But SCO also said it will open a new copyright infringement claim in its legal attack.
In a hearing in Salt Lake City, federal judge Dale A. Kimball required SCO to produce two key batches of information IBM had sought in the case.
In one batch, called Interrogatory No. 12, IBM sought "all source code and other material in Linux...to which plaintiff (SCO) has rights; and the nature of plaintiff's rights." In the second, Interrogatory No. 13, Big Blue sought a detailed description of how SCO believes IBM has infringed SCO's rights and whether SCO ever distributed the source code described in Interrogatory No. 12.
The information IBM sought is at the heart of the case, a bold lawsuit SCO began in March that alleges IBM moved technology from Unix to Linux against the terms of its contract with SCO, violating trade secrets in the process. SCO is seeking $3bn (£1.74bn) from Big Blue, and is also trying to compel Linux-using corporations to license SCO's Unix. The judge's decision is one of the first moves in a case that will affect not just IBM but also other computing giants including Oracle, Hewlett-Packard, SAP and Dell that have embraced Linux.
IBM in August countersued with four patent violation claims and a defense that charges SCO with violating the terms of the General Public License (GPL) that governs Linux.
In the spring, when SCO first said Unix code had been copied into Linux, chief executive Darl McBride told CNET News.com, "We will be happy to show the evidence we have at the appropriate time in a court setting," but thus far the company hasn't done so.
IBM welcomed Kimball's decision. "IBM has said all along SCO has failed to show evidence to back its claims. We are very pleased the court has indicated it will compel SCO to finally back up its claims instead of relying on marketplace FUD" (fear, uncertainty and doubt), spokeswoman Trink Guarino said.
With interrogatory No. 12, IBM is essentially seeking to pin down what precisely SCO believes is in Linux that infringes Unix intellectual property. Though it hasn't said so in court, SCO executives in interviews have pointed to Unix technology including read-copy update (RCU), symmetrical multiprocessing (SMP), nonuniform memory access (NUMA) and IBM's Journaled File System (JFS).
Work on that software took place at IBM or a company called Sequent it acquired. SCO doesn't dispute that IBM owns copyrights to that software but does argue that the agreement under which IBM and Sequent licensed Unix prohibit Big Blue from making the software public.
Interrogatory No. 13, in which IBM is trying to find out if SCO distributed Linux software that violates SCO's Unix intellectual property rights, would provide evidence that relates to IBM's counterattack. IBM argues that SCO's distribution of a Linux product means it has agreed to the GPL's terms and therefore given permission to use that particular Unix technology in Linux.
Another charge coming
To the original charges in the case, SCO plans to add a new one: copyright infringement.
SCO's attorneys "decided to notify the court they will be adding (copyright claims) as part of the claims. There will be a new filing on that coming out in the near future," SCO spokesman Blake Stowell said. The attorneys told Kimball of the intention on Friday, Stowell said.
SCO wasn't legally permitted to include copyright claims until it resolved a tussle with Novell -- which sold much of its Unix intellectual property rights to SCO's predecessor -- over who actually held the copyrights. Only in June did SCO unearth the document that showed it had copyrights.
But thus far, its copyright actions have been unusual, said intellectual-property attorney John Ferrell of Carr & Ferrell.
"Since May, SCO has been saying they have proof of copyright violations by IBM and the rest of the Linux community, yet they've provided nothing that's been very convincing," Ferrell said. Without that evidence, SCO's attempt to force Linux-using corporations to license SCO's Unix is weakened, he said. "It seems if you're trying to get people to pay, it's reasonable to show them what the violation is."
SCO and IBM have each filed several motions to try to compel the other side to release information. In a motion Wednesday, IBM criticised SCO for delivering source code to IBM that had been printed on 1 million sheets of paper.
"Knowing full well that IBM would need its source code in electronic form so that proper analyses -- such as those SCO itself claims to have performed -- could be conducted, SCO instead produced the source code on onem sheets of paper," IBM said in the motion. "The only reason for SCO's production of code on paper was, we believe, to stall the progress of these proceedings while giving the (false) impression of being forthcoming in its discovery responses."
In response to IBM's complaint, Stowell said, "If a company wants code, it's the other party's decision to provide that any way they feel like providing that."
Kimball on Friday also scheduled a 23 January hearing to address SCO's concerns that IBM isn't being sufficiently forthcoming, Stowell said. SCO is seeking source code to versions of Unix that IBM has developed and sold.
The attorney representing SCO on Friday was Kevin McBride, whom Stowell said is the SCO chief executive's brother.
In other legal action, IBM on Wednesday subpoenaed Sun Microsystems; which recently expanded its Unix licence with SCO Group and has a warrant to purchase shares in the company; Schwartz Communications; a public relations firm that represents SCO; and defence contractor Northrop Grumman. IBM spokeswoman Guarino couldn't immediately describe the purpose of the subpoenas.
One Fortune 500 company signed up for SCO's program to buy Unix licences for running Linux, but Stowell said Northrop Grumman was not that company.
A Northrop Grumman representative declined to comment on the company's legal matters.
