Invalidity dossier
US 5280477
Network synchronous data distribution system
Current assignee: OL Security LLC
Added 9/23/2026, 5:44:20 PM
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Patent summary
Title, assignee, inventors, filing/issue dates, abstract, and a plain-language overview of the claims.
Patent Overview — US 5,280,477
Title: Network synchronous data distribution system
Patent number / application: US 5,280,477 A; Application US07/929,920
Inventor: Timothy J. Trapp
Original assignee: E Systems Inc (assignment recorded to E-SYSTEMS, INC., P.O. Box 660248)
Key dates: Priority/filing date 1992-08-17; granted/publication date 1994-01-18; anticipated expiration 2012-08-17. Current assignee listing: OL Security LLC.
Purpose and plain-language scope (per supplied text): The invention relates generally to systems for communicating data among remote devices, and specifically to a method and apparatus for communicating synchronous and asynchronous data between devices connected to a network or group of interconnected networks. The excerpt frames the problem in terms of addressing efficiency: individual addressing requires duplicating data packets to multiple recipients, while group addressing imposes a rigid structure, requires all devices to know the data types, is hard to change, and may not permit dynamically varying groups message-to-message. The stated aim is to let a transmitting device control which receiving devices tune into a given transmission without wasting transmission time on duplicate packets, including varying recipients on a message-by-message basis for synchronous signals. The disclosure is organized around figures showing a typical network (FIG. 1), a data link front end processor (FIG. 2), a system processor (FIG. 3), an integrated workstation (FIG. 4), network data paths (FIG. 5), and steps for initiating synchronous transfer (FIG. 6), setting up message filters (FIG. 7), transferring synchronous data (FIG. 8), and ending that transmission (FIG. 9).
What the excerpt does not establish: It does not reproduce any claims, so no claim scope can be quoted. It omits the detailed description and the remainder of FIG. 9's discussion. It does not establish the actual content of the message filters, the specific protocol, or how the method is implemented. It states no litigation, validity, or prior-art determinations. Classification listings (H04L12/64 family, H04L9/40) appear in the source but are not explained there.
Generated 10/1/2026, 9:43:19 PM
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Litigation summary
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PTAB challenges
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Assignment history
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Prior art
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Obviousness
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Extensions
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Derivative works
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