IP Innovation, LLC, and Technology Licensing Corporation sued Red Hat und Novell at the Texas Eastern District Court because of patent violations. Both companys are specialised in purchasing and enforcing patents.
In most patent laws, prior art or state of the art is all information that has been disclosed to the public in any form before a given date. (cited)
This page is dedicated to collect any prior art to void the U.S. Patent 5,072,412.
An introduction on HowTo search for Prior Art can be found at the Open Source as Prior Art project.
Enter - Let's show the world that this wasn't a new invention in 1987 !