By Stephen Samuel

From the latest developments in the SCO/IBM battle, it now appears to be the case that SCO is claiming that it's UNIX licenses are virulently viral. It's claiming that the SYSV code that have been illegally transferred to Linux include Non-Uniform Memory Architecture (NUMA) and Read-Copy-Update (RCU) technology. The interesting thing is that that code was written by a company that was bought by IBM and doesn't currently exist in SCO's own versions of Unix, so how do they claim ownership?

Their claim, it would seem, comes from license terms in the old AT&T Unix licenses. According to these documents, the licensees deeded all derivative works back to AT&T. Although I haven't seen a copy of these precise license terms, I can think of a few ways in which such language might be read.

The most benign would be that AT&T was to get back the rights to patches to their own code. I.E. If IBM were to fix a problem with the cat command, AT&T (and now SCO) would have the right to distribute those bug fixes and updates to other licensees. This would not, however, include the rights to new code developed whole, cloth. Under this reading, SCO would clearly not have any rights to thing like RCU and NUMA.

A second reading is that the language does extend to included code but is, in fact, a non-exclusive license. In other words, AT&T might have been gained the right to include customer improvements of all sorts in it's own code, but the customers who developed such code would still have general ownership and control. This would actually be along the lines of what the GPL requires, except for the face that the code would only be available to the UNIX code owner and not the public generally -- although AT&T (and now SCO) would have the right to make that code available to the general public or just to specific parties. (A modified version of this reading would be that anything ever developed for a version of Unix is automagically cros-licensed to all UNIX licensees).

The nastiest reading (and the only reading in line with SCO's current legal maneuvering) would be that SCO has rights to, and control over, anything that is included in a licensee's 'derivative' version of Unix. SCO, for all intents and purposes, is claiming to own anything that has ever touched licensed code.

Although SCO is apparently now saying that licensees still own the copyright the only reading of SCO's claims to RCU is that they can prevent such code from being used anywhere other than in UNIX. In my world, this is effectively ownership of the code. Let me put it another way: SCO is claiming that they own AIX -- pretty much lock, stock and barrel. I would go so far as to say that, after barring IBM from distributing AIX, they might even be able to rebrand and resell AIX on their own, if they so choose.

Now some people might claim that this is the same problem as exists in the GPL, but that's not quite true. Although the GPL requires someone who distributes GPL'ed software to license any additions or modifications to the GPL'ed code, the author of the new code still owns it. They are free to relicense it, reuse it and do pretty much whatever they want with it as long as they don't limit the GPL rights of anybody who receives it under the GPL. SCO, on the other hand is suing IBM for relicensing their own code.

By the way, this isn't just IBM's problem. If SCO succeeds at this argument, they won't just own AIX. They could also own IRIX (SGI), HPUX(HP), Ultrix(HP, nee DEC) Solaris (SUN) and pretty much any other version of Unix created by a company that signed a similar license. In fact, they could soon end up owning Windows, as well (Depending on the terms of their recently inked license)..

SCO hasn't just picked a fight with IBM and the Linux community. Although it may not be clear yet, they've declared war against the entire UNIX universe. They've grabbed a tiger by the tail and I expect that they're hanging on for dear life.