US 5,649,104 · Granted 1997-07-15

The 1997 Patent That Invented Virtual Whiteboarding for Remote Teams

Imagine you're on a video call with friends, and one person is running software on their computer — but everyone else can see it on their screen too, and you can all draw annotations over it simultaneously. That's what this patent describes: a system that lets multiple computers share one running program and lets everyone annotate what they see in real time.

Curated and verified by the IsItPatented Editorial team

The plain-English version

What it protects

The claim covers a method and system for displaying a single application's output on multiple remote computers while allowing each participant to draw or annotate over their local copy of that display, and then syncing those annotations back to all other participants' screens. What's protected here is the specific technique for replicating both the host program's window and the user-drawn overlays across a network so that all participants see a unified, annotated view.

Why it matters

This patent captures the core mechanics of what would become essential infrastructure for remote collaboration: shared screen viewing plus distributed annotation. Filed in 1993 and granted in 1997, it arrived as the internet was entering workplaces, and it protects the idea that remote participants shouldn't just watch passively — they should be able to mark up, point out, and collaborate on the same visual space in real time. That fundamental shift enabled modern tools like Zoom whiteboards and collaborative design platforms.

Real-world use

When you're on a video call and a colleague shares their screen, then everyone draws arrows and circles on a shared document — you're using the principle this patent locked down.

Original USPTO abstract

The invention concerns using multiple computers to hold a conference. Under the invention, an application program can run on a single computer, yet remote participants can issue commands to the program. Remote participants can watch the program operate, because the invention replicates the display window of the running program onto the displays of the remote computers. Any participant can make annotations on the participant's own computer display. The invention copies the annotations to the displays of the other participants.

Patent details

Publication number: US 5,649,104
Filing date: 1993-03-19
Grant date: 1997-07-15
Assignee: Ncr Corporation
Inventor(s): CARLETON; ALLISON A., FITZPATRICK; CATHERINE M., POMMIER; THERESA M., SCHWARTZ; KRISTA S.
CPC class: G06F3/038

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