Industry experts believe Sun Microsystems' pact with Microsoft could affect Microsoft's challenge to last month's European Union antitrust ruling.
Some thought the move might paint the software giant as a more fair-playing competitor, while others predicted that Microsoft's willingness to share server information with Sun would weaken its appeal argument that its intellectual property rights are being compromised by the EU ruling.
"If Microsoft has let by agreement Sun have what would it would have otherwise had to give competitors under the EU ruling, it could hurt its case," said Chris Bright, a London-based antitrust attorney with Shearman and Sterling.
But other industry watchers see the alliance as a potential feather in Microsoft's cap.
IDC analyst Chris Ingle said that although the exact details of the technical information Microsoft has agreed to give to Sun are unclear - making it difficult to say whether that information is the same as that dictated by the ruling - he believed the pact "relieves a source of pressure to Microsoft".
Microsoft no longer needs to worry about dedicating further money and resources to fighting litigation fired from Sun. Furthermore, Sun has agreed to remain silent against Microsoft's appeal.
However, Sun can still be called to give further evidence.
"Theoretically, the competition authorities can force [Sun] to disclose more information," said Robert Harrison, a European patent and trademark attorney with Rouse Patents in Germany.
"But they already gave them the smoking guns and jewels ... that's all in the background of the EU's case."
Although Lee Patch, vice president of legal affairs for Sun, said his company would now be "less visible" in the EU case, he added that it still supports the ruling.
Sun lawyer Michael Reynolds declined to comment on the company's further co-operation in the case. "[The Microsoft agreement] only just happened and we are still considering all that."
Legal details aside, RedMonk analyst James Governor believed the overarching effect of the agreement will be a softening of Microsoft's image.
"It's hard to see this as not in Microsoft's favour. When they sit down with the EU, they can say we work with Sun and we can work with anyone," he said.
However, both Microsoft and the EU see the Sun agreement as separate from the antitrust ruling, and forecast no subsequent change in the case.
"Our decision stands," said European Commission spokeswoman Amelia Torres. "Our decisions work in the interest of competition and consumers and are not related to any one competitor or any one contract."
The EU case and the Sun agreement need to be seen separately, according to Microsoft spokesman Tom Brookes.
"There's a massive difference between an order of compulsory license of Microsoft's intellectual property to a number of industry players and a reciprocal agreement between two industry players in which the exchange of intellectual property is a part. The effect and practicality is completely different even if some of the technical information could be the same," he said.
Microsoft UK spokesman Hugh Davies acknowledged that the company's competitive image could be improved by the agreement. "Clearly, the main protagonist in the case is no longer finding fault with us."
Scarlet Pruitt writes for IDG News Service