A federal judge has brought Microsoft one step closer to seizing control of 276 domains controlled by the Waledac botnet.

A magistrate judge in the U.S. District Court of Eastern Virginia decided Sept. 3 to recommend that a default judgment be granted in Microsoft's favor. The defendants in the case were given 14 days to object; if they do not, the judgment will be final.

“In this case, Microsoft presented evidence to the court that although the defendants did not come forward, they were aware of the case and actively tried to retaliate, attempting to launch a distributed denial of service (DDOS) attack against the law firm that filed the suit and even going so far as to threaten one of the researchers involved in the case,” according to Microsoft.

The legal action was the result of a joint investigation known as ‘Operation b49’ that also involved Symantec, Shadowserver Foundation, the University of Washington and others. Once capable of sending out more than 1.5 billion spam messages a day, the number of unique infected IP addresses has continued to decline, going from 64,000 during the week of July 23 to 58,000 as of Aug. 30.