US 6,564,261 · Granted 2003-05-13

The Patent That Let Strangers Chat Without Revealing Who They Are

Imagine a middleman service that lets two people message or call each other without either one knowing the other's real phone number, address, or device type. This 2003 patent describes exactly that—a network backbone that routes conversations between users while keeping their identities hidden, whether they're chatting on a PC, phone, or mobile device.

Curated and verified by the IsItPatented Editorial team

The plain-English version

What it protects

The claim covers a distributed system where users register with a unique network ID in a cluster of servers, and all messages between users are routed through intermediate routing services instead of going directly peer-to-peer. What's protected here is the method of brokering communication sessions (text chat, voice calls, video conferences, or SMS) between anonymous users across different device types and networks—including both IP networks and traditional phone networks—without the initiating user needing to know what device the other person is using or their actual contact information.

Why it matters

Filed in 2000 and granted in 2003, this patent captures core infrastructure that became foundational to modern messaging platforms and anonymous communication services. By protecting the concept of hiding user identity while routing messages through intermediate servers, it established intellectual property control over a key privacy-preserving architecture. This kind of anonymization layer became essential as chat and calling services grew beyond direct peer connections into platform-mediated ecosystems where users need privacy protection.

Real-world use

Every time you send a message through an app that masks your phone number, or make a call through a service that doesn't require both parties to exchange direct contact info, you're using technology that traces back to this routing and anonymization concept.

Original USPTO abstract

A network provides users with a simple and secure way of establishing communication sessions with other users or services, running either over IP networks or other networks, e.g., PSTN. In a sense, the network can broker communication services between two or more users (e.g., people) and/or services. A plurality of different clusters of servers is provided, and each of the clusters may be linked together. In certain embodiments, each cluster includes multiple servers. Users are registered within some specific cluster and given a unique system/network ID. In certain embodiments, messages are not sent directly between users, but instead through at least one intermediate routing service (RS) provided on a server of one of the users. Thus, in certain embodiments, a user may hide or mask his/her personal information from other users even when communicating with them. In certain embodiments, a user may establish a communication session with another user without knowledge of the client device (e.g., PC, mobile phone, etc.) being used by the other user; as the network arranges for communication (e.g., text chat session, voice chat session (PC to PC, PC to PSTN, or PC to mobile phone), web conference, or pages (PC to PC, PC to SMS)) between the users regardless of the client device being used by the called user. Thus, the network enables any of the above communication services between users, and the initiating user need not know whether the other user is currently online via his/her PC or may instead be reached via pager or mobile phone.

Patent details

Publication number: US 6,564,261
Filing date: 2000-05-09
Grant date: 2003-05-13
Assignee: Telefonaktiebolaget Lm Ericsson (Publ)
Inventor(s): GUDJONSSON GUDJON M., EMILSSON KJARTAN PIERRE
CPC class: H04L12/1818

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