• September 21, 2009

Microsoft has filed five lawsuits against companies that allegedly engage in "malvertising," or distributing ads that lure Web users to download viruses or other malware.

The lawsuits, all filed in King County state court in Washington, allege that the companies managed their ad campaigns with Microsoft AdManager. Microsoft alleges that the ads appear to be legitimate, but actually "use a variety of technoloy tricks to deliver malicious content to website visitors."

The companies named in the lawsuits are Soft Solutions, Direct Ad, qiweroqw.com, ITmeter and ote2008.info.

Microsoft, which has previously filed suit against alleged phishers and instant message spammers, is seeking an injunction against the five companies and damages. --Wendy Davis