do read perens' comments linked to in that article also.
just one small example of SCO's circular logic:
they are reported in that article to say the following two things:
* the public domain code under question on the famous slides has been refined since being released under the BSD licence, and incorporated into SCO owned versions of unix. lets assume this is true for now, even though Perens shows fairly conclusively that it is a lie.
* linux contains the refined code, stripped of SCO copyright, which is illegal.
Now let me just think for a moment, if it's got a SCO copyright, then presumably SCO stripped its original BSD copyright in order to use it in the first place. This is clearly a violation of the BSD licence which was attached to the code in question initially. This licence, unlike the GPL has been tested in court and found to be sound.
I for one wish they would hurry up and have their court battle so SCO can get the slapdown they need. Also it would enable the GPL to be tested in court for the first time.