In what could be a landmark case, the Redmond, Wash. company is arguing that such a warrant is not justified by law or the Constitution. Microsoft and other tech firms also fear that if the government prevails and can reach across borders, foreign individuals and businesses will flee to their non-U.S. competitors.
A privacy group, the Electronic Frontier Foundation, is planning to file an amicus brief this week that will argue in part that if Microsoft was to copy the data in Dublin so it can be retrieved by employees in Redmond, that act of copying would amount to a seizure under the Fourth Amendment, which the judge, the group says, does not have jurisdiction to order.
You can see a PDF of the argument here, thank to the Washington Post:
http://www.washingtonpost.com/r/2010-20 ... 0Brief.pdf