The Linux kernels at the heart of SCO’s legal claim contain thousands of files “misappropriated" from Unix, SCO has claimed.
SCO believes the Linux 2.4 and 2.5 kernels, widely used in a variety of open-source systems, contain at least 1,549 files "misappropriated" from Unix.
The claim is intended to dismiss claims by some experts that the extent of disputed code in open-source products was relatively limited, allowing users to extract it to avoid paying the licence fee to SCO.
Chris Sontag, senior vice president and general manager of the firm's SCOsource division, said this code is in all the Linux distributions based around the 2.4 kernel, including those from Red Hat and SuSE.
Sontag added that the 1,549 figure could rise as SCO continues its efforts to discover further examples of infringing code and files in Linux. "That's just the number identified so far - it will probably end up being a lot higher," he said.
SCO Group president and chief executive officer Darl McBride claimed "the DNA of Linux comes from Unix", adding that if the offending code were to be taken out of Linux it would be equivalent to taking out the middle 30 floors from a 60-floor building.
Sontag claimed the alleged wholesale misappropriation of Unix code from its proprietary Unix operating system by IBM and others had been critical to the growth in Linux uptake.
As well as comparing code contained in the Linux 2.4 and 2.5 kernels with its own Unix code to try and identify examples of "literal" line-for-line copying, Sontag said SCO is using pattern recognition software to find examples of "obfuscated" code where the original Unix code had been altered slightly "with intent" by IBM and others to try and hide its origins.