Doug Engelbart Patented the Mouse and Made Ten Thousand Dollars

US3541541 was filed on June 21, 1967, and issued on November 17, 1970, three years later. It is titled, with the relentless dryness that characterizes hardware patents, "X-Y Position Indicator for a Display System." The inventor named on it is Douglas C. Engelbart of the Stanford Research Institute. The first working device was built to his design by his SRI colleague William K. English, whose name is not on the patent.

The drawings in the patent show a small hand-held box with two perpendicular wheels underneath; the first one English built was carved from wood. As you push the block, the wheels rotate at rates proportional to your motion in the X and Y directions. Wires inside translate that rotation into a position on a screen. There is a single button on top.

It was, of course, the mouse.

The Mother of All Demos

The patent was filed about eighteen months before the device was first shown publicly. On December 9, 1968, in San Francisco, Engelbart gave what is now universally called the "Mother of All Demos." In ninety minutes, he demonstrated, working live in front of an audience of about a thousand people: a graphical user interface, hypertext links, real-time collaborative editing, video conferencing, dynamic outlining, and the mouse itself. None of these things existed in the consumer computing world. Most would not exist there for another fifteen to twenty-five years.

The audience response was, by most accounts, polite confusion. People understood what they had seen — there was no doubt the demo had worked — but the path from "this is what SRI built" to "this is what every office in America will use" was not yet visible. SRI licensed the mouse patent to a few interested parties. Apple Computer paid SRI roughly $40,000 for a non-exclusive license in the late 1970s, before the Macintosh.

Engelbart himself was reportedly paid about ten thousand dollars by SRI for the invention, in keeping with standard institutional employment arrangements.

What expired before it was needed

US3541541 was a seventeen-year patent, the standard term at the time. It expired in 1987. The Macintosh, the first mass-market computer to ship with a mouse, was released in 1984. By the time the world genuinely needed mice in volume — Windows 95, the graphical web, the explosion of personal computing — Engelbart's patent was three years into the public domain.

The mouse Engelbart designed and English built in the 1960s sold something like a billion units in the following decades. Engelbart received almost none of that money. He spent the rest of his career on the rest of the demo — collaborative editing, hypertext, the augmentation of human intellect — and watched the world adopt his most trivial invention while ignoring the larger system he had built it to serve.

He died in 2013. He had received the Turing Award in 1997 and the National Medal of Technology in 2000. The mouse on the desk in front of you is, in mechanical lineage, a direct descendant of US3541541.

See the original

The full text and figures of US3541541 are on Google Patents.