Microsoft Corp. and Sun Microsystems Inc. finally have something in common: they both have signed Unix licensing agreements with The SCO Group in the last year.

The licensing agreements, which cover source code and patents contained in SCO's Unix operating system, will net SCO a total of US$13.25 million in 2003, according to documents filed by SCO with the Securities and Exchange Commission this week.

Sun's license is one of several it has signed with the various owners of the Unix System V source code, of whom SCO is the latest, since 1994, said John Loiacono, the vice president of Sun's Operating Platforms group. The most recent license, signed in February of this year, "licensed several hundred drivers to connect, essentially, peripheral devices to the operating system," he said.

Microsoft announced a similar licensing deal with SCO in May of this year -- a move that some industry observers interpreted as supporting SCO's ongoing breach of contract lawsuit with IBM Corp.

Sun's agreement can be seen in a similar light, according to Harry Fenik, the president of industry consulting firm The Sageza Group Inc. "I would wager that Sun saw this as an opportunity to bolster a comrade in arms," he said. "From Sun's perspective right now, the big enemy is IBM."

Sun's Loiacono disagreed. "The motivation we have is very different from what they have for licensing," he said. "I never want to be lumped into any categories with Microsoft other than profitability," he said.

The licensing deal with Sun is important because it provides SCO with the funds to prolong its lawsuit with IBM, and not because it indicates that Sun recognizes the validity of SCO's legal claims, Fenik said. "I don't think it's meaningful at all," he said. "They made a buy versus build decision (for Solaris x86 Platform Edition) to get access to a bunch of drivers for contemporary versions of Intel (Corp.) hardware," he said.

Because Sun purchased strong intellectual property (IP) rights with this and the various other Unix System V licenses it has signed with SCO over the last decade, it can now indemnify users of its Solaris x86 against lawsuits, Loiacono said. "I have a different license than what IBM purchased," he said. "I wanted complete ownership of my IP, so I bought IP rights outright."

IBM has repeatedly stated that it would "stand by" users of its AIX operating system, who appear to be threatened by the lawsuit, but it has stopped short of saying it would indemnify them.

Whether or not IBM had signed a license similar to Sun's would have had no bearing on SCO's lawsuit, according to SCO spokesman Blake Stowell.

"It doesn't really pertain to whether (IBM) purchased an additional license or not. What it really comes down to is whether they honored their contract or not," he said. "This isn't blackmail money," he added.