On Friday, Judge Dale Kimball of the U.S. District Court for the District of Utah issued a Summary Judgement in SCO Group vs. Novell (2:04-cv-00139-DAK) that effectively demolished SCO's claims to the copyright for Unix and will most likely end SCO's long running suit against IBM (2:03-cv-00294-DAK). The case, which was once seen as a threat to the open source software movement, started when SCO accused IBM of incorporating parts of SCO's copyrighted Unix code into open-source Linux. The case took an unexpected turn when Novell pointed out that SCO didn't own the copyrights to begin with. Novell claimed that when it sold its Unix business to Caldera (the predecessor to SCO) it merely licensed the code and did not actually transfer the copyrights. Indeed, the Asset Purchase Agreement incorporates a list of Excluded Assets which clearly states that "All copyrights and trademarks, except for the trademarks UNIX and UnixWare" and "All Patents" are not among the assets being sold. SCO argued from a number of angles that the agreement didn't mean what it said, or had been modified by other subsequent events, but the judge shot all of them down and declared that Novell still held the copyrights, and had the sole discretion as to whether to proceed against IBM for using Unix code in Linux. While SCO never really established that any of the Linux code came from Unix, the issue will be rendered moot if Novell, as expected, remains on good terms with IBM.
Unix and the Origins of Open Source Software
For most of the brief history of the computer business, the operating system (OS) has provided a set of useful abstractions and services, such as a file system, memory management, a process scheduler, device drivers, and network stacks, but this convenience came at the price of flexibility. Whether the OS came with the hardware or was sold separately, the source code was only available under very restricted circumstances. If your project required some new form of memory management or a different user interface, you were basically out of luck until the vendor got around to it. The one exception was Unix. Originally a skunkworks project at AT&T Bell Labs, it was designed to be portable among different hardware architectures and offered many innovative features. Since the 1956 consent decree that settled AT&T's antitrust case prohibited the company from entering the Information technology business, it couldn't aggressively sell Unix but it did license it widely to universities and research organizations. Since the license included source code, many of those licensees made improvements to the software.
I experienced this phenomenon years ago when I was at CCA building the Spatial Data Management System, which included a facility for moving a finite display window over an infinite data surface. It needed a way to have one process manage the scrolling of the display while a separate one loaded from disk the data just off-screen, similar to how Google Maps works, except that everything happened on one machine. Since the volume of data was far too large to move through Unix pipes, we needed a way to share memory between processes, a feature not present in Unix at the time. No problem. We retained Unix guru John S. Quarterman and he added the feature to the OS for us. Years later, Unix System V offered a similar feature but we didn't need to wait.
Our experience was hardly unique. There was a thriving culture around Unix, but with the peculiar licensing arrangements from AT&T, there was no organized, legal way for people to share the innovations. The situation improved somewhat when UC-Berkeley's Computer Systems Research Group started developing and distributing a version of Unix, but the Berkeley distributions were still entangled with the AT&T situation. It was into this breach that Linus Torvalds launched Linux. Linux was written from scratch, with no code derived from any previous versions of Unix, was available for free, and incorporated code provided my volunteers all over the world. It became, by most accounts, the most successful open-source software project in history. As it grew, it also became a target for occasional accusations that some the material provided by all of these volunteers may have been tainted by copyright or patent encumbrances. The most vocal and well-funded of these accusations came from SCO and had SCO prevailed would have been a serious setback for open source in general and Linux in particular. If Judge Kimball's ruling stands, and Novell sides with IBM, most of the fear, uncertainty, and doubt this case started will be dispelled and the open source software movement will continue to thrive.