When it comes to the legal controversy around Linux, it ain't over till it's over.

A Utah federal court judge last Friday made official what most everyone -- Linux vendors, open-source champions, intellectual property rights experts, brain-functioning investors -- already knew: SCO's five-year-old campaign to co-opt Linux is over. CIOs and other top business technology executives who are migrating portions of their infrastructures to Linux can breathe easier, as SCO won't come calling for its $1,399 per single CPU implementation of Linux, as it's been threatening. But this dog fight ain't completely over.

The judge ruled that SCO may have the rights to sell Unix, but the company doesn't own the IP to that operating system. Thus, SCO can't very well demand compensation from Linux customers and vendors should, as it has claimed for years, Linux contain parcels of Unix code.

The ruling, which effectively quashes a lawsuit SCO filed against Linux distributor Novell in 2004, stipulates that Novell owns Unix. SCO will probably press on in some way, but it should give up the hopeless legal fight. Meantime, whatever speculative investors it still had are now fleeing en masse.

The Utah judge has asked SCO and IBM -- the target of a separate SCO suit for alleged breach of its Unix contract -- to state where they think that case stands following the SCO v. Novell ruling. Only SCO chief Darl McBride would have the cajones to continue harassing IBM for violating rights that his company doesn't own, but that case is pretty much done regardless.

But hold off on the high fives. While SCO is all but out of the picture, Microsoft still looms large, claiming that Linux and other open source software violate some 235 of its patents. Over the past several months, Microsoft has aligned with Linux vendors Novell, Xandros, Linspire, and others, striking cross-licensing deals that protect their customers from any future Microsoft legal action around Linux.

Still murky is where market leader Red Hat's Linux customers stand amid Microsoft's posturing. Red Hat Linux shouldn't violate any SCO Unix rights for the same reasons Novell's Suse Linux doesn't. But don't count out Microsoft's ability to turn from Linux irritant to deep-pocketed litigant and keep the market off balance.