The biggest threat facing open-source sensation Linux today isn't Windows and the voracious company that makes it, but an increasingly dangerous legal battle with the SCO Group, the owner of various copyrights, patents, and intellectual property for UNIX, the OS on which Linux is based. According to SCO, IBM and numerous other Linux makers and users are violating the law by using Linux because the OS includes code stolen from UNIX, and SCO is now suing IBM for $1 billion. The response from the Linux community thus far has been childish at best--one group responded by repeatedly attempting to hack into the SCO Web site, for example--but now that a handful of analysts have taken the opportunity to validate SCO's claims, the once-laughable lawsuit isn't causing chuckles anymore.

SCO's claim is simple enough: Linux has improved so quickly because programmers stole SCO's copyrighted source code directly from UNIX. Until recently, SCO hadn't provided any public proof of the claim, and many people saw the company's $1 billion lawsuit against IBM--complete with a threat to end IBM's UNIX license, which could force the company to stop selling its AIX products--as the struggling company's last-ditch effort to raise money through litigation. But since then, two analysts have signed SCO's nondisclosure agreement (NDA) and compared pieces of source code that are, they say, identical in both UNIX System V and Linux.

"\[We're showing UNIX\] code, line by line copied into Linux," said Chris Sontag, SCO's senior vice president and general manager of SCOsource. Analysts who have seen the source code comparison report that programmer comments as well as programming code are reproduced identically from UNIX to Linux, damning evidence that some people working on Linux have stolen copyrighted code to advance the freely available open-source solution. Sontag says he doesn't believe that anyone at IBM is directly responsible for the theft but that IBM is guilty of breach of contract because its UNIX license specifically prevents the company from distributing software derived from the UNIX source code. IBM is now the largest corporate Linux backer, and the company is in the process of migrating most of its server products to Linux.

Since independent analysts verified SCO's claims, open-source leaders started changing their tune regarding SCO, although some still haven't yet come to grips with the enormity of this problem. Open-source advocate Eric Raymond, for example, questioned whether the source code was copied from UNIX to Linux or in the reverse direction, a question that an examination of legacy source-code stores should easily answer. But Raymond and most of the Linux community aren't addressing the real problem: How did the wunderkind Linux find itself in such a compromising, Microsoft-like position? And how will the community bounce back from these claims of illegitimacy when the very process under which Linux is created fosters and even promotes theft?