Microsoft is stepping up its action against the operators of the Rustock botnet that terrorized computers around the world for years before it was taken down in March. The software giant is offering up to $250,000 for information leading to the capture and conviction of individuals responsible for the botnet. With that type of cash as an incentive, the Rustock operators may not be able to hide for long.

The Rustock botnet was responsible for a great quantity of the world's spam during the time it was active. The operators of the botnet are wanted for various criminal activities including counterfeit advertisements and violating the trademarks of Microsoft and pharmaceutical companies like Pfizer. With Rustock out of the picture, the world's spam levels are at their lowest levels since 2008. Do you know anybody associated with Rustock and looking for a reward?

Microsoft has filed a civil suit against the operators of Rustock with the defendants named as "John Doe" until their true identities can be ascertained. The notice of a reward is an attempt by Microsoft to determine the names of the defendants and is posted exactly four months (March 18 to July 18) after the initial complaint was made in U.S. District Court in Western Washington based in Seattle.

Microsoft believes the operators of Rustock to be of Russian decent or based in Russia and has taken out notices in Russian newspapers to notify the Rustock operators of the civil suit. Anyone with information on Rustock can contact Microsoft at avreward@microsoft.com.

"Microsoft has already been gathering strong evidence in our ongoing investigation and this reward aims to take that effort a step further," wrote Richard Boscovich, the senior attorney with Microsoft's digital crimes unit, on Microsoft's official blog. "We will continue to follow this case wherever it leads us and remain committed to working with our partners around the world to help people regain control of their Rustock-infected computers."