, which is the application number for US5852810 itself. This indicates that there are no explicitly listed foreign equivalents or other related U.S. applications beyond the initial filing leading to this patent in the provided information.

Projected Expiration Date

The original anticipated expiration date for US Patent 5852810 was January 29, 2016. Since the patent was filed on January 29, 1996, the patent term would ordinarily be 20 years from its filing date, according to the Uruguay Round Agreements Act (effective for applications filed on or after June 7, 1995).

As established above, there are no Patent Term Adjustments (PTA) or Patent Term Extensions (PTE) for this patent.

Therefore, the patent US5852810 expired on January 29, 2016. The legal status listed on Google Patents as "Expired - Fee Related" confirms this.

To begin, I need to retrieve the full text of US Patent 5852810 from the USPTO database to ensure the most accurate and up-to-date information for analysis.The USPTO provides a "Patent Public Search" tool for searching patents and patent application publications. To retrieve the full text of US Patent 5852810, I would use this tool. According to USPTO guidelines, for a utility patent number like 5852810, I should enter the number excluding commas and spaces, and omit leading zeroes, unless the original number has less than 7 digits, in which case I add leading zeros to make it 7 digits. Since 5852810 already has 7 digits, I would enter "5852810" directly.

Assuming successful retrieval of the full patent text (which was provided in the prompt), I will now proceed with generating the "Defensive Disclosure" document based on the specified derivation framework.

Defensive Disclosure Document for US Patent 5852810

Patent Title: Geographic specific information search system and method
Patent Number: US5852810
Filing Date: January 29, 1996
Issue Date: December 22, 1998

This document outlines derivative variations for the core claims of US Patent 5852810, aimed at establishing prior art for potential future incremental improvements by competitors.

Derivative Variations for Independent Claim 1 (Method)

Core Claim 1: A method of presenting, searching, selecting and maintaining geographic specific housing information contained in a database and supplied by various property managers, the method comprising the steps of: presenting a graphical map depicting a large initial geographic area, said graphical map being divided into smaller selectable geographic regions; narrowing said initial geographic area by recursively selecting and successively displaying said smaller geographic regions using a graphical tree structure; displaying a desired geographic region, said desired geographic region including individual highlighted points of interest corresponding to available housing; recursively selecting highlighted points of interest and retrieving from the database information related to each selected point of interest; and compiling an interest list of interesting properties, including a list of interesting properties and user information for contacting a person interested in said interesting properties contained in said list.

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1. Material & Component Substitution (for "graphical map," "database," "pointing device," "user interface")

Derivative 1.1: Vector-Based Geospatial Map and Distributed Ledger Database with Haptic Feedback Interaction

• Enabling Description: Instead of raster image maps, this derivative utilizes a vector-based geospatial data model (e.g., OpenStreetMap data rendered dynamically) to present the initial and recursively narrowed geographic areas. The "database" is replaced by a distributed ledger technology (DLT) or blockchain, where property listings and associated metadata (e.g., availability, price, media links) are stored as immutable transactions across a peer-to-peer network. Property managers use cryptographic keys to add or update their listings, ensuring data integrity and provenance. User interaction for selecting regions and points of interest is enhanced with a haptic feedback pointing device, providing tactile confirmation upon successful selection or hovering over a clickable element. The user interface renders these vector maps in real-time, allowing for smoother zooming and panning, and dynamically adjusts the level of detail based on the zoom level and available bandwidth.
• Mermaid Diagram:

  graph TD
      A[User Device with Haptic Feedback] --> B{Internet / P2P Network}
      B --> C[Vector Map Renderer]
      B --> D[Distributed Ledger Nodes]
      C --> E[Dynamic Vector Map Display]
      D -- Property Data (Immutable Transactions) --> E
      E -- User Selections (Haptic Feedback) --> A
      E -- Highlighted POIs --> F[POI Detail Retrieval from DLT]
      F --> G[Interest List Compilation]
      G --> H[Property Manager Notification (via DLT transaction or secure messaging)]
  

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2. Operational Parameter Expansion (Extreme Scales)

Derivative 1.2: Nanoscale Property Search for Micro-Electromechanical Systems (MEMS) Housing

• Enabling Description: This derivative applies the system to a highly specialized domain: the search and visualization of "housing" for components within Micro-Electromechanical Systems (MEMS) or nanofabrication. The "geographic area" refers to a microscopic substrate or a 3D chip architecture. The "graphical map" displays highly magnified electron microscope images or CAD renderings of the MEMS device, with "points of interest" being specific sites for component placement or available "housing" for nano-bots. Recursive selection would involve zooming into specific layers, gates, or molecular structures. The "database" contains specifications for component dimensions, interface requirements, and environmental tolerances. The "interest list" would be a bill of materials or a placement manifest for a micro-assembly process.
• Mermaid Diagram:

  graph TD
      A[Micro-assembly Engineer] --> B{Electron Microscope / CAD Interface}
      B --> C[Micro-geographic Map Display (MEMS Layout)]
      C -- Recursive Zoom/Select --> D[Highlighted Component "Housing" Sites]
      D --> E[Retrieval of Nano-component Specifications from Database]
      E --> F[Micro-assembly "Interest List" (BOM/Placement Manifest)]
      F --> G[Automated Micro-assembly System]
  

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3. Cross-Domain Application

Derivative 1.3.1: Marine Biology Habitat Mapping and Conservation

• Enabling Description: The system is repurposed for marine biologists to map and search for specific underwater habitats. The "graphical map" displays oceanographic charts, bathymetry data, and satellite imagery of coastal regions. "Smaller selectable geographic regions" could be oceanic zones, coral reefs, or hydrothermal vent fields. "Highlighted points of interest" represent known or predicted locations of specific marine species, endangered habitats, or areas suitable for conservation efforts. The database stores ecological data, species observations, environmental parameters (temperature, salinity), and historical conservation records. The "interest list" would be a list of priority conservation areas or research sites.
• Mermaid Diagram:

  graph TD
      A[Marine Biologist] --> B{Oceanographic Data Interface}
      B --> C[Interactive Ocean Map Display (Bathymetry, Habitats)]
      C -- Recursive Selection (Zones, Reefs) --> D[Highlighted Species Locations / Conservation Areas]
      D --> E[Retrieve Ecological Data from Marine Database]
      E --> F[Conservation Priority List]
      F --> G[Research Vessel / ROV Deployment]
  

Derivative 1.3.2: Agricultural Land Management and Crop Optimization

• Enabling Description: This derivative adapts the system for precision agriculture. The "graphical map" depicts farm fields, divided into sub-regions corresponding to individual plots or soil zones. "Highlighted points of interest" signify areas with specific soil conditions, crop health issues, or optimal planting locations for certain crops. The database contains soil analysis data (pH, nutrient levels), historical yield data, weather patterns, and crop-specific growth requirements. The "interest list" could be a list of fields requiring specific nutrient application, pest control, or a prioritized planting schedule.
• Mermaid Diagram:

  graph TD
      A[Farmer/Agronomist] --> B{Agricultural Sensor Network / Satellite Imagery}
      B --> C[Interactive Farm Map Display (Soil Zones, Crop Health)]
      C -- Recursive Selection (Plots, Rows) --> D[Highlighted Areas for Intervention / Optimization]
      D --> E[Retrieve Soil/Crop Data from Agricultural Database]
      E --> F[Actionable Insight List (e.g., Fertilization Plan)]
      F --> G[Automated Farm Equipment (Tractors, Drones)]
  

Derivative 1.3.3: Urban Planning and Infrastructure Development

• Enabling Description: The system is applied to urban planning, where the "graphical map" represents city layouts, zoning maps, and utility infrastructure. "Smaller selectable geographic regions" are districts, neighborhoods, or blocks. "Highlighted points of interest" could indicate available land for development, areas requiring infrastructure upgrades, or locations of public services. The database includes zoning regulations, property ownership, demographic data, traffic patterns, and infrastructure capacity. The "interest list" would be a project pipeline for urban development or a list of areas for public investment.
• Mermaid Diagram:

  graph TD
      A[Urban Planner] --> B{GIS Data / Public Records Interface}
      B --> C[Interactive City Map Display (Zoning, Infrastructure)]
      C -- Recursive Selection (Districts, Blocks) --> D[Highlighted Development Sites / Infrastructure Needs]
      D --> E[Retrieve Urban Planning Data from Database]
      E --> F[Development Project List]
      F --> G[City Council / Development Agencies]
  

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4. Integration with Emerging Tech

Derivative 1.4: AI-Optimized, IoT-Monitored, Blockchain-Verified Property Search

• Enabling Description: This derivative integrates advanced technologies. AI-driven optimization analyzes user preferences, historical search patterns, and real-time market data to proactively suggest relevant geographic regions and properties. IoT sensors installed in listed properties provide real-time monitoring of occupancy, environmental conditions (temperature, humidity), and maintenance needs, updating the "database" with live status information. Property listings, ownership transfers, and leasing agreements are recorded on a blockchain, providing an immutable and transparent audit trail, verified through smart contracts. The "interest list" is automatically curated by the AI, and notification of property managers is triggered by smart contracts when a user's interest aligns with available property or new IoT data indicates a change in status.
• Mermaid Diagram:

  graph TD
      A[User Device] --> B{Web Interface with AI Recommendation Engine}
      B --> C[Real-time Graphical Map (AI-prioritized POIs)]
      C -- User Interaction --> D[Property Database (IoT Data Integration)]
      D --> E[Blockchain Network (Property Deeds, Lease Contracts)]
      E -- Smart Contract Trigger --> F[Automated Interest List / Property Manager Notification]
      IoT[IoT Sensors in Properties] --> D
      AI[AI Optimization Engine] --> B
  

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5. The "Inverse" or Failure Mode

Derivative 1.5: Disaster Response and Limited-Functionality Emergency Shelter Locator

• Enabling Description: This derivative describes a version of the system designed for failure mode scenarios, specifically disaster response and emergency shelter location. In this mode, the system operates with limited functionality and prioritizes critical information. The "graphical map" focuses on disaster-affected areas, displaying only essential infrastructure (roads, hospitals) and designated emergency shelters. "Points of interest" represent available shelter capacity, medical aid stations, or distribution points for essential supplies. The database contains rapidly updated information on shelter availability, resource levels, and road accessibility, potentially sourced from emergency services and citizen reports. User authentication is minimized, and the "interest list" becomes an emergency request for shelter or aid, anonymized as needed. The system defaults to a low-bandwidth, text-heavy display to function effectively over degraded communication networks.
• Mermaid Diagram:

  graph TD
      A[Disaster-Affected User] --> B{Low-Bandwidth Emergency Interface}
      B --> C[Simplified Disaster Map (Essential Info Only)]
      C -- Limited Interaction --> D[Highlighted Emergency Shelters / Aid Stations]
      D --> E[Emergency Database (Real-time Capacity, Resources)]
      E --> F[Emergency Request Queue (Anonymized)]
      F --> G[Emergency Response Teams]
  

Combination Prior Art Scenarios with Open-Source Standards

1. US5852810 + OpenStreetMap (OSM) Data:

   • Scenario: Combining the geographic-specific information search system of US5852810 with the collaboratively gathered and freely available geospatial data from OpenStreetMap. Instead of proprietary map tables, the system's "map tables 21" (as described in the patent) are populated and dynamically updated using OSM data. The "map compiler 23" and "table builder 25" would be adapted to ingest and render vector tiles derived from OSM, allowing for greater detail and community-driven updates to geographic features and landmarks. This makes the "graphical maps" more robust and accurate through a public standard.

2. US5852810 + GeoJSON Standard:

   • Scenario: Integrating US5852810 with the GeoJSON standard for encoding geographic data structures. The "database 22" (SQL database in the preferred embodiment) would store property location data (coordinates) and associated metadata in GeoJSON format. When the "query handler 19" retrieves "property listings," it formats them as GeoJSON objects. The "map compiler 23" would then render these GeoJSON features directly onto the "quadrant map" or other graphical representations. This standardizes the exchange and representation of geographic points of interest, simplifying integration with other mapping tools and services.

3. US5852810 + ActivityPub Protocol for Decentralized Social Networking:

   • Scenario: Augmenting US5852810 with the ActivityPub protocol, an open, decentralized social networking protocol. The "interest list" and "property manager notification" (steps 124, 140, 142 in Claim 1) could be implemented as ActivityPub "activities." When a user adds a property to their interest list or sends an inquiry, this action is published as an ActivityPub "Create" activity to the property manager's ActivityPub-enabled "home page" or inbox, potentially across different decentralized platforms. This decentralizes the communication and notification aspects, removing reliance on a single email manager or proprietary messaging system.