Battle of the Xs

Owner of Unix operating system sues IBM, attacks Linux

4 min read

In a move that could have huge implications for the open software movement and the increasingly bitter IBM-Microsoft competition, The SCO Group Inc. (Lindon, Utah) has upped the ante in its lawsuit against IBM Corp. (Armonk, N.Y.). IBM stands accused, in a suit SCO originally filed in March, of adding Unix System V source code, which SCO believes it owns, to Linux, an open-source operating system that can be obtained free of charge.

In an amended brief, filed with the U.S. District Court for the District of Utah, on 16 June, SCO raised the amount of requested damages to US $3 billion from $1 billion. It also asked for a permanent injunction requiring IBM to destroy all copies of Unix, including AIX, IBM’s flavor of Unix installed on many of the company’s products.

IBM has denied all charges. In a curt press release issued 16 June, it accused SCO of attempting to create fear, uncertainty, and doubt among IBM’s customers and the open-source community. ”IBM’s Unix license is irrevocable, perpetual and fully paid up,” the release said.

At the heart of the dispute are IBM’s increasingly active support for Linux and Linux’s growing toehold in the segment of the server and workstation industry that runs on IA32 (Pentium) and IA64 (Itanium) microprocessors from Intel Corp. (Santa Clara, Calif.). Since SCO earns its bread and butter selling Unix to manufacturers of Intel-based servers and workstations, it feels threatened by Linux’s growing popularity. And it largely blames IBM for taking Linux from a PC operating system to one that can run on the enterprise-grade computers that store corporate records and databases and route intranet traffic.

”IBM has engaged in a course of conduct that is intentionally and foreseeably calculated to undermine and/or destroy the economic value of Unix anywhere and everywhere in the world,” said SCO in the suit filed on 6 March.

Unix’s convoluted past

The SCO Group is the fourth company to own rights to Unix System V code since AT&T started to develop it in the late 1960s [see timeline]. Novell Inc. (Provo, Utah) bought Unix from AT&T in 1993 and sold it two years later to the California company The Santa Cruz Operation Inc. (SCO No. 1). In 2001, Caldera Systems Inc. (Lindon, Utah) bought SCO’s Server Software and Professional Services divisions, and in 2002 changed its name to The SCO Group (SCO No. 2).

IBM licensed Unix System V from AT&T in 1985 and has continued to use it under the original agreement. In 1996, IBM, SCO, and Novell added Amendment X to the AT&T license, which, among other things, modified the payment of royalties to SCO and defined the rules under which IBM could provide copies of Unix source code to its contractors and customers.

During the time that Unix was owned by Santa Cruz Operation, the two companies launched Project Monterey to develop a version of Unix for Intel-based servers and workstations. The SCO Group claims that it had already been developing Unix for Intel platforms for 15 years and had been working with Intel on an operating system for the company’s new 64-bit processor (Itanium). According to SCO, IBM abruptly ended its participation in the project in 2001, after most of the technical work had been completed, declaring the project dead.

It is, in part, the confidential and proprietary information gained from Project Monterey that SCO accuses IBM of making available to Linux.

And yet Caldera (SCO No. 2) was until recently a Linux company. It was a participant in the Trillian Project, an effort by several companies, including IBM, to develop a version of Linux to run on Itanium. Even after Caldera acquired SCO in 2001, the company continued to trumpet its commitment to Linux and to boast of its plans to merge leading-edge Linux technology into its UnixWare source code.

Further clouding the litigation is SCO’s contention that IBM’s misappropriation of Unix System V code is not the only issue. It also claims that derivative works (extensions to the Unix kernel or code that runs inside it), even if written by IBM, are covered by the licensing agreement, as are the development methods. An example of derivative works that SCO says IBM added to Linux are the non-uniform memory access (NUMA) scheduler, which configures a cluster of microprocessors in a multiprocessing system to share memory.

SCO did not reveal exactly which Unix System V code it believes has been copied into Linux. But, it says, ”As a result of IBM’s wholesale disregard of its contractual and legal obligations to SCO, Linux 2.4.x and the development Linux kernel, 2.5.x, are filled with Unix source code, derivative works and methods. As such, Linux 2.4.x and Linux 2.5.x are unauthorized derivatives of Unix System V.”

That the SCO lawsuit is a thinly veiled attack against Linux is clearly shown in its amended brief, which accuses Linus Torvalds, the originator of Linux, of being unable or unwilling to identify the intellectual property origins of contributed Linux source code that has come in from many different sources.

The suit also raises the red flag of Linux’s threat to U.S. national security. The export of Unix technology, it says, could give nations, particularly rogue nations, the ability to build powerful multiprocessor supercomputers that can do encryption or design weapons. An industrial-strength version of Linux, with capabilities comparable to Unix, and freely available over the Internet, is a powerful tool, SCO argues.

No end in sight

There are several possible outcomes to this dispute. The simplest and possibly the fastest are that IBM and SCO could settle out of court or IBM could simply buy SCO. But these two possibilities are not likely, according to Bill Claybrook, an analyst with Aberdeen Group Inc. (Boston). Ruling them out leaves a full-fledged, drawn-out court battle. ”If SCO wins and IBM stumbles, then Microsoft is going to hold a big advantage in the market. If IBM wins, then Linux will take off among enterprises, and we will witness a big battle between Linux and Windows over the course of several years.”

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