In April last year, AOL, Microsoft and Yahoo! began collaborating in the fight against the ever-growing problem of spam. Earthlink joined shortly afterwards, and since then the four industry leaders have been working with organisations across the industry to create technical standards and guidelines that will stop the worldwide flood of unsolicited commercial e-mail.
Part of the programme has involved suing hundreds of spammers under the US Controlling the Assault of Non-Solicited Pornography and Marketing Act, also known as CANSPAM.
According to reports, Microsoft has now filed over 100 actions in its fight against spam.
The software giant announced last week that it has filed nine further lawsuits against spammers, and that one of these targeted National Online Sales, which is a web hosting company rather than a direct spammer.
"This is the first action against a web host catering to spammers," Aaron Kornblum, lawyer for Microsoft, told Reuters. "They're providing a safe place for spammers to drive customers to."
According to Komblum, National Online Sales had tried to avoid legal action by basing its operations in China.