The judge’s decision is the second time in recent weeks that Microsoft has failed to subpoena competitors to help it fight an EC ruling that may mean up to $2.4m in daily fines for the company.

Massachusetts district court judge Mark Wolf issued a 12-page court order stating that Microsoft had not proven that the EC case against the company would be unfair without the Novell documents.

Microsoft has claimed these documents would shed light on why an independent expert wrote reports criticizing Microsoft’s attempts to comply with a 2004 antitrust order from the EC. The European authorities had ordered Microsoft to make its code available to rivals so that would allow non-Microsoft work group servers to achieve full interoperability with Windows PCs and servers.

Wolf also said Microsoft’s attempt to obtain the papers from Waltham, Massachusetts-based Novell would undermine European law.

Enforcing Microsoft’s subpoena of Novell would circumvent and undermine the law of the European Community concerning how a litigant may obtain third-party documents, Wolf said in his ruling.

It is now evident that granting Microsoft the discovery it requests from Novell would interfere with the foreign tribunal, not assist it, he said.

Also, Microsoft erroneously repeatedly said the EC was unable to obtain the Novell papers and make them accessible to Microsoft, Wolf said.

In March, Microsoft’s attempts to subpoena documents relating to its case from Oracle Corp and Sun Microsystems Inc also were stymied by a Californian court. A New York court is currently considering a similar subpoena against IBM.

Computer science expert Professor Neil Barrett acted as the EC’s monitoring trustee when he reviewed Microsoft’s work to comply with the EC ruling. But his report in late December of Microsoft’s attempts to provide adequate documentation to its rivals was scathing.

Any programmer or programming team seeking to use the technical documentation for a real development exercise would be wholly and completely unable to proceed on the basis of the documentation, Barrett said in his report in late December.

But Microsoft has claimed the EC had inappropriate contacts with Barrett and its rival software makers and questioned the independence of Barrett’s report.

The EC has declined to address Microsoft’s allegations, but noted that Barrett was among a candidate list of experts provided by Microsoft.

The European Court of First Instance will soon hear Microsoft’s appeal against the EC’s 2004 antitrust ruling, in which it ordered Microsoft to pay $613m in fines.