Why challenge the GPL? (Score 5, Interesting)

I dont get this. SCO owns copyrights to Sys V Unix. Claims violation of confidentiality provisions in IBM contract, sues IBM for the same. So far, it has some amount of believability. Even their Caldera Linux distro is not necessarily fatal to their case, they are arguing ignorance anyway. So why this totally redundant campaign against the GPL? And how does a tiny company like SCO manage to get this much press attention? The guys who sued MS and won a court judgement certainly got nowhere near this much press. Sure the activism of Linux advocates explains some of it but still.. Could there be more to this than meets the eye?