The four internet service providers have coordinated their efforts to file six lawsuits against hundreds of defendants who are alleged to have sent out millions of unsolicited emails to web users.
ISPs have previously used various state laws in the US to try to clamp down on spammers but the suits have been filed after the introduction of a new law called the Can Spam Act, which came into effect on January 1.
It has criminalised specific tactics that spammers use to spread junk email, such as using false email addresses, re-routing emails to disguise their point of origin, and misleading subject lines such as "This is your lucky day", "Elite, Professional Invitation", and "Warning!!! These three minutes could change your life".
Les Seagraves, vice-president and chief privacy officer at EarthLink, said: "Together we are using a tough new federal law, combined with existing state laws, to let criminal spammers know that the nation's leading internet providers are united by a common goal -- stopping the flow of illegal and intrusive junk email and strengthening the internet experience for all users."
Some of the cases filed include AOL versus Davis Wolfgang Hawke, who is accused of sending millions of spam email messages directing AOL members to sites selling penis enlargement pills and weight loss supplements; another is Earthlink versus John Does 1-25, accused of sending millions of spam emails promoting sites that sell prescription drugs; and Yahoo! versus Eric Head, Matthew Head and Barry Head, who are accused of sending 94m emails to Yahoo! Mail.
"We're holding spammers directly accountable for the relentless infiltration of people's inboxes. We're acting on behalf of the millions of people who are saying 'enough is enough'," Yahoo! senior vice-president and general consul Mike Callahan said.
The alliance has vowed to tackle the problem by defeating one spam kingpin at a time, if that is what it takes. Internet companies are worried that spam, which is now thought to account for 65% of all the email sent, could end up turning users away from the medium.
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