SCO's Smoking-Gun Tour
Is SCO's smoking gun against IBM a sheet of 8 x 11 paper with pertinent lines of programming highlighted in red and blue?

This code, which was allegedly lifted almost verbatim from Unix to Linux, belongs to a large unnamed hardware vendor that isn't IBM, according to SCO, which was waving it around late in July.

But SCO argues it is evidence that many companies are violating its intellectual property, says Chris Sontag, general manager for SCO's SCOsource unit. SCO acquired not just the source code for Unix System 5 from AT&T years ago—but the contracts that pertain to its use by commercial software and hardware makers.

Sontag is making the rounds with press and analysts, arguing IBM is the "ringleader," something akin to an industrywide porting of Unix to Linux without permission.

His presentation boils down to this: IBM "donated" some of the functionality from its own Unix variant, known as AIX, to Linux version 2.4 and beyond. This helped the open-source software grow to handle nonuniform memory access (NUMA), journal file system and other important features for an operating system asked to be a workhorse of enterprise computers. "How did this happen in that short of time?" asks Sontag. "A third or more of the Linux 2.4 kernel is at issue."
According to Sontag, IBM, along with other vendors, gave Linux a helping hand and violated a "derivatives clause" in the contracts for using Unix System 5. The contracts appear to say the source code can be only used for internal purposes and can't be redistributed elsewhere.

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