IBM is trying to shoot down SCO's $5 billion suit against it and get a summary judgment by claiming that it can't possibly infringe on SCO's IP because SCO's Unix copyrights are "invalid and unenforceable," a broad latecomer counterclaim SCO is fighting, describing it as a search for "sweeping immunity."

IBM is trying to hang its defense on the contention that it doesn't "infringe, induce the infringement of, or contribute to the infringement of any SCO copyright through its Linux activities, including its use, reproduction and improvement of Linux, and that some or all of SCO's purported copyrights in Unix are invalid and unenforceable."

SCO claims IBM is afraid of SCO's breach of contract case and is trying to shift the point of contention between them to copyright infringement, a charge SCO made only because IBM continued to distribute AIX and Dynix after SCO terminated IBM's Unix licenses.

It has NOTHING to do with IBM's Linux activities, SCO says, and is merely a cute, albeit transparent, lawyer's trick to get both IBM and Linux off on a free pass.

Anyway, saying so doesn't make it so and IBM hasn't proven that Linux doesn't contain infringing code, which it would have to do for a summary judgment, SCO says.

SCO claims IBM twists the facts to arrive at its premise, misrepresenting SCO's discovery responses and even misquoting SCO's basic charges.

According to the story SCO tells the court in its latest 83-page filing, IBM is trying to pass off the discovery responses SCO gave IBM earlier this year as "complete, detailed and thorough," when in fact they were actually certified as partial answers, as the magistrate well knows since she herself ordered IBM to cough up the substantive discovery that SCO needed to complete its answers.

SCO reminds the court that asking for summary judgment before discovery has really been conducted flies in the face of federal procedures.

IBM, for its part, tells the court that SCO should be limited to the evidence SCO had on April 19 - mere days before IBM turned over a slice of the material it was ordered to give SCO - to oppose IBM's so-called tenth counterclaim or, if SCO seeks more discovery, then SCO should be tarred as "falsely certifying" its answers to IBM's interrogatories and IBM should be handed a summary judgment.

SCO quotes its discovery responses as distinctly reserving the right "to further supplement or amend its answers as discovery or further investigation may reveal."

SCO says it's not the first time IBM has misrepresented discovery to block SCO's ability to develop proof for trial. In fact, SCO says IBM has made a habit of it, adding insult to injury by then turning around and accusing SCO of delaying tactics when it's IBM who's doing the "stonewalling."

Besides a second motion to compel that SCO made on July 6, SCO's filing rebutting IBM's bid for a summary judgment basically asks the magistrate to again order IBM to produce the material that she already told IBM to produce back on March 3. SCO described the information as "rudimentary" stuff it asked for over a year ago.

Among other things, SCO is still waiting for IBM to produce all the versions of AIX and Dynix developed since 1999 - it wants to compare early and late code to see if IBM copied from Unix early on and then modified it. SCO also wants IBM to identify who contributed what so SCO knows who to depose. (It hasn't deposed any Linux contributors, including Linus Torvalds and the kernel maintainers, any of the people at IBM and Sequent who had access to Unix or produced AIX and Dynix or other companies that contributed to Linux.)

To date, IBM has only given SCO selected snapshots of late versions of AIX, ptx, Dynix and Dynix/ptx. SCO wants all versions of the control system and bug tracking information from 1984 to the present and all source code and log information for interim and released copies of the operating systems as well as design documents, white papers and programming notes.

It also wants IBM to detail all its myriad Linux projects and what it spent at least a billion dollars on.

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