The long-running legal battle between IBM and SCO over the claim that Linux violates SCO's intellectual property took another twist on Tuesday, when IBM sent subpoenas to Microsoft, HP, Sun and Baystar.
IBM filed the subpoenas in the US District Court for Utah, where the case between IBM and SCO is being heard.
The subpoenas demand that these companies hand over a range of information, including details of their dealings with SCO, by 7 March. They will also have to give depositions later that month.
Groklaw, a legal Web site that had been following the case closely, believes the subpoenas could help to bring important information about the case to light.
"I begin to think that every question we've had, we will finally get to know the answer," wrote Groklaw's Pamela Jones, who published the subpoenas on her site.
Back in March 2003, SCO filed a lawsuit alleging that IBM had included code from Unix in Linux, which SCO claimed was a violation of its intellectual property. However, Novell then claimed that it, rather than SCO, owned the copyright on Unix, which prompted another lawsuit from SCO. In August 2003, IBM countersued SCO.
The subpoenas filed on Tuesday are part of the discovery phase of the case, where IBM can gather evidence in its defence.
Microsoft's subpoena runs to thirteen separate demands. They include handing over details of agreements relating to any Unix product involving Microsoft and SCO, and all communications between the two companies. In early 2003, Microsoft started paying SCO what eventually grew to $16.6m for a Unix licence, according to regulatory filings. Only long-time Unix fan Sun previously paid close to that, with a $9.3m licence deal. Microsoft provided a second, though indirect, boost in August or September of 2003, when it referred SCO to BayStar Capital, a fund that arranged a $50m investment.
Sun itself must reveal details of any agreements or licences between it and SCO for the UNIX source code, any documents referring to the open sourcing of any Sun Unix product, and Sun's involvement in the development of Linux.
HP has been ordered to give the court details of "agreements relating to any Unix software product involving HP and AT&T, USL, Novell, Santa Cruz and SCO", as well as details of any royalties HP pays for Unix and the origin of any Unix source code publicly disclosed or open sourced by HP.
It also forces HP to disclose any communications it has had with SCO since 28 June, 2002.
BayStar must hand over details of its communications, agreements and investments in SCO. It must also reveal communications between it and Microsoft regarding SCO, IBM and the ongoing court case.
BayStar invested $50m in SCO in October 2003, after it claimed that Linux violated its intellectual property. But by April 2004 BayStar began attempting to force changes at the firm.