Yahoo sued over alleged pay-per-click fraud | CNET News.com
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A lawsuit filed this week alleges that Yahoo is charging advertisers for “premium” ads that are displayed on illegal sites that show spyware pop-up ads and typosquatter sites that appear when a surfer misspells a Web address.

Instead of the “highly targeted” sites the ads are supposed to appear on, the ads end up on low-quality sites that show random ads and little or no bona fide content, according to the lawsuit, filed Monday in New Jersey federal court.