After four years of disputes in lesser courts, the US Supreme Court agreed Monday to hear Microsoft's case against the Department of Justice, in which the Redmond giant is fighting to keep law enforcement from accessing its email servers in Ireland, Reuters reports.

Federal prosecutors are asking the high court to hear the case, after a federal appeals court ruled in Microsoft's favor that the software giant did not have to provide law enforcement access to email messages that derived from a Hotmail account hosted on its Dublin, Ireland, servers, on the grounds that they are protected by Irish privacy laws. The DOJ wants to review emails stored on the servers, as part of its investigation into a drug trafficking case; the original subpoena was filed by DoJ in 2013.

Although the DOJ characterizes the lower court ruling as a threat to public safety and national security, Reuters cited a blog post by Brad Smith, Microsoft’s president and chief legal officer that a ruling against it would jeopardize the privacy not only of international citizens, but US citizens as well. “If U.S. law enforcement can obtain the emails of foreigners stored outside the United States," wrote Smith, "what’s to stop the government of another country from getting your emails even though they are located in the United States?” 

The ultimate resolution of the case may also have repercussions for the cloud computing industry in general and for transAtlantic data transfer agreements like Privacy Shield. 

Microsoft's case marks the first time a domestic company is fighting a US search warrant seeking to access to data the organization holds in other countries, Reuters notes.

Read more about the case here.