Kelihos botnet creator worked for antivirus company Microsoft says

The Kelihos botnet that was sending up to 3.8 billion spam e-mails per day before being taken offline was allegedly created and controlled by a software developer who formerly worked for an antivirus firm.

Source:
http://arstechnica.com/business/news/2012/01/kelihos-botnet-creator-worked-for-antivirus-company-microsoft-says.ars