The General Public License, or GPL, is a novel thing. It was created by open source pioneer Richard Stallman, who also developed GNU, the open-source tools and apps that turn a Linux kernel into a Linux operating system. The GPL is intended to ensure that independent programmers and companies uphold the spirit of free software. "Free as in speech, not beer," is Stallman's oft-quoted motto regarding free software.The GPL essentially states this: GPL-protected software may be changed, modified and even packaged and resold by anyone, under the condition that any changes and modifications are redistributed back to the open source community. This keeps a company from taking Linux, writing proprietary applications and add-ons, then reselling it as an\u00a0operating system\u00a0without showing anyone what it did to the software.The GPL also spells out how GPL-protected software can be sold, but also copied freely by those who buy it. Software protected under the GPL includes Linux, MySQL, and a host of other programs.Now the GPL could be put to the ultimate test - scrutiny from a judge. This stems from the SCO Group's much-publicized lawsuit against IBM which claims that IBM unlawfully used SCO's copyrighted Unix code to beef up Linux. As part of its campaign, SCO has started selling a "license" which it says would protect anyone using Linux from being in violation of SCO's Unix licensing rules, in the event that a court sides with SCO - this, of course, flies in the face of the GPL. SCO also intends to prove that the GPL itself is invalid. SCO's argument is that the GPL - which allows software copying - it actually pre-empted by federal copyright law, which bars copying.To prove its case, the SCO Group has the high-powered law firm of Boies Schiller & Flexner, LLP on its side - Boise, being David Boies, of Microsoft trust-bust case fame. But you can be sure that IBM, with $1 billion invested in Linux, will put every pinstriped legal eagle on this case.What could this all mean? If the GPL is nullified, any person or company who ever contributed to the Linux code base could come out of the woodwork and start making licensing claims. Linux users could be violating the law, and the activity of open source development could be stymied.Strange to think that the fate of Linux and open source may hinge on Big Blue's corporate attorneys, battling the man whom many Linux fans may have rooted for when he tried to take apart Microsoft.Next: one lawyer's take on the SCO suit.