IBM has also been ordered to provide the programmer's notes, design documents, comments and notes of the 3,000 people who made the most contributions and changes to both products.
The dispute began in March 2003 when SCO sued IBM, accusing the Linux distributor of letting parts of UNIX 'slip' into Linux in breach of SCO's rights. SCO originally sued IBM for $1 billion, increased the claim to $3 billion, and then gained approval for another increase to $5 billion.
IBM counterclaimed, arguing firstly that SCO is in breach of the General Public Licence, or GPL, which underpins the distribution of most open source software, and then accusing SCO of infringing IBM's own intellectual property rights.
In April 2004, IBM asked the District Court in Salt Lake City to declare that it has not infringed any SCO copyright through its Linux activities – an attempt to short circuit the most controversial case in the evolution of open source software.
IBM then filed a motion for summary judgment – i.e. judgment without trial – arguing that SCO has produced no evidence of copyright infringement and should therefore not be allowed to proceed with the claim. The court has yet to rule on this issue.
The past six months have seen a flurry of motions by both parties, mostly relating to the discovery process – the means by which one party ensures that it is given access to critical documents held by the other side.
SCO had asked for access to two IBM storage systems, known respectively as the Configuration Management and Version Control (CMVC) system and Revision Control System (RCS), in order that it might identify any parts of AIX and Dynix that infringed SCO's copyright.
On Tuesday, US Magistrate Judge Brooke Wells ruled partly in favour of SCO, ordering IBM to produce details of all versions and all changes to the AIX and Dynix codes, but without allowing access to the CMVC and RCS systems at this time.
"These systems allegedly contain source code that is outside the scope of the present litigation," said the Judge.
However, she added that the court would allow SCO unfettered access if IBM did not provide all the AIX and Dynix information.
She also ordered Big Blue to produce the design documents, notes and contact details of the 3,000 contributors most involved in developing the systems.