Questions about its plans to sue users are likely to dominate SCO's annual forum.
In two-weeks' time thousands of SCO users and Linux backers will converge on Las Vegas for the annual SCO Forum event.
However, this year, any product announcements and keynote speeches are likely to be overshadowed by SCO's recent claim that it owns the rights to a certain form of Linux software - a move that could have far-reaching consequences for the future development of open source software.
Two weeks ago, SCO dropped a bombshell when it announced that all users of software containing Linux kernel version 2.4 or above will need to buy SCO licences or face legal action for breach of copyright. There are no official statistics on how many organisations use the Linux 2.4 kernel, but some analysts estimate the number of installations to be in excess of one million worldwide.
SCO president and chief executive Darl McBride has claimed the 2.4 kernel contains code misappropriated from its proprietary System V Unix operating system.
In its endeavours to assert its intellectual property rights, SCO will focus initially on enterprise-level Linux users but McBride refused to rule out legal action against distributors such as Red Hat and even home users."We have broad rights against anyone that touches Linux," he said.
How serious is the threat?
At this stage, no one can say for sure how seriously Linux users should take SCO's threat. Experts can only speculate about the strength of SCO's case as it has so far refused to make public detailed evidence to support its copyright claim, for instance by opening up the disputed code it claims to own for independent verification.
SCO has also been vague about its proposed licensing model, except to say that it will be benchmarked with its Unixware licensing model and volume discounts will be available. The company is expected to clarify matters at the SCO Forum.
The good news for users is that SCO's announcement only appears to apply to the code in Linux kernel 2.4 that handles symmetric multiprocessing (SMP) scaling, which, strictly speaking, only applies to high-end datacentre installations. Therefore, those using Linux for common tasks such as web serving or file and print servers should be unaffected. Others could change their Linux usage to avoid liability and the need for a licence.
Many open source products are not affected by SCO's claims. Users of products containing earlier versions of the Linux kernel will also be unaffected.
Although McBride claimed that if all of the disputed code was taken out of Linux kernel 2.4 it would not work, it is possible that the open source community could write new code to fill the hole. But in the meantime, what can Linux users do to protect themselves from the threat of legal action?
How to protect yourself
Analysts are divided on the issue. Some, such as Gartner have advised firms not to install Linux software based on the 2.4 kernel until SCO's dispute has been resolved. Other analysts have told firms not to worry and install Linux regardless.
Legal experts have advised users to conduct due diligence to check what type of Linux they are using and whether they may be liable to SCO's copyright claim. If there is a risk of copyright infringement, users should request further clarification from SCO.
Although lawyers were reluctant to comment on SCO's chances of success before it reveals more detailed evidence, there are historical precedents for SCO's action that may give the company cause for concern.
In the mid-1990s, US telecoms giant AT&T launched a similar lawsuit to the SCO/IBM case against the BSD form of Unix. All that AT&T achieved was to force BSD to make a few changes to its code, and BSD is still shipping today.
Tony Lock, chief analyst at Bloor Research, said SCO's latest move was very aggressive but users should not be unduly worried. "SCO has an awful lot of opponents to get through before it gets to the end-users," he said. "It looks like SCO is trying to go for the jugular of everybody before the house falls down.
"It is a strange move on lots of levels. It is very hard to fathom what SCO's motives are in all this and you have to wonder what its long-term business plans are." Although enterprise implementations of Linux 2.4 kernel are fairly common, few are on big boxes that would be affected by the SMP problem, he added.
Analyst Rakesh Kumar of Meta Group described SCO's action as "panicked" and said it would be difficult for the company to prove copyright infringement. One issue is that users of Linux products based on the 2.4 kernel did not willfully infringe SCO's copyright claims, he explained.
But McBride claimed this would be irrelevant. He said IBM and others have transferred liability to end-users by not providing a warranty with their Linux products.
McBride said SCO's actions reflect a drive for compensation for its product being "damaged in the marketplace illegally". However, he has admitted that intellectual property revenue is becoming more important than product revenue for SCO, following declining sales of Unix on Intel.
The ultimate impact of SCO's threats remains to be seen but Graham Taylor, director of open source software promotion body OpenForum Europe, of which SCO is still a member, does not think the move will harm Linux adoption at all.
Others are more pessimistic and warned that SCO's legal claim could cause long-term damage to the culture of open-source development, where ideas and code are shared freely.
"SCO/Caldera's attempt to assert proprietary control of these technologies is an indirect but potent threat against the internet and the culture that maintains it," said Eric Raymond, president of the Open Source Initiative. "What is at stake here is not just the disposition of a particular volume of computer code, but what amounts to a power grab against the future."
Until SCO's arguments are tested in court, hundreds of thousands of Linux users have little choice but to consult their lawyers and sit tight.
In a nutshell
- SCO has warned users of Linux software containing the 2.4 Linux kernel, or above, that they must buy SCO licences or face legal action
- The company claims the 2.4 Linux kernel contains code misappropriated from its Unix System V operating system
- The move widens SCO's lawsuit against IBM, which it claims damaged demand for Unix by releasing SCO Unix System V code into the open source community
- Users have been advised to do due legal diligence to assess liability but, with exception of Gartner, analysts say to go ahead with Linux implementations.
SCO and Linux: a brief history
1969 Ken Thompson and Dennis Richie begin work on the original version of Unix at Bell Telephone Labs, then part of AT&T
1979 SCO launches its first Xenix version of Unix
1987-1990 IBM develops its own form of Unix, AIX
1991 Linus Torvalds creates Linux
1995 SCO acquires the Bell Labs Unix codebase. It sells two types of Unix: Openserver, based on its own Xenix code, and an early form of Unixware, based on the AT&T code
1998 SCO, IBM and Intel begin the ill-fated Project Monterey to port Unix for Intel's 64-bit Itanium chip
2001 SCO splits, with part of the company focusing on its Tarantella product, while the core SCO brand is taken over by Caldera
2002 Caldera starts trading as SCO
March 2003 SCO sues IBM for contract violation, claiming IBM released SCO's V Unix code into the open source community. IBM strenuously denies the claim
May 2003 SCO sends letters to 1,500 large enterprises warning them their Linux code may contain SCO's intellectual property
June 2003 SCO terminates IBM's Unix licence
July 2003 SCO claims users of software containing Linux kernel 2.4 will have to buy a licence.
Have your say
What do you think about SCO's actions? Are you concerned or angered by its targeting of Linux users? What will be the likely impact on the open source movement? Have you delayed a Linux implementation because of this? If you are a Linux user, do you intend to pay SCO's fees? Why do you think SCO is doing this? Let us know what you think.
This was first published in August 2003