Scott Richter, self-confessed Spam King and one-time peddler of ladies' underwear, has filed for bankruptcy, with Microsoft cited as the main reason.
According to reports, Richter has filed for Chapter 11 bankruptcy protection for his email marketing company, OptInRealBig.com.
Despite facing a $500,000 fine from New York attorney general Eliot Spitzer, Richter claims a pending multi-million dollar lawsuit from Microsoft is responsible for the bankruptcy.
The suit alleges that Richter, the world's third most prolific spammer according to anti-spam watchdog SpamHaus, is responsible for sending billions of spam messages with spoofed sender names and misleading subject lines.
While the lawsuit, which could see Richter forced to pay up to $40m damages if he loses, has yet to be settled, Microsoft is listed as the company's largest unsecured creditor, the Seattle Post Intelligencer reports.
Aaron Kornblum, Internet safety enforcement attorney for Microsoft, said "Any business model that is built on the sending of deceptive and unsolicited email is not one that will be profitable in the long term. It is not only annoying, it is illegal. Microsoft will continue to take legal action against spammers."