Path: utzoo!news-server.csri.toronto.edu!rutgers!news.cs.indiana.edu!ariel.unm.edu!cs.umn.edu!kksys!wd0gol!newave!john
From: john@newave.UUCP (John A. Weeks III)
Newsgroups: comp.misc
Subject: Re: AT&T owns X-windows ??  (was Re: Software Pat
Message-ID: <693@newave.UUCP>
Date: 10 Mar 91 16:56:52 GMT
References: <1991Mar1.184945.6946@mtxinu.COM> <996@caslon.cs.arizona.edu> <685@newave.UUCP> <6497@auspex.auspex.com>
Reply-To: john@newave.mn.org (John A. Weeks III)
Organization: NeWave Communications Ltd, Eden Prairie, MN
Lines: 20

In article <6497@auspex.auspex.com> guy@auspex.auspex.com (Guy Harris) writes:
> > I have heard that someone, and it might have been ATT, obtained a pattent
> > on using XOR to put a cursor on a terminal screen.

> No, it wasn't AT&T.  Did you have any reason to believe that it was?

I did, but I was slightly mistaken.  It is patent #4,197,590, owned
by Cadtrak.  It was upheld twice in court even though the technique
was used by others for many years before Cadtrak applied for the patent.
As a result, Cadtrak receives several million dollars a year in user fees
from a number of manufacturers.  Even though a 13 year might "invent" this
technique, you better not use it unless you are willing to pay for it.

-john-

-- 
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John A. Weeks III               (612) 942-6969               john@newave.mn.org
NeWave Communications                 ...uunet!rosevax!tcnet!wd0gol!newave!john
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